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a827f9f66e337105fac17adb352c48402bd668585a29a81be88c4491dc7fe556 | from functools import partial
from django.db.models.utils import make_model_tuple
from django.dispatch import Signal
class_prepared = Signal()
class ModelSignal(Signal):
"""
Signal subclass that allows the sender to be lazily specified as a string
of the `app_label.ModelName` form.
"""
def _lazy_method(self, method, apps, receiver, sender, **kwargs):
from django.db.models.options import Options
# This partial takes a single optional argument named "sender".
partial_method = partial(method, receiver, **kwargs)
if isinstance(sender, str):
apps = apps or Options.default_apps
apps.lazy_model_operation(partial_method, make_model_tuple(sender))
else:
return partial_method(sender)
def connect(self, receiver, sender=None, weak=True, dispatch_uid=None, apps=None):
self._lazy_method(
super().connect, apps, receiver, sender,
weak=weak, dispatch_uid=dispatch_uid,
)
def disconnect(self, receiver=None, sender=None, dispatch_uid=None, apps=None):
return self._lazy_method(
super().disconnect, apps, receiver, sender, dispatch_uid=dispatch_uid
)
pre_init = ModelSignal(use_caching=True)
post_init = ModelSignal(use_caching=True)
pre_save = ModelSignal(use_caching=True)
post_save = ModelSignal(use_caching=True)
pre_delete = ModelSignal(use_caching=True)
post_delete = ModelSignal(use_caching=True)
m2m_changed = ModelSignal(use_caching=True)
pre_migrate = Signal()
post_migrate = Signal()
|
e84b1d6336b35fcdb7787f889f3605b677956f091ff8dc11895d63c101de3531 | """
Various data structures used in query construction.
Factored out from django.db.models.query to avoid making the main module very
large and/or so that they can be used by other modules without getting into
circular import difficulties.
"""
import copy
import functools
import inspect
import warnings
from collections import namedtuple
from django.core.exceptions import FieldDoesNotExist, FieldError
from django.db.models.constants import LOOKUP_SEP
from django.utils import tree
from django.utils.deprecation import RemovedInDjango40Warning
# PathInfo is used when converting lookups (fk__somecol). The contents
# describe the relation in Model terms (model Options and Fields for both
# sides of the relation. The join_field is the field backing the relation.
PathInfo = namedtuple('PathInfo', 'from_opts to_opts target_fields join_field m2m direct filtered_relation')
class InvalidQueryType(type):
@property
def _subclasses(self):
return (FieldDoesNotExist, FieldError)
def __warn(self):
warnings.warn(
'The InvalidQuery exception class is deprecated. Use '
'FieldDoesNotExist or FieldError instead.',
category=RemovedInDjango40Warning,
stacklevel=4,
)
def __instancecheck__(self, instance):
self.__warn()
return isinstance(instance, self._subclasses) or super().__instancecheck__(instance)
def __subclasscheck__(self, subclass):
self.__warn()
return issubclass(subclass, self._subclasses) or super().__subclasscheck__(subclass)
class InvalidQuery(Exception, metaclass=InvalidQueryType):
pass
def subclasses(cls):
yield cls
for subclass in cls.__subclasses__():
yield from subclasses(subclass)
class Q(tree.Node):
"""
Encapsulate filters as objects that can then be combined logically (using
`&` and `|`).
"""
# Connection types
AND = 'AND'
OR = 'OR'
default = AND
conditional = True
def __init__(self, *args, _connector=None, _negated=False, **kwargs):
super().__init__(children=[*args, *sorted(kwargs.items())], connector=_connector, negated=_negated)
def _combine(self, other, conn):
if not isinstance(other, Q):
raise TypeError(other)
# If the other Q() is empty, ignore it and just use `self`.
if not other:
return copy.deepcopy(self)
# Or if this Q is empty, ignore it and just use `other`.
elif not self:
return copy.deepcopy(other)
obj = type(self)()
obj.connector = conn
obj.add(self, conn)
obj.add(other, conn)
return obj
def __or__(self, other):
return self._combine(other, self.OR)
def __and__(self, other):
return self._combine(other, self.AND)
def __invert__(self):
obj = type(self)()
obj.add(self, self.AND)
obj.negate()
return obj
def resolve_expression(self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False):
# We must promote any new joins to left outer joins so that when Q is
# used as an expression, rows aren't filtered due to joins.
clause, joins = query._add_q(
self, reuse, allow_joins=allow_joins, split_subq=False,
check_filterable=False,
)
query.promote_joins(joins)
return clause
def deconstruct(self):
path = '%s.%s' % (self.__class__.__module__, self.__class__.__name__)
if path.startswith('django.db.models.query_utils'):
path = path.replace('django.db.models.query_utils', 'django.db.models')
args, kwargs = (), {}
if len(self.children) == 1 and not isinstance(self.children[0], Q):
child = self.children[0]
kwargs = {child[0]: child[1]}
else:
args = tuple(self.children)
if self.connector != self.default:
kwargs = {'_connector': self.connector}
if self.negated:
kwargs['_negated'] = True
return path, args, kwargs
class DeferredAttribute:
"""
A wrapper for a deferred-loading field. When the value is read from this
object the first time, the query is executed.
"""
def __init__(self, field):
self.field = field
def __get__(self, instance, cls=None):
"""
Retrieve and caches the value from the datastore on the first lookup.
Return the cached value.
"""
if instance is None:
return self
data = instance.__dict__
field_name = self.field.attname
if field_name not in data:
# Let's see if the field is part of the parent chain. If so we
# might be able to reuse the already loaded value. Refs #18343.
val = self._check_parent_chain(instance)
if val is None:
instance.refresh_from_db(fields=[field_name])
val = getattr(instance, field_name)
data[field_name] = val
return data[field_name]
def _check_parent_chain(self, instance):
"""
Check if the field value can be fetched from a parent field already
loaded in the instance. This can be done if the to-be fetched
field is a primary key field.
"""
opts = instance._meta
link_field = opts.get_ancestor_link(self.field.model)
if self.field.primary_key and self.field != link_field:
return getattr(instance, link_field.attname)
return None
class RegisterLookupMixin:
@classmethod
def _get_lookup(cls, lookup_name):
return cls.get_lookups().get(lookup_name, None)
@classmethod
@functools.lru_cache(maxsize=None)
def get_lookups(cls):
class_lookups = [parent.__dict__.get('class_lookups', {}) for parent in inspect.getmro(cls)]
return cls.merge_dicts(class_lookups)
def get_lookup(self, lookup_name):
from django.db.models.lookups import Lookup
found = self._get_lookup(lookup_name)
if found is None and hasattr(self, 'output_field'):
return self.output_field.get_lookup(lookup_name)
if found is not None and not issubclass(found, Lookup):
return None
return found
def get_transform(self, lookup_name):
from django.db.models.lookups import Transform
found = self._get_lookup(lookup_name)
if found is None and hasattr(self, 'output_field'):
return self.output_field.get_transform(lookup_name)
if found is not None and not issubclass(found, Transform):
return None
return found
@staticmethod
def merge_dicts(dicts):
"""
Merge dicts in reverse to preference the order of the original list. e.g.,
merge_dicts([a, b]) will preference the keys in 'a' over those in 'b'.
"""
merged = {}
for d in reversed(dicts):
merged.update(d)
return merged
@classmethod
def _clear_cached_lookups(cls):
for subclass in subclasses(cls):
subclass.get_lookups.cache_clear()
@classmethod
def register_lookup(cls, lookup, lookup_name=None):
if lookup_name is None:
lookup_name = lookup.lookup_name
if 'class_lookups' not in cls.__dict__:
cls.class_lookups = {}
cls.class_lookups[lookup_name] = lookup
cls._clear_cached_lookups()
return lookup
@classmethod
def _unregister_lookup(cls, lookup, lookup_name=None):
"""
Remove given lookup from cls lookups. For use in tests only as it's
not thread-safe.
"""
if lookup_name is None:
lookup_name = lookup.lookup_name
del cls.class_lookups[lookup_name]
def select_related_descend(field, restricted, requested, load_fields, reverse=False):
"""
Return True if this field should be used to descend deeper for
select_related() purposes. Used by both the query construction code
(sql.query.fill_related_selections()) and the model instance creation code
(query.get_klass_info()).
Arguments:
* field - the field to be checked
* restricted - a boolean field, indicating if the field list has been
manually restricted using a requested clause)
* requested - The select_related() dictionary.
* load_fields - the set of fields to be loaded on this model
* reverse - boolean, True if we are checking a reverse select related
"""
if not field.remote_field:
return False
if field.remote_field.parent_link and not reverse:
return False
if restricted:
if reverse and field.related_query_name() not in requested:
return False
if not reverse and field.name not in requested:
return False
if not restricted and field.null:
return False
if load_fields:
if field.attname not in load_fields:
if restricted and field.name in requested:
msg = (
'Field %s.%s cannot be both deferred and traversed using '
'select_related at the same time.'
) % (field.model._meta.object_name, field.name)
raise FieldError(msg)
return True
def refs_expression(lookup_parts, annotations):
"""
Check if the lookup_parts contains references to the given annotations set.
Because the LOOKUP_SEP is contained in the default annotation names, check
each prefix of the lookup_parts for a match.
"""
for n in range(1, len(lookup_parts) + 1):
level_n_lookup = LOOKUP_SEP.join(lookup_parts[0:n])
if level_n_lookup in annotations and annotations[level_n_lookup]:
return annotations[level_n_lookup], lookup_parts[n:]
return False, ()
def check_rel_lookup_compatibility(model, target_opts, field):
"""
Check that self.model is compatible with target_opts. Compatibility
is OK if:
1) model and opts match (where proxy inheritance is removed)
2) model is parent of opts' model or the other way around
"""
def check(opts):
return (
model._meta.concrete_model == opts.concrete_model or
opts.concrete_model in model._meta.get_parent_list() or
model in opts.get_parent_list()
)
# If the field is a primary key, then doing a query against the field's
# model is ok, too. Consider the case:
# class Restaurant(models.Model):
# place = OneToOneField(Place, primary_key=True):
# Restaurant.objects.filter(pk__in=Restaurant.objects.all()).
# If we didn't have the primary key check, then pk__in (== place__in) would
# give Place's opts as the target opts, but Restaurant isn't compatible
# with that. This logic applies only to primary keys, as when doing __in=qs,
# we are going to turn this into __in=qs.values('pk') later on.
return (
check(target_opts) or
(getattr(field, 'primary_key', False) and check(field.model._meta))
)
class FilteredRelation:
"""Specify custom filtering in the ON clause of SQL joins."""
def __init__(self, relation_name, *, condition=Q()):
if not relation_name:
raise ValueError('relation_name cannot be empty.')
self.relation_name = relation_name
self.alias = None
if not isinstance(condition, Q):
raise ValueError('condition argument must be a Q() instance.')
self.condition = condition
self.path = []
def __eq__(self, other):
if not isinstance(other, self.__class__):
return NotImplemented
return (
self.relation_name == other.relation_name and
self.alias == other.alias and
self.condition == other.condition
)
def clone(self):
clone = FilteredRelation(self.relation_name, condition=self.condition)
clone.alias = self.alias
clone.path = self.path[:]
return clone
def resolve_expression(self, *args, **kwargs):
"""
QuerySet.annotate() only accepts expression-like arguments
(with a resolve_expression() method).
"""
raise NotImplementedError('FilteredRelation.resolve_expression() is unused.')
def as_sql(self, compiler, connection):
# Resolve the condition in Join.filtered_relation.
query = compiler.query
where = query.build_filtered_relation_q(self.condition, reuse=set(self.path))
return compiler.compile(where)
|
a61af9fff236c72d9d5ca289e22d5d0313c2cf2856eaac2e2670ce4c3b7a11b8 | import copy
import datetime
import inspect
from decimal import Decimal
from django.core.exceptions import EmptyResultSet, FieldError
from django.db import NotSupportedError, connection
from django.db.models import fields
from django.db.models.constants import LOOKUP_SEP
from django.db.models.query_utils import Q
from django.utils.deconstruct import deconstructible
from django.utils.functional import cached_property
from django.utils.hashable import make_hashable
class SQLiteNumericMixin:
"""
Some expressions with output_field=DecimalField() must be cast to
numeric to be properly filtered.
"""
def as_sqlite(self, compiler, connection, **extra_context):
sql, params = self.as_sql(compiler, connection, **extra_context)
try:
if self.output_field.get_internal_type() == 'DecimalField':
sql = 'CAST(%s AS NUMERIC)' % sql
except FieldError:
pass
return sql, params
class Combinable:
"""
Provide the ability to combine one or two objects with
some connector. For example F('foo') + F('bar').
"""
# Arithmetic connectors
ADD = '+'
SUB = '-'
MUL = '*'
DIV = '/'
POW = '^'
# The following is a quoted % operator - it is quoted because it can be
# used in strings that also have parameter substitution.
MOD = '%%'
# Bitwise operators - note that these are generated by .bitand()
# and .bitor(), the '&' and '|' are reserved for boolean operator
# usage.
BITAND = '&'
BITOR = '|'
BITLEFTSHIFT = '<<'
BITRIGHTSHIFT = '>>'
BITXOR = '#'
def _combine(self, other, connector, reversed):
if not hasattr(other, 'resolve_expression'):
# everything must be resolvable to an expression
if isinstance(other, datetime.timedelta):
other = DurationValue(other, output_field=fields.DurationField())
else:
other = Value(other)
if reversed:
return CombinedExpression(other, connector, self)
return CombinedExpression(self, connector, other)
#############
# OPERATORS #
#############
def __neg__(self):
return self._combine(-1, self.MUL, False)
def __add__(self, other):
return self._combine(other, self.ADD, False)
def __sub__(self, other):
return self._combine(other, self.SUB, False)
def __mul__(self, other):
return self._combine(other, self.MUL, False)
def __truediv__(self, other):
return self._combine(other, self.DIV, False)
def __mod__(self, other):
return self._combine(other, self.MOD, False)
def __pow__(self, other):
return self._combine(other, self.POW, False)
def __and__(self, other):
if getattr(self, 'conditional', False) and getattr(other, 'conditional', False):
return Q(self) & Q(other)
raise NotImplementedError(
"Use .bitand() and .bitor() for bitwise logical operations."
)
def bitand(self, other):
return self._combine(other, self.BITAND, False)
def bitleftshift(self, other):
return self._combine(other, self.BITLEFTSHIFT, False)
def bitrightshift(self, other):
return self._combine(other, self.BITRIGHTSHIFT, False)
def bitxor(self, other):
return self._combine(other, self.BITXOR, False)
def __or__(self, other):
if getattr(self, 'conditional', False) and getattr(other, 'conditional', False):
return Q(self) | Q(other)
raise NotImplementedError(
"Use .bitand() and .bitor() for bitwise logical operations."
)
def bitor(self, other):
return self._combine(other, self.BITOR, False)
def __radd__(self, other):
return self._combine(other, self.ADD, True)
def __rsub__(self, other):
return self._combine(other, self.SUB, True)
def __rmul__(self, other):
return self._combine(other, self.MUL, True)
def __rtruediv__(self, other):
return self._combine(other, self.DIV, True)
def __rmod__(self, other):
return self._combine(other, self.MOD, True)
def __rpow__(self, other):
return self._combine(other, self.POW, True)
def __rand__(self, other):
raise NotImplementedError(
"Use .bitand() and .bitor() for bitwise logical operations."
)
def __ror__(self, other):
raise NotImplementedError(
"Use .bitand() and .bitor() for bitwise logical operations."
)
@deconstructible
class BaseExpression:
"""Base class for all query expressions."""
# aggregate specific fields
is_summary = False
_output_field_resolved_to_none = False
# Can the expression be used in a WHERE clause?
filterable = True
# Can the expression can be used as a source expression in Window?
window_compatible = False
def __init__(self, output_field=None):
if output_field is not None:
self.output_field = output_field
def __getstate__(self):
state = self.__dict__.copy()
state.pop('convert_value', None)
return state
def get_db_converters(self, connection):
return (
[]
if self.convert_value is self._convert_value_noop else
[self.convert_value]
) + self.output_field.get_db_converters(connection)
def get_source_expressions(self):
return []
def set_source_expressions(self, exprs):
assert not exprs
def _parse_expressions(self, *expressions):
return [
arg if hasattr(arg, 'resolve_expression') else (
F(arg) if isinstance(arg, str) else Value(arg)
) for arg in expressions
]
def as_sql(self, compiler, connection):
"""
Responsible for returning a (sql, [params]) tuple to be included
in the current query.
Different backends can provide their own implementation, by
providing an `as_{vendor}` method and patching the Expression:
```
def override_as_sql(self, compiler, connection):
# custom logic
return super().as_sql(compiler, connection)
setattr(Expression, 'as_' + connection.vendor, override_as_sql)
```
Arguments:
* compiler: the query compiler responsible for generating the query.
Must have a compile method, returning a (sql, [params]) tuple.
Calling compiler(value) will return a quoted `value`.
* connection: the database connection used for the current query.
Return: (sql, params)
Where `sql` is a string containing ordered sql parameters to be
replaced with the elements of the list `params`.
"""
raise NotImplementedError("Subclasses must implement as_sql()")
@cached_property
def contains_aggregate(self):
return any(expr and expr.contains_aggregate for expr in self.get_source_expressions())
@cached_property
def contains_over_clause(self):
return any(expr and expr.contains_over_clause for expr in self.get_source_expressions())
@cached_property
def contains_column_references(self):
return any(expr and expr.contains_column_references for expr in self.get_source_expressions())
def resolve_expression(self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False):
"""
Provide the chance to do any preprocessing or validation before being
added to the query.
Arguments:
* query: the backend query implementation
* allow_joins: boolean allowing or denying use of joins
in this query
* reuse: a set of reusable joins for multijoins
* summarize: a terminal aggregate clause
* for_save: whether this expression about to be used in a save or update
Return: an Expression to be added to the query.
"""
c = self.copy()
c.is_summary = summarize
c.set_source_expressions([
expr.resolve_expression(query, allow_joins, reuse, summarize)
if expr else None
for expr in c.get_source_expressions()
])
return c
@property
def conditional(self):
return isinstance(self.output_field, fields.BooleanField)
@property
def field(self):
return self.output_field
@cached_property
def output_field(self):
"""Return the output type of this expressions."""
output_field = self._resolve_output_field()
if output_field is None:
self._output_field_resolved_to_none = True
raise FieldError('Cannot resolve expression type, unknown output_field')
return output_field
@cached_property
def _output_field_or_none(self):
"""
Return the output field of this expression, or None if
_resolve_output_field() didn't return an output type.
"""
try:
return self.output_field
except FieldError:
if not self._output_field_resolved_to_none:
raise
def _resolve_output_field(self):
"""
Attempt to infer the output type of the expression. If the output
fields of all source fields match then, simply infer the same type
here. This isn't always correct, but it makes sense most of the time.
Consider the difference between `2 + 2` and `2 / 3`. Inferring
the type here is a convenience for the common case. The user should
supply their own output_field with more complex computations.
If a source's output field resolves to None, exclude it from this check.
If all sources are None, then an error is raised higher up the stack in
the output_field property.
"""
sources_iter = (source for source in self.get_source_fields() if source is not None)
for output_field in sources_iter:
for source in sources_iter:
if not isinstance(output_field, source.__class__):
raise FieldError(
'Expression contains mixed types: %s, %s. You must '
'set output_field.' % (
output_field.__class__.__name__,
source.__class__.__name__,
)
)
return output_field
@staticmethod
def _convert_value_noop(value, expression, connection):
return value
@cached_property
def convert_value(self):
"""
Expressions provide their own converters because users have the option
of manually specifying the output_field which may be a different type
from the one the database returns.
"""
field = self.output_field
internal_type = field.get_internal_type()
if internal_type == 'FloatField':
return lambda value, expression, connection: None if value is None else float(value)
elif internal_type.endswith('IntegerField'):
return lambda value, expression, connection: None if value is None else int(value)
elif internal_type == 'DecimalField':
return lambda value, expression, connection: None if value is None else Decimal(value)
return self._convert_value_noop
def get_lookup(self, lookup):
return self.output_field.get_lookup(lookup)
def get_transform(self, name):
return self.output_field.get_transform(name)
def relabeled_clone(self, change_map):
clone = self.copy()
clone.set_source_expressions([
e.relabeled_clone(change_map) if e is not None else None
for e in self.get_source_expressions()
])
return clone
def copy(self):
return copy.copy(self)
def get_group_by_cols(self, alias=None):
if not self.contains_aggregate:
return [self]
cols = []
for source in self.get_source_expressions():
cols.extend(source.get_group_by_cols())
return cols
def get_source_fields(self):
"""Return the underlying field types used by this aggregate."""
return [e._output_field_or_none for e in self.get_source_expressions()]
def asc(self, **kwargs):
return OrderBy(self, **kwargs)
def desc(self, **kwargs):
return OrderBy(self, descending=True, **kwargs)
def reverse_ordering(self):
return self
def flatten(self):
"""
Recursively yield this expression and all subexpressions, in
depth-first order.
"""
yield self
for expr in self.get_source_expressions():
if expr:
yield from expr.flatten()
def select_format(self, compiler, sql, params):
"""
Custom format for select clauses. For example, EXISTS expressions need
to be wrapped in CASE WHEN on Oracle.
"""
return self.output_field.select_format(compiler, sql, params)
@cached_property
def identity(self):
constructor_signature = inspect.signature(self.__init__)
args, kwargs = self._constructor_args
signature = constructor_signature.bind_partial(*args, **kwargs)
signature.apply_defaults()
arguments = signature.arguments.items()
identity = [self.__class__]
for arg, value in arguments:
if isinstance(value, fields.Field):
if value.name and value.model:
value = (value.model._meta.label, value.name)
else:
value = type(value)
else:
value = make_hashable(value)
identity.append((arg, value))
return tuple(identity)
def __eq__(self, other):
if not isinstance(other, BaseExpression):
return NotImplemented
return other.identity == self.identity
def __hash__(self):
return hash(self.identity)
class Expression(BaseExpression, Combinable):
"""An expression that can be combined with other expressions."""
pass
class CombinedExpression(SQLiteNumericMixin, Expression):
def __init__(self, lhs, connector, rhs, output_field=None):
super().__init__(output_field=output_field)
self.connector = connector
self.lhs = lhs
self.rhs = rhs
def __repr__(self):
return "<{}: {}>".format(self.__class__.__name__, self)
def __str__(self):
return "{} {} {}".format(self.lhs, self.connector, self.rhs)
def get_source_expressions(self):
return [self.lhs, self.rhs]
def set_source_expressions(self, exprs):
self.lhs, self.rhs = exprs
def as_sql(self, compiler, connection):
try:
lhs_output = self.lhs.output_field
except FieldError:
lhs_output = None
try:
rhs_output = self.rhs.output_field
except FieldError:
rhs_output = None
if (not connection.features.has_native_duration_field and
((lhs_output and lhs_output.get_internal_type() == 'DurationField') or
(rhs_output and rhs_output.get_internal_type() == 'DurationField'))):
return DurationExpression(self.lhs, self.connector, self.rhs).as_sql(compiler, connection)
if (lhs_output and rhs_output and self.connector == self.SUB and
lhs_output.get_internal_type() in {'DateField', 'DateTimeField', 'TimeField'} and
lhs_output.get_internal_type() == rhs_output.get_internal_type()):
return TemporalSubtraction(self.lhs, self.rhs).as_sql(compiler, connection)
expressions = []
expression_params = []
sql, params = compiler.compile(self.lhs)
expressions.append(sql)
expression_params.extend(params)
sql, params = compiler.compile(self.rhs)
expressions.append(sql)
expression_params.extend(params)
# order of precedence
expression_wrapper = '(%s)'
sql = connection.ops.combine_expression(self.connector, expressions)
return expression_wrapper % sql, expression_params
def resolve_expression(self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False):
c = self.copy()
c.is_summary = summarize
c.lhs = c.lhs.resolve_expression(query, allow_joins, reuse, summarize, for_save)
c.rhs = c.rhs.resolve_expression(query, allow_joins, reuse, summarize, for_save)
return c
class DurationExpression(CombinedExpression):
def compile(self, side, compiler, connection):
if not isinstance(side, DurationValue):
try:
output = side.output_field
except FieldError:
pass
else:
if output.get_internal_type() == 'DurationField':
sql, params = compiler.compile(side)
return connection.ops.format_for_duration_arithmetic(sql), params
return compiler.compile(side)
def as_sql(self, compiler, connection):
connection.ops.check_expression_support(self)
expressions = []
expression_params = []
sql, params = self.compile(self.lhs, compiler, connection)
expressions.append(sql)
expression_params.extend(params)
sql, params = self.compile(self.rhs, compiler, connection)
expressions.append(sql)
expression_params.extend(params)
# order of precedence
expression_wrapper = '(%s)'
sql = connection.ops.combine_duration_expression(self.connector, expressions)
return expression_wrapper % sql, expression_params
class TemporalSubtraction(CombinedExpression):
output_field = fields.DurationField()
def __init__(self, lhs, rhs):
super().__init__(lhs, self.SUB, rhs)
def as_sql(self, compiler, connection):
connection.ops.check_expression_support(self)
lhs = compiler.compile(self.lhs)
rhs = compiler.compile(self.rhs)
return connection.ops.subtract_temporals(self.lhs.output_field.get_internal_type(), lhs, rhs)
@deconstructible
class F(Combinable):
"""An object capable of resolving references to existing query objects."""
def __init__(self, name):
"""
Arguments:
* name: the name of the field this expression references
"""
self.name = name
def __repr__(self):
return "{}({})".format(self.__class__.__name__, self.name)
def resolve_expression(self, query=None, allow_joins=True, reuse=None,
summarize=False, for_save=False):
return query.resolve_ref(self.name, allow_joins, reuse, summarize)
def asc(self, **kwargs):
return OrderBy(self, **kwargs)
def desc(self, **kwargs):
return OrderBy(self, descending=True, **kwargs)
def __eq__(self, other):
return self.__class__ == other.__class__ and self.name == other.name
def __hash__(self):
return hash(self.name)
class ResolvedOuterRef(F):
"""
An object that contains a reference to an outer query.
In this case, the reference to the outer query has been resolved because
the inner query has been used as a subquery.
"""
contains_aggregate = False
def as_sql(self, *args, **kwargs):
raise ValueError(
'This queryset contains a reference to an outer query and may '
'only be used in a subquery.'
)
def resolve_expression(self, *args, **kwargs):
col = super().resolve_expression(*args, **kwargs)
# FIXME: Rename possibly_multivalued to multivalued and fix detection
# for non-multivalued JOINs (e.g. foreign key fields). This should take
# into account only many-to-many and one-to-many relationships.
col.possibly_multivalued = LOOKUP_SEP in self.name
return col
def relabeled_clone(self, relabels):
return self
def get_group_by_cols(self, alias=None):
return []
class OuterRef(F):
def resolve_expression(self, *args, **kwargs):
if isinstance(self.name, self.__class__):
return self.name
return ResolvedOuterRef(self.name)
def relabeled_clone(self, relabels):
return self
class Func(SQLiteNumericMixin, Expression):
"""An SQL function call."""
function = None
template = '%(function)s(%(expressions)s)'
arg_joiner = ', '
arity = None # The number of arguments the function accepts.
def __init__(self, *expressions, output_field=None, **extra):
if self.arity is not None and len(expressions) != self.arity:
raise TypeError(
"'%s' takes exactly %s %s (%s given)" % (
self.__class__.__name__,
self.arity,
"argument" if self.arity == 1 else "arguments",
len(expressions),
)
)
super().__init__(output_field=output_field)
self.source_expressions = self._parse_expressions(*expressions)
self.extra = extra
def __repr__(self):
args = self.arg_joiner.join(str(arg) for arg in self.source_expressions)
extra = {**self.extra, **self._get_repr_options()}
if extra:
extra = ', '.join(str(key) + '=' + str(val) for key, val in sorted(extra.items()))
return "{}({}, {})".format(self.__class__.__name__, args, extra)
return "{}({})".format(self.__class__.__name__, args)
def _get_repr_options(self):
"""Return a dict of extra __init__() options to include in the repr."""
return {}
def get_source_expressions(self):
return self.source_expressions
def set_source_expressions(self, exprs):
self.source_expressions = exprs
def resolve_expression(self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False):
c = self.copy()
c.is_summary = summarize
for pos, arg in enumerate(c.source_expressions):
c.source_expressions[pos] = arg.resolve_expression(query, allow_joins, reuse, summarize, for_save)
return c
def as_sql(self, compiler, connection, function=None, template=None, arg_joiner=None, **extra_context):
connection.ops.check_expression_support(self)
sql_parts = []
params = []
for arg in self.source_expressions:
arg_sql, arg_params = compiler.compile(arg)
sql_parts.append(arg_sql)
params.extend(arg_params)
data = {**self.extra, **extra_context}
# Use the first supplied value in this order: the parameter to this
# method, a value supplied in __init__()'s **extra (the value in
# `data`), or the value defined on the class.
if function is not None:
data['function'] = function
else:
data.setdefault('function', self.function)
template = template or data.get('template', self.template)
arg_joiner = arg_joiner or data.get('arg_joiner', self.arg_joiner)
data['expressions'] = data['field'] = arg_joiner.join(sql_parts)
return template % data, params
def copy(self):
copy = super().copy()
copy.source_expressions = self.source_expressions[:]
copy.extra = self.extra.copy()
return copy
class Value(Expression):
"""Represent a wrapped value as a node within an expression."""
def __init__(self, value, output_field=None):
"""
Arguments:
* value: the value this expression represents. The value will be
added into the sql parameter list and properly quoted.
* output_field: an instance of the model field type that this
expression will return, such as IntegerField() or CharField().
"""
super().__init__(output_field=output_field)
self.value = value
def __repr__(self):
return "{}({})".format(self.__class__.__name__, self.value)
def as_sql(self, compiler, connection):
connection.ops.check_expression_support(self)
val = self.value
output_field = self._output_field_or_none
if output_field is not None:
if self.for_save:
val = output_field.get_db_prep_save(val, connection=connection)
else:
val = output_field.get_db_prep_value(val, connection=connection)
if hasattr(output_field, 'get_placeholder'):
return output_field.get_placeholder(val, compiler, connection), [val]
if val is None:
# cx_Oracle does not always convert None to the appropriate
# NULL type (like in case expressions using numbers), so we
# use a literal SQL NULL
return 'NULL', []
return '%s', [val]
def resolve_expression(self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False):
c = super().resolve_expression(query, allow_joins, reuse, summarize, for_save)
c.for_save = for_save
return c
def get_group_by_cols(self, alias=None):
return []
class DurationValue(Value):
def as_sql(self, compiler, connection):
connection.ops.check_expression_support(self)
if connection.features.has_native_duration_field:
return super().as_sql(compiler, connection)
return connection.ops.date_interval_sql(self.value), []
class RawSQL(Expression):
def __init__(self, sql, params, output_field=None):
if output_field is None:
output_field = fields.Field()
self.sql, self.params = sql, params
super().__init__(output_field=output_field)
def __repr__(self):
return "{}({}, {})".format(self.__class__.__name__, self.sql, self.params)
def as_sql(self, compiler, connection):
return '(%s)' % self.sql, self.params
def get_group_by_cols(self, alias=None):
return [self]
def resolve_expression(self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False):
# Resolve parents fields used in raw SQL.
for parent in query.model._meta.get_parent_list():
for parent_field in parent._meta.local_fields:
_, column_name = parent_field.get_attname_column()
if column_name.lower() in self.sql.lower():
query.resolve_ref(parent_field.name, allow_joins, reuse, summarize)
break
return super().resolve_expression(query, allow_joins, reuse, summarize, for_save)
class Star(Expression):
def __repr__(self):
return "'*'"
def as_sql(self, compiler, connection):
return '*', []
class Random(Expression):
output_field = fields.FloatField()
def __repr__(self):
return "Random()"
def as_sql(self, compiler, connection):
return connection.ops.random_function_sql(), []
class Col(Expression):
contains_column_references = True
possibly_multivalued = False
def __init__(self, alias, target, output_field=None):
if output_field is None:
output_field = target
super().__init__(output_field=output_field)
self.alias, self.target = alias, target
def __repr__(self):
alias, target = self.alias, self.target
identifiers = (alias, str(target)) if alias else (str(target),)
return '{}({})'.format(self.__class__.__name__, ', '.join(identifiers))
def as_sql(self, compiler, connection):
alias, column = self.alias, self.target.column
identifiers = (alias, column) if alias else (column,)
sql = '.'.join(map(compiler.quote_name_unless_alias, identifiers))
return sql, []
def relabeled_clone(self, relabels):
if self.alias is None:
return self
return self.__class__(relabels.get(self.alias, self.alias), self.target, self.output_field)
def get_group_by_cols(self, alias=None):
return [self]
def get_db_converters(self, connection):
if self.target == self.output_field:
return self.output_field.get_db_converters(connection)
return (self.output_field.get_db_converters(connection) +
self.target.get_db_converters(connection))
class Ref(Expression):
"""
Reference to column alias of the query. For example, Ref('sum_cost') in
qs.annotate(sum_cost=Sum('cost')) query.
"""
def __init__(self, refs, source):
super().__init__()
self.refs, self.source = refs, source
def __repr__(self):
return "{}({}, {})".format(self.__class__.__name__, self.refs, self.source)
def get_source_expressions(self):
return [self.source]
def set_source_expressions(self, exprs):
self.source, = exprs
def resolve_expression(self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False):
# The sub-expression `source` has already been resolved, as this is
# just a reference to the name of `source`.
return self
def relabeled_clone(self, relabels):
return self
def as_sql(self, compiler, connection):
return connection.ops.quote_name(self.refs), []
def get_group_by_cols(self, alias=None):
return [self]
class ExpressionList(Func):
"""
An expression containing multiple expressions. Can be used to provide a
list of expressions as an argument to another expression, like an
ordering clause.
"""
template = '%(expressions)s'
def __init__(self, *expressions, **extra):
if not expressions:
raise ValueError('%s requires at least one expression.' % self.__class__.__name__)
super().__init__(*expressions, **extra)
def __str__(self):
return self.arg_joiner.join(str(arg) for arg in self.source_expressions)
class ExpressionWrapper(Expression):
"""
An expression that can wrap another expression so that it can provide
extra context to the inner expression, such as the output_field.
"""
def __init__(self, expression, output_field):
super().__init__(output_field=output_field)
self.expression = expression
def set_source_expressions(self, exprs):
self.expression = exprs[0]
def get_source_expressions(self):
return [self.expression]
def as_sql(self, compiler, connection):
return self.expression.as_sql(compiler, connection)
def __repr__(self):
return "{}({})".format(self.__class__.__name__, self.expression)
class When(Expression):
template = 'WHEN %(condition)s THEN %(result)s'
# This isn't a complete conditional expression, must be used in Case().
conditional = False
def __init__(self, condition=None, then=None, **lookups):
if lookups and condition is None:
condition, lookups = Q(**lookups), None
if condition is None or not getattr(condition, 'conditional', False) or lookups:
raise TypeError(
'When() supports a Q object, a boolean expression, or lookups '
'as a condition.'
)
if isinstance(condition, Q) and not condition:
raise ValueError("An empty Q() can't be used as a When() condition.")
super().__init__(output_field=None)
self.condition = condition
self.result = self._parse_expressions(then)[0]
def __str__(self):
return "WHEN %r THEN %r" % (self.condition, self.result)
def __repr__(self):
return "<%s: %s>" % (self.__class__.__name__, self)
def get_source_expressions(self):
return [self.condition, self.result]
def set_source_expressions(self, exprs):
self.condition, self.result = exprs
def get_source_fields(self):
# We're only interested in the fields of the result expressions.
return [self.result._output_field_or_none]
def resolve_expression(self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False):
c = self.copy()
c.is_summary = summarize
if hasattr(c.condition, 'resolve_expression'):
c.condition = c.condition.resolve_expression(query, allow_joins, reuse, summarize, False)
c.result = c.result.resolve_expression(query, allow_joins, reuse, summarize, for_save)
return c
def as_sql(self, compiler, connection, template=None, **extra_context):
connection.ops.check_expression_support(self)
template_params = extra_context
sql_params = []
condition_sql, condition_params = compiler.compile(self.condition)
template_params['condition'] = condition_sql
sql_params.extend(condition_params)
result_sql, result_params = compiler.compile(self.result)
template_params['result'] = result_sql
sql_params.extend(result_params)
template = template or self.template
return template % template_params, sql_params
def get_group_by_cols(self, alias=None):
# This is not a complete expression and cannot be used in GROUP BY.
cols = []
for source in self.get_source_expressions():
cols.extend(source.get_group_by_cols())
return cols
class Case(Expression):
"""
An SQL searched CASE expression:
CASE
WHEN n > 0
THEN 'positive'
WHEN n < 0
THEN 'negative'
ELSE 'zero'
END
"""
template = 'CASE %(cases)s ELSE %(default)s END'
case_joiner = ' '
def __init__(self, *cases, default=None, output_field=None, **extra):
if not all(isinstance(case, When) for case in cases):
raise TypeError("Positional arguments must all be When objects.")
super().__init__(output_field)
self.cases = list(cases)
self.default = self._parse_expressions(default)[0]
self.extra = extra
def __str__(self):
return "CASE %s, ELSE %r" % (', '.join(str(c) for c in self.cases), self.default)
def __repr__(self):
return "<%s: %s>" % (self.__class__.__name__, self)
def get_source_expressions(self):
return self.cases + [self.default]
def set_source_expressions(self, exprs):
*self.cases, self.default = exprs
def resolve_expression(self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False):
c = self.copy()
c.is_summary = summarize
for pos, case in enumerate(c.cases):
c.cases[pos] = case.resolve_expression(query, allow_joins, reuse, summarize, for_save)
c.default = c.default.resolve_expression(query, allow_joins, reuse, summarize, for_save)
return c
def copy(self):
c = super().copy()
c.cases = c.cases[:]
return c
def as_sql(self, compiler, connection, template=None, case_joiner=None, **extra_context):
connection.ops.check_expression_support(self)
if not self.cases:
return compiler.compile(self.default)
template_params = {**self.extra, **extra_context}
case_parts = []
sql_params = []
for case in self.cases:
try:
case_sql, case_params = compiler.compile(case)
except EmptyResultSet:
continue
case_parts.append(case_sql)
sql_params.extend(case_params)
default_sql, default_params = compiler.compile(self.default)
if not case_parts:
return default_sql, default_params
case_joiner = case_joiner or self.case_joiner
template_params['cases'] = case_joiner.join(case_parts)
template_params['default'] = default_sql
sql_params.extend(default_params)
template = template or template_params.get('template', self.template)
sql = template % template_params
if self._output_field_or_none is not None:
sql = connection.ops.unification_cast_sql(self.output_field) % sql
return sql, sql_params
class Subquery(Expression):
"""
An explicit subquery. It may contain OuterRef() references to the outer
query which will be resolved when it is applied to that query.
"""
template = '(%(subquery)s)'
contains_aggregate = False
def __init__(self, queryset, output_field=None, **extra):
self.query = queryset.query
self.extra = extra
super().__init__(output_field)
def __getstate__(self):
state = super().__getstate__()
state.pop('_constructor_args', None)
return state
def get_source_expressions(self):
return [self.query]
def set_source_expressions(self, exprs):
self.query = exprs[0]
def _resolve_output_field(self):
return self.query.output_field
def copy(self):
clone = super().copy()
clone.query = clone.query.clone()
return clone
@property
def external_aliases(self):
return self.query.external_aliases
def as_sql(self, compiler, connection, template=None, **extra_context):
connection.ops.check_expression_support(self)
template_params = {**self.extra, **extra_context}
subquery_sql, sql_params = self.query.as_sql(compiler, connection)
template_params['subquery'] = subquery_sql[1:-1]
template = template or template_params.get('template', self.template)
sql = template % template_params
return sql, sql_params
def get_group_by_cols(self, alias=None):
if alias:
return [Ref(alias, self)]
external_cols = self.query.get_external_cols()
if any(col.possibly_multivalued for col in external_cols):
return [self]
return external_cols
class Exists(Subquery):
template = 'EXISTS(%(subquery)s)'
output_field = fields.BooleanField()
def __init__(self, queryset, negated=False, **kwargs):
# As a performance optimization, remove ordering since EXISTS doesn't
# care about it, just whether or not a row matches.
queryset = queryset.order_by()
self.negated = negated
super().__init__(queryset, **kwargs)
def __invert__(self):
clone = self.copy()
clone.negated = not self.negated
return clone
def as_sql(self, compiler, connection, template=None, **extra_context):
sql, params = super().as_sql(compiler, connection, template, **extra_context)
if self.negated:
sql = 'NOT {}'.format(sql)
return sql, params
def select_format(self, compiler, sql, params):
# Wrap EXISTS() with a CASE WHEN expression if a database backend
# (e.g. Oracle) doesn't support boolean expression in the SELECT list.
if not compiler.connection.features.supports_boolean_expr_in_select_clause:
sql = 'CASE WHEN {} THEN 1 ELSE 0 END'.format(sql)
return sql, params
class OrderBy(BaseExpression):
template = '%(expression)s %(ordering)s'
conditional = False
def __init__(self, expression, descending=False, nulls_first=False, nulls_last=False):
if nulls_first and nulls_last:
raise ValueError('nulls_first and nulls_last are mutually exclusive')
self.nulls_first = nulls_first
self.nulls_last = nulls_last
self.descending = descending
if not hasattr(expression, 'resolve_expression'):
raise ValueError('expression must be an expression type')
self.expression = expression
def __repr__(self):
return "{}({}, descending={})".format(
self.__class__.__name__, self.expression, self.descending)
def set_source_expressions(self, exprs):
self.expression = exprs[0]
def get_source_expressions(self):
return [self.expression]
def as_sql(self, compiler, connection, template=None, **extra_context):
template = template or self.template
if connection.features.supports_order_by_nulls_modifier:
if self.nulls_last:
template = '%s NULLS LAST' % template
elif self.nulls_first:
template = '%s NULLS FIRST' % template
else:
if self.nulls_last and not (
self.descending and connection.features.order_by_nulls_first
):
template = '%%(expression)s IS NULL, %s' % template
elif self.nulls_first and not (
not self.descending and connection.features.order_by_nulls_first
):
template = '%%(expression)s IS NOT NULL, %s' % template
connection.ops.check_expression_support(self)
expression_sql, params = compiler.compile(self.expression)
placeholders = {
'expression': expression_sql,
'ordering': 'DESC' if self.descending else 'ASC',
**extra_context,
}
template = template or self.template
params *= template.count('%(expression)s')
return (template % placeholders).rstrip(), params
def as_oracle(self, compiler, connection):
# Oracle doesn't allow ORDER BY EXISTS() unless it's wrapped in
# a CASE WHEN.
if isinstance(self.expression, Exists):
copy = self.copy()
copy.expression = Case(
When(self.expression, then=True),
default=False,
output_field=fields.BooleanField(),
)
return copy.as_sql(compiler, connection)
return self.as_sql(compiler, connection)
def get_group_by_cols(self, alias=None):
cols = []
for source in self.get_source_expressions():
cols.extend(source.get_group_by_cols())
return cols
def reverse_ordering(self):
self.descending = not self.descending
if self.nulls_first or self.nulls_last:
self.nulls_first = not self.nulls_first
self.nulls_last = not self.nulls_last
return self
def asc(self):
self.descending = False
def desc(self):
self.descending = True
class Window(Expression):
template = '%(expression)s OVER (%(window)s)'
# Although the main expression may either be an aggregate or an
# expression with an aggregate function, the GROUP BY that will
# be introduced in the query as a result is not desired.
contains_aggregate = False
contains_over_clause = True
filterable = False
def __init__(self, expression, partition_by=None, order_by=None, frame=None, output_field=None):
self.partition_by = partition_by
self.order_by = order_by
self.frame = frame
if not getattr(expression, 'window_compatible', False):
raise ValueError(
"Expression '%s' isn't compatible with OVER clauses." %
expression.__class__.__name__
)
if self.partition_by is not None:
if not isinstance(self.partition_by, (tuple, list)):
self.partition_by = (self.partition_by,)
self.partition_by = ExpressionList(*self.partition_by)
if self.order_by is not None:
if isinstance(self.order_by, (list, tuple)):
self.order_by = ExpressionList(*self.order_by)
elif not isinstance(self.order_by, BaseExpression):
raise ValueError(
'order_by must be either an Expression or a sequence of '
'expressions.'
)
super().__init__(output_field=output_field)
self.source_expression = self._parse_expressions(expression)[0]
def _resolve_output_field(self):
return self.source_expression.output_field
def get_source_expressions(self):
return [self.source_expression, self.partition_by, self.order_by, self.frame]
def set_source_expressions(self, exprs):
self.source_expression, self.partition_by, self.order_by, self.frame = exprs
def as_sql(self, compiler, connection, template=None):
connection.ops.check_expression_support(self)
if not connection.features.supports_over_clause:
raise NotSupportedError('This backend does not support window expressions.')
expr_sql, params = compiler.compile(self.source_expression)
window_sql, window_params = [], []
if self.partition_by is not None:
sql_expr, sql_params = self.partition_by.as_sql(
compiler=compiler, connection=connection,
template='PARTITION BY %(expressions)s',
)
window_sql.extend(sql_expr)
window_params.extend(sql_params)
if self.order_by is not None:
window_sql.append(' ORDER BY ')
order_sql, order_params = compiler.compile(self.order_by)
window_sql.extend(order_sql)
window_params.extend(order_params)
if self.frame:
frame_sql, frame_params = compiler.compile(self.frame)
window_sql.append(' ' + frame_sql)
window_params.extend(frame_params)
params.extend(window_params)
template = template or self.template
return template % {
'expression': expr_sql,
'window': ''.join(window_sql).strip()
}, params
def __str__(self):
return '{} OVER ({}{}{})'.format(
str(self.source_expression),
'PARTITION BY ' + str(self.partition_by) if self.partition_by else '',
'ORDER BY ' + str(self.order_by) if self.order_by else '',
str(self.frame or ''),
)
def __repr__(self):
return '<%s: %s>' % (self.__class__.__name__, self)
def get_group_by_cols(self, alias=None):
return []
class WindowFrame(Expression):
"""
Model the frame clause in window expressions. There are two types of frame
clauses which are subclasses, however, all processing and validation (by no
means intended to be complete) is done here. Thus, providing an end for a
frame is optional (the default is UNBOUNDED FOLLOWING, which is the last
row in the frame).
"""
template = '%(frame_type)s BETWEEN %(start)s AND %(end)s'
def __init__(self, start=None, end=None):
self.start = Value(start)
self.end = Value(end)
def set_source_expressions(self, exprs):
self.start, self.end = exprs
def get_source_expressions(self):
return [self.start, self.end]
def as_sql(self, compiler, connection):
connection.ops.check_expression_support(self)
start, end = self.window_frame_start_end(connection, self.start.value, self.end.value)
return self.template % {
'frame_type': self.frame_type,
'start': start,
'end': end,
}, []
def __repr__(self):
return '<%s: %s>' % (self.__class__.__name__, self)
def get_group_by_cols(self, alias=None):
return []
def __str__(self):
if self.start.value is not None and self.start.value < 0:
start = '%d %s' % (abs(self.start.value), connection.ops.PRECEDING)
elif self.start.value is not None and self.start.value == 0:
start = connection.ops.CURRENT_ROW
else:
start = connection.ops.UNBOUNDED_PRECEDING
if self.end.value is not None and self.end.value > 0:
end = '%d %s' % (self.end.value, connection.ops.FOLLOWING)
elif self.end.value is not None and self.end.value == 0:
end = connection.ops.CURRENT_ROW
else:
end = connection.ops.UNBOUNDED_FOLLOWING
return self.template % {
'frame_type': self.frame_type,
'start': start,
'end': end,
}
def window_frame_start_end(self, connection, start, end):
raise NotImplementedError('Subclasses must implement window_frame_start_end().')
class RowRange(WindowFrame):
frame_type = 'ROWS'
def window_frame_start_end(self, connection, start, end):
return connection.ops.window_frame_rows_start_end(start, end)
class ValueRange(WindowFrame):
frame_type = 'RANGE'
def window_frame_start_end(self, connection, start, end):
return connection.ops.window_frame_range_start_end(start, end)
|
0cc95a388bc2a823831a9277ae6a8b201c7d90cd7279f830e22f88a438bba4e0 | import operator
from collections import Counter, defaultdict
from functools import partial, reduce
from itertools import chain
from operator import attrgetter
from django.db import IntegrityError, connections, transaction
from django.db.models import query_utils, signals, sql
class ProtectedError(IntegrityError):
def __init__(self, msg, protected_objects):
self.protected_objects = protected_objects
super().__init__(msg, protected_objects)
class RestrictedError(IntegrityError):
def __init__(self, msg, restricted_objects):
self.restricted_objects = restricted_objects
super().__init__(msg, restricted_objects)
def CASCADE(collector, field, sub_objs, using):
collector.collect(
sub_objs, source=field.remote_field.model, source_attr=field.name,
nullable=field.null, fail_on_restricted=False,
)
if field.null and not connections[using].features.can_defer_constraint_checks:
collector.add_field_update(field, None, sub_objs)
def PROTECT(collector, field, sub_objs, using):
raise ProtectedError(
"Cannot delete some instances of model '%s' because they are "
"referenced through a protected foreign key: '%s.%s'" % (
field.remote_field.model.__name__, sub_objs[0].__class__.__name__, field.name
),
sub_objs
)
def RESTRICT(collector, field, sub_objs, using):
collector.add_restricted_objects(field, sub_objs)
collector.add_dependency(field.remote_field.model, field.model)
def SET(value):
if callable(value):
def set_on_delete(collector, field, sub_objs, using):
collector.add_field_update(field, value(), sub_objs)
else:
def set_on_delete(collector, field, sub_objs, using):
collector.add_field_update(field, value, sub_objs)
set_on_delete.deconstruct = lambda: ('django.db.models.SET', (value,), {})
return set_on_delete
def SET_NULL(collector, field, sub_objs, using):
collector.add_field_update(field, None, sub_objs)
def SET_DEFAULT(collector, field, sub_objs, using):
collector.add_field_update(field, field.get_default(), sub_objs)
def DO_NOTHING(collector, field, sub_objs, using):
pass
def get_candidate_relations_to_delete(opts):
# The candidate relations are the ones that come from N-1 and 1-1 relations.
# N-N (i.e., many-to-many) relations aren't candidates for deletion.
return (
f for f in opts.get_fields(include_hidden=True)
if f.auto_created and not f.concrete and (f.one_to_one or f.one_to_many)
)
class Collector:
def __init__(self, using):
self.using = using
# Initially, {model: {instances}}, later values become lists.
self.data = defaultdict(set)
# {model: {(field, value): {instances}}}
self.field_updates = defaultdict(partial(defaultdict, set))
# {model: {field: {instances}}}
self.restricted_objects = defaultdict(partial(defaultdict, set))
# fast_deletes is a list of queryset-likes that can be deleted without
# fetching the objects into memory.
self.fast_deletes = []
# Tracks deletion-order dependency for databases without transactions
# or ability to defer constraint checks. Only concrete model classes
# should be included, as the dependencies exist only between actual
# database tables; proxy models are represented here by their concrete
# parent.
self.dependencies = defaultdict(set) # {model: {models}}
def add(self, objs, source=None, nullable=False, reverse_dependency=False):
"""
Add 'objs' to the collection of objects to be deleted. If the call is
the result of a cascade, 'source' should be the model that caused it,
and 'nullable' should be set to True if the relation can be null.
Return a list of all objects that were not already collected.
"""
if not objs:
return []
new_objs = []
model = objs[0].__class__
instances = self.data[model]
for obj in objs:
if obj not in instances:
new_objs.append(obj)
instances.update(new_objs)
# Nullable relationships can be ignored -- they are nulled out before
# deleting, and therefore do not affect the order in which objects have
# to be deleted.
if source is not None and not nullable:
self.add_dependency(source, model, reverse_dependency=reverse_dependency)
return new_objs
def add_dependency(self, model, dependency, reverse_dependency=False):
if reverse_dependency:
model, dependency = dependency, model
self.dependencies[model._meta.concrete_model].add(dependency._meta.concrete_model)
self.data.setdefault(dependency, self.data.default_factory())
def add_field_update(self, field, value, objs):
"""
Schedule a field update. 'objs' must be a homogeneous iterable
collection of model instances (e.g. a QuerySet).
"""
if not objs:
return
model = objs[0].__class__
self.field_updates[model][field, value].update(objs)
def add_restricted_objects(self, field, objs):
if objs:
model = objs[0].__class__
self.restricted_objects[model][field].update(objs)
def clear_restricted_objects_from_set(self, model, objs):
if model in self.restricted_objects:
self.restricted_objects[model] = {
field: items - objs
for field, items in self.restricted_objects[model].items()
}
def clear_restricted_objects_from_queryset(self, model, qs):
if model in self.restricted_objects:
objs = set(qs.filter(pk__in=[
obj.pk
for objs in self.restricted_objects[model].values() for obj in objs
]))
self.clear_restricted_objects_from_set(model, objs)
def _has_signal_listeners(self, model):
return (
signals.pre_delete.has_listeners(model) or
signals.post_delete.has_listeners(model)
)
def can_fast_delete(self, objs, from_field=None):
"""
Determine if the objects in the given queryset-like or single object
can be fast-deleted. This can be done if there are no cascades, no
parents and no signal listeners for the object class.
The 'from_field' tells where we are coming from - we need this to
determine if the objects are in fact to be deleted. Allow also
skipping parent -> child -> parent chain preventing fast delete of
the child.
"""
if from_field and from_field.remote_field.on_delete is not CASCADE:
return False
if hasattr(objs, '_meta'):
model = objs._meta.model
elif hasattr(objs, 'model') and hasattr(objs, '_raw_delete'):
model = objs.model
else:
return False
if self._has_signal_listeners(model):
return False
# The use of from_field comes from the need to avoid cascade back to
# parent when parent delete is cascading to child.
opts = model._meta
return (
all(link == from_field for link in opts.concrete_model._meta.parents.values()) and
# Foreign keys pointing to this model.
all(
related.field.remote_field.on_delete is DO_NOTHING
for related in get_candidate_relations_to_delete(opts)
) and (
# Something like generic foreign key.
not any(hasattr(field, 'bulk_related_objects') for field in opts.private_fields)
)
)
def get_del_batches(self, objs, fields):
"""
Return the objs in suitably sized batches for the used connection.
"""
field_names = [field.name for field in fields]
conn_batch_size = max(
connections[self.using].ops.bulk_batch_size(field_names, objs), 1)
if len(objs) > conn_batch_size:
return [objs[i:i + conn_batch_size]
for i in range(0, len(objs), conn_batch_size)]
else:
return [objs]
def collect(self, objs, source=None, nullable=False, collect_related=True,
source_attr=None, reverse_dependency=False, keep_parents=False,
fail_on_restricted=True):
"""
Add 'objs' to the collection of objects to be deleted as well as all
parent instances. 'objs' must be a homogeneous iterable collection of
model instances (e.g. a QuerySet). If 'collect_related' is True,
related objects will be handled by their respective on_delete handler.
If the call is the result of a cascade, 'source' should be the model
that caused it and 'nullable' should be set to True, if the relation
can be null.
If 'reverse_dependency' is True, 'source' will be deleted before the
current model, rather than after. (Needed for cascading to parent
models, the one case in which the cascade follows the forwards
direction of an FK rather than the reverse direction.)
If 'keep_parents' is True, data of parent model's will be not deleted.
If 'fail_on_restricted' is False, error won't be raised even if it's
prohibited to delete such objects due to RESTRICT, that defers
restricted object checking in recursive calls where the top-level call
may need to collect more objects to determine whether restricted ones
can be deleted.
"""
if self.can_fast_delete(objs):
self.fast_deletes.append(objs)
return
new_objs = self.add(objs, source, nullable,
reverse_dependency=reverse_dependency)
if not new_objs:
return
model = new_objs[0].__class__
if not keep_parents:
# Recursively collect concrete model's parent models, but not their
# related objects. These will be found by meta.get_fields()
concrete_model = model._meta.concrete_model
for ptr in concrete_model._meta.parents.values():
if ptr:
parent_objs = [getattr(obj, ptr.name) for obj in new_objs]
self.collect(parent_objs, source=model,
source_attr=ptr.remote_field.related_name,
collect_related=False,
reverse_dependency=True,
fail_on_restricted=False)
if not collect_related:
return
if keep_parents:
parents = set(model._meta.get_parent_list())
model_fast_deletes = defaultdict(list)
protected_objects = defaultdict(list)
for related in get_candidate_relations_to_delete(model._meta):
# Preserve parent reverse relationships if keep_parents=True.
if keep_parents and related.model in parents:
continue
field = related.field
if field.remote_field.on_delete == DO_NOTHING:
continue
related_model = related.related_model
if self.can_fast_delete(related_model, from_field=field):
model_fast_deletes[related_model].append(field)
continue
batches = self.get_del_batches(new_objs, [field])
for batch in batches:
sub_objs = self.related_objects(related_model, [field], batch)
# Non-referenced fields can be deferred if no signal receivers
# are connected for the related model as they'll never be
# exposed to the user. Skip field deferring when some
# relationships are select_related as interactions between both
# features are hard to get right. This should only happen in
# the rare cases where .related_objects is overridden anyway.
if not (sub_objs.query.select_related or self._has_signal_listeners(related_model)):
referenced_fields = set(chain.from_iterable(
(rf.attname for rf in rel.field.foreign_related_fields)
for rel in get_candidate_relations_to_delete(related_model._meta)
))
sub_objs = sub_objs.only(*tuple(referenced_fields))
if sub_objs:
try:
field.remote_field.on_delete(self, field, sub_objs, self.using)
except ProtectedError as error:
key = "'%s.%s'" % (field.model.__name__, field.name)
protected_objects[key] += error.protected_objects
if protected_objects:
raise ProtectedError(
'Cannot delete some instances of model %r because they are '
'referenced through protected foreign keys: %s.' % (
model.__name__,
', '.join(protected_objects),
),
chain.from_iterable(protected_objects.values()),
)
for related_model, related_fields in model_fast_deletes.items():
batches = self.get_del_batches(new_objs, related_fields)
for batch in batches:
sub_objs = self.related_objects(related_model, related_fields, batch)
self.fast_deletes.append(sub_objs)
for field in model._meta.private_fields:
if hasattr(field, 'bulk_related_objects'):
# It's something like generic foreign key.
sub_objs = field.bulk_related_objects(new_objs, self.using)
self.collect(sub_objs, source=model, nullable=True, fail_on_restricted=False)
if fail_on_restricted:
# Raise an error if collected restricted objects (RESTRICT) aren't
# candidates for deletion also collected via CASCADE.
for related_model, instances in self.data.items():
self.clear_restricted_objects_from_set(related_model, instances)
for qs in self.fast_deletes:
self.clear_restricted_objects_from_queryset(qs.model, qs)
if self.restricted_objects.values():
restricted_objects = defaultdict(list)
for related_model, fields in self.restricted_objects.items():
for field, objs in fields.items():
if objs:
key = "'%s.%s'" % (related_model.__name__, field.name)
restricted_objects[key] += objs
if restricted_objects:
raise RestrictedError(
'Cannot delete some instances of model %r because '
'they are referenced through restricted foreign keys: '
'%s.' % (
model.__name__,
', '.join(restricted_objects),
),
chain.from_iterable(restricted_objects.values()),
)
def related_objects(self, related_model, related_fields, objs):
"""
Get a QuerySet of the related model to objs via related fields.
"""
predicate = reduce(operator.or_, (
query_utils.Q(**{'%s__in' % related_field.name: objs})
for related_field in related_fields
))
return related_model._base_manager.using(self.using).filter(predicate)
def instances_with_model(self):
for model, instances in self.data.items():
for obj in instances:
yield model, obj
def sort(self):
sorted_models = []
concrete_models = set()
models = list(self.data)
while len(sorted_models) < len(models):
found = False
for model in models:
if model in sorted_models:
continue
dependencies = self.dependencies.get(model._meta.concrete_model)
if not (dependencies and dependencies.difference(concrete_models)):
sorted_models.append(model)
concrete_models.add(model._meta.concrete_model)
found = True
if not found:
return
self.data = {model: self.data[model] for model in sorted_models}
def delete(self):
# sort instance collections
for model, instances in self.data.items():
self.data[model] = sorted(instances, key=attrgetter("pk"))
# if possible, bring the models in an order suitable for databases that
# don't support transactions or cannot defer constraint checks until the
# end of a transaction.
self.sort()
# number of objects deleted for each model label
deleted_counter = Counter()
# Optimize for the case with a single obj and no dependencies
if len(self.data) == 1 and len(instances) == 1:
instance = list(instances)[0]
if self.can_fast_delete(instance):
with transaction.mark_for_rollback_on_error():
count = sql.DeleteQuery(model).delete_batch([instance.pk], self.using)
setattr(instance, model._meta.pk.attname, None)
return count, {model._meta.label: count}
with transaction.atomic(using=self.using, savepoint=False):
# send pre_delete signals
for model, obj in self.instances_with_model():
if not model._meta.auto_created:
signals.pre_delete.send(
sender=model, instance=obj, using=self.using
)
# fast deletes
for qs in self.fast_deletes:
count = qs._raw_delete(using=self.using)
if count:
deleted_counter[qs.model._meta.label] += count
# update fields
for model, instances_for_fieldvalues in self.field_updates.items():
for (field, value), instances in instances_for_fieldvalues.items():
query = sql.UpdateQuery(model)
query.update_batch([obj.pk for obj in instances],
{field.name: value}, self.using)
# reverse instance collections
for instances in self.data.values():
instances.reverse()
# delete instances
for model, instances in self.data.items():
query = sql.DeleteQuery(model)
pk_list = [obj.pk for obj in instances]
count = query.delete_batch(pk_list, self.using)
if count:
deleted_counter[model._meta.label] += count
if not model._meta.auto_created:
for obj in instances:
signals.post_delete.send(
sender=model, instance=obj, using=self.using
)
# update collected instances
for instances_for_fieldvalues in self.field_updates.values():
for (field, value), instances in instances_for_fieldvalues.items():
for obj in instances:
setattr(obj, field.attname, value)
for model, instances in self.data.items():
for instance in instances:
setattr(instance, model._meta.pk.attname, None)
return sum(deleted_counter.values()), dict(deleted_counter)
|
5ed6efc638005d286bd4f1d464c5a15aad7441c7fd7df54a8379726863c585a3 | import itertools
import math
import warnings
from copy import copy
from django.core.exceptions import EmptyResultSet
from django.db.models.expressions import Case, Exists, Func, Value, When
from django.db.models.fields import (
BooleanField, CharField, DateTimeField, Field, IntegerField, UUIDField,
)
from django.db.models.query_utils import RegisterLookupMixin
from django.utils.datastructures import OrderedSet
from django.utils.deprecation import RemovedInDjango40Warning
from django.utils.functional import cached_property
class Lookup:
lookup_name = None
prepare_rhs = True
can_use_none_as_rhs = False
def __init__(self, lhs, rhs):
self.lhs, self.rhs = lhs, rhs
self.rhs = self.get_prep_lookup()
if hasattr(self.lhs, 'get_bilateral_transforms'):
bilateral_transforms = self.lhs.get_bilateral_transforms()
else:
bilateral_transforms = []
if bilateral_transforms:
# Warn the user as soon as possible if they are trying to apply
# a bilateral transformation on a nested QuerySet: that won't work.
from django.db.models.sql.query import Query # avoid circular import
if isinstance(rhs, Query):
raise NotImplementedError("Bilateral transformations on nested querysets are not implemented.")
self.bilateral_transforms = bilateral_transforms
def apply_bilateral_transforms(self, value):
for transform in self.bilateral_transforms:
value = transform(value)
return value
def batch_process_rhs(self, compiler, connection, rhs=None):
if rhs is None:
rhs = self.rhs
if self.bilateral_transforms:
sqls, sqls_params = [], []
for p in rhs:
value = Value(p, output_field=self.lhs.output_field)
value = self.apply_bilateral_transforms(value)
value = value.resolve_expression(compiler.query)
sql, sql_params = compiler.compile(value)
sqls.append(sql)
sqls_params.extend(sql_params)
else:
_, params = self.get_db_prep_lookup(rhs, connection)
sqls, sqls_params = ['%s'] * len(params), params
return sqls, sqls_params
def get_source_expressions(self):
if self.rhs_is_direct_value():
return [self.lhs]
return [self.lhs, self.rhs]
def set_source_expressions(self, new_exprs):
if len(new_exprs) == 1:
self.lhs = new_exprs[0]
else:
self.lhs, self.rhs = new_exprs
def get_prep_lookup(self):
if hasattr(self.rhs, 'resolve_expression'):
return self.rhs
if self.prepare_rhs and hasattr(self.lhs.output_field, 'get_prep_value'):
return self.lhs.output_field.get_prep_value(self.rhs)
return self.rhs
def get_db_prep_lookup(self, value, connection):
return ('%s', [value])
def process_lhs(self, compiler, connection, lhs=None):
lhs = lhs or self.lhs
if hasattr(lhs, 'resolve_expression'):
lhs = lhs.resolve_expression(compiler.query)
return compiler.compile(lhs)
def process_rhs(self, compiler, connection):
value = self.rhs
if self.bilateral_transforms:
if self.rhs_is_direct_value():
# Do not call get_db_prep_lookup here as the value will be
# transformed before being used for lookup
value = Value(value, output_field=self.lhs.output_field)
value = self.apply_bilateral_transforms(value)
value = value.resolve_expression(compiler.query)
if hasattr(value, 'as_sql'):
return compiler.compile(value)
else:
return self.get_db_prep_lookup(value, connection)
def rhs_is_direct_value(self):
return not hasattr(self.rhs, 'as_sql')
def relabeled_clone(self, relabels):
new = copy(self)
new.lhs = new.lhs.relabeled_clone(relabels)
if hasattr(new.rhs, 'relabeled_clone'):
new.rhs = new.rhs.relabeled_clone(relabels)
return new
def get_group_by_cols(self, alias=None):
cols = self.lhs.get_group_by_cols()
if hasattr(self.rhs, 'get_group_by_cols'):
cols.extend(self.rhs.get_group_by_cols())
return cols
def as_sql(self, compiler, connection):
raise NotImplementedError
def as_oracle(self, compiler, connection):
# Oracle doesn't allow EXISTS() to be compared to another expression
# unless it's wrapped in a CASE WHEN.
wrapped = False
exprs = []
for expr in (self.lhs, self.rhs):
if isinstance(expr, Exists):
expr = Case(When(expr, then=True), default=False, output_field=BooleanField())
wrapped = True
exprs.append(expr)
lookup = type(self)(*exprs) if wrapped else self
return lookup.as_sql(compiler, connection)
@cached_property
def contains_aggregate(self):
return self.lhs.contains_aggregate or getattr(self.rhs, 'contains_aggregate', False)
@cached_property
def contains_over_clause(self):
return self.lhs.contains_over_clause or getattr(self.rhs, 'contains_over_clause', False)
@property
def is_summary(self):
return self.lhs.is_summary or getattr(self.rhs, 'is_summary', False)
class Transform(RegisterLookupMixin, Func):
"""
RegisterLookupMixin() is first so that get_lookup() and get_transform()
first examine self and then check output_field.
"""
bilateral = False
arity = 1
@property
def lhs(self):
return self.get_source_expressions()[0]
def get_bilateral_transforms(self):
if hasattr(self.lhs, 'get_bilateral_transforms'):
bilateral_transforms = self.lhs.get_bilateral_transforms()
else:
bilateral_transforms = []
if self.bilateral:
bilateral_transforms.append(self.__class__)
return bilateral_transforms
class BuiltinLookup(Lookup):
def process_lhs(self, compiler, connection, lhs=None):
lhs_sql, params = super().process_lhs(compiler, connection, lhs)
field_internal_type = self.lhs.output_field.get_internal_type()
db_type = self.lhs.output_field.db_type(connection=connection)
lhs_sql = connection.ops.field_cast_sql(
db_type, field_internal_type) % lhs_sql
lhs_sql = connection.ops.lookup_cast(self.lookup_name, field_internal_type) % lhs_sql
return lhs_sql, list(params)
def as_sql(self, compiler, connection):
lhs_sql, params = self.process_lhs(compiler, connection)
rhs_sql, rhs_params = self.process_rhs(compiler, connection)
params.extend(rhs_params)
rhs_sql = self.get_rhs_op(connection, rhs_sql)
return '%s %s' % (lhs_sql, rhs_sql), params
def get_rhs_op(self, connection, rhs):
return connection.operators[self.lookup_name] % rhs
class FieldGetDbPrepValueMixin:
"""
Some lookups require Field.get_db_prep_value() to be called on their
inputs.
"""
get_db_prep_lookup_value_is_iterable = False
def get_db_prep_lookup(self, value, connection):
# For relational fields, use the 'target_field' attribute of the
# output_field.
field = getattr(self.lhs.output_field, 'target_field', None)
get_db_prep_value = getattr(field, 'get_db_prep_value', None) or self.lhs.output_field.get_db_prep_value
return (
'%s',
[get_db_prep_value(v, connection, prepared=True) for v in value]
if self.get_db_prep_lookup_value_is_iterable else
[get_db_prep_value(value, connection, prepared=True)]
)
class FieldGetDbPrepValueIterableMixin(FieldGetDbPrepValueMixin):
"""
Some lookups require Field.get_db_prep_value() to be called on each value
in an iterable.
"""
get_db_prep_lookup_value_is_iterable = True
def get_prep_lookup(self):
if hasattr(self.rhs, 'resolve_expression'):
return self.rhs
prepared_values = []
for rhs_value in self.rhs:
if hasattr(rhs_value, 'resolve_expression'):
# An expression will be handled by the database but can coexist
# alongside real values.
pass
elif self.prepare_rhs and hasattr(self.lhs.output_field, 'get_prep_value'):
rhs_value = self.lhs.output_field.get_prep_value(rhs_value)
prepared_values.append(rhs_value)
return prepared_values
def process_rhs(self, compiler, connection):
if self.rhs_is_direct_value():
# rhs should be an iterable of values. Use batch_process_rhs()
# to prepare/transform those values.
return self.batch_process_rhs(compiler, connection)
else:
return super().process_rhs(compiler, connection)
def resolve_expression_parameter(self, compiler, connection, sql, param):
params = [param]
if hasattr(param, 'resolve_expression'):
param = param.resolve_expression(compiler.query)
if hasattr(param, 'as_sql'):
sql, params = param.as_sql(compiler, connection)
return sql, params
def batch_process_rhs(self, compiler, connection, rhs=None):
pre_processed = super().batch_process_rhs(compiler, connection, rhs)
# The params list may contain expressions which compile to a
# sql/param pair. Zip them to get sql and param pairs that refer to the
# same argument and attempt to replace them with the result of
# compiling the param step.
sql, params = zip(*(
self.resolve_expression_parameter(compiler, connection, sql, param)
for sql, param in zip(*pre_processed)
))
params = itertools.chain.from_iterable(params)
return sql, tuple(params)
class PostgresOperatorLookup(FieldGetDbPrepValueMixin, Lookup):
"""Lookup defined by operators on PostgreSQL."""
postgres_operator = None
def as_postgresql(self, compiler, connection):
lhs, lhs_params = self.process_lhs(compiler, connection)
rhs, rhs_params = self.process_rhs(compiler, connection)
params = tuple(lhs_params) + tuple(rhs_params)
return '%s %s %s' % (lhs, self.postgres_operator, rhs), params
@Field.register_lookup
class Exact(FieldGetDbPrepValueMixin, BuiltinLookup):
lookup_name = 'exact'
def process_rhs(self, compiler, connection):
from django.db.models.sql.query import Query
if isinstance(self.rhs, Query):
if self.rhs.has_limit_one():
if not self.rhs.has_select_fields:
self.rhs.clear_select_clause()
self.rhs.add_fields(['pk'])
else:
raise ValueError(
'The QuerySet value for an exact lookup must be limited to '
'one result using slicing.'
)
return super().process_rhs(compiler, connection)
def as_sql(self, compiler, connection):
# Avoid comparison against direct rhs if lhs is a boolean value. That
# turns "boolfield__exact=True" into "WHERE boolean_field" instead of
# "WHERE boolean_field = True" when allowed.
if (
isinstance(self.rhs, bool) and
getattr(self.lhs, 'conditional', False) and
connection.ops.conditional_expression_supported_in_where_clause(self.lhs)
):
lhs_sql, params = self.process_lhs(compiler, connection)
template = '%s' if self.rhs else 'NOT %s'
return template % lhs_sql, params
return super().as_sql(compiler, connection)
@Field.register_lookup
class IExact(BuiltinLookup):
lookup_name = 'iexact'
prepare_rhs = False
def process_rhs(self, qn, connection):
rhs, params = super().process_rhs(qn, connection)
if params:
params[0] = connection.ops.prep_for_iexact_query(params[0])
return rhs, params
@Field.register_lookup
class GreaterThan(FieldGetDbPrepValueMixin, BuiltinLookup):
lookup_name = 'gt'
@Field.register_lookup
class GreaterThanOrEqual(FieldGetDbPrepValueMixin, BuiltinLookup):
lookup_name = 'gte'
@Field.register_lookup
class LessThan(FieldGetDbPrepValueMixin, BuiltinLookup):
lookup_name = 'lt'
@Field.register_lookup
class LessThanOrEqual(FieldGetDbPrepValueMixin, BuiltinLookup):
lookup_name = 'lte'
class IntegerFieldFloatRounding:
"""
Allow floats to work as query values for IntegerField. Without this, the
decimal portion of the float would always be discarded.
"""
def get_prep_lookup(self):
if isinstance(self.rhs, float):
self.rhs = math.ceil(self.rhs)
return super().get_prep_lookup()
@IntegerField.register_lookup
class IntegerGreaterThanOrEqual(IntegerFieldFloatRounding, GreaterThanOrEqual):
pass
@IntegerField.register_lookup
class IntegerLessThan(IntegerFieldFloatRounding, LessThan):
pass
@Field.register_lookup
class In(FieldGetDbPrepValueIterableMixin, BuiltinLookup):
lookup_name = 'in'
def process_rhs(self, compiler, connection):
db_rhs = getattr(self.rhs, '_db', None)
if db_rhs is not None and db_rhs != connection.alias:
raise ValueError(
"Subqueries aren't allowed across different databases. Force "
"the inner query to be evaluated using `list(inner_query)`."
)
if self.rhs_is_direct_value():
try:
rhs = OrderedSet(self.rhs)
except TypeError: # Unhashable items in self.rhs
rhs = self.rhs
if not rhs:
raise EmptyResultSet
# rhs should be an iterable; use batch_process_rhs() to
# prepare/transform those values.
sqls, sqls_params = self.batch_process_rhs(compiler, connection, rhs)
placeholder = '(' + ', '.join(sqls) + ')'
return (placeholder, sqls_params)
else:
if not getattr(self.rhs, 'has_select_fields', True):
self.rhs.clear_select_clause()
self.rhs.add_fields(['pk'])
return super().process_rhs(compiler, connection)
def get_rhs_op(self, connection, rhs):
return 'IN %s' % rhs
def as_sql(self, compiler, connection):
max_in_list_size = connection.ops.max_in_list_size()
if self.rhs_is_direct_value() and max_in_list_size and len(self.rhs) > max_in_list_size:
return self.split_parameter_list_as_sql(compiler, connection)
return super().as_sql(compiler, connection)
def split_parameter_list_as_sql(self, compiler, connection):
# This is a special case for databases which limit the number of
# elements which can appear in an 'IN' clause.
max_in_list_size = connection.ops.max_in_list_size()
lhs, lhs_params = self.process_lhs(compiler, connection)
rhs, rhs_params = self.batch_process_rhs(compiler, connection)
in_clause_elements = ['(']
params = []
for offset in range(0, len(rhs_params), max_in_list_size):
if offset > 0:
in_clause_elements.append(' OR ')
in_clause_elements.append('%s IN (' % lhs)
params.extend(lhs_params)
sqls = rhs[offset: offset + max_in_list_size]
sqls_params = rhs_params[offset: offset + max_in_list_size]
param_group = ', '.join(sqls)
in_clause_elements.append(param_group)
in_clause_elements.append(')')
params.extend(sqls_params)
in_clause_elements.append(')')
return ''.join(in_clause_elements), params
class PatternLookup(BuiltinLookup):
param_pattern = '%%%s%%'
prepare_rhs = False
def get_rhs_op(self, connection, rhs):
# Assume we are in startswith. We need to produce SQL like:
# col LIKE %s, ['thevalue%']
# For python values we can (and should) do that directly in Python,
# but if the value is for example reference to other column, then
# we need to add the % pattern match to the lookup by something like
# col LIKE othercol || '%%'
# So, for Python values we don't need any special pattern, but for
# SQL reference values or SQL transformations we need the correct
# pattern added.
if hasattr(self.rhs, 'as_sql') or self.bilateral_transforms:
pattern = connection.pattern_ops[self.lookup_name].format(connection.pattern_esc)
return pattern.format(rhs)
else:
return super().get_rhs_op(connection, rhs)
def process_rhs(self, qn, connection):
rhs, params = super().process_rhs(qn, connection)
if self.rhs_is_direct_value() and params and not self.bilateral_transforms:
params[0] = self.param_pattern % connection.ops.prep_for_like_query(params[0])
return rhs, params
@Field.register_lookup
class Contains(PatternLookup):
lookup_name = 'contains'
@Field.register_lookup
class IContains(Contains):
lookup_name = 'icontains'
@Field.register_lookup
class StartsWith(PatternLookup):
lookup_name = 'startswith'
param_pattern = '%s%%'
@Field.register_lookup
class IStartsWith(StartsWith):
lookup_name = 'istartswith'
@Field.register_lookup
class EndsWith(PatternLookup):
lookup_name = 'endswith'
param_pattern = '%%%s'
@Field.register_lookup
class IEndsWith(EndsWith):
lookup_name = 'iendswith'
@Field.register_lookup
class Range(FieldGetDbPrepValueIterableMixin, BuiltinLookup):
lookup_name = 'range'
def get_rhs_op(self, connection, rhs):
return "BETWEEN %s AND %s" % (rhs[0], rhs[1])
@Field.register_lookup
class IsNull(BuiltinLookup):
lookup_name = 'isnull'
prepare_rhs = False
def as_sql(self, compiler, connection):
if not isinstance(self.rhs, bool):
# When the deprecation ends, replace with:
# raise ValueError(
# 'The QuerySet value for an isnull lookup must be True or '
# 'False.'
# )
warnings.warn(
'Using a non-boolean value for an isnull lookup is '
'deprecated, use True or False instead.',
RemovedInDjango40Warning,
)
sql, params = compiler.compile(self.lhs)
if self.rhs:
return "%s IS NULL" % sql, params
else:
return "%s IS NOT NULL" % sql, params
@Field.register_lookup
class Regex(BuiltinLookup):
lookup_name = 'regex'
prepare_rhs = False
def as_sql(self, compiler, connection):
if self.lookup_name in connection.operators:
return super().as_sql(compiler, connection)
else:
lhs, lhs_params = self.process_lhs(compiler, connection)
rhs, rhs_params = self.process_rhs(compiler, connection)
sql_template = connection.ops.regex_lookup(self.lookup_name)
return sql_template % (lhs, rhs), lhs_params + rhs_params
@Field.register_lookup
class IRegex(Regex):
lookup_name = 'iregex'
class YearLookup(Lookup):
def year_lookup_bounds(self, connection, year):
output_field = self.lhs.lhs.output_field
if isinstance(output_field, DateTimeField):
bounds = connection.ops.year_lookup_bounds_for_datetime_field(year)
else:
bounds = connection.ops.year_lookup_bounds_for_date_field(year)
return bounds
def as_sql(self, compiler, connection):
# Avoid the extract operation if the rhs is a direct value to allow
# indexes to be used.
if self.rhs_is_direct_value():
# Skip the extract part by directly using the originating field,
# that is self.lhs.lhs.
lhs_sql, params = self.process_lhs(compiler, connection, self.lhs.lhs)
rhs_sql, _ = self.process_rhs(compiler, connection)
rhs_sql = self.get_direct_rhs_sql(connection, rhs_sql)
start, finish = self.year_lookup_bounds(connection, self.rhs)
params.extend(self.get_bound_params(start, finish))
return '%s %s' % (lhs_sql, rhs_sql), params
return super().as_sql(compiler, connection)
def get_direct_rhs_sql(self, connection, rhs):
return connection.operators[self.lookup_name] % rhs
def get_bound_params(self, start, finish):
raise NotImplementedError(
'subclasses of YearLookup must provide a get_bound_params() method'
)
class YearExact(YearLookup, Exact):
def get_direct_rhs_sql(self, connection, rhs):
return 'BETWEEN %s AND %s'
def get_bound_params(self, start, finish):
return (start, finish)
class YearGt(YearLookup, GreaterThan):
def get_bound_params(self, start, finish):
return (finish,)
class YearGte(YearLookup, GreaterThanOrEqual):
def get_bound_params(self, start, finish):
return (start,)
class YearLt(YearLookup, LessThan):
def get_bound_params(self, start, finish):
return (start,)
class YearLte(YearLookup, LessThanOrEqual):
def get_bound_params(self, start, finish):
return (finish,)
class UUIDTextMixin:
"""
Strip hyphens from a value when filtering a UUIDField on backends without
a native datatype for UUID.
"""
def process_rhs(self, qn, connection):
if not connection.features.has_native_uuid_field:
from django.db.models.functions import Replace
if self.rhs_is_direct_value():
self.rhs = Value(self.rhs)
self.rhs = Replace(self.rhs, Value('-'), Value(''), output_field=CharField())
rhs, params = super().process_rhs(qn, connection)
return rhs, params
@UUIDField.register_lookup
class UUIDIExact(UUIDTextMixin, IExact):
pass
@UUIDField.register_lookup
class UUIDContains(UUIDTextMixin, Contains):
pass
@UUIDField.register_lookup
class UUIDIContains(UUIDTextMixin, IContains):
pass
@UUIDField.register_lookup
class UUIDStartsWith(UUIDTextMixin, StartsWith):
pass
@UUIDField.register_lookup
class UUIDIStartsWith(UUIDTextMixin, IStartsWith):
pass
@UUIDField.register_lookup
class UUIDEndsWith(UUIDTextMixin, EndsWith):
pass
@UUIDField.register_lookup
class UUIDIEndsWith(UUIDTextMixin, IEndsWith):
pass
|
c29abd3e6da3fe31239764422b23d6c8af272f24507ce88a92139c9a3995987e | from enum import Enum
from django.db.models.query_utils import Q
from django.db.models.sql.query import Query
__all__ = ['CheckConstraint', 'Deferrable', 'UniqueConstraint']
class BaseConstraint:
def __init__(self, name):
self.name = name
def constraint_sql(self, model, schema_editor):
raise NotImplementedError('This method must be implemented by a subclass.')
def create_sql(self, model, schema_editor):
raise NotImplementedError('This method must be implemented by a subclass.')
def remove_sql(self, model, schema_editor):
raise NotImplementedError('This method must be implemented by a subclass.')
def deconstruct(self):
path = '%s.%s' % (self.__class__.__module__, self.__class__.__name__)
path = path.replace('django.db.models.constraints', 'django.db.models')
return (path, (), {'name': self.name})
def clone(self):
_, args, kwargs = self.deconstruct()
return self.__class__(*args, **kwargs)
class CheckConstraint(BaseConstraint):
def __init__(self, *, check, name):
self.check = check
if not getattr(check, 'conditional', False):
raise TypeError(
'CheckConstraint.check must be a Q instance or boolean '
'expression.'
)
super().__init__(name)
def _get_check_sql(self, model, schema_editor):
query = Query(model=model, alias_cols=False)
where = query.build_where(self.check)
compiler = query.get_compiler(connection=schema_editor.connection)
sql, params = where.as_sql(compiler, schema_editor.connection)
return sql % tuple(schema_editor.quote_value(p) for p in params)
def constraint_sql(self, model, schema_editor):
check = self._get_check_sql(model, schema_editor)
return schema_editor._check_sql(self.name, check)
def create_sql(self, model, schema_editor):
check = self._get_check_sql(model, schema_editor)
return schema_editor._create_check_sql(model, self.name, check)
def remove_sql(self, model, schema_editor):
return schema_editor._delete_check_sql(model, self.name)
def __repr__(self):
return "<%s: check='%s' name=%r>" % (self.__class__.__name__, self.check, self.name)
def __eq__(self, other):
if isinstance(other, CheckConstraint):
return self.name == other.name and self.check == other.check
return super().__eq__(other)
def deconstruct(self):
path, args, kwargs = super().deconstruct()
kwargs['check'] = self.check
return path, args, kwargs
class Deferrable(Enum):
DEFERRED = 'deferred'
IMMEDIATE = 'immediate'
class UniqueConstraint(BaseConstraint):
def __init__(self, *, fields, name, condition=None, deferrable=None):
if not fields:
raise ValueError('At least one field is required to define a unique constraint.')
if not isinstance(condition, (type(None), Q)):
raise ValueError('UniqueConstraint.condition must be a Q instance.')
if condition and deferrable:
raise ValueError(
'UniqueConstraint with conditions cannot be deferred.'
)
if not isinstance(deferrable, (type(None), Deferrable)):
raise ValueError(
'UniqueConstraint.deferrable must be a Deferrable instance.'
)
self.fields = tuple(fields)
self.condition = condition
self.deferrable = deferrable
super().__init__(name)
def _get_condition_sql(self, model, schema_editor):
if self.condition is None:
return None
query = Query(model=model, alias_cols=False)
where = query.build_where(self.condition)
compiler = query.get_compiler(connection=schema_editor.connection)
sql, params = where.as_sql(compiler, schema_editor.connection)
return sql % tuple(schema_editor.quote_value(p) for p in params)
def constraint_sql(self, model, schema_editor):
fields = [model._meta.get_field(field_name).column for field_name in self.fields]
condition = self._get_condition_sql(model, schema_editor)
return schema_editor._unique_sql(
model, fields, self.name, condition=condition,
deferrable=self.deferrable,
)
def create_sql(self, model, schema_editor):
fields = [model._meta.get_field(field_name).column for field_name in self.fields]
condition = self._get_condition_sql(model, schema_editor)
return schema_editor._create_unique_sql(
model, fields, self.name, condition=condition,
deferrable=self.deferrable,
)
def remove_sql(self, model, schema_editor):
condition = self._get_condition_sql(model, schema_editor)
return schema_editor._delete_unique_sql(
model, self.name, condition=condition, deferrable=self.deferrable,
)
def __repr__(self):
return '<%s: fields=%r name=%r%s%s>' % (
self.__class__.__name__, self.fields, self.name,
'' if self.condition is None else ' condition=%s' % self.condition,
'' if self.deferrable is None else ' deferrable=%s' % self.deferrable,
)
def __eq__(self, other):
if isinstance(other, UniqueConstraint):
return (
self.name == other.name and
self.fields == other.fields and
self.condition == other.condition and
self.deferrable == other.deferrable
)
return super().__eq__(other)
def deconstruct(self):
path, args, kwargs = super().deconstruct()
kwargs['fields'] = self.fields
if self.condition:
kwargs['condition'] = self.condition
if self.deferrable:
kwargs['deferrable'] = self.deferrable
return path, args, kwargs
|
cdeff7f43edc36fe9f5609d581ce460bce4f0eebc6134c5d11796e593b4e94fa | import datetime
import decimal
import functools
import hashlib
import logging
import time
from contextlib import contextmanager
from django.db import NotSupportedError
logger = logging.getLogger('django.db.backends')
class CursorWrapper:
def __init__(self, cursor, db):
self.cursor = cursor
self.db = db
WRAP_ERROR_ATTRS = frozenset(['fetchone', 'fetchmany', 'fetchall', 'nextset'])
def __getattr__(self, attr):
cursor_attr = getattr(self.cursor, attr)
if attr in CursorWrapper.WRAP_ERROR_ATTRS:
return self.db.wrap_database_errors(cursor_attr)
else:
return cursor_attr
def __iter__(self):
with self.db.wrap_database_errors:
yield from self.cursor
def __enter__(self):
return self
def __exit__(self, type, value, traceback):
# Close instead of passing through to avoid backend-specific behavior
# (#17671). Catch errors liberally because errors in cleanup code
# aren't useful.
try:
self.close()
except self.db.Database.Error:
pass
# The following methods cannot be implemented in __getattr__, because the
# code must run when the method is invoked, not just when it is accessed.
def callproc(self, procname, params=None, kparams=None):
# Keyword parameters for callproc aren't supported in PEP 249, but the
# database driver may support them (e.g. cx_Oracle).
if kparams is not None and not self.db.features.supports_callproc_kwargs:
raise NotSupportedError(
'Keyword parameters for callproc are not supported on this '
'database backend.'
)
self.db.validate_no_broken_transaction()
with self.db.wrap_database_errors:
if params is None and kparams is None:
return self.cursor.callproc(procname)
elif kparams is None:
return self.cursor.callproc(procname, params)
else:
params = params or ()
return self.cursor.callproc(procname, params, kparams)
def execute(self, sql, params=None):
return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
def executemany(self, sql, param_list):
return self._execute_with_wrappers(sql, param_list, many=True, executor=self._executemany)
def _execute_with_wrappers(self, sql, params, many, executor):
context = {'connection': self.db, 'cursor': self}
for wrapper in reversed(self.db.execute_wrappers):
executor = functools.partial(wrapper, executor)
return executor(sql, params, many, context)
def _execute(self, sql, params, *ignored_wrapper_args):
self.db.validate_no_broken_transaction()
with self.db.wrap_database_errors:
if params is None:
# params default might be backend specific.
return self.cursor.execute(sql)
else:
return self.cursor.execute(sql, params)
def _executemany(self, sql, param_list, *ignored_wrapper_args):
self.db.validate_no_broken_transaction()
with self.db.wrap_database_errors:
return self.cursor.executemany(sql, param_list)
class CursorDebugWrapper(CursorWrapper):
# XXX callproc isn't instrumented at this time.
def execute(self, sql, params=None):
with self.debug_sql(sql, params, use_last_executed_query=True):
return super().execute(sql, params)
def executemany(self, sql, param_list):
with self.debug_sql(sql, param_list, many=True):
return super().executemany(sql, param_list)
@contextmanager
def debug_sql(self, sql=None, params=None, use_last_executed_query=False, many=False):
start = time.monotonic()
try:
yield
finally:
stop = time.monotonic()
duration = stop - start
if use_last_executed_query:
sql = self.db.ops.last_executed_query(self.cursor, sql, params)
try:
times = len(params) if many else ''
except TypeError:
# params could be an iterator.
times = '?'
self.db.queries_log.append({
'sql': '%s times: %s' % (times, sql) if many else sql,
'time': '%.3f' % duration,
})
logger.debug(
'(%.3f) %s; args=%s',
duration,
sql,
params,
extra={'duration': duration, 'sql': sql, 'params': params},
)
###############################################
# Converters from database (string) to Python #
###############################################
def typecast_date(s):
return datetime.date(*map(int, s.split('-'))) if s else None # return None if s is null
def typecast_time(s): # does NOT store time zone information
if not s:
return None
hour, minutes, seconds = s.split(':')
if '.' in seconds: # check whether seconds have a fractional part
seconds, microseconds = seconds.split('.')
else:
microseconds = '0'
return datetime.time(int(hour), int(minutes), int(seconds), int((microseconds + '000000')[:6]))
def typecast_timestamp(s): # does NOT store time zone information
# "2005-07-29 15:48:00.590358-05"
# "2005-07-29 09:56:00-05"
if not s:
return None
if ' ' not in s:
return typecast_date(s)
d, t = s.split()
# Remove timezone information.
if '-' in t:
t, _ = t.split('-', 1)
elif '+' in t:
t, _ = t.split('+', 1)
dates = d.split('-')
times = t.split(':')
seconds = times[2]
if '.' in seconds: # check whether seconds have a fractional part
seconds, microseconds = seconds.split('.')
else:
microseconds = '0'
return datetime.datetime(
int(dates[0]), int(dates[1]), int(dates[2]),
int(times[0]), int(times[1]), int(seconds),
int((microseconds + '000000')[:6])
)
###############################################
# Converters from Python to database (string) #
###############################################
def split_identifier(identifier):
"""
Split an SQL identifier into a two element tuple of (namespace, name).
The identifier could be a table, column, or sequence name might be prefixed
by a namespace.
"""
try:
namespace, name = identifier.split('"."')
except ValueError:
namespace, name = '', identifier
return namespace.strip('"'), name.strip('"')
def truncate_name(identifier, length=None, hash_len=4):
"""
Shorten an SQL identifier to a repeatable mangled version with the given
length.
If a quote stripped name contains a namespace, e.g. USERNAME"."TABLE,
truncate the table portion only.
"""
namespace, name = split_identifier(identifier)
if length is None or len(name) <= length:
return identifier
digest = names_digest(name, length=hash_len)
return '%s%s%s' % ('%s"."' % namespace if namespace else '', name[:length - hash_len], digest)
def names_digest(*args, length):
"""
Generate a 32-bit digest of a set of arguments that can be used to shorten
identifying names.
"""
h = hashlib.md5()
for arg in args:
h.update(arg.encode())
return h.hexdigest()[:length]
def format_number(value, max_digits, decimal_places):
"""
Format a number into a string with the requisite number of digits and
decimal places.
"""
if value is None:
return None
context = decimal.getcontext().copy()
if max_digits is not None:
context.prec = max_digits
if decimal_places is not None:
value = value.quantize(decimal.Decimal(1).scaleb(-decimal_places), context=context)
else:
context.traps[decimal.Rounded] = 1
value = context.create_decimal(value)
return "{:f}".format(value)
def strip_quotes(table_name):
"""
Strip quotes off of quoted table names to make them safe for use in index
names, sequence names, etc. For example '"USER"."TABLE"' (an Oracle naming
scheme) becomes 'USER"."TABLE'.
"""
has_quotes = table_name.startswith('"') and table_name.endswith('"')
return table_name[1:-1] if has_quotes else table_name
|
625d782a36098a34edd72a48662ae9f74952ed44c9f14a203c523f0f06dcb127 | from django.dispatch import Signal
connection_created = Signal()
|
ae4e8366d59ff252c86ac7e5c8d7c7c1ccbfa7773f99530ac434e1dd6161799a | from django.db import models
from django.db.migrations.operations.base import Operation
from django.db.migrations.state import ModelState
from django.db.models.options import normalize_together
from django.utils.functional import cached_property
from .fields import (
AddField, AlterField, FieldOperation, RemoveField, RenameField,
)
from .utils import field_references, get_references, resolve_relation
def _check_for_duplicates(arg_name, objs):
used_vals = set()
for val in objs:
if val in used_vals:
raise ValueError(
"Found duplicate value %s in CreateModel %s argument." % (val, arg_name)
)
used_vals.add(val)
class ModelOperation(Operation):
def __init__(self, name):
self.name = name
@cached_property
def name_lower(self):
return self.name.lower()
def references_model(self, name, app_label):
return name.lower() == self.name_lower
def reduce(self, operation, app_label):
return (
super().reduce(operation, app_label) or
not operation.references_model(self.name, app_label)
)
class CreateModel(ModelOperation):
"""Create a model's table."""
serialization_expand_args = ['fields', 'options', 'managers']
def __init__(self, name, fields, options=None, bases=None, managers=None):
self.fields = fields
self.options = options or {}
self.bases = bases or (models.Model,)
self.managers = managers or []
super().__init__(name)
# Sanity-check that there are no duplicated field names, bases, or
# manager names
_check_for_duplicates('fields', (name for name, _ in self.fields))
_check_for_duplicates('bases', (
base._meta.label_lower if hasattr(base, '_meta') else
base.lower() if isinstance(base, str) else base
for base in self.bases
))
_check_for_duplicates('managers', (name for name, _ in self.managers))
def deconstruct(self):
kwargs = {
'name': self.name,
'fields': self.fields,
}
if self.options:
kwargs['options'] = self.options
if self.bases and self.bases != (models.Model,):
kwargs['bases'] = self.bases
if self.managers and self.managers != [('objects', models.Manager())]:
kwargs['managers'] = self.managers
return (
self.__class__.__qualname__,
[],
kwargs
)
def state_forwards(self, app_label, state):
state.add_model(ModelState(
app_label,
self.name,
list(self.fields),
dict(self.options),
tuple(self.bases),
list(self.managers),
))
def database_forwards(self, app_label, schema_editor, from_state, to_state):
model = to_state.apps.get_model(app_label, self.name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
schema_editor.create_model(model)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
model = from_state.apps.get_model(app_label, self.name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
schema_editor.delete_model(model)
def describe(self):
return "Create %smodel %s" % ("proxy " if self.options.get("proxy", False) else "", self.name)
def references_model(self, name, app_label):
name_lower = name.lower()
if name_lower == self.name_lower:
return True
# Check we didn't inherit from the model
reference_model_tuple = (app_label, name_lower)
for base in self.bases:
if (base is not models.Model and isinstance(base, (models.base.ModelBase, str)) and
resolve_relation(base, app_label) == reference_model_tuple):
return True
# Check we have no FKs/M2Ms with it
for _name, field in self.fields:
if field_references((app_label, self.name_lower), field, reference_model_tuple):
return True
return False
def reduce(self, operation, app_label):
if (isinstance(operation, DeleteModel) and
self.name_lower == operation.name_lower and
not self.options.get("proxy", False)):
return []
elif isinstance(operation, RenameModel) and self.name_lower == operation.old_name_lower:
return [
CreateModel(
operation.new_name,
fields=self.fields,
options=self.options,
bases=self.bases,
managers=self.managers,
),
]
elif isinstance(operation, AlterModelOptions) and self.name_lower == operation.name_lower:
return [
CreateModel(
self.name,
fields=self.fields,
options={**self.options, **operation.options},
bases=self.bases,
managers=self.managers,
),
]
elif isinstance(operation, AlterTogetherOptionOperation) and self.name_lower == operation.name_lower:
return [
CreateModel(
self.name,
fields=self.fields,
options={**self.options, **{operation.option_name: operation.option_value}},
bases=self.bases,
managers=self.managers,
),
]
elif isinstance(operation, AlterOrderWithRespectTo) and self.name_lower == operation.name_lower:
return [
CreateModel(
self.name,
fields=self.fields,
options={**self.options, 'order_with_respect_to': operation.order_with_respect_to},
bases=self.bases,
managers=self.managers,
),
]
elif isinstance(operation, FieldOperation) and self.name_lower == operation.model_name_lower:
if isinstance(operation, AddField):
return [
CreateModel(
self.name,
fields=self.fields + [(operation.name, operation.field)],
options=self.options,
bases=self.bases,
managers=self.managers,
),
]
elif isinstance(operation, AlterField):
return [
CreateModel(
self.name,
fields=[
(n, operation.field if n == operation.name else v)
for n, v in self.fields
],
options=self.options,
bases=self.bases,
managers=self.managers,
),
]
elif isinstance(operation, RemoveField):
options = self.options.copy()
for option_name in ('unique_together', 'index_together'):
option = options.pop(option_name, None)
if option:
option = set(filter(bool, (
tuple(f for f in fields if f != operation.name_lower) for fields in option
)))
if option:
options[option_name] = option
order_with_respect_to = options.get('order_with_respect_to')
if order_with_respect_to == operation.name_lower:
del options['order_with_respect_to']
return [
CreateModel(
self.name,
fields=[
(n, v)
for n, v in self.fields
if n.lower() != operation.name_lower
],
options=options,
bases=self.bases,
managers=self.managers,
),
]
elif isinstance(operation, RenameField):
options = self.options.copy()
for option_name in ('unique_together', 'index_together'):
option = options.get(option_name)
if option:
options[option_name] = {
tuple(operation.new_name if f == operation.old_name else f for f in fields)
for fields in option
}
order_with_respect_to = options.get('order_with_respect_to')
if order_with_respect_to == operation.old_name:
options['order_with_respect_to'] = operation.new_name
return [
CreateModel(
self.name,
fields=[
(operation.new_name if n == operation.old_name else n, v)
for n, v in self.fields
],
options=options,
bases=self.bases,
managers=self.managers,
),
]
return super().reduce(operation, app_label)
class DeleteModel(ModelOperation):
"""Drop a model's table."""
def deconstruct(self):
kwargs = {
'name': self.name,
}
return (
self.__class__.__qualname__,
[],
kwargs
)
def state_forwards(self, app_label, state):
state.remove_model(app_label, self.name_lower)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
model = from_state.apps.get_model(app_label, self.name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
schema_editor.delete_model(model)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
model = to_state.apps.get_model(app_label, self.name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
schema_editor.create_model(model)
def references_model(self, name, app_label):
# The deleted model could be referencing the specified model through
# related fields.
return True
def describe(self):
return "Delete model %s" % self.name
class RenameModel(ModelOperation):
"""Rename a model."""
def __init__(self, old_name, new_name):
self.old_name = old_name
self.new_name = new_name
super().__init__(old_name)
@cached_property
def old_name_lower(self):
return self.old_name.lower()
@cached_property
def new_name_lower(self):
return self.new_name.lower()
def deconstruct(self):
kwargs = {
'old_name': self.old_name,
'new_name': self.new_name,
}
return (
self.__class__.__qualname__,
[],
kwargs
)
def state_forwards(self, app_label, state):
# Add a new model.
renamed_model = state.models[app_label, self.old_name_lower].clone()
renamed_model.name = self.new_name
state.models[app_label, self.new_name_lower] = renamed_model
# Repoint all fields pointing to the old model to the new one.
old_model_tuple = (app_label, self.old_name_lower)
new_remote_model = '%s.%s' % (app_label, self.new_name)
to_reload = set()
for model_state, name, field, reference in get_references(state, old_model_tuple):
changed_field = None
if reference.to:
changed_field = field.clone()
changed_field.remote_field.model = new_remote_model
if reference.through:
if changed_field is None:
changed_field = field.clone()
changed_field.remote_field.through = new_remote_model
if changed_field:
model_state.fields[name] = changed_field
to_reload.add((model_state.app_label, model_state.name_lower))
# Reload models related to old model before removing the old model.
state.reload_models(to_reload, delay=True)
# Remove the old model.
state.remove_model(app_label, self.old_name_lower)
state.reload_model(app_label, self.new_name_lower, delay=True)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
new_model = to_state.apps.get_model(app_label, self.new_name)
if self.allow_migrate_model(schema_editor.connection.alias, new_model):
old_model = from_state.apps.get_model(app_label, self.old_name)
# Move the main table
schema_editor.alter_db_table(
new_model,
old_model._meta.db_table,
new_model._meta.db_table,
)
# Alter the fields pointing to us
for related_object in old_model._meta.related_objects:
if related_object.related_model == old_model:
model = new_model
related_key = (app_label, self.new_name_lower)
else:
model = related_object.related_model
related_key = (
related_object.related_model._meta.app_label,
related_object.related_model._meta.model_name,
)
to_field = to_state.apps.get_model(
*related_key
)._meta.get_field(related_object.field.name)
schema_editor.alter_field(
model,
related_object.field,
to_field,
)
# Rename M2M fields whose name is based on this model's name.
fields = zip(old_model._meta.local_many_to_many, new_model._meta.local_many_to_many)
for (old_field, new_field) in fields:
# Skip self-referential fields as these are renamed above.
if new_field.model == new_field.related_model or not new_field.remote_field.through._meta.auto_created:
continue
# Rename the M2M table that's based on this model's name.
old_m2m_model = old_field.remote_field.through
new_m2m_model = new_field.remote_field.through
schema_editor.alter_db_table(
new_m2m_model,
old_m2m_model._meta.db_table,
new_m2m_model._meta.db_table,
)
# Rename the column in the M2M table that's based on this
# model's name.
schema_editor.alter_field(
new_m2m_model,
old_m2m_model._meta.get_field(old_model._meta.model_name),
new_m2m_model._meta.get_field(new_model._meta.model_name),
)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
self.new_name_lower, self.old_name_lower = self.old_name_lower, self.new_name_lower
self.new_name, self.old_name = self.old_name, self.new_name
self.database_forwards(app_label, schema_editor, from_state, to_state)
self.new_name_lower, self.old_name_lower = self.old_name_lower, self.new_name_lower
self.new_name, self.old_name = self.old_name, self.new_name
def references_model(self, name, app_label):
return (
name.lower() == self.old_name_lower or
name.lower() == self.new_name_lower
)
def describe(self):
return "Rename model %s to %s" % (self.old_name, self.new_name)
def reduce(self, operation, app_label):
if (isinstance(operation, RenameModel) and
self.new_name_lower == operation.old_name_lower):
return [
RenameModel(
self.old_name,
operation.new_name,
),
]
# Skip `ModelOperation.reduce` as we want to run `references_model`
# against self.new_name.
return (
super(ModelOperation, self).reduce(operation, app_label) or
not operation.references_model(self.new_name, app_label)
)
class ModelOptionOperation(ModelOperation):
def reduce(self, operation, app_label):
if isinstance(operation, (self.__class__, DeleteModel)) and self.name_lower == operation.name_lower:
return [operation]
return super().reduce(operation, app_label)
class AlterModelTable(ModelOptionOperation):
"""Rename a model's table."""
def __init__(self, name, table):
self.table = table
super().__init__(name)
def deconstruct(self):
kwargs = {
'name': self.name,
'table': self.table,
}
return (
self.__class__.__qualname__,
[],
kwargs
)
def state_forwards(self, app_label, state):
state.models[app_label, self.name_lower].options["db_table"] = self.table
state.reload_model(app_label, self.name_lower, delay=True)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
new_model = to_state.apps.get_model(app_label, self.name)
if self.allow_migrate_model(schema_editor.connection.alias, new_model):
old_model = from_state.apps.get_model(app_label, self.name)
schema_editor.alter_db_table(
new_model,
old_model._meta.db_table,
new_model._meta.db_table,
)
# Rename M2M fields whose name is based on this model's db_table
for (old_field, new_field) in zip(old_model._meta.local_many_to_many, new_model._meta.local_many_to_many):
if new_field.remote_field.through._meta.auto_created:
schema_editor.alter_db_table(
new_field.remote_field.through,
old_field.remote_field.through._meta.db_table,
new_field.remote_field.through._meta.db_table,
)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
return self.database_forwards(app_label, schema_editor, from_state, to_state)
def describe(self):
return "Rename table for %s to %s" % (
self.name,
self.table if self.table is not None else "(default)"
)
class AlterTogetherOptionOperation(ModelOptionOperation):
option_name = None
def __init__(self, name, option_value):
if option_value:
option_value = set(normalize_together(option_value))
setattr(self, self.option_name, option_value)
super().__init__(name)
@cached_property
def option_value(self):
return getattr(self, self.option_name)
def deconstruct(self):
kwargs = {
'name': self.name,
self.option_name: self.option_value,
}
return (
self.__class__.__qualname__,
[],
kwargs
)
def state_forwards(self, app_label, state):
model_state = state.models[app_label, self.name_lower]
model_state.options[self.option_name] = self.option_value
state.reload_model(app_label, self.name_lower, delay=True)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
new_model = to_state.apps.get_model(app_label, self.name)
if self.allow_migrate_model(schema_editor.connection.alias, new_model):
old_model = from_state.apps.get_model(app_label, self.name)
alter_together = getattr(schema_editor, 'alter_%s' % self.option_name)
alter_together(
new_model,
getattr(old_model._meta, self.option_name, set()),
getattr(new_model._meta, self.option_name, set()),
)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
return self.database_forwards(app_label, schema_editor, from_state, to_state)
def references_field(self, model_name, name, app_label):
return (
self.references_model(model_name, app_label) and
(
not self.option_value or
any((name in fields) for fields in self.option_value)
)
)
def describe(self):
return "Alter %s for %s (%s constraint(s))" % (self.option_name, self.name, len(self.option_value or ''))
class AlterUniqueTogether(AlterTogetherOptionOperation):
"""
Change the value of unique_together to the target one.
Input value of unique_together must be a set of tuples.
"""
option_name = 'unique_together'
def __init__(self, name, unique_together):
super().__init__(name, unique_together)
class AlterIndexTogether(AlterTogetherOptionOperation):
"""
Change the value of index_together to the target one.
Input value of index_together must be a set of tuples.
"""
option_name = "index_together"
def __init__(self, name, index_together):
super().__init__(name, index_together)
class AlterOrderWithRespectTo(ModelOptionOperation):
"""Represent a change with the order_with_respect_to option."""
option_name = 'order_with_respect_to'
def __init__(self, name, order_with_respect_to):
self.order_with_respect_to = order_with_respect_to
super().__init__(name)
def deconstruct(self):
kwargs = {
'name': self.name,
'order_with_respect_to': self.order_with_respect_to,
}
return (
self.__class__.__qualname__,
[],
kwargs
)
def state_forwards(self, app_label, state):
model_state = state.models[app_label, self.name_lower]
model_state.options['order_with_respect_to'] = self.order_with_respect_to
state.reload_model(app_label, self.name_lower, delay=True)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
to_model = to_state.apps.get_model(app_label, self.name)
if self.allow_migrate_model(schema_editor.connection.alias, to_model):
from_model = from_state.apps.get_model(app_label, self.name)
# Remove a field if we need to
if from_model._meta.order_with_respect_to and not to_model._meta.order_with_respect_to:
schema_editor.remove_field(from_model, from_model._meta.get_field("_order"))
# Add a field if we need to (altering the column is untouched as
# it's likely a rename)
elif to_model._meta.order_with_respect_to and not from_model._meta.order_with_respect_to:
field = to_model._meta.get_field("_order")
if not field.has_default():
field.default = 0
schema_editor.add_field(
from_model,
field,
)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
self.database_forwards(app_label, schema_editor, from_state, to_state)
def references_field(self, model_name, name, app_label):
return (
self.references_model(model_name, app_label) and
(
self.order_with_respect_to is None or
name == self.order_with_respect_to
)
)
def describe(self):
return "Set order_with_respect_to on %s to %s" % (self.name, self.order_with_respect_to)
class AlterModelOptions(ModelOptionOperation):
"""
Set new model options that don't directly affect the database schema
(like verbose_name, permissions, ordering). Python code in migrations
may still need them.
"""
# Model options we want to compare and preserve in an AlterModelOptions op
ALTER_OPTION_KEYS = [
"base_manager_name",
"default_manager_name",
"default_related_name",
"get_latest_by",
"managed",
"ordering",
"permissions",
"default_permissions",
"select_on_save",
"verbose_name",
"verbose_name_plural",
]
def __init__(self, name, options):
self.options = options
super().__init__(name)
def deconstruct(self):
kwargs = {
'name': self.name,
'options': self.options,
}
return (
self.__class__.__qualname__,
[],
kwargs
)
def state_forwards(self, app_label, state):
model_state = state.models[app_label, self.name_lower]
model_state.options = {**model_state.options, **self.options}
for key in self.ALTER_OPTION_KEYS:
if key not in self.options:
model_state.options.pop(key, False)
state.reload_model(app_label, self.name_lower, delay=True)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
pass
def database_backwards(self, app_label, schema_editor, from_state, to_state):
pass
def describe(self):
return "Change Meta options on %s" % self.name
class AlterModelManagers(ModelOptionOperation):
"""Alter the model's managers."""
serialization_expand_args = ['managers']
def __init__(self, name, managers):
self.managers = managers
super().__init__(name)
def deconstruct(self):
return (
self.__class__.__qualname__,
[self.name, self.managers],
{}
)
def state_forwards(self, app_label, state):
model_state = state.models[app_label, self.name_lower]
model_state.managers = list(self.managers)
state.reload_model(app_label, self.name_lower, delay=True)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
pass
def database_backwards(self, app_label, schema_editor, from_state, to_state):
pass
def describe(self):
return "Change managers on %s" % self.name
class IndexOperation(Operation):
option_name = 'indexes'
@cached_property
def model_name_lower(self):
return self.model_name.lower()
class AddIndex(IndexOperation):
"""Add an index on a model."""
def __init__(self, model_name, index):
self.model_name = model_name
if not index.name:
raise ValueError(
"Indexes passed to AddIndex operations require a name "
"argument. %r doesn't have one." % index
)
self.index = index
def state_forwards(self, app_label, state):
model_state = state.models[app_label, self.model_name_lower]
model_state.options[self.option_name] = [*model_state.options[self.option_name], self.index.clone()]
state.reload_model(app_label, self.model_name_lower, delay=True)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
schema_editor.add_index(model, self.index)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
model = from_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
schema_editor.remove_index(model, self.index)
def deconstruct(self):
kwargs = {
'model_name': self.model_name,
'index': self.index,
}
return (
self.__class__.__qualname__,
[],
kwargs,
)
def describe(self):
return 'Create index %s on field(s) %s of model %s' % (
self.index.name,
', '.join(self.index.fields),
self.model_name,
)
class RemoveIndex(IndexOperation):
"""Remove an index from a model."""
def __init__(self, model_name, name):
self.model_name = model_name
self.name = name
def state_forwards(self, app_label, state):
model_state = state.models[app_label, self.model_name_lower]
indexes = model_state.options[self.option_name]
model_state.options[self.option_name] = [idx for idx in indexes if idx.name != self.name]
state.reload_model(app_label, self.model_name_lower, delay=True)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
model = from_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
from_model_state = from_state.models[app_label, self.model_name_lower]
index = from_model_state.get_index_by_name(self.name)
schema_editor.remove_index(model, index)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
to_model_state = to_state.models[app_label, self.model_name_lower]
index = to_model_state.get_index_by_name(self.name)
schema_editor.add_index(model, index)
def deconstruct(self):
kwargs = {
'model_name': self.model_name,
'name': self.name,
}
return (
self.__class__.__qualname__,
[],
kwargs,
)
def describe(self):
return 'Remove index %s from %s' % (self.name, self.model_name)
class AddConstraint(IndexOperation):
option_name = 'constraints'
def __init__(self, model_name, constraint):
self.model_name = model_name
self.constraint = constraint
def state_forwards(self, app_label, state):
model_state = state.models[app_label, self.model_name_lower]
model_state.options[self.option_name] = [*model_state.options[self.option_name], self.constraint]
state.reload_model(app_label, self.model_name_lower, delay=True)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
schema_editor.add_constraint(model, self.constraint)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
schema_editor.remove_constraint(model, self.constraint)
def deconstruct(self):
return self.__class__.__name__, [], {
'model_name': self.model_name,
'constraint': self.constraint,
}
def describe(self):
return 'Create constraint %s on model %s' % (self.constraint.name, self.model_name)
class RemoveConstraint(IndexOperation):
option_name = 'constraints'
def __init__(self, model_name, name):
self.model_name = model_name
self.name = name
def state_forwards(self, app_label, state):
model_state = state.models[app_label, self.model_name_lower]
constraints = model_state.options[self.option_name]
model_state.options[self.option_name] = [c for c in constraints if c.name != self.name]
state.reload_model(app_label, self.model_name_lower, delay=True)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
from_model_state = from_state.models[app_label, self.model_name_lower]
constraint = from_model_state.get_constraint_by_name(self.name)
schema_editor.remove_constraint(model, constraint)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
to_model_state = to_state.models[app_label, self.model_name_lower]
constraint = to_model_state.get_constraint_by_name(self.name)
schema_editor.add_constraint(model, constraint)
def deconstruct(self):
return self.__class__.__name__, [], {
'model_name': self.model_name,
'name': self.name,
}
def describe(self):
return 'Remove constraint %s from model %s' % (self.name, self.model_name)
|
cdec3ab0276eee543e3088d590d6c98ca5455b3fb8e8fe258543354ef05f0ccb | from django.db import router
class Operation:
"""
Base class for migration operations.
It's responsible for both mutating the in-memory model state
(see db/migrations/state.py) to represent what it performs, as well
as actually performing it against a live database.
Note that some operations won't modify memory state at all (e.g. data
copying operations), and some will need their modifications to be
optionally specified by the user (e.g. custom Python code snippets)
Due to the way this class deals with deconstruction, it should be
considered immutable.
"""
# If this migration can be run in reverse.
# Some operations are impossible to reverse, like deleting data.
reversible = True
# Can this migration be represented as SQL? (things like RunPython cannot)
reduces_to_sql = True
# Should this operation be forced as atomic even on backends with no
# DDL transaction support (i.e., does it have no DDL, like RunPython)
atomic = False
# Should this operation be considered safe to elide and optimize across?
elidable = False
serialization_expand_args = []
def __new__(cls, *args, **kwargs):
# We capture the arguments to make returning them trivial
self = object.__new__(cls)
self._constructor_args = (args, kwargs)
return self
def deconstruct(self):
"""
Return a 3-tuple of class import path (or just name if it lives
under django.db.migrations), positional arguments, and keyword
arguments.
"""
return (
self.__class__.__name__,
self._constructor_args[0],
self._constructor_args[1],
)
def state_forwards(self, app_label, state):
"""
Take the state from the previous migration, and mutate it
so that it matches what this migration would perform.
"""
raise NotImplementedError('subclasses of Operation must provide a state_forwards() method')
def database_forwards(self, app_label, schema_editor, from_state, to_state):
"""
Perform the mutation on the database schema in the normal
(forwards) direction.
"""
raise NotImplementedError('subclasses of Operation must provide a database_forwards() method')
def database_backwards(self, app_label, schema_editor, from_state, to_state):
"""
Perform the mutation on the database schema in the reverse
direction - e.g. if this were CreateModel, it would in fact
drop the model's table.
"""
raise NotImplementedError('subclasses of Operation must provide a database_backwards() method')
def describe(self):
"""
Output a brief summary of what the action does.
"""
return "%s: %s" % (self.__class__.__name__, self._constructor_args)
def references_model(self, name, app_label):
"""
Return True if there is a chance this operation references the given
model name (as a string), with an app label for accuracy.
Used for optimization. If in doubt, return True;
returning a false positive will merely make the optimizer a little
less efficient, while returning a false negative may result in an
unusable optimized migration.
"""
return True
def references_field(self, model_name, name, app_label):
"""
Return True if there is a chance this operation references the given
field name, with an app label for accuracy.
Used for optimization. If in doubt, return True.
"""
return self.references_model(model_name, app_label)
def allow_migrate_model(self, connection_alias, model):
"""
Return whether or not a model may be migrated.
This is a thin wrapper around router.allow_migrate_model() that
preemptively rejects any proxy, swapped out, or unmanaged model.
"""
if not model._meta.can_migrate(connection_alias):
return False
return router.allow_migrate_model(connection_alias, model)
def reduce(self, operation, app_label):
"""
Return either a list of operations the actual operation should be
replaced with or a boolean that indicates whether or not the specified
operation can be optimized across.
"""
if self.elidable:
return [operation]
elif operation.elidable:
return [self]
return False
def __repr__(self):
return "<%s %s%s>" % (
self.__class__.__name__,
", ".join(map(repr, self._constructor_args[0])),
",".join(" %s=%r" % x for x in self._constructor_args[1].items()),
)
|
45837529511b0e1a4d6a7c4cbd2a9f68cdae134edb9fd5da0aaf3823fa291705 | from django.core.exceptions import FieldDoesNotExist
from django.db.models import NOT_PROVIDED
from django.utils.functional import cached_property
from .base import Operation
from .utils import field_is_referenced, field_references, get_references
class FieldOperation(Operation):
def __init__(self, model_name, name, field=None):
self.model_name = model_name
self.name = name
self.field = field
@cached_property
def model_name_lower(self):
return self.model_name.lower()
@cached_property
def name_lower(self):
return self.name.lower()
def is_same_model_operation(self, operation):
return self.model_name_lower == operation.model_name_lower
def is_same_field_operation(self, operation):
return self.is_same_model_operation(operation) and self.name_lower == operation.name_lower
def references_model(self, name, app_label):
name_lower = name.lower()
if name_lower == self.model_name_lower:
return True
if self.field:
return bool(field_references(
(app_label, self.model_name_lower), self.field, (app_label, name_lower)
))
return False
def references_field(self, model_name, name, app_label):
model_name_lower = model_name.lower()
# Check if this operation locally references the field.
if model_name_lower == self.model_name_lower:
if name == self.name:
return True
elif self.field and hasattr(self.field, 'from_fields') and name in self.field.from_fields:
return True
# Check if this operation remotely references the field.
if self.field is None:
return False
return bool(field_references(
(app_label, self.model_name_lower),
self.field,
(app_label, model_name_lower),
name,
))
def reduce(self, operation, app_label):
return (
super().reduce(operation, app_label) or
not operation.references_field(self.model_name, self.name, app_label)
)
class AddField(FieldOperation):
"""Add a field to a model."""
def __init__(self, model_name, name, field, preserve_default=True):
self.preserve_default = preserve_default
super().__init__(model_name, name, field)
def deconstruct(self):
kwargs = {
'model_name': self.model_name,
'name': self.name,
'field': self.field,
}
if self.preserve_default is not True:
kwargs['preserve_default'] = self.preserve_default
return (
self.__class__.__name__,
[],
kwargs
)
def state_forwards(self, app_label, state):
# If preserve default is off, don't use the default for future state
if not self.preserve_default:
field = self.field.clone()
field.default = NOT_PROVIDED
else:
field = self.field
state.models[app_label, self.model_name_lower].fields[self.name] = field
# Delay rendering of relationships if it's not a relational field
delay = not field.is_relation
state.reload_model(app_label, self.model_name_lower, delay=delay)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
to_model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, to_model):
from_model = from_state.apps.get_model(app_label, self.model_name)
field = to_model._meta.get_field(self.name)
if not self.preserve_default:
field.default = self.field.default
schema_editor.add_field(
from_model,
field,
)
if not self.preserve_default:
field.default = NOT_PROVIDED
def database_backwards(self, app_label, schema_editor, from_state, to_state):
from_model = from_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, from_model):
schema_editor.remove_field(from_model, from_model._meta.get_field(self.name))
def describe(self):
return "Add field %s to %s" % (self.name, self.model_name)
def reduce(self, operation, app_label):
if isinstance(operation, FieldOperation) and self.is_same_field_operation(operation):
if isinstance(operation, AlterField):
return [
AddField(
model_name=self.model_name,
name=operation.name,
field=operation.field,
),
]
elif isinstance(operation, RemoveField):
return []
elif isinstance(operation, RenameField):
return [
AddField(
model_name=self.model_name,
name=operation.new_name,
field=self.field,
),
]
return super().reduce(operation, app_label)
class RemoveField(FieldOperation):
"""Remove a field from a model."""
def deconstruct(self):
kwargs = {
'model_name': self.model_name,
'name': self.name,
}
return (
self.__class__.__name__,
[],
kwargs
)
def state_forwards(self, app_label, state):
model_state = state.models[app_label, self.model_name_lower]
old_field = model_state.fields.pop(self.name)
# Delay rendering of relationships if it's not a relational field
delay = not old_field.is_relation
state.reload_model(app_label, self.model_name_lower, delay=delay)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
from_model = from_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, from_model):
schema_editor.remove_field(from_model, from_model._meta.get_field(self.name))
def database_backwards(self, app_label, schema_editor, from_state, to_state):
to_model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, to_model):
from_model = from_state.apps.get_model(app_label, self.model_name)
schema_editor.add_field(from_model, to_model._meta.get_field(self.name))
def describe(self):
return "Remove field %s from %s" % (self.name, self.model_name)
def reduce(self, operation, app_label):
from .models import DeleteModel
if isinstance(operation, DeleteModel) and operation.name_lower == self.model_name_lower:
return [operation]
return super().reduce(operation, app_label)
class AlterField(FieldOperation):
"""
Alter a field's database column (e.g. null, max_length) to the provided
new field.
"""
def __init__(self, model_name, name, field, preserve_default=True):
self.preserve_default = preserve_default
super().__init__(model_name, name, field)
def deconstruct(self):
kwargs = {
'model_name': self.model_name,
'name': self.name,
'field': self.field,
}
if self.preserve_default is not True:
kwargs['preserve_default'] = self.preserve_default
return (
self.__class__.__name__,
[],
kwargs
)
def state_forwards(self, app_label, state):
if not self.preserve_default:
field = self.field.clone()
field.default = NOT_PROVIDED
else:
field = self.field
model_state = state.models[app_label, self.model_name_lower]
model_state.fields[self.name] = field
# TODO: investigate if old relational fields must be reloaded or if it's
# sufficient if the new field is (#27737).
# Delay rendering of relationships if it's not a relational field and
# not referenced by a foreign key.
delay = (
not field.is_relation and
not field_is_referenced(
state, (app_label, self.model_name_lower), (self.name, field),
)
)
state.reload_model(app_label, self.model_name_lower, delay=delay)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
to_model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, to_model):
from_model = from_state.apps.get_model(app_label, self.model_name)
from_field = from_model._meta.get_field(self.name)
to_field = to_model._meta.get_field(self.name)
if not self.preserve_default:
to_field.default = self.field.default
schema_editor.alter_field(from_model, from_field, to_field)
if not self.preserve_default:
to_field.default = NOT_PROVIDED
def database_backwards(self, app_label, schema_editor, from_state, to_state):
self.database_forwards(app_label, schema_editor, from_state, to_state)
def describe(self):
return "Alter field %s on %s" % (self.name, self.model_name)
def reduce(self, operation, app_label):
if isinstance(operation, RemoveField) and self.is_same_field_operation(operation):
return [operation]
elif isinstance(operation, RenameField) and self.is_same_field_operation(operation):
return [
operation,
AlterField(
model_name=self.model_name,
name=operation.new_name,
field=self.field,
),
]
return super().reduce(operation, app_label)
class RenameField(FieldOperation):
"""Rename a field on the model. Might affect db_column too."""
def __init__(self, model_name, old_name, new_name):
self.old_name = old_name
self.new_name = new_name
super().__init__(model_name, old_name)
@cached_property
def old_name_lower(self):
return self.old_name.lower()
@cached_property
def new_name_lower(self):
return self.new_name.lower()
def deconstruct(self):
kwargs = {
'model_name': self.model_name,
'old_name': self.old_name,
'new_name': self.new_name,
}
return (
self.__class__.__name__,
[],
kwargs
)
def state_forwards(self, app_label, state):
model_state = state.models[app_label, self.model_name_lower]
# Rename the field
fields = model_state.fields
try:
found = fields.pop(self.old_name)
except KeyError:
raise FieldDoesNotExist(
"%s.%s has no field named '%s'" % (app_label, self.model_name, self.old_name)
)
fields[self.new_name] = found
for field in fields.values():
# Fix from_fields to refer to the new field.
from_fields = getattr(field, 'from_fields', None)
if from_fields:
field.from_fields = tuple([
self.new_name if from_field_name == self.old_name else from_field_name
for from_field_name in from_fields
])
# Fix index/unique_together to refer to the new field
options = model_state.options
for option in ('index_together', 'unique_together'):
if option in options:
options[option] = [
[self.new_name if n == self.old_name else n for n in together]
for together in options[option]
]
# Fix to_fields to refer to the new field.
delay = True
references = get_references(
state, (app_label, self.model_name_lower), (self.old_name, found),
)
for *_, field, reference in references:
delay = False
if reference.to:
remote_field, to_fields = reference.to
if getattr(remote_field, 'field_name', None) == self.old_name:
remote_field.field_name = self.new_name
if to_fields:
field.to_fields = tuple([
self.new_name if to_field_name == self.old_name else to_field_name
for to_field_name in to_fields
])
state.reload_model(app_label, self.model_name_lower, delay=delay)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
to_model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, to_model):
from_model = from_state.apps.get_model(app_label, self.model_name)
schema_editor.alter_field(
from_model,
from_model._meta.get_field(self.old_name),
to_model._meta.get_field(self.new_name),
)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
to_model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, to_model):
from_model = from_state.apps.get_model(app_label, self.model_name)
schema_editor.alter_field(
from_model,
from_model._meta.get_field(self.new_name),
to_model._meta.get_field(self.old_name),
)
def describe(self):
return "Rename field %s on %s to %s" % (self.old_name, self.model_name, self.new_name)
def references_field(self, model_name, name, app_label):
return self.references_model(model_name, app_label) and (
name.lower() == self.old_name_lower or
name.lower() == self.new_name_lower
)
def reduce(self, operation, app_label):
if (isinstance(operation, RenameField) and
self.is_same_model_operation(operation) and
self.new_name_lower == operation.old_name_lower):
return [
RenameField(
self.model_name,
self.old_name,
operation.new_name,
),
]
# Skip `FieldOperation.reduce` as we want to run `references_field`
# against self.new_name.
return (
super(FieldOperation, self).reduce(operation, app_label) or
not operation.references_field(self.model_name, self.new_name, app_label)
)
|
4fec83cc6b91f873c74ee1dde703ab4ea74d3fb27d51000ac06e4b59903b2a58 | from collections import namedtuple
from django.db.models.fields.related import RECURSIVE_RELATIONSHIP_CONSTANT
def resolve_relation(model, app_label=None, model_name=None):
"""
Turn a model class or model reference string and return a model tuple.
app_label and model_name are used to resolve the scope of recursive and
unscoped model relationship.
"""
if isinstance(model, str):
if model == RECURSIVE_RELATIONSHIP_CONSTANT:
if app_label is None or model_name is None:
raise TypeError(
'app_label and model_name must be provided to resolve '
'recursive relationships.'
)
return app_label, model_name
if '.' in model:
return tuple(model.lower().split('.', 1))
if app_label is None:
raise TypeError(
'app_label must be provided to resolve unscoped model '
'relationships.'
)
return app_label, model.lower()
return model._meta.app_label, model._meta.model_name
FieldReference = namedtuple('FieldReference', 'to through')
def field_references(
model_tuple,
field,
reference_model_tuple,
reference_field_name=None,
reference_field=None,
):
"""
Return either False or a FieldReference if `field` references provided
context.
False positives can be returned if `reference_field_name` is provided
without `reference_field` because of the introspection limitation it
incurs. This should not be an issue when this function is used to determine
whether or not an optimization can take place.
"""
remote_field = field.remote_field
if not remote_field:
return False
references_to = None
references_through = None
if resolve_relation(remote_field.model, *model_tuple) == reference_model_tuple:
to_fields = getattr(field, 'to_fields', None)
if (
reference_field_name is None or
# Unspecified to_field(s).
to_fields is None or
# Reference to primary key.
(None in to_fields and (reference_field is None or reference_field.primary_key)) or
# Reference to field.
reference_field_name in to_fields
):
references_to = (remote_field, to_fields)
through = getattr(remote_field, 'through', None)
if through and resolve_relation(through, *model_tuple) == reference_model_tuple:
through_fields = remote_field.through_fields
if (
reference_field_name is None or
# Unspecified through_fields.
through_fields is None or
# Reference to field.
reference_field_name in through_fields
):
references_through = (remote_field, through_fields)
if not (references_to or references_through):
return False
return FieldReference(references_to, references_through)
def get_references(state, model_tuple, field_tuple=()):
"""
Generator of (model_state, name, field, reference) referencing
provided context.
If field_tuple is provided only references to this particular field of
model_tuple will be generated.
"""
for state_model_tuple, model_state in state.models.items():
for name, field in model_state.fields.items():
reference = field_references(state_model_tuple, field, model_tuple, *field_tuple)
if reference:
yield model_state, name, field, reference
def field_is_referenced(state, model_tuple, field_tuple):
"""Return whether `field_tuple` is referenced by any state models."""
return next(get_references(state, model_tuple, field_tuple), None) is not None
|
95bb621d601a5da786fa6f6c49d5ee6a563d8db59513b8fd0fedf768dc64a25c | import collections.abc
import copy
import datetime
import decimal
import operator
import uuid
import warnings
from base64 import b64decode, b64encode
from functools import partialmethod, total_ordering
from django import forms
from django.apps import apps
from django.conf import settings
from django.core import checks, exceptions, validators
from django.db import connection, connections, router
from django.db.models.constants import LOOKUP_SEP
from django.db.models.query_utils import DeferredAttribute, RegisterLookupMixin
from django.utils import timezone
from django.utils.datastructures import DictWrapper
from django.utils.dateparse import (
parse_date, parse_datetime, parse_duration, parse_time,
)
from django.utils.duration import duration_microseconds, duration_string
from django.utils.functional import Promise, cached_property
from django.utils.ipv6 import clean_ipv6_address
from django.utils.itercompat import is_iterable
from django.utils.text import capfirst
from django.utils.translation import gettext_lazy as _
__all__ = [
'AutoField', 'BLANK_CHOICE_DASH', 'BigAutoField', 'BigIntegerField',
'BinaryField', 'BooleanField', 'CharField', 'CommaSeparatedIntegerField',
'DateField', 'DateTimeField', 'DecimalField', 'DurationField',
'EmailField', 'Empty', 'Field', 'FilePathField', 'FloatField',
'GenericIPAddressField', 'IPAddressField', 'IntegerField', 'NOT_PROVIDED',
'NullBooleanField', 'PositiveBigIntegerField', 'PositiveIntegerField',
'PositiveSmallIntegerField', 'SlugField', 'SmallAutoField',
'SmallIntegerField', 'TextField', 'TimeField', 'URLField', 'UUIDField',
]
class Empty:
pass
class NOT_PROVIDED:
pass
# The values to use for "blank" in SelectFields. Will be appended to the start
# of most "choices" lists.
BLANK_CHOICE_DASH = [("", "---------")]
def _load_field(app_label, model_name, field_name):
return apps.get_model(app_label, model_name)._meta.get_field(field_name)
# A guide to Field parameters:
#
# * name: The name of the field specified in the model.
# * attname: The attribute to use on the model object. This is the same as
# "name", except in the case of ForeignKeys, where "_id" is
# appended.
# * db_column: The db_column specified in the model (or None).
# * column: The database column for this field. This is the same as
# "attname", except if db_column is specified.
#
# Code that introspects values, or does other dynamic things, should use
# attname. For example, this gets the primary key value of object "obj":
#
# getattr(obj, opts.pk.attname)
def _empty(of_cls):
new = Empty()
new.__class__ = of_cls
return new
def return_None():
return None
@total_ordering
class Field(RegisterLookupMixin):
"""Base class for all field types"""
# Designates whether empty strings fundamentally are allowed at the
# database level.
empty_strings_allowed = True
empty_values = list(validators.EMPTY_VALUES)
# These track each time a Field instance is created. Used to retain order.
# The auto_creation_counter is used for fields that Django implicitly
# creates, creation_counter is used for all user-specified fields.
creation_counter = 0
auto_creation_counter = -1
default_validators = [] # Default set of validators
default_error_messages = {
'invalid_choice': _('Value %(value)r is not a valid choice.'),
'null': _('This field cannot be null.'),
'blank': _('This field cannot be blank.'),
'unique': _('%(model_name)s with this %(field_label)s '
'already exists.'),
# Translators: The 'lookup_type' is one of 'date', 'year' or 'month'.
# Eg: "Title must be unique for pub_date year"
'unique_for_date': _("%(field_label)s must be unique for "
"%(date_field_label)s %(lookup_type)s."),
}
system_check_deprecated_details = None
system_check_removed_details = None
# Field flags
hidden = False
many_to_many = None
many_to_one = None
one_to_many = None
one_to_one = None
related_model = None
descriptor_class = DeferredAttribute
# Generic field type description, usually overridden by subclasses
def _description(self):
return _('Field of type: %(field_type)s') % {
'field_type': self.__class__.__name__
}
description = property(_description)
def __init__(self, verbose_name=None, name=None, primary_key=False,
max_length=None, unique=False, blank=False, null=False,
db_index=False, rel=None, default=NOT_PROVIDED, editable=True,
serialize=True, unique_for_date=None, unique_for_month=None,
unique_for_year=None, choices=None, help_text='', db_column=None,
db_tablespace=None, auto_created=False, validators=(),
error_messages=None):
self.name = name
self.verbose_name = verbose_name # May be set by set_attributes_from_name
self._verbose_name = verbose_name # Store original for deconstruction
self.primary_key = primary_key
self.max_length, self._unique = max_length, unique
self.blank, self.null = blank, null
self.remote_field = rel
self.is_relation = self.remote_field is not None
self.default = default
self.editable = editable
self.serialize = serialize
self.unique_for_date = unique_for_date
self.unique_for_month = unique_for_month
self.unique_for_year = unique_for_year
if isinstance(choices, collections.abc.Iterator):
choices = list(choices)
self.choices = choices
self.help_text = help_text
self.db_index = db_index
self.db_column = db_column
self._db_tablespace = db_tablespace
self.auto_created = auto_created
# Adjust the appropriate creation counter, and save our local copy.
if auto_created:
self.creation_counter = Field.auto_creation_counter
Field.auto_creation_counter -= 1
else:
self.creation_counter = Field.creation_counter
Field.creation_counter += 1
self._validators = list(validators) # Store for deconstruction later
messages = {}
for c in reversed(self.__class__.__mro__):
messages.update(getattr(c, 'default_error_messages', {}))
messages.update(error_messages or {})
self._error_messages = error_messages # Store for deconstruction later
self.error_messages = messages
def __str__(self):
"""
Return "app_label.model_label.field_name" for fields attached to
models.
"""
if not hasattr(self, 'model'):
return super().__str__()
model = self.model
app = model._meta.app_label
return '%s.%s.%s' % (app, model._meta.object_name, self.name)
def __repr__(self):
"""Display the module, class, and name of the field."""
path = '%s.%s' % (self.__class__.__module__, self.__class__.__qualname__)
name = getattr(self, 'name', None)
if name is not None:
return '<%s: %s>' % (path, name)
return '<%s>' % path
def check(self, **kwargs):
return [
*self._check_field_name(),
*self._check_choices(),
*self._check_db_index(),
*self._check_null_allowed_for_primary_keys(),
*self._check_backend_specific_checks(**kwargs),
*self._check_validators(),
*self._check_deprecation_details(),
]
def _check_field_name(self):
"""
Check if field name is valid, i.e. 1) does not end with an
underscore, 2) does not contain "__" and 3) is not "pk".
"""
if self.name.endswith('_'):
return [
checks.Error(
'Field names must not end with an underscore.',
obj=self,
id='fields.E001',
)
]
elif LOOKUP_SEP in self.name:
return [
checks.Error(
'Field names must not contain "%s".' % LOOKUP_SEP,
obj=self,
id='fields.E002',
)
]
elif self.name == 'pk':
return [
checks.Error(
"'pk' is a reserved word that cannot be used as a field name.",
obj=self,
id='fields.E003',
)
]
else:
return []
@classmethod
def _choices_is_value(cls, value):
return isinstance(value, (str, Promise)) or not is_iterable(value)
def _check_choices(self):
if not self.choices:
return []
if not is_iterable(self.choices) or isinstance(self.choices, str):
return [
checks.Error(
"'choices' must be an iterable (e.g., a list or tuple).",
obj=self,
id='fields.E004',
)
]
choice_max_length = 0
# Expect [group_name, [value, display]]
for choices_group in self.choices:
try:
group_name, group_choices = choices_group
except (TypeError, ValueError):
# Containing non-pairs
break
try:
if not all(
self._choices_is_value(value) and self._choices_is_value(human_name)
for value, human_name in group_choices
):
break
if self.max_length is not None and group_choices:
choice_max_length = max([
choice_max_length,
*(len(value) for value, _ in group_choices if isinstance(value, str)),
])
except (TypeError, ValueError):
# No groups, choices in the form [value, display]
value, human_name = group_name, group_choices
if not self._choices_is_value(value) or not self._choices_is_value(human_name):
break
if self.max_length is not None and isinstance(value, str):
choice_max_length = max(choice_max_length, len(value))
# Special case: choices=['ab']
if isinstance(choices_group, str):
break
else:
if self.max_length is not None and choice_max_length > self.max_length:
return [
checks.Error(
"'max_length' is too small to fit the longest value "
"in 'choices' (%d characters)." % choice_max_length,
obj=self,
id='fields.E009',
),
]
return []
return [
checks.Error(
"'choices' must be an iterable containing "
"(actual value, human readable name) tuples.",
obj=self,
id='fields.E005',
)
]
def _check_db_index(self):
if self.db_index not in (None, True, False):
return [
checks.Error(
"'db_index' must be None, True or False.",
obj=self,
id='fields.E006',
)
]
else:
return []
def _check_null_allowed_for_primary_keys(self):
if (self.primary_key and self.null and
not connection.features.interprets_empty_strings_as_nulls):
# We cannot reliably check this for backends like Oracle which
# consider NULL and '' to be equal (and thus set up
# character-based fields a little differently).
return [
checks.Error(
'Primary keys must not have null=True.',
hint=('Set null=False on the field, or '
'remove primary_key=True argument.'),
obj=self,
id='fields.E007',
)
]
else:
return []
def _check_backend_specific_checks(self, databases=None, **kwargs):
if databases is None:
return []
app_label = self.model._meta.app_label
errors = []
for alias in databases:
if router.allow_migrate(alias, app_label, model_name=self.model._meta.model_name):
errors.extend(connections[alias].validation.check_field(self, **kwargs))
return errors
def _check_validators(self):
errors = []
for i, validator in enumerate(self.validators):
if not callable(validator):
errors.append(
checks.Error(
"All 'validators' must be callable.",
hint=(
"validators[{i}] ({repr}) isn't a function or "
"instance of a validator class.".format(
i=i, repr=repr(validator),
)
),
obj=self,
id='fields.E008',
)
)
return errors
def _check_deprecation_details(self):
if self.system_check_removed_details is not None:
return [
checks.Error(
self.system_check_removed_details.get(
'msg',
'%s has been removed except for support in historical '
'migrations.' % self.__class__.__name__
),
hint=self.system_check_removed_details.get('hint'),
obj=self,
id=self.system_check_removed_details.get('id', 'fields.EXXX'),
)
]
elif self.system_check_deprecated_details is not None:
return [
checks.Warning(
self.system_check_deprecated_details.get(
'msg',
'%s has been deprecated.' % self.__class__.__name__
),
hint=self.system_check_deprecated_details.get('hint'),
obj=self,
id=self.system_check_deprecated_details.get('id', 'fields.WXXX'),
)
]
return []
def get_col(self, alias, output_field=None):
if output_field is None:
output_field = self
if alias != self.model._meta.db_table or output_field != self:
from django.db.models.expressions import Col
return Col(alias, self, output_field)
else:
return self.cached_col
@cached_property
def cached_col(self):
from django.db.models.expressions import Col
return Col(self.model._meta.db_table, self)
def select_format(self, compiler, sql, params):
"""
Custom format for select clauses. For example, GIS columns need to be
selected as AsText(table.col) on MySQL as the table.col data can't be
used by Django.
"""
return sql, params
def deconstruct(self):
"""
Return enough information to recreate the field as a 4-tuple:
* The name of the field on the model, if contribute_to_class() has
been run.
* The import path of the field, including the class:e.g.
django.db.models.IntegerField This should be the most portable
version, so less specific may be better.
* A list of positional arguments.
* A dict of keyword arguments.
Note that the positional or keyword arguments must contain values of
the following types (including inner values of collection types):
* None, bool, str, int, float, complex, set, frozenset, list, tuple,
dict
* UUID
* datetime.datetime (naive), datetime.date
* top-level classes, top-level functions - will be referenced by their
full import path
* Storage instances - these have their own deconstruct() method
This is because the values here must be serialized into a text format
(possibly new Python code, possibly JSON) and these are the only types
with encoding handlers defined.
There's no need to return the exact way the field was instantiated this
time, just ensure that the resulting field is the same - prefer keyword
arguments over positional ones, and omit parameters with their default
values.
"""
# Short-form way of fetching all the default parameters
keywords = {}
possibles = {
"verbose_name": None,
"primary_key": False,
"max_length": None,
"unique": False,
"blank": False,
"null": False,
"db_index": False,
"default": NOT_PROVIDED,
"editable": True,
"serialize": True,
"unique_for_date": None,
"unique_for_month": None,
"unique_for_year": None,
"choices": None,
"help_text": '',
"db_column": None,
"db_tablespace": None,
"auto_created": False,
"validators": [],
"error_messages": None,
}
attr_overrides = {
"unique": "_unique",
"error_messages": "_error_messages",
"validators": "_validators",
"verbose_name": "_verbose_name",
"db_tablespace": "_db_tablespace",
}
equals_comparison = {"choices", "validators"}
for name, default in possibles.items():
value = getattr(self, attr_overrides.get(name, name))
# Unroll anything iterable for choices into a concrete list
if name == "choices" and isinstance(value, collections.abc.Iterable):
value = list(value)
# Do correct kind of comparison
if name in equals_comparison:
if value != default:
keywords[name] = value
else:
if value is not default:
keywords[name] = value
# Work out path - we shorten it for known Django core fields
path = "%s.%s" % (self.__class__.__module__, self.__class__.__qualname__)
if path.startswith("django.db.models.fields.related"):
path = path.replace("django.db.models.fields.related", "django.db.models")
elif path.startswith("django.db.models.fields.files"):
path = path.replace("django.db.models.fields.files", "django.db.models")
elif path.startswith('django.db.models.fields.json'):
path = path.replace('django.db.models.fields.json', 'django.db.models')
elif path.startswith("django.db.models.fields.proxy"):
path = path.replace("django.db.models.fields.proxy", "django.db.models")
elif path.startswith("django.db.models.fields"):
path = path.replace("django.db.models.fields", "django.db.models")
# Return basic info - other fields should override this.
return (self.name, path, [], keywords)
def clone(self):
"""
Uses deconstruct() to clone a new copy of this Field.
Will not preserve any class attachments/attribute names.
"""
name, path, args, kwargs = self.deconstruct()
return self.__class__(*args, **kwargs)
def __eq__(self, other):
# Needed for @total_ordering
if isinstance(other, Field):
return self.creation_counter == other.creation_counter
return NotImplemented
def __lt__(self, other):
# This is needed because bisect does not take a comparison function.
if isinstance(other, Field):
return self.creation_counter < other.creation_counter
return NotImplemented
def __hash__(self):
return hash(self.creation_counter)
def __deepcopy__(self, memodict):
# We don't have to deepcopy very much here, since most things are not
# intended to be altered after initial creation.
obj = copy.copy(self)
if self.remote_field:
obj.remote_field = copy.copy(self.remote_field)
if hasattr(self.remote_field, 'field') and self.remote_field.field is self:
obj.remote_field.field = obj
memodict[id(self)] = obj
return obj
def __copy__(self):
# We need to avoid hitting __reduce__, so define this
# slightly weird copy construct.
obj = Empty()
obj.__class__ = self.__class__
obj.__dict__ = self.__dict__.copy()
return obj
def __reduce__(self):
"""
Pickling should return the model._meta.fields instance of the field,
not a new copy of that field. So, use the app registry to load the
model and then the field back.
"""
if not hasattr(self, 'model'):
# Fields are sometimes used without attaching them to models (for
# example in aggregation). In this case give back a plain field
# instance. The code below will create a new empty instance of
# class self.__class__, then update its dict with self.__dict__
# values - so, this is very close to normal pickle.
state = self.__dict__.copy()
# The _get_default cached_property can't be pickled due to lambda
# usage.
state.pop('_get_default', None)
return _empty, (self.__class__,), state
return _load_field, (self.model._meta.app_label, self.model._meta.object_name,
self.name)
def get_pk_value_on_save(self, instance):
"""
Hook to generate new PK values on save. This method is called when
saving instances with no primary key value set. If this method returns
something else than None, then the returned value is used when saving
the new instance.
"""
if self.default:
return self.get_default()
return None
def to_python(self, value):
"""
Convert the input value into the expected Python data type, raising
django.core.exceptions.ValidationError if the data can't be converted.
Return the converted value. Subclasses should override this.
"""
return value
@cached_property
def validators(self):
"""
Some validators can't be created at field initialization time.
This method provides a way to delay their creation until required.
"""
return [*self.default_validators, *self._validators]
def run_validators(self, value):
if value in self.empty_values:
return
errors = []
for v in self.validators:
try:
v(value)
except exceptions.ValidationError as e:
if hasattr(e, 'code') and e.code in self.error_messages:
e.message = self.error_messages[e.code]
errors.extend(e.error_list)
if errors:
raise exceptions.ValidationError(errors)
def validate(self, value, model_instance):
"""
Validate value and raise ValidationError if necessary. Subclasses
should override this to provide validation logic.
"""
if not self.editable:
# Skip validation for non-editable fields.
return
if self.choices is not None and value not in self.empty_values:
for option_key, option_value in self.choices:
if isinstance(option_value, (list, tuple)):
# This is an optgroup, so look inside the group for
# options.
for optgroup_key, optgroup_value in option_value:
if value == optgroup_key:
return
elif value == option_key:
return
raise exceptions.ValidationError(
self.error_messages['invalid_choice'],
code='invalid_choice',
params={'value': value},
)
if value is None and not self.null:
raise exceptions.ValidationError(self.error_messages['null'], code='null')
if not self.blank and value in self.empty_values:
raise exceptions.ValidationError(self.error_messages['blank'], code='blank')
def clean(self, value, model_instance):
"""
Convert the value's type and run validation. Validation errors
from to_python() and validate() are propagated. Return the correct
value if no error is raised.
"""
value = self.to_python(value)
self.validate(value, model_instance)
self.run_validators(value)
return value
def db_type_parameters(self, connection):
return DictWrapper(self.__dict__, connection.ops.quote_name, 'qn_')
def db_check(self, connection):
"""
Return the database column check constraint for this field, for the
provided connection. Works the same way as db_type() for the case that
get_internal_type() does not map to a preexisting model field.
"""
data = self.db_type_parameters(connection)
try:
return connection.data_type_check_constraints[self.get_internal_type()] % data
except KeyError:
return None
def db_type(self, connection):
"""
Return the database column data type for this field, for the provided
connection.
"""
# The default implementation of this method looks at the
# backend-specific data_types dictionary, looking up the field by its
# "internal type".
#
# A Field class can implement the get_internal_type() method to specify
# which *preexisting* Django Field class it's most similar to -- i.e.,
# a custom field might be represented by a TEXT column type, which is
# the same as the TextField Django field type, which means the custom
# field's get_internal_type() returns 'TextField'.
#
# But the limitation of the get_internal_type() / data_types approach
# is that it cannot handle database column types that aren't already
# mapped to one of the built-in Django field types. In this case, you
# can implement db_type() instead of get_internal_type() to specify
# exactly which wacky database column type you want to use.
data = self.db_type_parameters(connection)
try:
return connection.data_types[self.get_internal_type()] % data
except KeyError:
return None
def rel_db_type(self, connection):
"""
Return the data type that a related field pointing to this field should
use. For example, this method is called by ForeignKey and OneToOneField
to determine its data type.
"""
return self.db_type(connection)
def cast_db_type(self, connection):
"""Return the data type to use in the Cast() function."""
db_type = connection.ops.cast_data_types.get(self.get_internal_type())
if db_type:
return db_type % self.db_type_parameters(connection)
return self.db_type(connection)
def db_parameters(self, connection):
"""
Extension of db_type(), providing a range of different return values
(type, checks). This will look at db_type(), allowing custom model
fields to override it.
"""
type_string = self.db_type(connection)
check_string = self.db_check(connection)
return {
"type": type_string,
"check": check_string,
}
def db_type_suffix(self, connection):
return connection.data_types_suffix.get(self.get_internal_type())
def get_db_converters(self, connection):
if hasattr(self, 'from_db_value'):
return [self.from_db_value]
return []
@property
def unique(self):
return self._unique or self.primary_key
@property
def db_tablespace(self):
return self._db_tablespace or settings.DEFAULT_INDEX_TABLESPACE
@property
def db_returning(self):
"""
Private API intended only to be used by Django itself. Currently only
the PostgreSQL backend supports returning multiple fields on a model.
"""
return False
def set_attributes_from_name(self, name):
self.name = self.name or name
self.attname, self.column = self.get_attname_column()
self.concrete = self.column is not None
if self.verbose_name is None and self.name:
self.verbose_name = self.name.replace('_', ' ')
def contribute_to_class(self, cls, name, private_only=False):
"""
Register the field with the model class it belongs to.
If private_only is True, create a separate instance of this field
for every subclass of cls, even if cls is not an abstract model.
"""
self.set_attributes_from_name(name)
self.model = cls
cls._meta.add_field(self, private=private_only)
if self.column:
# Don't override classmethods with the descriptor. This means that
# if you have a classmethod and a field with the same name, then
# such fields can't be deferred (we don't have a check for this).
if not getattr(cls, self.attname, None):
setattr(cls, self.attname, self.descriptor_class(self))
if self.choices is not None:
# Don't override a get_FOO_display() method defined explicitly on
# this class, but don't check methods derived from inheritance, to
# allow overriding inherited choices. For more complex inheritance
# structures users should override contribute_to_class().
if 'get_%s_display' % self.name not in cls.__dict__:
setattr(
cls,
'get_%s_display' % self.name,
partialmethod(cls._get_FIELD_display, field=self),
)
def get_filter_kwargs_for_object(self, obj):
"""
Return a dict that when passed as kwargs to self.model.filter(), would
yield all instances having the same value for this field as obj has.
"""
return {self.name: getattr(obj, self.attname)}
def get_attname(self):
return self.name
def get_attname_column(self):
attname = self.get_attname()
column = self.db_column or attname
return attname, column
def get_internal_type(self):
return self.__class__.__name__
def pre_save(self, model_instance, add):
"""Return field's value just before saving."""
return getattr(model_instance, self.attname)
def get_prep_value(self, value):
"""Perform preliminary non-db specific value checks and conversions."""
if isinstance(value, Promise):
value = value._proxy____cast()
return value
def get_db_prep_value(self, value, connection, prepared=False):
"""
Return field's value prepared for interacting with the database backend.
Used by the default implementations of get_db_prep_save().
"""
if not prepared:
value = self.get_prep_value(value)
return value
def get_db_prep_save(self, value, connection):
"""Return field's value prepared for saving into a database."""
return self.get_db_prep_value(value, connection=connection, prepared=False)
def has_default(self):
"""Return a boolean of whether this field has a default value."""
return self.default is not NOT_PROVIDED
def get_default(self):
"""Return the default value for this field."""
return self._get_default()
@cached_property
def _get_default(self):
if self.has_default():
if callable(self.default):
return self.default
return lambda: self.default
if not self.empty_strings_allowed or self.null and not connection.features.interprets_empty_strings_as_nulls:
return return_None
return str # return empty string
def get_choices(self, include_blank=True, blank_choice=BLANK_CHOICE_DASH, limit_choices_to=None, ordering=()):
"""
Return choices with a default blank choices included, for use
as <select> choices for this field.
"""
if self.choices is not None:
choices = list(self.choices)
if include_blank:
blank_defined = any(choice in ('', None) for choice, _ in self.flatchoices)
if not blank_defined:
choices = blank_choice + choices
return choices
rel_model = self.remote_field.model
limit_choices_to = limit_choices_to or self.get_limit_choices_to()
choice_func = operator.attrgetter(
self.remote_field.get_related_field().attname
if hasattr(self.remote_field, 'get_related_field')
else 'pk'
)
qs = rel_model._default_manager.complex_filter(limit_choices_to)
if ordering:
qs = qs.order_by(*ordering)
return (blank_choice if include_blank else []) + [
(choice_func(x), str(x)) for x in qs
]
def value_to_string(self, obj):
"""
Return a string value of this field from the passed obj.
This is used by the serialization framework.
"""
return str(self.value_from_object(obj))
def _get_flatchoices(self):
"""Flattened version of choices tuple."""
if self.choices is None:
return []
flat = []
for choice, value in self.choices:
if isinstance(value, (list, tuple)):
flat.extend(value)
else:
flat.append((choice, value))
return flat
flatchoices = property(_get_flatchoices)
def save_form_data(self, instance, data):
setattr(instance, self.name, data)
def formfield(self, form_class=None, choices_form_class=None, **kwargs):
"""Return a django.forms.Field instance for this field."""
defaults = {
'required': not self.blank,
'label': capfirst(self.verbose_name),
'help_text': self.help_text,
}
if self.has_default():
if callable(self.default):
defaults['initial'] = self.default
defaults['show_hidden_initial'] = True
else:
defaults['initial'] = self.get_default()
if self.choices is not None:
# Fields with choices get special treatment.
include_blank = (self.blank or
not (self.has_default() or 'initial' in kwargs))
defaults['choices'] = self.get_choices(include_blank=include_blank)
defaults['coerce'] = self.to_python
if self.null:
defaults['empty_value'] = None
if choices_form_class is not None:
form_class = choices_form_class
else:
form_class = forms.TypedChoiceField
# Many of the subclass-specific formfield arguments (min_value,
# max_value) don't apply for choice fields, so be sure to only pass
# the values that TypedChoiceField will understand.
for k in list(kwargs):
if k not in ('coerce', 'empty_value', 'choices', 'required',
'widget', 'label', 'initial', 'help_text',
'error_messages', 'show_hidden_initial', 'disabled'):
del kwargs[k]
defaults.update(kwargs)
if form_class is None:
form_class = forms.CharField
return form_class(**defaults)
def value_from_object(self, obj):
"""Return the value of this field in the given model instance."""
return getattr(obj, self.attname)
class BooleanField(Field):
empty_strings_allowed = False
default_error_messages = {
'invalid': _('“%(value)s” value must be either True or False.'),
'invalid_nullable': _('“%(value)s” value must be either True, False, or None.'),
}
description = _("Boolean (Either True or False)")
def get_internal_type(self):
return "BooleanField"
def to_python(self, value):
if self.null and value in self.empty_values:
return None
if value in (True, False):
# 1/0 are equal to True/False. bool() converts former to latter.
return bool(value)
if value in ('t', 'True', '1'):
return True
if value in ('f', 'False', '0'):
return False
raise exceptions.ValidationError(
self.error_messages['invalid_nullable' if self.null else 'invalid'],
code='invalid',
params={'value': value},
)
def get_prep_value(self, value):
value = super().get_prep_value(value)
if value is None:
return None
return self.to_python(value)
def formfield(self, **kwargs):
if self.choices is not None:
include_blank = not (self.has_default() or 'initial' in kwargs)
defaults = {'choices': self.get_choices(include_blank=include_blank)}
else:
form_class = forms.NullBooleanField if self.null else forms.BooleanField
# In HTML checkboxes, 'required' means "must be checked" which is
# different from the choices case ("must select some value").
# required=False allows unchecked checkboxes.
defaults = {'form_class': form_class, 'required': False}
return super().formfield(**{**defaults, **kwargs})
class CharField(Field):
description = _("String (up to %(max_length)s)")
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.validators.append(validators.MaxLengthValidator(self.max_length))
def check(self, **kwargs):
return [
*super().check(**kwargs),
*self._check_max_length_attribute(**kwargs),
]
def _check_max_length_attribute(self, **kwargs):
if self.max_length is None:
return [
checks.Error(
"CharFields must define a 'max_length' attribute.",
obj=self,
id='fields.E120',
)
]
elif (not isinstance(self.max_length, int) or isinstance(self.max_length, bool) or
self.max_length <= 0):
return [
checks.Error(
"'max_length' must be a positive integer.",
obj=self,
id='fields.E121',
)
]
else:
return []
def cast_db_type(self, connection):
if self.max_length is None:
return connection.ops.cast_char_field_without_max_length
return super().cast_db_type(connection)
def get_internal_type(self):
return "CharField"
def to_python(self, value):
if isinstance(value, str) or value is None:
return value
return str(value)
def get_prep_value(self, value):
value = super().get_prep_value(value)
return self.to_python(value)
def formfield(self, **kwargs):
# Passing max_length to forms.CharField means that the value's length
# will be validated twice. This is considered acceptable since we want
# the value in the form field (to pass into widget for example).
defaults = {'max_length': self.max_length}
# TODO: Handle multiple backends with different feature flags.
if self.null and not connection.features.interprets_empty_strings_as_nulls:
defaults['empty_value'] = None
defaults.update(kwargs)
return super().formfield(**defaults)
class CommaSeparatedIntegerField(CharField):
default_validators = [validators.validate_comma_separated_integer_list]
description = _("Comma-separated integers")
system_check_removed_details = {
'msg': (
'CommaSeparatedIntegerField is removed except for support in '
'historical migrations.'
),
'hint': (
'Use CharField(validators=[validate_comma_separated_integer_list]) '
'instead.'
),
'id': 'fields.E901',
}
class DateTimeCheckMixin:
def check(self, **kwargs):
return [
*super().check(**kwargs),
*self._check_mutually_exclusive_options(),
*self._check_fix_default_value(),
]
def _check_mutually_exclusive_options(self):
# auto_now, auto_now_add, and default are mutually exclusive
# options. The use of more than one of these options together
# will trigger an Error
mutually_exclusive_options = [self.auto_now_add, self.auto_now, self.has_default()]
enabled_options = [option not in (None, False) for option in mutually_exclusive_options].count(True)
if enabled_options > 1:
return [
checks.Error(
"The options auto_now, auto_now_add, and default "
"are mutually exclusive. Only one of these options "
"may be present.",
obj=self,
id='fields.E160',
)
]
else:
return []
def _check_fix_default_value(self):
return []
class DateField(DateTimeCheckMixin, Field):
empty_strings_allowed = False
default_error_messages = {
'invalid': _('“%(value)s” value has an invalid date format. It must be '
'in YYYY-MM-DD format.'),
'invalid_date': _('“%(value)s” value has the correct format (YYYY-MM-DD) '
'but it is an invalid date.'),
}
description = _("Date (without time)")
def __init__(self, verbose_name=None, name=None, auto_now=False,
auto_now_add=False, **kwargs):
self.auto_now, self.auto_now_add = auto_now, auto_now_add
if auto_now or auto_now_add:
kwargs['editable'] = False
kwargs['blank'] = True
super().__init__(verbose_name, name, **kwargs)
def _check_fix_default_value(self):
"""
Warn that using an actual date or datetime value is probably wrong;
it's only evaluated on server startup.
"""
if not self.has_default():
return []
now = timezone.now()
if not timezone.is_naive(now):
now = timezone.make_naive(now, timezone.utc)
value = self.default
if isinstance(value, datetime.datetime):
if not timezone.is_naive(value):
value = timezone.make_naive(value, timezone.utc)
value = value.date()
elif isinstance(value, datetime.date):
# Nothing to do, as dates don't have tz information
pass
else:
# No explicit date / datetime value -- no checks necessary
return []
offset = datetime.timedelta(days=1)
lower = (now - offset).date()
upper = (now + offset).date()
if lower <= value <= upper:
return [
checks.Warning(
'Fixed default value provided.',
hint='It seems you set a fixed date / time / datetime '
'value as default for this field. This may not be '
'what you want. If you want to have the current date '
'as default, use `django.utils.timezone.now`',
obj=self,
id='fields.W161',
)
]
return []
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if self.auto_now:
kwargs['auto_now'] = True
if self.auto_now_add:
kwargs['auto_now_add'] = True
if self.auto_now or self.auto_now_add:
del kwargs['editable']
del kwargs['blank']
return name, path, args, kwargs
def get_internal_type(self):
return "DateField"
def to_python(self, value):
if value is None:
return value
if isinstance(value, datetime.datetime):
if settings.USE_TZ and timezone.is_aware(value):
# Convert aware datetimes to the default time zone
# before casting them to dates (#17742).
default_timezone = timezone.get_default_timezone()
value = timezone.make_naive(value, default_timezone)
return value.date()
if isinstance(value, datetime.date):
return value
try:
parsed = parse_date(value)
if parsed is not None:
return parsed
except ValueError:
raise exceptions.ValidationError(
self.error_messages['invalid_date'],
code='invalid_date',
params={'value': value},
)
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={'value': value},
)
def pre_save(self, model_instance, add):
if self.auto_now or (self.auto_now_add and add):
value = datetime.date.today()
setattr(model_instance, self.attname, value)
return value
else:
return super().pre_save(model_instance, add)
def contribute_to_class(self, cls, name, **kwargs):
super().contribute_to_class(cls, name, **kwargs)
if not self.null:
setattr(
cls, 'get_next_by_%s' % self.name,
partialmethod(cls._get_next_or_previous_by_FIELD, field=self, is_next=True)
)
setattr(
cls, 'get_previous_by_%s' % self.name,
partialmethod(cls._get_next_or_previous_by_FIELD, field=self, is_next=False)
)
def get_prep_value(self, value):
value = super().get_prep_value(value)
return self.to_python(value)
def get_db_prep_value(self, value, connection, prepared=False):
# Casts dates into the format expected by the backend
if not prepared:
value = self.get_prep_value(value)
return connection.ops.adapt_datefield_value(value)
def value_to_string(self, obj):
val = self.value_from_object(obj)
return '' if val is None else val.isoformat()
def formfield(self, **kwargs):
return super().formfield(**{
'form_class': forms.DateField,
**kwargs,
})
class DateTimeField(DateField):
empty_strings_allowed = False
default_error_messages = {
'invalid': _('“%(value)s” value has an invalid format. It must be in '
'YYYY-MM-DD HH:MM[:ss[.uuuuuu]][TZ] format.'),
'invalid_date': _("“%(value)s” value has the correct format "
"(YYYY-MM-DD) but it is an invalid date."),
'invalid_datetime': _('“%(value)s” value has the correct format '
'(YYYY-MM-DD HH:MM[:ss[.uuuuuu]][TZ]) '
'but it is an invalid date/time.'),
}
description = _("Date (with time)")
# __init__ is inherited from DateField
def _check_fix_default_value(self):
"""
Warn that using an actual date or datetime value is probably wrong;
it's only evaluated on server startup.
"""
if not self.has_default():
return []
now = timezone.now()
if not timezone.is_naive(now):
now = timezone.make_naive(now, timezone.utc)
value = self.default
if isinstance(value, datetime.datetime):
second_offset = datetime.timedelta(seconds=10)
lower = now - second_offset
upper = now + second_offset
if timezone.is_aware(value):
value = timezone.make_naive(value, timezone.utc)
elif isinstance(value, datetime.date):
second_offset = datetime.timedelta(seconds=10)
lower = now - second_offset
lower = datetime.datetime(lower.year, lower.month, lower.day)
upper = now + second_offset
upper = datetime.datetime(upper.year, upper.month, upper.day)
value = datetime.datetime(value.year, value.month, value.day)
else:
# No explicit date / datetime value -- no checks necessary
return []
if lower <= value <= upper:
return [
checks.Warning(
'Fixed default value provided.',
hint='It seems you set a fixed date / time / datetime '
'value as default for this field. This may not be '
'what you want. If you want to have the current date '
'as default, use `django.utils.timezone.now`',
obj=self,
id='fields.W161',
)
]
return []
def get_internal_type(self):
return "DateTimeField"
def to_python(self, value):
if value is None:
return value
if isinstance(value, datetime.datetime):
return value
if isinstance(value, datetime.date):
value = datetime.datetime(value.year, value.month, value.day)
if settings.USE_TZ:
# For backwards compatibility, interpret naive datetimes in
# local time. This won't work during DST change, but we can't
# do much about it, so we let the exceptions percolate up the
# call stack.
warnings.warn("DateTimeField %s.%s received a naive datetime "
"(%s) while time zone support is active." %
(self.model.__name__, self.name, value),
RuntimeWarning)
default_timezone = timezone.get_default_timezone()
value = timezone.make_aware(value, default_timezone)
return value
try:
parsed = parse_datetime(value)
if parsed is not None:
return parsed
except ValueError:
raise exceptions.ValidationError(
self.error_messages['invalid_datetime'],
code='invalid_datetime',
params={'value': value},
)
try:
parsed = parse_date(value)
if parsed is not None:
return datetime.datetime(parsed.year, parsed.month, parsed.day)
except ValueError:
raise exceptions.ValidationError(
self.error_messages['invalid_date'],
code='invalid_date',
params={'value': value},
)
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={'value': value},
)
def pre_save(self, model_instance, add):
if self.auto_now or (self.auto_now_add and add):
value = timezone.now()
setattr(model_instance, self.attname, value)
return value
else:
return super().pre_save(model_instance, add)
# contribute_to_class is inherited from DateField, it registers
# get_next_by_FOO and get_prev_by_FOO
def get_prep_value(self, value):
value = super().get_prep_value(value)
value = self.to_python(value)
if value is not None and settings.USE_TZ and timezone.is_naive(value):
# For backwards compatibility, interpret naive datetimes in local
# time. This won't work during DST change, but we can't do much
# about it, so we let the exceptions percolate up the call stack.
try:
name = '%s.%s' % (self.model.__name__, self.name)
except AttributeError:
name = '(unbound)'
warnings.warn("DateTimeField %s received a naive datetime (%s)"
" while time zone support is active." %
(name, value),
RuntimeWarning)
default_timezone = timezone.get_default_timezone()
value = timezone.make_aware(value, default_timezone)
return value
def get_db_prep_value(self, value, connection, prepared=False):
# Casts datetimes into the format expected by the backend
if not prepared:
value = self.get_prep_value(value)
return connection.ops.adapt_datetimefield_value(value)
def value_to_string(self, obj):
val = self.value_from_object(obj)
return '' if val is None else val.isoformat()
def formfield(self, **kwargs):
return super().formfield(**{
'form_class': forms.DateTimeField,
**kwargs,
})
class DecimalField(Field):
empty_strings_allowed = False
default_error_messages = {
'invalid': _('“%(value)s” value must be a decimal number.'),
}
description = _("Decimal number")
def __init__(self, verbose_name=None, name=None, max_digits=None,
decimal_places=None, **kwargs):
self.max_digits, self.decimal_places = max_digits, decimal_places
super().__init__(verbose_name, name, **kwargs)
def check(self, **kwargs):
errors = super().check(**kwargs)
digits_errors = [
*self._check_decimal_places(),
*self._check_max_digits(),
]
if not digits_errors:
errors.extend(self._check_decimal_places_and_max_digits(**kwargs))
else:
errors.extend(digits_errors)
return errors
def _check_decimal_places(self):
try:
decimal_places = int(self.decimal_places)
if decimal_places < 0:
raise ValueError()
except TypeError:
return [
checks.Error(
"DecimalFields must define a 'decimal_places' attribute.",
obj=self,
id='fields.E130',
)
]
except ValueError:
return [
checks.Error(
"'decimal_places' must be a non-negative integer.",
obj=self,
id='fields.E131',
)
]
else:
return []
def _check_max_digits(self):
try:
max_digits = int(self.max_digits)
if max_digits <= 0:
raise ValueError()
except TypeError:
return [
checks.Error(
"DecimalFields must define a 'max_digits' attribute.",
obj=self,
id='fields.E132',
)
]
except ValueError:
return [
checks.Error(
"'max_digits' must be a positive integer.",
obj=self,
id='fields.E133',
)
]
else:
return []
def _check_decimal_places_and_max_digits(self, **kwargs):
if int(self.decimal_places) > int(self.max_digits):
return [
checks.Error(
"'max_digits' must be greater or equal to 'decimal_places'.",
obj=self,
id='fields.E134',
)
]
return []
@cached_property
def validators(self):
return super().validators + [
validators.DecimalValidator(self.max_digits, self.decimal_places)
]
@cached_property
def context(self):
return decimal.Context(prec=self.max_digits)
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if self.max_digits is not None:
kwargs['max_digits'] = self.max_digits
if self.decimal_places is not None:
kwargs['decimal_places'] = self.decimal_places
return name, path, args, kwargs
def get_internal_type(self):
return "DecimalField"
def to_python(self, value):
if value is None:
return value
if isinstance(value, float):
return self.context.create_decimal_from_float(value)
try:
return decimal.Decimal(value)
except decimal.InvalidOperation:
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={'value': value},
)
def get_db_prep_save(self, value, connection):
return connection.ops.adapt_decimalfield_value(self.to_python(value), self.max_digits, self.decimal_places)
def get_prep_value(self, value):
value = super().get_prep_value(value)
return self.to_python(value)
def formfield(self, **kwargs):
return super().formfield(**{
'max_digits': self.max_digits,
'decimal_places': self.decimal_places,
'form_class': forms.DecimalField,
**kwargs,
})
class DurationField(Field):
"""
Store timedelta objects.
Use interval on PostgreSQL, INTERVAL DAY TO SECOND on Oracle, and bigint
of microseconds on other databases.
"""
empty_strings_allowed = False
default_error_messages = {
'invalid': _('“%(value)s” value has an invalid format. It must be in '
'[DD] [[HH:]MM:]ss[.uuuuuu] format.')
}
description = _("Duration")
def get_internal_type(self):
return "DurationField"
def to_python(self, value):
if value is None:
return value
if isinstance(value, datetime.timedelta):
return value
try:
parsed = parse_duration(value)
except ValueError:
pass
else:
if parsed is not None:
return parsed
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={'value': value},
)
def get_db_prep_value(self, value, connection, prepared=False):
if connection.features.has_native_duration_field:
return value
if value is None:
return None
return duration_microseconds(value)
def get_db_converters(self, connection):
converters = []
if not connection.features.has_native_duration_field:
converters.append(connection.ops.convert_durationfield_value)
return converters + super().get_db_converters(connection)
def value_to_string(self, obj):
val = self.value_from_object(obj)
return '' if val is None else duration_string(val)
def formfield(self, **kwargs):
return super().formfield(**{
'form_class': forms.DurationField,
**kwargs,
})
class EmailField(CharField):
default_validators = [validators.validate_email]
description = _("Email address")
def __init__(self, *args, **kwargs):
# max_length=254 to be compliant with RFCs 3696 and 5321
kwargs.setdefault('max_length', 254)
super().__init__(*args, **kwargs)
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
# We do not exclude max_length if it matches default as we want to change
# the default in future.
return name, path, args, kwargs
def formfield(self, **kwargs):
# As with CharField, this will cause email validation to be performed
# twice.
return super().formfield(**{
'form_class': forms.EmailField,
**kwargs,
})
class FilePathField(Field):
description = _("File path")
def __init__(self, verbose_name=None, name=None, path='', match=None,
recursive=False, allow_files=True, allow_folders=False, **kwargs):
self.path, self.match, self.recursive = path, match, recursive
self.allow_files, self.allow_folders = allow_files, allow_folders
kwargs.setdefault('max_length', 100)
super().__init__(verbose_name, name, **kwargs)
def check(self, **kwargs):
return [
*super().check(**kwargs),
*self._check_allowing_files_or_folders(**kwargs),
]
def _check_allowing_files_or_folders(self, **kwargs):
if not self.allow_files and not self.allow_folders:
return [
checks.Error(
"FilePathFields must have either 'allow_files' or 'allow_folders' set to True.",
obj=self,
id='fields.E140',
)
]
return []
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if self.path != '':
kwargs['path'] = self.path
if self.match is not None:
kwargs['match'] = self.match
if self.recursive is not False:
kwargs['recursive'] = self.recursive
if self.allow_files is not True:
kwargs['allow_files'] = self.allow_files
if self.allow_folders is not False:
kwargs['allow_folders'] = self.allow_folders
if kwargs.get("max_length") == 100:
del kwargs["max_length"]
return name, path, args, kwargs
def get_prep_value(self, value):
value = super().get_prep_value(value)
if value is None:
return None
return str(value)
def formfield(self, **kwargs):
return super().formfield(**{
'path': self.path() if callable(self.path) else self.path,
'match': self.match,
'recursive': self.recursive,
'form_class': forms.FilePathField,
'allow_files': self.allow_files,
'allow_folders': self.allow_folders,
**kwargs,
})
def get_internal_type(self):
return "FilePathField"
class FloatField(Field):
empty_strings_allowed = False
default_error_messages = {
'invalid': _('“%(value)s” value must be a float.'),
}
description = _("Floating point number")
def get_prep_value(self, value):
value = super().get_prep_value(value)
if value is None:
return None
try:
return float(value)
except (TypeError, ValueError) as e:
raise e.__class__(
"Field '%s' expected a number but got %r." % (self.name, value),
) from e
def get_internal_type(self):
return "FloatField"
def to_python(self, value):
if value is None:
return value
try:
return float(value)
except (TypeError, ValueError):
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={'value': value},
)
def formfield(self, **kwargs):
return super().formfield(**{
'form_class': forms.FloatField,
**kwargs,
})
class IntegerField(Field):
empty_strings_allowed = False
default_error_messages = {
'invalid': _('“%(value)s” value must be an integer.'),
}
description = _("Integer")
def check(self, **kwargs):
return [
*super().check(**kwargs),
*self._check_max_length_warning(),
]
def _check_max_length_warning(self):
if self.max_length is not None:
return [
checks.Warning(
"'max_length' is ignored when used with %s." % self.__class__.__name__,
hint="Remove 'max_length' from field",
obj=self,
id='fields.W122',
)
]
return []
@cached_property
def validators(self):
# These validators can't be added at field initialization time since
# they're based on values retrieved from `connection`.
validators_ = super().validators
internal_type = self.get_internal_type()
min_value, max_value = connection.ops.integer_field_range(internal_type)
if min_value is not None and not any(
(
isinstance(validator, validators.MinValueValidator) and (
validator.limit_value()
if callable(validator.limit_value)
else validator.limit_value
) >= min_value
) for validator in validators_
):
validators_.append(validators.MinValueValidator(min_value))
if max_value is not None and not any(
(
isinstance(validator, validators.MaxValueValidator) and (
validator.limit_value()
if callable(validator.limit_value)
else validator.limit_value
) <= max_value
) for validator in validators_
):
validators_.append(validators.MaxValueValidator(max_value))
return validators_
def get_prep_value(self, value):
value = super().get_prep_value(value)
if value is None:
return None
try:
return int(value)
except (TypeError, ValueError) as e:
raise e.__class__(
"Field '%s' expected a number but got %r." % (self.name, value),
) from e
def get_internal_type(self):
return "IntegerField"
def to_python(self, value):
if value is None:
return value
try:
return int(value)
except (TypeError, ValueError):
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={'value': value},
)
def formfield(self, **kwargs):
return super().formfield(**{
'form_class': forms.IntegerField,
**kwargs,
})
class BigIntegerField(IntegerField):
description = _("Big (8 byte) integer")
MAX_BIGINT = 9223372036854775807
def get_internal_type(self):
return "BigIntegerField"
def formfield(self, **kwargs):
return super().formfield(**{
'min_value': -BigIntegerField.MAX_BIGINT - 1,
'max_value': BigIntegerField.MAX_BIGINT,
**kwargs,
})
class IPAddressField(Field):
empty_strings_allowed = False
description = _("IPv4 address")
system_check_removed_details = {
'msg': (
'IPAddressField has been removed except for support in '
'historical migrations.'
),
'hint': 'Use GenericIPAddressField instead.',
'id': 'fields.E900',
}
def __init__(self, *args, **kwargs):
kwargs['max_length'] = 15
super().__init__(*args, **kwargs)
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
del kwargs['max_length']
return name, path, args, kwargs
def get_prep_value(self, value):
value = super().get_prep_value(value)
if value is None:
return None
return str(value)
def get_internal_type(self):
return "IPAddressField"
class GenericIPAddressField(Field):
empty_strings_allowed = False
description = _("IP address")
default_error_messages = {}
def __init__(self, verbose_name=None, name=None, protocol='both',
unpack_ipv4=False, *args, **kwargs):
self.unpack_ipv4 = unpack_ipv4
self.protocol = protocol
self.default_validators, invalid_error_message = \
validators.ip_address_validators(protocol, unpack_ipv4)
self.default_error_messages['invalid'] = invalid_error_message
kwargs['max_length'] = 39
super().__init__(verbose_name, name, *args, **kwargs)
def check(self, **kwargs):
return [
*super().check(**kwargs),
*self._check_blank_and_null_values(**kwargs),
]
def _check_blank_and_null_values(self, **kwargs):
if not getattr(self, 'null', False) and getattr(self, 'blank', False):
return [
checks.Error(
'GenericIPAddressFields cannot have blank=True if null=False, '
'as blank values are stored as nulls.',
obj=self,
id='fields.E150',
)
]
return []
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if self.unpack_ipv4 is not False:
kwargs['unpack_ipv4'] = self.unpack_ipv4
if self.protocol != "both":
kwargs['protocol'] = self.protocol
if kwargs.get("max_length") == 39:
del kwargs['max_length']
return name, path, args, kwargs
def get_internal_type(self):
return "GenericIPAddressField"
def to_python(self, value):
if value is None:
return None
if not isinstance(value, str):
value = str(value)
value = value.strip()
if ':' in value:
return clean_ipv6_address(value, self.unpack_ipv4, self.error_messages['invalid'])
return value
def get_db_prep_value(self, value, connection, prepared=False):
if not prepared:
value = self.get_prep_value(value)
return connection.ops.adapt_ipaddressfield_value(value)
def get_prep_value(self, value):
value = super().get_prep_value(value)
if value is None:
return None
if value and ':' in value:
try:
return clean_ipv6_address(value, self.unpack_ipv4)
except exceptions.ValidationError:
pass
return str(value)
def formfield(self, **kwargs):
return super().formfield(**{
'protocol': self.protocol,
'form_class': forms.GenericIPAddressField,
**kwargs,
})
class NullBooleanField(BooleanField):
default_error_messages = {
'invalid': _('“%(value)s” value must be either None, True or False.'),
'invalid_nullable': _('“%(value)s” value must be either None, True or False.'),
}
description = _("Boolean (Either True, False or None)")
system_check_deprecated_details = {
'msg': (
'NullBooleanField is deprecated. Support for it (except in '
'historical migrations) will be removed in Django 4.0.'
),
'hint': 'Use BooleanField(null=True) instead.',
'id': 'fields.W903',
}
def __init__(self, *args, **kwargs):
kwargs['null'] = True
kwargs['blank'] = True
super().__init__(*args, **kwargs)
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
del kwargs['null']
del kwargs['blank']
return name, path, args, kwargs
def get_internal_type(self):
return "NullBooleanField"
class PositiveIntegerRelDbTypeMixin:
def rel_db_type(self, connection):
"""
Return the data type that a related field pointing to this field should
use. In most cases, a foreign key pointing to a positive integer
primary key will have an integer column data type but some databases
(e.g. MySQL) have an unsigned integer type. In that case
(related_fields_match_type=True), the primary key should return its
db_type.
"""
if connection.features.related_fields_match_type:
return self.db_type(connection)
else:
return IntegerField().db_type(connection=connection)
class PositiveBigIntegerField(PositiveIntegerRelDbTypeMixin, IntegerField):
description = _('Positive big integer')
def get_internal_type(self):
return 'PositiveBigIntegerField'
def formfield(self, **kwargs):
return super().formfield(**{
'min_value': 0,
**kwargs,
})
class PositiveIntegerField(PositiveIntegerRelDbTypeMixin, IntegerField):
description = _("Positive integer")
def get_internal_type(self):
return "PositiveIntegerField"
def formfield(self, **kwargs):
return super().formfield(**{
'min_value': 0,
**kwargs,
})
class PositiveSmallIntegerField(PositiveIntegerRelDbTypeMixin, IntegerField):
description = _("Positive small integer")
def get_internal_type(self):
return "PositiveSmallIntegerField"
def formfield(self, **kwargs):
return super().formfield(**{
'min_value': 0,
**kwargs,
})
class SlugField(CharField):
default_validators = [validators.validate_slug]
description = _("Slug (up to %(max_length)s)")
def __init__(self, *args, max_length=50, db_index=True, allow_unicode=False, **kwargs):
self.allow_unicode = allow_unicode
if self.allow_unicode:
self.default_validators = [validators.validate_unicode_slug]
super().__init__(*args, max_length=max_length, db_index=db_index, **kwargs)
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if kwargs.get("max_length") == 50:
del kwargs['max_length']
if self.db_index is False:
kwargs['db_index'] = False
else:
del kwargs['db_index']
if self.allow_unicode is not False:
kwargs['allow_unicode'] = self.allow_unicode
return name, path, args, kwargs
def get_internal_type(self):
return "SlugField"
def formfield(self, **kwargs):
return super().formfield(**{
'form_class': forms.SlugField,
'allow_unicode': self.allow_unicode,
**kwargs,
})
class SmallIntegerField(IntegerField):
description = _("Small integer")
def get_internal_type(self):
return "SmallIntegerField"
class TextField(Field):
description = _("Text")
def get_internal_type(self):
return "TextField"
def to_python(self, value):
if isinstance(value, str) or value is None:
return value
return str(value)
def get_prep_value(self, value):
value = super().get_prep_value(value)
return self.to_python(value)
def formfield(self, **kwargs):
# Passing max_length to forms.CharField means that the value's length
# will be validated twice. This is considered acceptable since we want
# the value in the form field (to pass into widget for example).
return super().formfield(**{
'max_length': self.max_length,
**({} if self.choices is not None else {'widget': forms.Textarea}),
**kwargs,
})
class TimeField(DateTimeCheckMixin, Field):
empty_strings_allowed = False
default_error_messages = {
'invalid': _('“%(value)s” value has an invalid format. It must be in '
'HH:MM[:ss[.uuuuuu]] format.'),
'invalid_time': _('“%(value)s” value has the correct format '
'(HH:MM[:ss[.uuuuuu]]) but it is an invalid time.'),
}
description = _("Time")
def __init__(self, verbose_name=None, name=None, auto_now=False,
auto_now_add=False, **kwargs):
self.auto_now, self.auto_now_add = auto_now, auto_now_add
if auto_now or auto_now_add:
kwargs['editable'] = False
kwargs['blank'] = True
super().__init__(verbose_name, name, **kwargs)
def _check_fix_default_value(self):
"""
Warn that using an actual date or datetime value is probably wrong;
it's only evaluated on server startup.
"""
if not self.has_default():
return []
now = timezone.now()
if not timezone.is_naive(now):
now = timezone.make_naive(now, timezone.utc)
value = self.default
if isinstance(value, datetime.datetime):
second_offset = datetime.timedelta(seconds=10)
lower = now - second_offset
upper = now + second_offset
if timezone.is_aware(value):
value = timezone.make_naive(value, timezone.utc)
elif isinstance(value, datetime.time):
second_offset = datetime.timedelta(seconds=10)
lower = now - second_offset
upper = now + second_offset
value = datetime.datetime.combine(now.date(), value)
if timezone.is_aware(value):
value = timezone.make_naive(value, timezone.utc).time()
else:
# No explicit time / datetime value -- no checks necessary
return []
if lower <= value <= upper:
return [
checks.Warning(
'Fixed default value provided.',
hint='It seems you set a fixed date / time / datetime '
'value as default for this field. This may not be '
'what you want. If you want to have the current date '
'as default, use `django.utils.timezone.now`',
obj=self,
id='fields.W161',
)
]
return []
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if self.auto_now is not False:
kwargs["auto_now"] = self.auto_now
if self.auto_now_add is not False:
kwargs["auto_now_add"] = self.auto_now_add
if self.auto_now or self.auto_now_add:
del kwargs['blank']
del kwargs['editable']
return name, path, args, kwargs
def get_internal_type(self):
return "TimeField"
def to_python(self, value):
if value is None:
return None
if isinstance(value, datetime.time):
return value
if isinstance(value, datetime.datetime):
# Not usually a good idea to pass in a datetime here (it loses
# information), but this can be a side-effect of interacting with a
# database backend (e.g. Oracle), so we'll be accommodating.
return value.time()
try:
parsed = parse_time(value)
if parsed is not None:
return parsed
except ValueError:
raise exceptions.ValidationError(
self.error_messages['invalid_time'],
code='invalid_time',
params={'value': value},
)
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={'value': value},
)
def pre_save(self, model_instance, add):
if self.auto_now or (self.auto_now_add and add):
value = datetime.datetime.now().time()
setattr(model_instance, self.attname, value)
return value
else:
return super().pre_save(model_instance, add)
def get_prep_value(self, value):
value = super().get_prep_value(value)
return self.to_python(value)
def get_db_prep_value(self, value, connection, prepared=False):
# Casts times into the format expected by the backend
if not prepared:
value = self.get_prep_value(value)
return connection.ops.adapt_timefield_value(value)
def value_to_string(self, obj):
val = self.value_from_object(obj)
return '' if val is None else val.isoformat()
def formfield(self, **kwargs):
return super().formfield(**{
'form_class': forms.TimeField,
**kwargs,
})
class URLField(CharField):
default_validators = [validators.URLValidator()]
description = _("URL")
def __init__(self, verbose_name=None, name=None, **kwargs):
kwargs.setdefault('max_length', 200)
super().__init__(verbose_name, name, **kwargs)
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if kwargs.get("max_length") == 200:
del kwargs['max_length']
return name, path, args, kwargs
def formfield(self, **kwargs):
# As with CharField, this will cause URL validation to be performed
# twice.
return super().formfield(**{
'form_class': forms.URLField,
**kwargs,
})
class BinaryField(Field):
description = _("Raw binary data")
empty_values = [None, b'']
def __init__(self, *args, **kwargs):
kwargs.setdefault('editable', False)
super().__init__(*args, **kwargs)
if self.max_length is not None:
self.validators.append(validators.MaxLengthValidator(self.max_length))
def check(self, **kwargs):
return [*super().check(**kwargs), *self._check_str_default_value()]
def _check_str_default_value(self):
if self.has_default() and isinstance(self.default, str):
return [
checks.Error(
"BinaryField's default cannot be a string. Use bytes "
"content instead.",
obj=self,
id='fields.E170',
)
]
return []
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if self.editable:
kwargs['editable'] = True
else:
del kwargs['editable']
return name, path, args, kwargs
def get_internal_type(self):
return "BinaryField"
def get_placeholder(self, value, compiler, connection):
return connection.ops.binary_placeholder_sql(value)
def get_default(self):
if self.has_default() and not callable(self.default):
return self.default
default = super().get_default()
if default == '':
return b''
return default
def get_db_prep_value(self, value, connection, prepared=False):
value = super().get_db_prep_value(value, connection, prepared)
if value is not None:
return connection.Database.Binary(value)
return value
def value_to_string(self, obj):
"""Binary data is serialized as base64"""
return b64encode(self.value_from_object(obj)).decode('ascii')
def to_python(self, value):
# If it's a string, it should be base64-encoded data
if isinstance(value, str):
return memoryview(b64decode(value.encode('ascii')))
return value
class UUIDField(Field):
default_error_messages = {
'invalid': _('“%(value)s” is not a valid UUID.'),
}
description = _('Universally unique identifier')
empty_strings_allowed = False
def __init__(self, verbose_name=None, **kwargs):
kwargs['max_length'] = 32
super().__init__(verbose_name, **kwargs)
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
del kwargs['max_length']
return name, path, args, kwargs
def get_internal_type(self):
return "UUIDField"
def get_prep_value(self, value):
value = super().get_prep_value(value)
return self.to_python(value)
def get_db_prep_value(self, value, connection, prepared=False):
if value is None:
return None
if not isinstance(value, uuid.UUID):
value = self.to_python(value)
if connection.features.has_native_uuid_field:
return value
return value.hex
def to_python(self, value):
if value is not None and not isinstance(value, uuid.UUID):
input_form = 'int' if isinstance(value, int) else 'hex'
try:
return uuid.UUID(**{input_form: value})
except (AttributeError, ValueError):
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={'value': value},
)
return value
def formfield(self, **kwargs):
return super().formfield(**{
'form_class': forms.UUIDField,
**kwargs,
})
class AutoFieldMixin:
db_returning = True
def __init__(self, *args, **kwargs):
kwargs['blank'] = True
super().__init__(*args, **kwargs)
def check(self, **kwargs):
return [
*super().check(**kwargs),
*self._check_primary_key(),
]
def _check_primary_key(self):
if not self.primary_key:
return [
checks.Error(
'AutoFields must set primary_key=True.',
obj=self,
id='fields.E100',
),
]
else:
return []
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
del kwargs['blank']
kwargs['primary_key'] = True
return name, path, args, kwargs
def validate(self, value, model_instance):
pass
def get_db_prep_value(self, value, connection, prepared=False):
if not prepared:
value = self.get_prep_value(value)
value = connection.ops.validate_autopk_value(value)
return value
def contribute_to_class(self, cls, name, **kwargs):
assert not cls._meta.auto_field, (
"Model %s can't have more than one auto-generated field."
% cls._meta.label
)
super().contribute_to_class(cls, name, **kwargs)
cls._meta.auto_field = self
def formfield(self, **kwargs):
return None
class AutoFieldMeta(type):
"""
Metaclass to maintain backward inheritance compatibility for AutoField.
It is intended that AutoFieldMixin become public API when it is possible to
create a non-integer automatically-generated field using column defaults
stored in the database.
In many areas Django also relies on using isinstance() to check for an
automatically-generated field as a subclass of AutoField. A new flag needs
to be implemented on Field to be used instead.
When these issues have been addressed, this metaclass could be used to
deprecate inheritance from AutoField and use of isinstance() with AutoField
for detecting automatically-generated fields.
"""
@property
def _subclasses(self):
return (BigAutoField, SmallAutoField)
def __instancecheck__(self, instance):
return isinstance(instance, self._subclasses) or super().__instancecheck__(instance)
def __subclasscheck__(self, subclass):
return subclass in self._subclasses or super().__subclasscheck__(subclass)
class AutoField(AutoFieldMixin, IntegerField, metaclass=AutoFieldMeta):
def get_internal_type(self):
return 'AutoField'
def rel_db_type(self, connection):
return IntegerField().db_type(connection=connection)
class BigAutoField(AutoFieldMixin, BigIntegerField):
def get_internal_type(self):
return 'BigAutoField'
def rel_db_type(self, connection):
return BigIntegerField().db_type(connection=connection)
class SmallAutoField(AutoFieldMixin, SmallIntegerField):
def get_internal_type(self):
return 'SmallAutoField'
def rel_db_type(self, connection):
return SmallIntegerField().db_type(connection=connection)
|
80bc264b44da1df28d5b1b1046f8a19f9569a974317ebba31ccc1d39b7cf8d35 | import functools
import inspect
from functools import partial
from django import forms
from django.apps import apps
from django.conf import SettingsReference, settings
from django.core import checks, exceptions
from django.db import connection, router
from django.db.backends import utils
from django.db.models import Q
from django.db.models.constants import LOOKUP_SEP
from django.db.models.deletion import CASCADE, SET_DEFAULT, SET_NULL
from django.db.models.query_utils import PathInfo
from django.db.models.utils import make_model_tuple
from django.utils.functional import cached_property
from django.utils.translation import gettext_lazy as _
from . import Field
from .mixins import FieldCacheMixin
from .related_descriptors import (
ForeignKeyDeferredAttribute, ForwardManyToOneDescriptor,
ForwardOneToOneDescriptor, ManyToManyDescriptor,
ReverseManyToOneDescriptor, ReverseOneToOneDescriptor,
)
from .related_lookups import (
RelatedExact, RelatedGreaterThan, RelatedGreaterThanOrEqual, RelatedIn,
RelatedIsNull, RelatedLessThan, RelatedLessThanOrEqual,
)
from .reverse_related import (
ForeignObjectRel, ManyToManyRel, ManyToOneRel, OneToOneRel,
)
RECURSIVE_RELATIONSHIP_CONSTANT = 'self'
def resolve_relation(scope_model, relation):
"""
Transform relation into a model or fully-qualified model string of the form
"app_label.ModelName", relative to scope_model.
The relation argument can be:
* RECURSIVE_RELATIONSHIP_CONSTANT, i.e. the string "self", in which case
the model argument will be returned.
* A bare model name without an app_label, in which case scope_model's
app_label will be prepended.
* An "app_label.ModelName" string.
* A model class, which will be returned unchanged.
"""
# Check for recursive relations
if relation == RECURSIVE_RELATIONSHIP_CONSTANT:
relation = scope_model
# Look for an "app.Model" relation
if isinstance(relation, str):
if "." not in relation:
relation = "%s.%s" % (scope_model._meta.app_label, relation)
return relation
def lazy_related_operation(function, model, *related_models, **kwargs):
"""
Schedule `function` to be called once `model` and all `related_models`
have been imported and registered with the app registry. `function` will
be called with the newly-loaded model classes as its positional arguments,
plus any optional keyword arguments.
The `model` argument must be a model class. Each subsequent positional
argument is another model, or a reference to another model - see
`resolve_relation()` for the various forms these may take. Any relative
references will be resolved relative to `model`.
This is a convenience wrapper for `Apps.lazy_model_operation` - the app
registry model used is the one found in `model._meta.apps`.
"""
models = [model] + [resolve_relation(model, rel) for rel in related_models]
model_keys = (make_model_tuple(m) for m in models)
apps = model._meta.apps
return apps.lazy_model_operation(partial(function, **kwargs), *model_keys)
class RelatedField(FieldCacheMixin, Field):
"""Base class that all relational fields inherit from."""
# Field flags
one_to_many = False
one_to_one = False
many_to_many = False
many_to_one = False
@cached_property
def related_model(self):
# Can't cache this property until all the models are loaded.
apps.check_models_ready()
return self.remote_field.model
def check(self, **kwargs):
return [
*super().check(**kwargs),
*self._check_related_name_is_valid(),
*self._check_related_query_name_is_valid(),
*self._check_relation_model_exists(),
*self._check_referencing_to_swapped_model(),
*self._check_clashes(),
]
def _check_related_name_is_valid(self):
import keyword
related_name = self.remote_field.related_name
if related_name is None:
return []
is_valid_id = not keyword.iskeyword(related_name) and related_name.isidentifier()
if not (is_valid_id or related_name.endswith('+')):
return [
checks.Error(
"The name '%s' is invalid related_name for field %s.%s" %
(self.remote_field.related_name, self.model._meta.object_name,
self.name),
hint="Related name must be a valid Python identifier or end with a '+'",
obj=self,
id='fields.E306',
)
]
return []
def _check_related_query_name_is_valid(self):
if self.remote_field.is_hidden():
return []
rel_query_name = self.related_query_name()
errors = []
if rel_query_name.endswith('_'):
errors.append(
checks.Error(
"Reverse query name '%s' must not end with an underscore."
% rel_query_name,
hint=("Add or change a related_name or related_query_name "
"argument for this field."),
obj=self,
id='fields.E308',
)
)
if LOOKUP_SEP in rel_query_name:
errors.append(
checks.Error(
"Reverse query name '%s' must not contain '%s'."
% (rel_query_name, LOOKUP_SEP),
hint=("Add or change a related_name or related_query_name "
"argument for this field."),
obj=self,
id='fields.E309',
)
)
return errors
def _check_relation_model_exists(self):
rel_is_missing = self.remote_field.model not in self.opts.apps.get_models()
rel_is_string = isinstance(self.remote_field.model, str)
model_name = self.remote_field.model if rel_is_string else self.remote_field.model._meta.object_name
if rel_is_missing and (rel_is_string or not self.remote_field.model._meta.swapped):
return [
checks.Error(
"Field defines a relation with model '%s', which is either "
"not installed, or is abstract." % model_name,
obj=self,
id='fields.E300',
)
]
return []
def _check_referencing_to_swapped_model(self):
if (self.remote_field.model not in self.opts.apps.get_models() and
not isinstance(self.remote_field.model, str) and
self.remote_field.model._meta.swapped):
model = "%s.%s" % (
self.remote_field.model._meta.app_label,
self.remote_field.model._meta.object_name
)
return [
checks.Error(
"Field defines a relation with the model '%s', which has "
"been swapped out." % model,
hint="Update the relation to point at 'settings.%s'." % self.remote_field.model._meta.swappable,
obj=self,
id='fields.E301',
)
]
return []
def _check_clashes(self):
"""Check accessor and reverse query name clashes."""
from django.db.models.base import ModelBase
errors = []
opts = self.model._meta
# `f.remote_field.model` may be a string instead of a model. Skip if model name is
# not resolved.
if not isinstance(self.remote_field.model, ModelBase):
return []
# Consider that we are checking field `Model.foreign` and the models
# are:
#
# class Target(models.Model):
# model = models.IntegerField()
# model_set = models.IntegerField()
#
# class Model(models.Model):
# foreign = models.ForeignKey(Target)
# m2m = models.ManyToManyField(Target)
# rel_opts.object_name == "Target"
rel_opts = self.remote_field.model._meta
# If the field doesn't install a backward relation on the target model
# (so `is_hidden` returns True), then there are no clashes to check
# and we can skip these fields.
rel_is_hidden = self.remote_field.is_hidden()
rel_name = self.remote_field.get_accessor_name() # i. e. "model_set"
rel_query_name = self.related_query_name() # i. e. "model"
field_name = "%s.%s" % (opts.object_name, self.name) # i. e. "Model.field"
# Check clashes between accessor or reverse query name of `field`
# and any other field name -- i.e. accessor for Model.foreign is
# model_set and it clashes with Target.model_set.
potential_clashes = rel_opts.fields + rel_opts.many_to_many
for clash_field in potential_clashes:
clash_name = "%s.%s" % (rel_opts.object_name, clash_field.name) # i.e. "Target.model_set"
if not rel_is_hidden and clash_field.name == rel_name:
errors.append(
checks.Error(
"Reverse accessor for '%s' clashes with field name '%s'." % (field_name, clash_name),
hint=("Rename field '%s', or add/change a related_name "
"argument to the definition for field '%s'.") % (clash_name, field_name),
obj=self,
id='fields.E302',
)
)
if clash_field.name == rel_query_name:
errors.append(
checks.Error(
"Reverse query name for '%s' clashes with field name '%s'." % (field_name, clash_name),
hint=("Rename field '%s', or add/change a related_name "
"argument to the definition for field '%s'.") % (clash_name, field_name),
obj=self,
id='fields.E303',
)
)
# Check clashes between accessors/reverse query names of `field` and
# any other field accessor -- i. e. Model.foreign accessor clashes with
# Model.m2m accessor.
potential_clashes = (r for r in rel_opts.related_objects if r.field is not self)
for clash_field in potential_clashes:
clash_name = "%s.%s" % ( # i. e. "Model.m2m"
clash_field.related_model._meta.object_name,
clash_field.field.name)
if not rel_is_hidden and clash_field.get_accessor_name() == rel_name:
errors.append(
checks.Error(
"Reverse accessor for '%s' clashes with reverse accessor for '%s'." % (field_name, clash_name),
hint=("Add or change a related_name argument "
"to the definition for '%s' or '%s'.") % (field_name, clash_name),
obj=self,
id='fields.E304',
)
)
if clash_field.get_accessor_name() == rel_query_name:
errors.append(
checks.Error(
"Reverse query name for '%s' clashes with reverse query name for '%s'."
% (field_name, clash_name),
hint=("Add or change a related_name argument "
"to the definition for '%s' or '%s'.") % (field_name, clash_name),
obj=self,
id='fields.E305',
)
)
return errors
def db_type(self, connection):
# By default related field will not have a column as it relates to
# columns from another table.
return None
def contribute_to_class(self, cls, name, private_only=False, **kwargs):
super().contribute_to_class(cls, name, private_only=private_only, **kwargs)
self.opts = cls._meta
if not cls._meta.abstract:
if self.remote_field.related_name:
related_name = self.remote_field.related_name
else:
related_name = self.opts.default_related_name
if related_name:
related_name = related_name % {
'class': cls.__name__.lower(),
'model_name': cls._meta.model_name.lower(),
'app_label': cls._meta.app_label.lower()
}
self.remote_field.related_name = related_name
if self.remote_field.related_query_name:
related_query_name = self.remote_field.related_query_name % {
'class': cls.__name__.lower(),
'app_label': cls._meta.app_label.lower(),
}
self.remote_field.related_query_name = related_query_name
def resolve_related_class(model, related, field):
field.remote_field.model = related
field.do_related_class(related, model)
lazy_related_operation(resolve_related_class, cls, self.remote_field.model, field=self)
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if self.remote_field.limit_choices_to:
kwargs['limit_choices_to'] = self.remote_field.limit_choices_to
if self.remote_field.related_name is not None:
kwargs['related_name'] = self.remote_field.related_name
if self.remote_field.related_query_name is not None:
kwargs['related_query_name'] = self.remote_field.related_query_name
return name, path, args, kwargs
def get_forward_related_filter(self, obj):
"""
Return the keyword arguments that when supplied to
self.model.object.filter(), would select all instances related through
this field to the remote obj. This is used to build the querysets
returned by related descriptors. obj is an instance of
self.related_field.model.
"""
return {
'%s__%s' % (self.name, rh_field.name): getattr(obj, rh_field.attname)
for _, rh_field in self.related_fields
}
def get_reverse_related_filter(self, obj):
"""
Complement to get_forward_related_filter(). Return the keyword
arguments that when passed to self.related_field.model.object.filter()
select all instances of self.related_field.model related through
this field to obj. obj is an instance of self.model.
"""
base_filter = {
rh_field.attname: getattr(obj, lh_field.attname)
for lh_field, rh_field in self.related_fields
}
descriptor_filter = self.get_extra_descriptor_filter(obj)
base_q = Q(**base_filter)
if isinstance(descriptor_filter, dict):
return base_q & Q(**descriptor_filter)
elif descriptor_filter:
return base_q & descriptor_filter
return base_q
@property
def swappable_setting(self):
"""
Get the setting that this is powered from for swapping, or None
if it's not swapped in / marked with swappable=False.
"""
if self.swappable:
# Work out string form of "to"
if isinstance(self.remote_field.model, str):
to_string = self.remote_field.model
else:
to_string = self.remote_field.model._meta.label
return apps.get_swappable_settings_name(to_string)
return None
def set_attributes_from_rel(self):
self.name = (
self.name or
(self.remote_field.model._meta.model_name + '_' + self.remote_field.model._meta.pk.name)
)
if self.verbose_name is None:
self.verbose_name = self.remote_field.model._meta.verbose_name
self.remote_field.set_field_name()
def do_related_class(self, other, cls):
self.set_attributes_from_rel()
self.contribute_to_related_class(other, self.remote_field)
def get_limit_choices_to(self):
"""
Return ``limit_choices_to`` for this model field.
If it is a callable, it will be invoked and the result will be
returned.
"""
if callable(self.remote_field.limit_choices_to):
return self.remote_field.limit_choices_to()
return self.remote_field.limit_choices_to
def formfield(self, **kwargs):
"""
Pass ``limit_choices_to`` to the field being constructed.
Only passes it if there is a type that supports related fields.
This is a similar strategy used to pass the ``queryset`` to the field
being constructed.
"""
defaults = {}
if hasattr(self.remote_field, 'get_related_field'):
# If this is a callable, do not invoke it here. Just pass
# it in the defaults for when the form class will later be
# instantiated.
limit_choices_to = self.remote_field.limit_choices_to
defaults.update({
'limit_choices_to': limit_choices_to,
})
defaults.update(kwargs)
return super().formfield(**defaults)
def related_query_name(self):
"""
Define the name that can be used to identify this related object in a
table-spanning query.
"""
return self.remote_field.related_query_name or self.remote_field.related_name or self.opts.model_name
@property
def target_field(self):
"""
When filtering against this relation, return the field on the remote
model against which the filtering should happen.
"""
target_fields = self.get_path_info()[-1].target_fields
if len(target_fields) > 1:
raise exceptions.FieldError(
"The relation has multiple target fields, but only single target field was asked for")
return target_fields[0]
def get_cache_name(self):
return self.name
class ForeignObject(RelatedField):
"""
Abstraction of the ForeignKey relation to support multi-column relations.
"""
# Field flags
many_to_many = False
many_to_one = True
one_to_many = False
one_to_one = False
requires_unique_target = True
related_accessor_class = ReverseManyToOneDescriptor
forward_related_accessor_class = ForwardManyToOneDescriptor
rel_class = ForeignObjectRel
def __init__(self, to, on_delete, from_fields, to_fields, rel=None, related_name=None,
related_query_name=None, limit_choices_to=None, parent_link=False,
swappable=True, **kwargs):
if rel is None:
rel = self.rel_class(
self, to,
related_name=related_name,
related_query_name=related_query_name,
limit_choices_to=limit_choices_to,
parent_link=parent_link,
on_delete=on_delete,
)
super().__init__(rel=rel, **kwargs)
self.from_fields = from_fields
self.to_fields = to_fields
self.swappable = swappable
def check(self, **kwargs):
return [
*super().check(**kwargs),
*self._check_to_fields_exist(),
*self._check_unique_target(),
]
def _check_to_fields_exist(self):
# Skip nonexistent models.
if isinstance(self.remote_field.model, str):
return []
errors = []
for to_field in self.to_fields:
if to_field:
try:
self.remote_field.model._meta.get_field(to_field)
except exceptions.FieldDoesNotExist:
errors.append(
checks.Error(
"The to_field '%s' doesn't exist on the related "
"model '%s'."
% (to_field, self.remote_field.model._meta.label),
obj=self,
id='fields.E312',
)
)
return errors
def _check_unique_target(self):
rel_is_string = isinstance(self.remote_field.model, str)
if rel_is_string or not self.requires_unique_target:
return []
try:
self.foreign_related_fields
except exceptions.FieldDoesNotExist:
return []
if not self.foreign_related_fields:
return []
unique_foreign_fields = {
frozenset([f.name])
for f in self.remote_field.model._meta.get_fields()
if getattr(f, 'unique', False)
}
unique_foreign_fields.update({
frozenset(ut)
for ut in self.remote_field.model._meta.unique_together
})
unique_foreign_fields.update({
frozenset(uc.fields)
for uc in self.remote_field.model._meta.total_unique_constraints
})
foreign_fields = {f.name for f in self.foreign_related_fields}
has_unique_constraint = any(u <= foreign_fields for u in unique_foreign_fields)
if not has_unique_constraint and len(self.foreign_related_fields) > 1:
field_combination = ', '.join(
"'%s'" % rel_field.name for rel_field in self.foreign_related_fields
)
model_name = self.remote_field.model.__name__
return [
checks.Error(
"No subset of the fields %s on model '%s' is unique."
% (field_combination, model_name),
hint=(
'Mark a single field as unique=True or add a set of '
'fields to a unique constraint (via unique_together '
'or a UniqueConstraint (without condition) in the '
'model Meta.constraints).'
),
obj=self,
id='fields.E310',
)
]
elif not has_unique_constraint:
field_name = self.foreign_related_fields[0].name
model_name = self.remote_field.model.__name__
return [
checks.Error(
"'%s.%s' must be unique because it is referenced by "
"a foreign key." % (model_name, field_name),
hint=(
'Add unique=True to this field or add a '
'UniqueConstraint (without condition) in the model '
'Meta.constraints.'
),
obj=self,
id='fields.E311',
)
]
else:
return []
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
kwargs['on_delete'] = self.remote_field.on_delete
kwargs['from_fields'] = self.from_fields
kwargs['to_fields'] = self.to_fields
if self.remote_field.parent_link:
kwargs['parent_link'] = self.remote_field.parent_link
if isinstance(self.remote_field.model, str):
kwargs['to'] = self.remote_field.model.lower()
else:
kwargs['to'] = self.remote_field.model._meta.label_lower
# If swappable is True, then see if we're actually pointing to the target
# of a swap.
swappable_setting = self.swappable_setting
if swappable_setting is not None:
# If it's already a settings reference, error
if hasattr(kwargs['to'], "setting_name"):
if kwargs['to'].setting_name != swappable_setting:
raise ValueError(
"Cannot deconstruct a ForeignKey pointing to a model "
"that is swapped in place of more than one model (%s and %s)"
% (kwargs['to'].setting_name, swappable_setting)
)
# Set it
kwargs['to'] = SettingsReference(
kwargs['to'],
swappable_setting,
)
return name, path, args, kwargs
def resolve_related_fields(self):
if not self.from_fields or len(self.from_fields) != len(self.to_fields):
raise ValueError('Foreign Object from and to fields must be the same non-zero length')
if isinstance(self.remote_field.model, str):
raise ValueError('Related model %r cannot be resolved' % self.remote_field.model)
related_fields = []
for index in range(len(self.from_fields)):
from_field_name = self.from_fields[index]
to_field_name = self.to_fields[index]
from_field = (
self
if from_field_name == RECURSIVE_RELATIONSHIP_CONSTANT
else self.opts.get_field(from_field_name)
)
to_field = (self.remote_field.model._meta.pk if to_field_name is None
else self.remote_field.model._meta.get_field(to_field_name))
related_fields.append((from_field, to_field))
return related_fields
@cached_property
def related_fields(self):
return self.resolve_related_fields()
@cached_property
def reverse_related_fields(self):
return [(rhs_field, lhs_field) for lhs_field, rhs_field in self.related_fields]
@cached_property
def local_related_fields(self):
return tuple(lhs_field for lhs_field, rhs_field in self.related_fields)
@cached_property
def foreign_related_fields(self):
return tuple(rhs_field for lhs_field, rhs_field in self.related_fields if rhs_field)
def get_local_related_value(self, instance):
return self.get_instance_value_for_fields(instance, self.local_related_fields)
def get_foreign_related_value(self, instance):
return self.get_instance_value_for_fields(instance, self.foreign_related_fields)
@staticmethod
def get_instance_value_for_fields(instance, fields):
ret = []
opts = instance._meta
for field in fields:
# Gotcha: in some cases (like fixture loading) a model can have
# different values in parent_ptr_id and parent's id. So, use
# instance.pk (that is, parent_ptr_id) when asked for instance.id.
if field.primary_key:
possible_parent_link = opts.get_ancestor_link(field.model)
if (not possible_parent_link or
possible_parent_link.primary_key or
possible_parent_link.model._meta.abstract):
ret.append(instance.pk)
continue
ret.append(getattr(instance, field.attname))
return tuple(ret)
def get_attname_column(self):
attname, column = super().get_attname_column()
return attname, None
def get_joining_columns(self, reverse_join=False):
source = self.reverse_related_fields if reverse_join else self.related_fields
return tuple((lhs_field.column, rhs_field.column) for lhs_field, rhs_field in source)
def get_reverse_joining_columns(self):
return self.get_joining_columns(reverse_join=True)
def get_extra_descriptor_filter(self, instance):
"""
Return an extra filter condition for related object fetching when
user does 'instance.fieldname', that is the extra filter is used in
the descriptor of the field.
The filter should be either a dict usable in .filter(**kwargs) call or
a Q-object. The condition will be ANDed together with the relation's
joining columns.
A parallel method is get_extra_restriction() which is used in
JOIN and subquery conditions.
"""
return {}
def get_extra_restriction(self, where_class, alias, related_alias):
"""
Return a pair condition used for joining and subquery pushdown. The
condition is something that responds to as_sql(compiler, connection)
method.
Note that currently referring both the 'alias' and 'related_alias'
will not work in some conditions, like subquery pushdown.
A parallel method is get_extra_descriptor_filter() which is used in
instance.fieldname related object fetching.
"""
return None
def get_path_info(self, filtered_relation=None):
"""Get path from this field to the related model."""
opts = self.remote_field.model._meta
from_opts = self.model._meta
return [PathInfo(
from_opts=from_opts,
to_opts=opts,
target_fields=self.foreign_related_fields,
join_field=self,
m2m=False,
direct=True,
filtered_relation=filtered_relation,
)]
def get_reverse_path_info(self, filtered_relation=None):
"""Get path from the related model to this field's model."""
opts = self.model._meta
from_opts = self.remote_field.model._meta
return [PathInfo(
from_opts=from_opts,
to_opts=opts,
target_fields=(opts.pk,),
join_field=self.remote_field,
m2m=not self.unique,
direct=False,
filtered_relation=filtered_relation,
)]
@classmethod
@functools.lru_cache(maxsize=None)
def get_lookups(cls):
bases = inspect.getmro(cls)
bases = bases[:bases.index(ForeignObject) + 1]
class_lookups = [parent.__dict__.get('class_lookups', {}) for parent in bases]
return cls.merge_dicts(class_lookups)
def contribute_to_class(self, cls, name, private_only=False, **kwargs):
super().contribute_to_class(cls, name, private_only=private_only, **kwargs)
setattr(cls, self.name, self.forward_related_accessor_class(self))
def contribute_to_related_class(self, cls, related):
# Internal FK's - i.e., those with a related name ending with '+' -
# and swapped models don't get a related descriptor.
if not self.remote_field.is_hidden() and not related.related_model._meta.swapped:
setattr(cls._meta.concrete_model, related.get_accessor_name(), self.related_accessor_class(related))
# While 'limit_choices_to' might be a callable, simply pass
# it along for later - this is too early because it's still
# model load time.
if self.remote_field.limit_choices_to:
cls._meta.related_fkey_lookups.append(self.remote_field.limit_choices_to)
ForeignObject.register_lookup(RelatedIn)
ForeignObject.register_lookup(RelatedExact)
ForeignObject.register_lookup(RelatedLessThan)
ForeignObject.register_lookup(RelatedGreaterThan)
ForeignObject.register_lookup(RelatedGreaterThanOrEqual)
ForeignObject.register_lookup(RelatedLessThanOrEqual)
ForeignObject.register_lookup(RelatedIsNull)
class ForeignKey(ForeignObject):
"""
Provide a many-to-one relation by adding a column to the local model
to hold the remote value.
By default ForeignKey will target the pk of the remote model but this
behavior can be changed by using the ``to_field`` argument.
"""
descriptor_class = ForeignKeyDeferredAttribute
# Field flags
many_to_many = False
many_to_one = True
one_to_many = False
one_to_one = False
rel_class = ManyToOneRel
empty_strings_allowed = False
default_error_messages = {
'invalid': _('%(model)s instance with %(field)s %(value)r does not exist.')
}
description = _("Foreign Key (type determined by related field)")
def __init__(self, to, on_delete, related_name=None, related_query_name=None,
limit_choices_to=None, parent_link=False, to_field=None,
db_constraint=True, **kwargs):
try:
to._meta.model_name
except AttributeError:
assert isinstance(to, str), (
"%s(%r) is invalid. First parameter to ForeignKey must be "
"either a model, a model name, or the string %r" % (
self.__class__.__name__, to,
RECURSIVE_RELATIONSHIP_CONSTANT,
)
)
else:
# For backwards compatibility purposes, we need to *try* and set
# the to_field during FK construction. It won't be guaranteed to
# be correct until contribute_to_class is called. Refs #12190.
to_field = to_field or (to._meta.pk and to._meta.pk.name)
if not callable(on_delete):
raise TypeError('on_delete must be callable.')
kwargs['rel'] = self.rel_class(
self, to, to_field,
related_name=related_name,
related_query_name=related_query_name,
limit_choices_to=limit_choices_to,
parent_link=parent_link,
on_delete=on_delete,
)
kwargs.setdefault('db_index', True)
super().__init__(
to,
on_delete,
from_fields=[RECURSIVE_RELATIONSHIP_CONSTANT],
to_fields=[to_field],
**kwargs,
)
self.db_constraint = db_constraint
def check(self, **kwargs):
return [
*super().check(**kwargs),
*self._check_on_delete(),
*self._check_unique(),
]
def _check_on_delete(self):
on_delete = getattr(self.remote_field, 'on_delete', None)
if on_delete == SET_NULL and not self.null:
return [
checks.Error(
'Field specifies on_delete=SET_NULL, but cannot be null.',
hint='Set null=True argument on the field, or change the on_delete rule.',
obj=self,
id='fields.E320',
)
]
elif on_delete == SET_DEFAULT and not self.has_default():
return [
checks.Error(
'Field specifies on_delete=SET_DEFAULT, but has no default value.',
hint='Set a default value, or change the on_delete rule.',
obj=self,
id='fields.E321',
)
]
else:
return []
def _check_unique(self, **kwargs):
return [
checks.Warning(
'Setting unique=True on a ForeignKey has the same effect as using a OneToOneField.',
hint='ForeignKey(unique=True) is usually better served by a OneToOneField.',
obj=self,
id='fields.W342',
)
] if self.unique else []
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
del kwargs['to_fields']
del kwargs['from_fields']
# Handle the simpler arguments
if self.db_index:
del kwargs['db_index']
else:
kwargs['db_index'] = False
if self.db_constraint is not True:
kwargs['db_constraint'] = self.db_constraint
# Rel needs more work.
to_meta = getattr(self.remote_field.model, "_meta", None)
if self.remote_field.field_name and (
not to_meta or (to_meta.pk and self.remote_field.field_name != to_meta.pk.name)):
kwargs['to_field'] = self.remote_field.field_name
return name, path, args, kwargs
def to_python(self, value):
return self.target_field.to_python(value)
@property
def target_field(self):
return self.foreign_related_fields[0]
def get_reverse_path_info(self, filtered_relation=None):
"""Get path from the related model to this field's model."""
opts = self.model._meta
from_opts = self.remote_field.model._meta
return [PathInfo(
from_opts=from_opts,
to_opts=opts,
target_fields=(opts.pk,),
join_field=self.remote_field,
m2m=not self.unique,
direct=False,
filtered_relation=filtered_relation,
)]
def validate(self, value, model_instance):
if self.remote_field.parent_link:
return
super().validate(value, model_instance)
if value is None:
return
using = router.db_for_read(self.remote_field.model, instance=model_instance)
qs = self.remote_field.model._default_manager.using(using).filter(
**{self.remote_field.field_name: value}
)
qs = qs.complex_filter(self.get_limit_choices_to())
if not qs.exists():
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={
'model': self.remote_field.model._meta.verbose_name, 'pk': value,
'field': self.remote_field.field_name, 'value': value,
}, # 'pk' is included for backwards compatibility
)
def resolve_related_fields(self):
related_fields = super().resolve_related_fields()
for from_field, to_field in related_fields:
if to_field and to_field.model != self.remote_field.model._meta.concrete_model:
raise exceptions.FieldError(
"'%s.%s' refers to field '%s' which is not local to model "
"'%s'." % (
self.model._meta.label,
self.name,
to_field.name,
self.remote_field.model._meta.concrete_model._meta.label,
)
)
return related_fields
def get_attname(self):
return '%s_id' % self.name
def get_attname_column(self):
attname = self.get_attname()
column = self.db_column or attname
return attname, column
def get_default(self):
"""Return the to_field if the default value is an object."""
field_default = super().get_default()
if isinstance(field_default, self.remote_field.model):
return getattr(field_default, self.target_field.attname)
return field_default
def get_db_prep_save(self, value, connection):
if value is None or (value == '' and
(not self.target_field.empty_strings_allowed or
connection.features.interprets_empty_strings_as_nulls)):
return None
else:
return self.target_field.get_db_prep_save(value, connection=connection)
def get_db_prep_value(self, value, connection, prepared=False):
return self.target_field.get_db_prep_value(value, connection, prepared)
def get_prep_value(self, value):
return self.target_field.get_prep_value(value)
def contribute_to_related_class(self, cls, related):
super().contribute_to_related_class(cls, related)
if self.remote_field.field_name is None:
self.remote_field.field_name = cls._meta.pk.name
def formfield(self, *, using=None, **kwargs):
if isinstance(self.remote_field.model, str):
raise ValueError("Cannot create form field for %r yet, because "
"its related model %r has not been loaded yet" %
(self.name, self.remote_field.model))
return super().formfield(**{
'form_class': forms.ModelChoiceField,
'queryset': self.remote_field.model._default_manager.using(using),
'to_field_name': self.remote_field.field_name,
**kwargs,
'blank': self.blank,
})
def db_check(self, connection):
return []
def db_type(self, connection):
return self.target_field.rel_db_type(connection=connection)
def db_parameters(self, connection):
return {"type": self.db_type(connection), "check": self.db_check(connection)}
def convert_empty_strings(self, value, expression, connection):
if (not value) and isinstance(value, str):
return None
return value
def get_db_converters(self, connection):
converters = super().get_db_converters(connection)
if connection.features.interprets_empty_strings_as_nulls:
converters += [self.convert_empty_strings]
return converters
def get_col(self, alias, output_field=None):
if output_field is None:
output_field = self.target_field
while isinstance(output_field, ForeignKey):
output_field = output_field.target_field
if output_field is self:
raise ValueError('Cannot resolve output_field.')
return super().get_col(alias, output_field)
class OneToOneField(ForeignKey):
"""
A OneToOneField is essentially the same as a ForeignKey, with the exception
that it always carries a "unique" constraint with it and the reverse
relation always returns the object pointed to (since there will only ever
be one), rather than returning a list.
"""
# Field flags
many_to_many = False
many_to_one = False
one_to_many = False
one_to_one = True
related_accessor_class = ReverseOneToOneDescriptor
forward_related_accessor_class = ForwardOneToOneDescriptor
rel_class = OneToOneRel
description = _("One-to-one relationship")
def __init__(self, to, on_delete, to_field=None, **kwargs):
kwargs['unique'] = True
super().__init__(to, on_delete, to_field=to_field, **kwargs)
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if "unique" in kwargs:
del kwargs['unique']
return name, path, args, kwargs
def formfield(self, **kwargs):
if self.remote_field.parent_link:
return None
return super().formfield(**kwargs)
def save_form_data(self, instance, data):
if isinstance(data, self.remote_field.model):
setattr(instance, self.name, data)
else:
setattr(instance, self.attname, data)
# Remote field object must be cleared otherwise Model.save()
# will reassign attname using the related object pk.
if data is None:
setattr(instance, self.name, data)
def _check_unique(self, **kwargs):
# Override ForeignKey since check isn't applicable here.
return []
def create_many_to_many_intermediary_model(field, klass):
from django.db import models
def set_managed(model, related, through):
through._meta.managed = model._meta.managed or related._meta.managed
to_model = resolve_relation(klass, field.remote_field.model)
name = '%s_%s' % (klass._meta.object_name, field.name)
lazy_related_operation(set_managed, klass, to_model, name)
to = make_model_tuple(to_model)[1]
from_ = klass._meta.model_name
if to == from_:
to = 'to_%s' % to
from_ = 'from_%s' % from_
meta = type('Meta', (), {
'db_table': field._get_m2m_db_table(klass._meta),
'auto_created': klass,
'app_label': klass._meta.app_label,
'db_tablespace': klass._meta.db_tablespace,
'unique_together': (from_, to),
'verbose_name': _('%(from)s-%(to)s relationship') % {'from': from_, 'to': to},
'verbose_name_plural': _('%(from)s-%(to)s relationships') % {'from': from_, 'to': to},
'apps': field.model._meta.apps,
})
# Construct and return the new class.
return type(name, (models.Model,), {
'Meta': meta,
'__module__': klass.__module__,
from_: models.ForeignKey(
klass,
related_name='%s+' % name,
db_tablespace=field.db_tablespace,
db_constraint=field.remote_field.db_constraint,
on_delete=CASCADE,
),
to: models.ForeignKey(
to_model,
related_name='%s+' % name,
db_tablespace=field.db_tablespace,
db_constraint=field.remote_field.db_constraint,
on_delete=CASCADE,
)
})
class ManyToManyField(RelatedField):
"""
Provide a many-to-many relation by using an intermediary model that
holds two ForeignKey fields pointed at the two sides of the relation.
Unless a ``through`` model was provided, ManyToManyField will use the
create_many_to_many_intermediary_model factory to automatically generate
the intermediary model.
"""
# Field flags
many_to_many = True
many_to_one = False
one_to_many = False
one_to_one = False
rel_class = ManyToManyRel
description = _("Many-to-many relationship")
def __init__(self, to, related_name=None, related_query_name=None,
limit_choices_to=None, symmetrical=None, through=None,
through_fields=None, db_constraint=True, db_table=None,
swappable=True, **kwargs):
try:
to._meta
except AttributeError:
assert isinstance(to, str), (
"%s(%r) is invalid. First parameter to ManyToManyField must be "
"either a model, a model name, or the string %r" %
(self.__class__.__name__, to, RECURSIVE_RELATIONSHIP_CONSTANT)
)
if symmetrical is None:
symmetrical = (to == RECURSIVE_RELATIONSHIP_CONSTANT)
if through is not None:
assert db_table is None, (
"Cannot specify a db_table if an intermediary model is used."
)
kwargs['rel'] = self.rel_class(
self, to,
related_name=related_name,
related_query_name=related_query_name,
limit_choices_to=limit_choices_to,
symmetrical=symmetrical,
through=through,
through_fields=through_fields,
db_constraint=db_constraint,
)
self.has_null_arg = 'null' in kwargs
super().__init__(**kwargs)
self.db_table = db_table
self.swappable = swappable
def check(self, **kwargs):
return [
*super().check(**kwargs),
*self._check_unique(**kwargs),
*self._check_relationship_model(**kwargs),
*self._check_ignored_options(**kwargs),
*self._check_table_uniqueness(**kwargs),
]
def _check_unique(self, **kwargs):
if self.unique:
return [
checks.Error(
'ManyToManyFields cannot be unique.',
obj=self,
id='fields.E330',
)
]
return []
def _check_ignored_options(self, **kwargs):
warnings = []
if self.has_null_arg:
warnings.append(
checks.Warning(
'null has no effect on ManyToManyField.',
obj=self,
id='fields.W340',
)
)
if self._validators:
warnings.append(
checks.Warning(
'ManyToManyField does not support validators.',
obj=self,
id='fields.W341',
)
)
if (self.remote_field.limit_choices_to and self.remote_field.through and
not self.remote_field.through._meta.auto_created):
warnings.append(
checks.Warning(
'limit_choices_to has no effect on ManyToManyField '
'with a through model.',
obj=self,
id='fields.W343',
)
)
return warnings
def _check_relationship_model(self, from_model=None, **kwargs):
if hasattr(self.remote_field.through, '_meta'):
qualified_model_name = "%s.%s" % (
self.remote_field.through._meta.app_label, self.remote_field.through.__name__)
else:
qualified_model_name = self.remote_field.through
errors = []
if self.remote_field.through not in self.opts.apps.get_models(include_auto_created=True):
# The relationship model is not installed.
errors.append(
checks.Error(
"Field specifies a many-to-many relation through model "
"'%s', which has not been installed." % qualified_model_name,
obj=self,
id='fields.E331',
)
)
else:
assert from_model is not None, (
"ManyToManyField with intermediate "
"tables cannot be checked if you don't pass the model "
"where the field is attached to."
)
# Set some useful local variables
to_model = resolve_relation(from_model, self.remote_field.model)
from_model_name = from_model._meta.object_name
if isinstance(to_model, str):
to_model_name = to_model
else:
to_model_name = to_model._meta.object_name
relationship_model_name = self.remote_field.through._meta.object_name
self_referential = from_model == to_model
# Count foreign keys in intermediate model
if self_referential:
seen_self = sum(
from_model == getattr(field.remote_field, 'model', None)
for field in self.remote_field.through._meta.fields
)
if seen_self > 2 and not self.remote_field.through_fields:
errors.append(
checks.Error(
"The model is used as an intermediate model by "
"'%s', but it has more than two foreign keys "
"to '%s', which is ambiguous. You must specify "
"which two foreign keys Django should use via the "
"through_fields keyword argument." % (self, from_model_name),
hint="Use through_fields to specify which two foreign keys Django should use.",
obj=self.remote_field.through,
id='fields.E333',
)
)
else:
# Count foreign keys in relationship model
seen_from = sum(
from_model == getattr(field.remote_field, 'model', None)
for field in self.remote_field.through._meta.fields
)
seen_to = sum(
to_model == getattr(field.remote_field, 'model', None)
for field in self.remote_field.through._meta.fields
)
if seen_from > 1 and not self.remote_field.through_fields:
errors.append(
checks.Error(
("The model is used as an intermediate model by "
"'%s', but it has more than one foreign key "
"from '%s', which is ambiguous. You must specify "
"which foreign key Django should use via the "
"through_fields keyword argument.") % (self, from_model_name),
hint=(
'If you want to create a recursive relationship, '
'use ManyToManyField("%s", through="%s").'
) % (
RECURSIVE_RELATIONSHIP_CONSTANT,
relationship_model_name,
),
obj=self,
id='fields.E334',
)
)
if seen_to > 1 and not self.remote_field.through_fields:
errors.append(
checks.Error(
"The model is used as an intermediate model by "
"'%s', but it has more than one foreign key "
"to '%s', which is ambiguous. You must specify "
"which foreign key Django should use via the "
"through_fields keyword argument." % (self, to_model_name),
hint=(
'If you want to create a recursive relationship, '
'use ManyToManyField("%s", through="%s").'
) % (
RECURSIVE_RELATIONSHIP_CONSTANT,
relationship_model_name,
),
obj=self,
id='fields.E335',
)
)
if seen_from == 0 or seen_to == 0:
errors.append(
checks.Error(
"The model is used as an intermediate model by "
"'%s', but it does not have a foreign key to '%s' or '%s'." % (
self, from_model_name, to_model_name
),
obj=self.remote_field.through,
id='fields.E336',
)
)
# Validate `through_fields`.
if self.remote_field.through_fields is not None:
# Validate that we're given an iterable of at least two items
# and that none of them is "falsy".
if not (len(self.remote_field.through_fields) >= 2 and
self.remote_field.through_fields[0] and self.remote_field.through_fields[1]):
errors.append(
checks.Error(
"Field specifies 'through_fields' but does not provide "
"the names of the two link fields that should be used "
"for the relation through model '%s'." % qualified_model_name,
hint="Make sure you specify 'through_fields' as through_fields=('field1', 'field2')",
obj=self,
id='fields.E337',
)
)
# Validate the given through fields -- they should be actual
# fields on the through model, and also be foreign keys to the
# expected models.
else:
assert from_model is not None, (
"ManyToManyField with intermediate "
"tables cannot be checked if you don't pass the model "
"where the field is attached to."
)
source, through, target = from_model, self.remote_field.through, self.remote_field.model
source_field_name, target_field_name = self.remote_field.through_fields[:2]
for field_name, related_model in ((source_field_name, source),
(target_field_name, target)):
possible_field_names = []
for f in through._meta.fields:
if hasattr(f, 'remote_field') and getattr(f.remote_field, 'model', None) == related_model:
possible_field_names.append(f.name)
if possible_field_names:
hint = "Did you mean one of the following foreign keys to '%s': %s?" % (
related_model._meta.object_name,
', '.join(possible_field_names),
)
else:
hint = None
try:
field = through._meta.get_field(field_name)
except exceptions.FieldDoesNotExist:
errors.append(
checks.Error(
"The intermediary model '%s' has no field '%s'."
% (qualified_model_name, field_name),
hint=hint,
obj=self,
id='fields.E338',
)
)
else:
if not (hasattr(field, 'remote_field') and
getattr(field.remote_field, 'model', None) == related_model):
errors.append(
checks.Error(
"'%s.%s' is not a foreign key to '%s'." % (
through._meta.object_name, field_name,
related_model._meta.object_name,
),
hint=hint,
obj=self,
id='fields.E339',
)
)
return errors
def _check_table_uniqueness(self, **kwargs):
if isinstance(self.remote_field.through, str) or not self.remote_field.through._meta.managed:
return []
registered_tables = {
model._meta.db_table: model
for model in self.opts.apps.get_models(include_auto_created=True)
if model != self.remote_field.through and model._meta.managed
}
m2m_db_table = self.m2m_db_table()
model = registered_tables.get(m2m_db_table)
# The second condition allows multiple m2m relations on a model if
# some point to a through model that proxies another through model.
if model and model._meta.concrete_model != self.remote_field.through._meta.concrete_model:
if model._meta.auto_created:
def _get_field_name(model):
for field in model._meta.auto_created._meta.many_to_many:
if field.remote_field.through is model:
return field.name
opts = model._meta.auto_created._meta
clashing_obj = '%s.%s' % (opts.label, _get_field_name(model))
else:
clashing_obj = model._meta.label
if settings.DATABASE_ROUTERS:
error_class, error_id = checks.Warning, 'fields.W344'
error_hint = (
'You have configured settings.DATABASE_ROUTERS. Verify '
'that the table of %r is correctly routed to a separate '
'database.' % clashing_obj
)
else:
error_class, error_id = checks.Error, 'fields.E340'
error_hint = None
return [
error_class(
"The field's intermediary table '%s' clashes with the "
"table name of '%s'." % (m2m_db_table, clashing_obj),
obj=self,
hint=error_hint,
id=error_id,
)
]
return []
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
# Handle the simpler arguments.
if self.db_table is not None:
kwargs['db_table'] = self.db_table
if self.remote_field.db_constraint is not True:
kwargs['db_constraint'] = self.remote_field.db_constraint
# Rel needs more work.
if isinstance(self.remote_field.model, str):
kwargs['to'] = self.remote_field.model
else:
kwargs['to'] = "%s.%s" % (
self.remote_field.model._meta.app_label,
self.remote_field.model._meta.object_name,
)
if getattr(self.remote_field, 'through', None) is not None:
if isinstance(self.remote_field.through, str):
kwargs['through'] = self.remote_field.through
elif not self.remote_field.through._meta.auto_created:
kwargs['through'] = "%s.%s" % (
self.remote_field.through._meta.app_label,
self.remote_field.through._meta.object_name,
)
# If swappable is True, then see if we're actually pointing to the target
# of a swap.
swappable_setting = self.swappable_setting
if swappable_setting is not None:
# If it's already a settings reference, error.
if hasattr(kwargs['to'], "setting_name"):
if kwargs['to'].setting_name != swappable_setting:
raise ValueError(
"Cannot deconstruct a ManyToManyField pointing to a "
"model that is swapped in place of more than one model "
"(%s and %s)" % (kwargs['to'].setting_name, swappable_setting)
)
kwargs['to'] = SettingsReference(
kwargs['to'],
swappable_setting,
)
return name, path, args, kwargs
def _get_path_info(self, direct=False, filtered_relation=None):
"""Called by both direct and indirect m2m traversal."""
int_model = self.remote_field.through
linkfield1 = int_model._meta.get_field(self.m2m_field_name())
linkfield2 = int_model._meta.get_field(self.m2m_reverse_field_name())
if direct:
join1infos = linkfield1.get_reverse_path_info()
join2infos = linkfield2.get_path_info(filtered_relation)
else:
join1infos = linkfield2.get_reverse_path_info()
join2infos = linkfield1.get_path_info(filtered_relation)
# Get join infos between the last model of join 1 and the first model
# of join 2. Assume the only reason these may differ is due to model
# inheritance.
join1_final = join1infos[-1].to_opts
join2_initial = join2infos[0].from_opts
if join1_final is join2_initial:
intermediate_infos = []
elif issubclass(join1_final.model, join2_initial.model):
intermediate_infos = join1_final.get_path_to_parent(join2_initial.model)
else:
intermediate_infos = join2_initial.get_path_from_parent(join1_final.model)
return [*join1infos, *intermediate_infos, *join2infos]
def get_path_info(self, filtered_relation=None):
return self._get_path_info(direct=True, filtered_relation=filtered_relation)
def get_reverse_path_info(self, filtered_relation=None):
return self._get_path_info(direct=False, filtered_relation=filtered_relation)
def _get_m2m_db_table(self, opts):
"""
Function that can be curried to provide the m2m table name for this
relation.
"""
if self.remote_field.through is not None:
return self.remote_field.through._meta.db_table
elif self.db_table:
return self.db_table
else:
m2m_table_name = '%s_%s' % (utils.strip_quotes(opts.db_table), self.name)
return utils.truncate_name(m2m_table_name, connection.ops.max_name_length())
def _get_m2m_attr(self, related, attr):
"""
Function that can be curried to provide the source accessor or DB
column name for the m2m table.
"""
cache_attr = '_m2m_%s_cache' % attr
if hasattr(self, cache_attr):
return getattr(self, cache_attr)
if self.remote_field.through_fields is not None:
link_field_name = self.remote_field.through_fields[0]
else:
link_field_name = None
for f in self.remote_field.through._meta.fields:
if (f.is_relation and f.remote_field.model == related.related_model and
(link_field_name is None or link_field_name == f.name)):
setattr(self, cache_attr, getattr(f, attr))
return getattr(self, cache_attr)
def _get_m2m_reverse_attr(self, related, attr):
"""
Function that can be curried to provide the related accessor or DB
column name for the m2m table.
"""
cache_attr = '_m2m_reverse_%s_cache' % attr
if hasattr(self, cache_attr):
return getattr(self, cache_attr)
found = False
if self.remote_field.through_fields is not None:
link_field_name = self.remote_field.through_fields[1]
else:
link_field_name = None
for f in self.remote_field.through._meta.fields:
if f.is_relation and f.remote_field.model == related.model:
if link_field_name is None and related.related_model == related.model:
# If this is an m2m-intermediate to self,
# the first foreign key you find will be
# the source column. Keep searching for
# the second foreign key.
if found:
setattr(self, cache_attr, getattr(f, attr))
break
else:
found = True
elif link_field_name is None or link_field_name == f.name:
setattr(self, cache_attr, getattr(f, attr))
break
return getattr(self, cache_attr)
def contribute_to_class(self, cls, name, **kwargs):
# To support multiple relations to self, it's useful to have a non-None
# related name on symmetrical relations for internal reasons. The
# concept doesn't make a lot of sense externally ("you want me to
# specify *what* on my non-reversible relation?!"), so we set it up
# automatically. The funky name reduces the chance of an accidental
# clash.
if self.remote_field.symmetrical and (
self.remote_field.model == RECURSIVE_RELATIONSHIP_CONSTANT or
self.remote_field.model == cls._meta.object_name
):
self.remote_field.related_name = "%s_rel_+" % name
elif self.remote_field.is_hidden():
# If the backwards relation is disabled, replace the original
# related_name with one generated from the m2m field name. Django
# still uses backwards relations internally and we need to avoid
# clashes between multiple m2m fields with related_name == '+'.
self.remote_field.related_name = "_%s_%s_+" % (cls.__name__.lower(), name)
super().contribute_to_class(cls, name, **kwargs)
# The intermediate m2m model is not auto created if:
# 1) There is a manually specified intermediate, or
# 2) The class owning the m2m field is abstract.
# 3) The class owning the m2m field has been swapped out.
if not cls._meta.abstract:
if self.remote_field.through:
def resolve_through_model(_, model, field):
field.remote_field.through = model
lazy_related_operation(resolve_through_model, cls, self.remote_field.through, field=self)
elif not cls._meta.swapped:
self.remote_field.through = create_many_to_many_intermediary_model(self, cls)
# Add the descriptor for the m2m relation.
setattr(cls, self.name, ManyToManyDescriptor(self.remote_field, reverse=False))
# Set up the accessor for the m2m table name for the relation.
self.m2m_db_table = partial(self._get_m2m_db_table, cls._meta)
def contribute_to_related_class(self, cls, related):
# Internal M2Ms (i.e., those with a related name ending with '+')
# and swapped models don't get a related descriptor.
if not self.remote_field.is_hidden() and not related.related_model._meta.swapped:
setattr(cls, related.get_accessor_name(), ManyToManyDescriptor(self.remote_field, reverse=True))
# Set up the accessors for the column names on the m2m table.
self.m2m_column_name = partial(self._get_m2m_attr, related, 'column')
self.m2m_reverse_name = partial(self._get_m2m_reverse_attr, related, 'column')
self.m2m_field_name = partial(self._get_m2m_attr, related, 'name')
self.m2m_reverse_field_name = partial(self._get_m2m_reverse_attr, related, 'name')
get_m2m_rel = partial(self._get_m2m_attr, related, 'remote_field')
self.m2m_target_field_name = lambda: get_m2m_rel().field_name
get_m2m_reverse_rel = partial(self._get_m2m_reverse_attr, related, 'remote_field')
self.m2m_reverse_target_field_name = lambda: get_m2m_reverse_rel().field_name
def set_attributes_from_rel(self):
pass
def value_from_object(self, obj):
return [] if obj.pk is None else list(getattr(obj, self.attname).all())
def save_form_data(self, instance, data):
getattr(instance, self.attname).set(data)
def formfield(self, *, using=None, **kwargs):
defaults = {
'form_class': forms.ModelMultipleChoiceField,
'queryset': self.remote_field.model._default_manager.using(using),
**kwargs,
}
# If initial is passed in, it's a list of related objects, but the
# MultipleChoiceField takes a list of IDs.
if defaults.get('initial') is not None:
initial = defaults['initial']
if callable(initial):
initial = initial()
defaults['initial'] = [i.pk for i in initial]
return super().formfield(**defaults)
def db_check(self, connection):
return None
def db_type(self, connection):
# A ManyToManyField is not represented by a single column,
# so return None.
return None
def db_parameters(self, connection):
return {"type": None, "check": None}
|
8dc8ad8f3fe55273e5e1b50973557b10726905aebfe8e9924ef7d825a90ae671 | import json
from django import forms
from django.core import checks, exceptions
from django.db import NotSupportedError, connections, router
from django.db.models import lookups
from django.db.models.lookups import PostgresOperatorLookup, Transform
from django.utils.translation import gettext_lazy as _
from . import Field
from .mixins import CheckFieldDefaultMixin
__all__ = ['JSONField']
class JSONField(CheckFieldDefaultMixin, Field):
empty_strings_allowed = False
description = _('A JSON object')
default_error_messages = {
'invalid': _('Value must be valid JSON.'),
}
_default_hint = ('dict', '{}')
def __init__(
self, verbose_name=None, name=None, encoder=None, decoder=None,
**kwargs,
):
if encoder and not callable(encoder):
raise ValueError('The encoder parameter must be a callable object.')
if decoder and not callable(decoder):
raise ValueError('The decoder parameter must be a callable object.')
self.encoder = encoder
self.decoder = decoder
super().__init__(verbose_name, name, **kwargs)
def check(self, **kwargs):
errors = super().check(**kwargs)
databases = kwargs.get('databases') or []
errors.extend(self._check_supported(databases))
return errors
def _check_supported(self, databases):
errors = []
for db in databases:
if not router.allow_migrate_model(db, self.model):
continue
connection = connections[db]
if not (
'supports_json_field' in self.model._meta.required_db_features or
connection.features.supports_json_field
):
errors.append(
checks.Error(
'%s does not support JSONFields.'
% connection.display_name,
obj=self.model,
id='fields.E180',
)
)
return errors
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if self.encoder is not None:
kwargs['encoder'] = self.encoder
if self.decoder is not None:
kwargs['decoder'] = self.decoder
return name, path, args, kwargs
def from_db_value(self, value, expression, connection):
if value is None:
return value
if connection.features.has_native_json_field and self.decoder is None:
return value
try:
return json.loads(value, cls=self.decoder)
except json.JSONDecodeError:
return value
def get_internal_type(self):
return 'JSONField'
def get_prep_value(self, value):
if value is None:
return value
return json.dumps(value, cls=self.encoder)
def get_transform(self, name):
transform = super().get_transform(name)
if transform:
return transform
return KeyTransformFactory(name)
def select_format(self, compiler, sql, params):
if (
compiler.connection.features.has_native_json_field and
self.decoder is not None
):
return compiler.connection.ops.json_cast_text_sql(sql), params
return super().select_format(compiler, sql, params)
def validate(self, value, model_instance):
super().validate(value, model_instance)
try:
json.dumps(value, cls=self.encoder)
except TypeError:
raise exceptions.ValidationError(
self.error_messages['invalid'],
code='invalid',
params={'value': value},
)
def value_to_string(self, obj):
return self.value_from_object(obj)
def formfield(self, **kwargs):
return super().formfield(**{
'form_class': forms.JSONField,
'encoder': self.encoder,
'decoder': self.decoder,
**kwargs,
})
def compile_json_path(key_transforms, include_root=True):
path = ['$'] if include_root else []
for key_transform in key_transforms:
try:
num = int(key_transform)
except ValueError: # non-integer
path.append('.')
path.append(json.dumps(key_transform))
else:
path.append('[%s]' % num)
return ''.join(path)
class DataContains(PostgresOperatorLookup):
lookup_name = 'contains'
postgres_operator = '@>'
def as_sql(self, compiler, connection):
lhs, lhs_params = self.process_lhs(compiler, connection)
rhs, rhs_params = self.process_rhs(compiler, connection)
params = tuple(lhs_params) + tuple(rhs_params)
return 'JSON_CONTAINS(%s, %s)' % (lhs, rhs), params
def as_oracle(self, compiler, connection):
if isinstance(self.rhs, KeyTransform):
return HasKey(self.lhs, self.rhs).as_oracle(compiler, connection)
lhs, lhs_params = self.process_lhs(compiler, connection)
params = tuple(lhs_params)
sql = (
"JSON_QUERY(%s, '$%s' WITH WRAPPER) = "
"JSON_QUERY('%s', '$.value' WITH WRAPPER)"
)
rhs = json.loads(self.rhs)
if isinstance(rhs, dict):
if not rhs:
return "DBMS_LOB.SUBSTR(%s) LIKE '{%%%%}'" % lhs, params
return ' AND '.join([
sql % (
lhs, '.%s' % json.dumps(key), json.dumps({'value': value}),
) for key, value in rhs.items()
]), params
return sql % (lhs, '', json.dumps({'value': rhs})), params
class ContainedBy(PostgresOperatorLookup):
lookup_name = 'contained_by'
postgres_operator = '<@'
def as_sql(self, compiler, connection):
lhs, lhs_params = self.process_lhs(compiler, connection)
rhs, rhs_params = self.process_rhs(compiler, connection)
params = tuple(rhs_params) + tuple(lhs_params)
return 'JSON_CONTAINS(%s, %s)' % (rhs, lhs), params
def as_oracle(self, compiler, connection):
raise NotSupportedError('contained_by lookup is not supported on Oracle.')
class HasKeyLookup(PostgresOperatorLookup):
logical_operator = None
def as_sql(self, compiler, connection, template=None):
# Process JSON path from the left-hand side.
if isinstance(self.lhs, KeyTransform):
lhs, lhs_params, lhs_key_transforms = self.lhs.preprocess_lhs(compiler, connection)
lhs_json_path = compile_json_path(lhs_key_transforms)
else:
lhs, lhs_params = self.process_lhs(compiler, connection)
lhs_json_path = '$'
sql = template % lhs
# Process JSON path from the right-hand side.
rhs = self.rhs
rhs_params = []
if not isinstance(rhs, (list, tuple)):
rhs = [rhs]
for key in rhs:
if isinstance(key, KeyTransform):
*_, rhs_key_transforms = key.preprocess_lhs(compiler, connection)
else:
rhs_key_transforms = [key]
rhs_params.append('%s%s' % (
lhs_json_path,
compile_json_path(rhs_key_transforms, include_root=False),
))
# Add condition for each key.
if self.logical_operator:
sql = '(%s)' % self.logical_operator.join([sql] * len(rhs_params))
return sql, tuple(lhs_params) + tuple(rhs_params)
def as_mysql(self, compiler, connection):
return self.as_sql(compiler, connection, template="JSON_CONTAINS_PATH(%s, 'one', %%s)")
def as_oracle(self, compiler, connection):
sql, params = self.as_sql(compiler, connection, template="JSON_EXISTS(%s, '%%s')")
# Add paths directly into SQL because path expressions cannot be passed
# as bind variables on Oracle.
return sql % tuple(params), []
def as_postgresql(self, compiler, connection):
if isinstance(self.rhs, KeyTransform):
*_, rhs_key_transforms = self.rhs.preprocess_lhs(compiler, connection)
for key in rhs_key_transforms[:-1]:
self.lhs = KeyTransform(key, self.lhs)
self.rhs = rhs_key_transforms[-1]
return super().as_postgresql(compiler, connection)
def as_sqlite(self, compiler, connection):
return self.as_sql(compiler, connection, template='JSON_TYPE(%s, %%s) IS NOT NULL')
class HasKey(HasKeyLookup):
lookup_name = 'has_key'
postgres_operator = '?'
prepare_rhs = False
class HasKeys(HasKeyLookup):
lookup_name = 'has_keys'
postgres_operator = '?&'
logical_operator = ' AND '
def get_prep_lookup(self):
return [str(item) for item in self.rhs]
class HasAnyKeys(HasKeys):
lookup_name = 'has_any_keys'
postgres_operator = '?|'
logical_operator = ' OR '
class JSONExact(lookups.Exact):
can_use_none_as_rhs = True
def process_lhs(self, compiler, connection):
lhs, lhs_params = super().process_lhs(compiler, connection)
if connection.vendor == 'sqlite':
rhs, rhs_params = super().process_rhs(compiler, connection)
if rhs == '%s' and rhs_params == [None]:
# Use JSON_TYPE instead of JSON_EXTRACT for NULLs.
lhs = "JSON_TYPE(%s, '$')" % lhs
return lhs, lhs_params
def process_rhs(self, compiler, connection):
rhs, rhs_params = super().process_rhs(compiler, connection)
# Treat None lookup values as null.
if rhs == '%s' and rhs_params == [None]:
rhs_params = ['null']
if connection.vendor == 'mysql':
func = ["JSON_EXTRACT(%s, '$')"] * len(rhs_params)
rhs = rhs % tuple(func)
return rhs, rhs_params
JSONField.register_lookup(DataContains)
JSONField.register_lookup(ContainedBy)
JSONField.register_lookup(HasKey)
JSONField.register_lookup(HasKeys)
JSONField.register_lookup(HasAnyKeys)
JSONField.register_lookup(JSONExact)
class KeyTransform(Transform):
postgres_operator = '->'
postgres_nested_operator = '#>'
def __init__(self, key_name, *args, **kwargs):
super().__init__(*args, **kwargs)
self.key_name = str(key_name)
def preprocess_lhs(self, compiler, connection, lhs_only=False):
if not lhs_only:
key_transforms = [self.key_name]
previous = self.lhs
while isinstance(previous, KeyTransform):
if not lhs_only:
key_transforms.insert(0, previous.key_name)
previous = previous.lhs
lhs, params = compiler.compile(previous)
if connection.vendor == 'oracle':
# Escape string-formatting.
key_transforms = [key.replace('%', '%%') for key in key_transforms]
return (lhs, params, key_transforms) if not lhs_only else (lhs, params)
def as_mysql(self, compiler, connection):
lhs, params, key_transforms = self.preprocess_lhs(compiler, connection)
json_path = compile_json_path(key_transforms)
return 'JSON_EXTRACT(%s, %%s)' % lhs, tuple(params) + (json_path,)
def as_oracle(self, compiler, connection):
lhs, params, key_transforms = self.preprocess_lhs(compiler, connection)
json_path = compile_json_path(key_transforms)
return (
"COALESCE(JSON_QUERY(%s, '%s'), JSON_VALUE(%s, '%s'))" %
((lhs, json_path) * 2)
), tuple(params) * 2
def as_postgresql(self, compiler, connection):
lhs, params, key_transforms = self.preprocess_lhs(compiler, connection)
if len(key_transforms) > 1:
return '(%s %s %%s)' % (lhs, self.postgres_nested_operator), params + [key_transforms]
try:
lookup = int(self.key_name)
except ValueError:
lookup = self.key_name
return '(%s %s %%s)' % (lhs, self.postgres_operator), tuple(params) + (lookup,)
def as_sqlite(self, compiler, connection):
lhs, params, key_transforms = self.preprocess_lhs(compiler, connection)
json_path = compile_json_path(key_transforms)
return 'JSON_EXTRACT(%s, %%s)' % lhs, tuple(params) + (json_path,)
class KeyTextTransform(KeyTransform):
postgres_operator = '->>'
postgres_nested_operator = '#>>'
class KeyTransformTextLookupMixin:
"""
Mixin for combining with a lookup expecting a text lhs from a JSONField
key lookup. On PostgreSQL, make use of the ->> operator instead of casting
key values to text and performing the lookup on the resulting
representation.
"""
def __init__(self, key_transform, *args, **kwargs):
if not isinstance(key_transform, KeyTransform):
raise TypeError(
'Transform should be an instance of KeyTransform in order to '
'use this lookup.'
)
key_text_transform = KeyTextTransform(
key_transform.key_name, *key_transform.source_expressions,
**key_transform.extra,
)
super().__init__(key_text_transform, *args, **kwargs)
class CaseInsensitiveMixin:
"""
Mixin to allow case-insensitive comparison of JSON values on MySQL.
MySQL handles strings used in JSON context using the utf8mb4_bin collation.
Because utf8mb4_bin is a binary collation, comparison of JSON values is
case-sensitive.
"""
def process_lhs(self, compiler, connection):
lhs, lhs_params = super().process_lhs(compiler, connection)
if connection.vendor == 'mysql':
return 'LOWER(%s)' % lhs, lhs_params
return lhs, lhs_params
def process_rhs(self, compiler, connection):
rhs, rhs_params = super().process_rhs(compiler, connection)
if connection.vendor == 'mysql':
return 'LOWER(%s)' % rhs, rhs_params
return rhs, rhs_params
class KeyTransformIsNull(lookups.IsNull):
# key__isnull=False is the same as has_key='key'
def as_oracle(self, compiler, connection):
if not self.rhs:
return HasKey(self.lhs.lhs, self.lhs.key_name).as_oracle(compiler, connection)
return super().as_sql(compiler, connection)
def as_sqlite(self, compiler, connection):
if not self.rhs:
return HasKey(self.lhs.lhs, self.lhs.key_name).as_sqlite(compiler, connection)
return super().as_sql(compiler, connection)
class KeyTransformExact(JSONExact):
def process_lhs(self, compiler, connection):
lhs, lhs_params = super().process_lhs(compiler, connection)
if connection.vendor == 'sqlite':
rhs, rhs_params = super().process_rhs(compiler, connection)
if rhs == '%s' and rhs_params == ['null']:
lhs, _ = self.lhs.preprocess_lhs(compiler, connection, lhs_only=True)
lhs = 'JSON_TYPE(%s, %%s)' % lhs
return lhs, lhs_params
def process_rhs(self, compiler, connection):
if isinstance(self.rhs, KeyTransform):
return super(lookups.Exact, self).process_rhs(compiler, connection)
rhs, rhs_params = super().process_rhs(compiler, connection)
if connection.vendor == 'oracle':
func = []
for value in rhs_params:
value = json.loads(value)
function = 'JSON_QUERY' if isinstance(value, (list, dict)) else 'JSON_VALUE'
func.append("%s('%s', '$.value')" % (
function,
json.dumps({'value': value}),
))
rhs = rhs % tuple(func)
rhs_params = []
elif connection.vendor == 'sqlite':
func = ["JSON_EXTRACT(%s, '$')" if value != 'null' else '%s' for value in rhs_params]
rhs = rhs % tuple(func)
return rhs, rhs_params
def as_oracle(self, compiler, connection):
rhs, rhs_params = super().process_rhs(compiler, connection)
if rhs_params == ['null']:
# Field has key and it's NULL.
has_key_expr = HasKey(self.lhs.lhs, self.lhs.key_name)
has_key_sql, has_key_params = has_key_expr.as_oracle(compiler, connection)
is_null_expr = self.lhs.get_lookup('isnull')(self.lhs, True)
is_null_sql, is_null_params = is_null_expr.as_sql(compiler, connection)
return (
'%s AND %s' % (has_key_sql, is_null_sql),
tuple(has_key_params) + tuple(is_null_params),
)
return super().as_sql(compiler, connection)
class KeyTransformIExact(CaseInsensitiveMixin, KeyTransformTextLookupMixin, lookups.IExact):
pass
class KeyTransformIContains(CaseInsensitiveMixin, KeyTransformTextLookupMixin, lookups.IContains):
pass
class KeyTransformContains(KeyTransformTextLookupMixin, lookups.Contains):
pass
class KeyTransformStartsWith(KeyTransformTextLookupMixin, lookups.StartsWith):
pass
class KeyTransformIStartsWith(CaseInsensitiveMixin, KeyTransformTextLookupMixin, lookups.IStartsWith):
pass
class KeyTransformEndsWith(KeyTransformTextLookupMixin, lookups.EndsWith):
pass
class KeyTransformIEndsWith(CaseInsensitiveMixin, KeyTransformTextLookupMixin, lookups.IEndsWith):
pass
class KeyTransformRegex(KeyTransformTextLookupMixin, lookups.Regex):
pass
class KeyTransformIRegex(CaseInsensitiveMixin, KeyTransformTextLookupMixin, lookups.IRegex):
pass
class KeyTransformNumericLookupMixin:
def process_rhs(self, compiler, connection):
rhs, rhs_params = super().process_rhs(compiler, connection)
if not connection.features.has_native_json_field:
rhs_params = [json.loads(value) for value in rhs_params]
return rhs, rhs_params
class KeyTransformLt(KeyTransformNumericLookupMixin, lookups.LessThan):
pass
class KeyTransformLte(KeyTransformNumericLookupMixin, lookups.LessThanOrEqual):
pass
class KeyTransformGt(KeyTransformNumericLookupMixin, lookups.GreaterThan):
pass
class KeyTransformGte(KeyTransformNumericLookupMixin, lookups.GreaterThanOrEqual):
pass
KeyTransform.register_lookup(KeyTransformExact)
KeyTransform.register_lookup(KeyTransformIExact)
KeyTransform.register_lookup(KeyTransformIsNull)
KeyTransform.register_lookup(KeyTransformContains)
KeyTransform.register_lookup(KeyTransformIContains)
KeyTransform.register_lookup(KeyTransformStartsWith)
KeyTransform.register_lookup(KeyTransformIStartsWith)
KeyTransform.register_lookup(KeyTransformEndsWith)
KeyTransform.register_lookup(KeyTransformIEndsWith)
KeyTransform.register_lookup(KeyTransformRegex)
KeyTransform.register_lookup(KeyTransformIRegex)
KeyTransform.register_lookup(KeyTransformLt)
KeyTransform.register_lookup(KeyTransformLte)
KeyTransform.register_lookup(KeyTransformGt)
KeyTransform.register_lookup(KeyTransformGte)
class KeyTransformFactory:
def __init__(self, key_name):
self.key_name = key_name
def __call__(self, *args, **kwargs):
return KeyTransform(self.key_name, *args, **kwargs)
|
e730065b62151d1d1ca095c7ec1438c2e5544407ab5cbb1c3fd8b195a1fd46be | import datetime
import posixpath
from django import forms
from django.core import checks
from django.core.files.base import File
from django.core.files.images import ImageFile
from django.core.files.storage import Storage, default_storage
from django.db.models import signals
from django.db.models.fields import Field
from django.utils.translation import gettext_lazy as _
class FieldFile(File):
def __init__(self, instance, field, name):
super().__init__(None, name)
self.instance = instance
self.field = field
self.storage = field.storage
self._committed = True
def __eq__(self, other):
# Older code may be expecting FileField values to be simple strings.
# By overriding the == operator, it can remain backwards compatibility.
if hasattr(other, 'name'):
return self.name == other.name
return self.name == other
def __hash__(self):
return hash(self.name)
# The standard File contains most of the necessary properties, but
# FieldFiles can be instantiated without a name, so that needs to
# be checked for here.
def _require_file(self):
if not self:
raise ValueError("The '%s' attribute has no file associated with it." % self.field.name)
def _get_file(self):
self._require_file()
if getattr(self, '_file', None) is None:
self._file = self.storage.open(self.name, 'rb')
return self._file
def _set_file(self, file):
self._file = file
def _del_file(self):
del self._file
file = property(_get_file, _set_file, _del_file)
@property
def path(self):
self._require_file()
return self.storage.path(self.name)
@property
def url(self):
self._require_file()
return self.storage.url(self.name)
@property
def size(self):
self._require_file()
if not self._committed:
return self.file.size
return self.storage.size(self.name)
def open(self, mode='rb'):
self._require_file()
if getattr(self, '_file', None) is None:
self.file = self.storage.open(self.name, mode)
else:
self.file.open(mode)
return self
# open() doesn't alter the file's contents, but it does reset the pointer
open.alters_data = True
# In addition to the standard File API, FieldFiles have extra methods
# to further manipulate the underlying file, as well as update the
# associated model instance.
def save(self, name, content, save=True):
name = self.field.generate_filename(self.instance, name)
self.name = self.storage.save(name, content, max_length=self.field.max_length)
setattr(self.instance, self.field.name, self.name)
self._committed = True
# Save the object because it has changed, unless save is False
if save:
self.instance.save()
save.alters_data = True
def delete(self, save=True):
if not self:
return
# Only close the file if it's already open, which we know by the
# presence of self._file
if hasattr(self, '_file'):
self.close()
del self.file
self.storage.delete(self.name)
self.name = None
setattr(self.instance, self.field.name, self.name)
self._committed = False
if save:
self.instance.save()
delete.alters_data = True
@property
def closed(self):
file = getattr(self, '_file', None)
return file is None or file.closed
def close(self):
file = getattr(self, '_file', None)
if file is not None:
file.close()
def __getstate__(self):
# FieldFile needs access to its associated model field, an instance and
# the file's name. Everything else will be restored later, by
# FileDescriptor below.
return {
'name': self.name,
'closed': False,
'_committed': True,
'_file': None,
'instance': self.instance,
'field': self.field,
}
def __setstate__(self, state):
self.__dict__.update(state)
self.storage = self.field.storage
class FileDescriptor:
"""
The descriptor for the file attribute on the model instance. Return a
FieldFile when accessed so you can write code like::
>>> from myapp.models import MyModel
>>> instance = MyModel.objects.get(pk=1)
>>> instance.file.size
Assign a file object on assignment so you can do::
>>> with open('/path/to/hello.world') as f:
... instance.file = File(f)
"""
def __init__(self, field):
self.field = field
def __get__(self, instance, cls=None):
if instance is None:
return self
# This is slightly complicated, so worth an explanation.
# instance.file`needs to ultimately return some instance of `File`,
# probably a subclass. Additionally, this returned object needs to have
# the FieldFile API so that users can easily do things like
# instance.file.path and have that delegated to the file storage engine.
# Easy enough if we're strict about assignment in __set__, but if you
# peek below you can see that we're not. So depending on the current
# value of the field we have to dynamically construct some sort of
# "thing" to return.
# The instance dict contains whatever was originally assigned
# in __set__.
if self.field.name in instance.__dict__:
file = instance.__dict__[self.field.name]
else:
instance.refresh_from_db(fields=[self.field.name])
file = getattr(instance, self.field.name)
# If this value is a string (instance.file = "path/to/file") or None
# then we simply wrap it with the appropriate attribute class according
# to the file field. [This is FieldFile for FileFields and
# ImageFieldFile for ImageFields; it's also conceivable that user
# subclasses might also want to subclass the attribute class]. This
# object understands how to convert a path to a file, and also how to
# handle None.
if isinstance(file, str) or file is None:
attr = self.field.attr_class(instance, self.field, file)
instance.__dict__[self.field.name] = attr
# Other types of files may be assigned as well, but they need to have
# the FieldFile interface added to them. Thus, we wrap any other type of
# File inside a FieldFile (well, the field's attr_class, which is
# usually FieldFile).
elif isinstance(file, File) and not isinstance(file, FieldFile):
file_copy = self.field.attr_class(instance, self.field, file.name)
file_copy.file = file
file_copy._committed = False
instance.__dict__[self.field.name] = file_copy
# Finally, because of the (some would say boneheaded) way pickle works,
# the underlying FieldFile might not actually itself have an associated
# file. So we need to reset the details of the FieldFile in those cases.
elif isinstance(file, FieldFile) and not hasattr(file, 'field'):
file.instance = instance
file.field = self.field
file.storage = self.field.storage
# Make sure that the instance is correct.
elif isinstance(file, FieldFile) and instance is not file.instance:
file.instance = instance
# That was fun, wasn't it?
return instance.__dict__[self.field.name]
def __set__(self, instance, value):
instance.__dict__[self.field.name] = value
class FileField(Field):
# The class to wrap instance attributes in. Accessing the file object off
# the instance will always return an instance of attr_class.
attr_class = FieldFile
# The descriptor to use for accessing the attribute off of the class.
descriptor_class = FileDescriptor
description = _("File")
def __init__(self, verbose_name=None, name=None, upload_to='', storage=None, **kwargs):
self._primary_key_set_explicitly = 'primary_key' in kwargs
self.storage = storage or default_storage
if callable(self.storage):
self.storage = self.storage()
if not isinstance(self.storage, Storage):
raise TypeError(
"%s.storage must be a subclass/instance of %s.%s"
% (self.__class__.__qualname__, Storage.__module__, Storage.__qualname__)
)
self.upload_to = upload_to
kwargs.setdefault('max_length', 100)
super().__init__(verbose_name, name, **kwargs)
def check(self, **kwargs):
return [
*super().check(**kwargs),
*self._check_primary_key(),
*self._check_upload_to(),
]
def _check_primary_key(self):
if self._primary_key_set_explicitly:
return [
checks.Error(
"'primary_key' is not a valid argument for a %s." % self.__class__.__name__,
obj=self,
id='fields.E201',
)
]
else:
return []
def _check_upload_to(self):
if isinstance(self.upload_to, str) and self.upload_to.startswith('/'):
return [
checks.Error(
"%s's 'upload_to' argument must be a relative path, not an "
"absolute path." % self.__class__.__name__,
obj=self,
id='fields.E202',
hint='Remove the leading slash.',
)
]
else:
return []
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if kwargs.get("max_length") == 100:
del kwargs["max_length"]
kwargs['upload_to'] = self.upload_to
if self.storage is not default_storage:
kwargs['storage'] = self.storage
return name, path, args, kwargs
def get_internal_type(self):
return "FileField"
def get_prep_value(self, value):
value = super().get_prep_value(value)
# Need to convert File objects provided via a form to string for database insertion
if value is None:
return None
return str(value)
def pre_save(self, model_instance, add):
file = super().pre_save(model_instance, add)
if file and not file._committed:
# Commit the file to storage prior to saving the model
file.save(file.name, file.file, save=False)
return file
def contribute_to_class(self, cls, name, **kwargs):
super().contribute_to_class(cls, name, **kwargs)
setattr(cls, self.name, self.descriptor_class(self))
def generate_filename(self, instance, filename):
"""
Apply (if callable) or prepend (if a string) upload_to to the filename,
then delegate further processing of the name to the storage backend.
Until the storage layer, all file paths are expected to be Unix style
(with forward slashes).
"""
if callable(self.upload_to):
filename = self.upload_to(instance, filename)
else:
dirname = datetime.datetime.now().strftime(str(self.upload_to))
filename = posixpath.join(dirname, filename)
return self.storage.generate_filename(filename)
def save_form_data(self, instance, data):
# Important: None means "no change", other false value means "clear"
# This subtle distinction (rather than a more explicit marker) is
# needed because we need to consume values that are also sane for a
# regular (non Model-) Form to find in its cleaned_data dictionary.
if data is not None:
# This value will be converted to str and stored in the
# database, so leaving False as-is is not acceptable.
setattr(instance, self.name, data or '')
def formfield(self, **kwargs):
return super().formfield(**{
'form_class': forms.FileField,
'max_length': self.max_length,
**kwargs,
})
class ImageFileDescriptor(FileDescriptor):
"""
Just like the FileDescriptor, but for ImageFields. The only difference is
assigning the width/height to the width_field/height_field, if appropriate.
"""
def __set__(self, instance, value):
previous_file = instance.__dict__.get(self.field.name)
super().__set__(instance, value)
# To prevent recalculating image dimensions when we are instantiating
# an object from the database (bug #11084), only update dimensions if
# the field had a value before this assignment. Since the default
# value for FileField subclasses is an instance of field.attr_class,
# previous_file will only be None when we are called from
# Model.__init__(). The ImageField.update_dimension_fields method
# hooked up to the post_init signal handles the Model.__init__() cases.
# Assignment happening outside of Model.__init__() will trigger the
# update right here.
if previous_file is not None:
self.field.update_dimension_fields(instance, force=True)
class ImageFieldFile(ImageFile, FieldFile):
def delete(self, save=True):
# Clear the image dimensions cache
if hasattr(self, '_dimensions_cache'):
del self._dimensions_cache
super().delete(save)
class ImageField(FileField):
attr_class = ImageFieldFile
descriptor_class = ImageFileDescriptor
description = _("Image")
def __init__(self, verbose_name=None, name=None, width_field=None, height_field=None, **kwargs):
self.width_field, self.height_field = width_field, height_field
super().__init__(verbose_name, name, **kwargs)
def check(self, **kwargs):
return [
*super().check(**kwargs),
*self._check_image_library_installed(),
]
def _check_image_library_installed(self):
try:
from PIL import Image # NOQA
except ImportError:
return [
checks.Error(
'Cannot use ImageField because Pillow is not installed.',
hint=('Get Pillow at https://pypi.org/project/Pillow/ '
'or run command "python -m pip install Pillow".'),
obj=self,
id='fields.E210',
)
]
else:
return []
def deconstruct(self):
name, path, args, kwargs = super().deconstruct()
if self.width_field:
kwargs['width_field'] = self.width_field
if self.height_field:
kwargs['height_field'] = self.height_field
return name, path, args, kwargs
def contribute_to_class(self, cls, name, **kwargs):
super().contribute_to_class(cls, name, **kwargs)
# Attach update_dimension_fields so that dimension fields declared
# after their corresponding image field don't stay cleared by
# Model.__init__, see bug #11196.
# Only run post-initialization dimension update on non-abstract models
if not cls._meta.abstract:
signals.post_init.connect(self.update_dimension_fields, sender=cls)
def update_dimension_fields(self, instance, force=False, *args, **kwargs):
"""
Update field's width and height fields, if defined.
This method is hooked up to model's post_init signal to update
dimensions after instantiating a model instance. However, dimensions
won't be updated if the dimensions fields are already populated. This
avoids unnecessary recalculation when loading an object from the
database.
Dimensions can be forced to update with force=True, which is how
ImageFileDescriptor.__set__ calls this method.
"""
# Nothing to update if the field doesn't have dimension fields or if
# the field is deferred.
has_dimension_fields = self.width_field or self.height_field
if not has_dimension_fields or self.attname not in instance.__dict__:
return
# getattr will call the ImageFileDescriptor's __get__ method, which
# coerces the assigned value into an instance of self.attr_class
# (ImageFieldFile in this case).
file = getattr(instance, self.attname)
# Nothing to update if we have no file and not being forced to update.
if not file and not force:
return
dimension_fields_filled = not(
(self.width_field and not getattr(instance, self.width_field)) or
(self.height_field and not getattr(instance, self.height_field))
)
# When both dimension fields have values, we are most likely loading
# data from the database or updating an image field that already had
# an image stored. In the first case, we don't want to update the
# dimension fields because we are already getting their values from the
# database. In the second case, we do want to update the dimensions
# fields and will skip this return because force will be True since we
# were called from ImageFileDescriptor.__set__.
if dimension_fields_filled and not force:
return
# file should be an instance of ImageFieldFile or should be None.
if file:
width = file.width
height = file.height
else:
# No file, so clear dimensions fields.
width = None
height = None
# Update the width and height fields.
if self.width_field:
setattr(instance, self.width_field, width)
if self.height_field:
setattr(instance, self.height_field, height)
def formfield(self, **kwargs):
return super().formfield(**{
'form_class': forms.ImageField,
**kwargs,
})
|
785694ba0c973cdfd3796d988b887abbd4ef4eaa685ea844c8a2b0a02186e0b4 | """
Accessors for related objects.
When a field defines a relation between two models, each model class provides
an attribute to access related instances of the other model class (unless the
reverse accessor has been disabled with related_name='+').
Accessors are implemented as descriptors in order to customize access and
assignment. This module defines the descriptor classes.
Forward accessors follow foreign keys. Reverse accessors trace them back. For
example, with the following models::
class Parent(Model):
pass
class Child(Model):
parent = ForeignKey(Parent, related_name='children')
``child.parent`` is a forward many-to-one relation. ``parent.children`` is a
reverse many-to-one relation.
There are three types of relations (many-to-one, one-to-one, and many-to-many)
and two directions (forward and reverse) for a total of six combinations.
1. Related instance on the forward side of a many-to-one relation:
``ForwardManyToOneDescriptor``.
Uniqueness of foreign key values is irrelevant to accessing the related
instance, making the many-to-one and one-to-one cases identical as far as
the descriptor is concerned. The constraint is checked upstream (unicity
validation in forms) or downstream (unique indexes in the database).
2. Related instance on the forward side of a one-to-one
relation: ``ForwardOneToOneDescriptor``.
It avoids querying the database when accessing the parent link field in
a multi-table inheritance scenario.
3. Related instance on the reverse side of a one-to-one relation:
``ReverseOneToOneDescriptor``.
One-to-one relations are asymmetrical, despite the apparent symmetry of the
name, because they're implemented in the database with a foreign key from
one table to another. As a consequence ``ReverseOneToOneDescriptor`` is
slightly different from ``ForwardManyToOneDescriptor``.
4. Related objects manager for related instances on the reverse side of a
many-to-one relation: ``ReverseManyToOneDescriptor``.
Unlike the previous two classes, this one provides access to a collection
of objects. It returns a manager rather than an instance.
5. Related objects manager for related instances on the forward or reverse
sides of a many-to-many relation: ``ManyToManyDescriptor``.
Many-to-many relations are symmetrical. The syntax of Django models
requires declaring them on one side but that's an implementation detail.
They could be declared on the other side without any change in behavior.
Therefore the forward and reverse descriptors can be the same.
If you're looking for ``ForwardManyToManyDescriptor`` or
``ReverseManyToManyDescriptor``, use ``ManyToManyDescriptor`` instead.
"""
from django.core.exceptions import FieldError
from django.db import connections, router, transaction
from django.db.models import Q, signals
from django.db.models.query import QuerySet
from django.db.models.query_utils import DeferredAttribute
from django.db.models.utils import resolve_callables
from django.utils.functional import cached_property
class ForeignKeyDeferredAttribute(DeferredAttribute):
def __set__(self, instance, value):
if instance.__dict__.get(self.field.attname) != value and self.field.is_cached(instance):
self.field.delete_cached_value(instance)
instance.__dict__[self.field.attname] = value
class ForwardManyToOneDescriptor:
"""
Accessor to the related object on the forward side of a many-to-one or
one-to-one (via ForwardOneToOneDescriptor subclass) relation.
In the example::
class Child(Model):
parent = ForeignKey(Parent, related_name='children')
``Child.parent`` is a ``ForwardManyToOneDescriptor`` instance.
"""
def __init__(self, field_with_rel):
self.field = field_with_rel
@cached_property
def RelatedObjectDoesNotExist(self):
# The exception can't be created at initialization time since the
# related model might not be resolved yet; `self.field.model` might
# still be a string model reference.
return type(
'RelatedObjectDoesNotExist',
(self.field.remote_field.model.DoesNotExist, AttributeError), {
'__module__': self.field.model.__module__,
'__qualname__': '%s.%s.RelatedObjectDoesNotExist' % (
self.field.model.__qualname__,
self.field.name,
),
}
)
def is_cached(self, instance):
return self.field.is_cached(instance)
def get_queryset(self, **hints):
return self.field.remote_field.model._base_manager.db_manager(hints=hints).all()
def get_prefetch_queryset(self, instances, queryset=None):
if queryset is None:
queryset = self.get_queryset()
queryset._add_hints(instance=instances[0])
rel_obj_attr = self.field.get_foreign_related_value
instance_attr = self.field.get_local_related_value
instances_dict = {instance_attr(inst): inst for inst in instances}
related_field = self.field.foreign_related_fields[0]
remote_field = self.field.remote_field
# FIXME: This will need to be revisited when we introduce support for
# composite fields. In the meantime we take this practical approach to
# solve a regression on 1.6 when the reverse manager in hidden
# (related_name ends with a '+'). Refs #21410.
# The check for len(...) == 1 is a special case that allows the query
# to be join-less and smaller. Refs #21760.
if remote_field.is_hidden() or len(self.field.foreign_related_fields) == 1:
query = {'%s__in' % related_field.name: {instance_attr(inst)[0] for inst in instances}}
else:
query = {'%s__in' % self.field.related_query_name(): instances}
queryset = queryset.filter(**query)
# Since we're going to assign directly in the cache,
# we must manage the reverse relation cache manually.
if not remote_field.multiple:
for rel_obj in queryset:
instance = instances_dict[rel_obj_attr(rel_obj)]
remote_field.set_cached_value(rel_obj, instance)
return queryset, rel_obj_attr, instance_attr, True, self.field.get_cache_name(), False
def get_object(self, instance):
qs = self.get_queryset(instance=instance)
# Assuming the database enforces foreign keys, this won't fail.
return qs.get(self.field.get_reverse_related_filter(instance))
def __get__(self, instance, cls=None):
"""
Get the related instance through the forward relation.
With the example above, when getting ``child.parent``:
- ``self`` is the descriptor managing the ``parent`` attribute
- ``instance`` is the ``child`` instance
- ``cls`` is the ``Child`` class (we don't need it)
"""
if instance is None:
return self
# The related instance is loaded from the database and then cached
# by the field on the model instance state. It can also be pre-cached
# by the reverse accessor (ReverseOneToOneDescriptor).
try:
rel_obj = self.field.get_cached_value(instance)
except KeyError:
has_value = None not in self.field.get_local_related_value(instance)
ancestor_link = instance._meta.get_ancestor_link(self.field.model) if has_value else None
if ancestor_link and ancestor_link.is_cached(instance):
# An ancestor link will exist if this field is defined on a
# multi-table inheritance parent of the instance's class.
ancestor = ancestor_link.get_cached_value(instance)
# The value might be cached on an ancestor if the instance
# originated from walking down the inheritance chain.
rel_obj = self.field.get_cached_value(ancestor, default=None)
else:
rel_obj = None
if rel_obj is None and has_value:
rel_obj = self.get_object(instance)
remote_field = self.field.remote_field
# If this is a one-to-one relation, set the reverse accessor
# cache on the related object to the current instance to avoid
# an extra SQL query if it's accessed later on.
if not remote_field.multiple:
remote_field.set_cached_value(rel_obj, instance)
self.field.set_cached_value(instance, rel_obj)
if rel_obj is None and not self.field.null:
raise self.RelatedObjectDoesNotExist(
"%s has no %s." % (self.field.model.__name__, self.field.name)
)
else:
return rel_obj
def __set__(self, instance, value):
"""
Set the related instance through the forward relation.
With the example above, when setting ``child.parent = parent``:
- ``self`` is the descriptor managing the ``parent`` attribute
- ``instance`` is the ``child`` instance
- ``value`` is the ``parent`` instance on the right of the equal sign
"""
# An object must be an instance of the related class.
if value is not None and not isinstance(value, self.field.remote_field.model._meta.concrete_model):
raise ValueError(
'Cannot assign "%r": "%s.%s" must be a "%s" instance.' % (
value,
instance._meta.object_name,
self.field.name,
self.field.remote_field.model._meta.object_name,
)
)
elif value is not None:
if instance._state.db is None:
instance._state.db = router.db_for_write(instance.__class__, instance=value)
if value._state.db is None:
value._state.db = router.db_for_write(value.__class__, instance=instance)
if not router.allow_relation(value, instance):
raise ValueError('Cannot assign "%r": the current database router prevents this relation.' % value)
remote_field = self.field.remote_field
# If we're setting the value of a OneToOneField to None, we need to clear
# out the cache on any old related object. Otherwise, deleting the
# previously-related object will also cause this object to be deleted,
# which is wrong.
if value is None:
# Look up the previously-related object, which may still be available
# since we've not yet cleared out the related field.
# Use the cache directly, instead of the accessor; if we haven't
# populated the cache, then we don't care - we're only accessing
# the object to invalidate the accessor cache, so there's no
# need to populate the cache just to expire it again.
related = self.field.get_cached_value(instance, default=None)
# If we've got an old related object, we need to clear out its
# cache. This cache also might not exist if the related object
# hasn't been accessed yet.
if related is not None:
remote_field.set_cached_value(related, None)
for lh_field, rh_field in self.field.related_fields:
setattr(instance, lh_field.attname, None)
# Set the values of the related field.
else:
for lh_field, rh_field in self.field.related_fields:
setattr(instance, lh_field.attname, getattr(value, rh_field.attname))
# Set the related instance cache used by __get__ to avoid an SQL query
# when accessing the attribute we just set.
self.field.set_cached_value(instance, value)
# If this is a one-to-one relation, set the reverse accessor cache on
# the related object to the current instance to avoid an extra SQL
# query if it's accessed later on.
if value is not None and not remote_field.multiple:
remote_field.set_cached_value(value, instance)
def __reduce__(self):
"""
Pickling should return the instance attached by self.field on the
model, not a new copy of that descriptor. Use getattr() to retrieve
the instance directly from the model.
"""
return getattr, (self.field.model, self.field.name)
class ForwardOneToOneDescriptor(ForwardManyToOneDescriptor):
"""
Accessor to the related object on the forward side of a one-to-one relation.
In the example::
class Restaurant(Model):
place = OneToOneField(Place, related_name='restaurant')
``Restaurant.place`` is a ``ForwardOneToOneDescriptor`` instance.
"""
def get_object(self, instance):
if self.field.remote_field.parent_link:
deferred = instance.get_deferred_fields()
# Because it's a parent link, all the data is available in the
# instance, so populate the parent model with this data.
rel_model = self.field.remote_field.model
fields = [field.attname for field in rel_model._meta.concrete_fields]
# If any of the related model's fields are deferred, fallback to
# fetching all fields from the related model. This avoids a query
# on the related model for every deferred field.
if not any(field in fields for field in deferred):
kwargs = {field: getattr(instance, field) for field in fields}
obj = rel_model(**kwargs)
obj._state.adding = instance._state.adding
obj._state.db = instance._state.db
return obj
return super().get_object(instance)
def __set__(self, instance, value):
super().__set__(instance, value)
# If the primary key is a link to a parent model and a parent instance
# is being set, update the value of the inherited pk(s).
if self.field.primary_key and self.field.remote_field.parent_link:
opts = instance._meta
# Inherited primary key fields from this object's base classes.
inherited_pk_fields = [
field for field in opts.concrete_fields
if field.primary_key and field.remote_field
]
for field in inherited_pk_fields:
rel_model_pk_name = field.remote_field.model._meta.pk.attname
raw_value = getattr(value, rel_model_pk_name) if value is not None else None
setattr(instance, rel_model_pk_name, raw_value)
class ReverseOneToOneDescriptor:
"""
Accessor to the related object on the reverse side of a one-to-one
relation.
In the example::
class Restaurant(Model):
place = OneToOneField(Place, related_name='restaurant')
``Place.restaurant`` is a ``ReverseOneToOneDescriptor`` instance.
"""
def __init__(self, related):
# Following the example above, `related` is an instance of OneToOneRel
# which represents the reverse restaurant field (place.restaurant).
self.related = related
@cached_property
def RelatedObjectDoesNotExist(self):
# The exception isn't created at initialization time for the sake of
# consistency with `ForwardManyToOneDescriptor`.
return type(
'RelatedObjectDoesNotExist',
(self.related.related_model.DoesNotExist, AttributeError), {
'__module__': self.related.model.__module__,
'__qualname__': '%s.%s.RelatedObjectDoesNotExist' % (
self.related.model.__qualname__,
self.related.name,
)
},
)
def is_cached(self, instance):
return self.related.is_cached(instance)
def get_queryset(self, **hints):
return self.related.related_model._base_manager.db_manager(hints=hints).all()
def get_prefetch_queryset(self, instances, queryset=None):
if queryset is None:
queryset = self.get_queryset()
queryset._add_hints(instance=instances[0])
rel_obj_attr = self.related.field.get_local_related_value
instance_attr = self.related.field.get_foreign_related_value
instances_dict = {instance_attr(inst): inst for inst in instances}
query = {'%s__in' % self.related.field.name: instances}
queryset = queryset.filter(**query)
# Since we're going to assign directly in the cache,
# we must manage the reverse relation cache manually.
for rel_obj in queryset:
instance = instances_dict[rel_obj_attr(rel_obj)]
self.related.field.set_cached_value(rel_obj, instance)
return queryset, rel_obj_attr, instance_attr, True, self.related.get_cache_name(), False
def __get__(self, instance, cls=None):
"""
Get the related instance through the reverse relation.
With the example above, when getting ``place.restaurant``:
- ``self`` is the descriptor managing the ``restaurant`` attribute
- ``instance`` is the ``place`` instance
- ``cls`` is the ``Place`` class (unused)
Keep in mind that ``Restaurant`` holds the foreign key to ``Place``.
"""
if instance is None:
return self
# The related instance is loaded from the database and then cached
# by the field on the model instance state. It can also be pre-cached
# by the forward accessor (ForwardManyToOneDescriptor).
try:
rel_obj = self.related.get_cached_value(instance)
except KeyError:
related_pk = instance.pk
if related_pk is None:
rel_obj = None
else:
filter_args = self.related.field.get_forward_related_filter(instance)
try:
rel_obj = self.get_queryset(instance=instance).get(**filter_args)
except self.related.related_model.DoesNotExist:
rel_obj = None
else:
# Set the forward accessor cache on the related object to
# the current instance to avoid an extra SQL query if it's
# accessed later on.
self.related.field.set_cached_value(rel_obj, instance)
self.related.set_cached_value(instance, rel_obj)
if rel_obj is None:
raise self.RelatedObjectDoesNotExist(
"%s has no %s." % (
instance.__class__.__name__,
self.related.get_accessor_name()
)
)
else:
return rel_obj
def __set__(self, instance, value):
"""
Set the related instance through the reverse relation.
With the example above, when setting ``place.restaurant = restaurant``:
- ``self`` is the descriptor managing the ``restaurant`` attribute
- ``instance`` is the ``place`` instance
- ``value`` is the ``restaurant`` instance on the right of the equal sign
Keep in mind that ``Restaurant`` holds the foreign key to ``Place``.
"""
# The similarity of the code below to the code in
# ForwardManyToOneDescriptor is annoying, but there's a bunch
# of small differences that would make a common base class convoluted.
if value is None:
# Update the cached related instance (if any) & clear the cache.
# Following the example above, this would be the cached
# ``restaurant`` instance (if any).
rel_obj = self.related.get_cached_value(instance, default=None)
if rel_obj is not None:
# Remove the ``restaurant`` instance from the ``place``
# instance cache.
self.related.delete_cached_value(instance)
# Set the ``place`` field on the ``restaurant``
# instance to None.
setattr(rel_obj, self.related.field.name, None)
elif not isinstance(value, self.related.related_model):
# An object must be an instance of the related class.
raise ValueError(
'Cannot assign "%r": "%s.%s" must be a "%s" instance.' % (
value,
instance._meta.object_name,
self.related.get_accessor_name(),
self.related.related_model._meta.object_name,
)
)
else:
if instance._state.db is None:
instance._state.db = router.db_for_write(instance.__class__, instance=value)
if value._state.db is None:
value._state.db = router.db_for_write(value.__class__, instance=instance)
if not router.allow_relation(value, instance):
raise ValueError('Cannot assign "%r": the current database router prevents this relation.' % value)
related_pk = tuple(getattr(instance, field.attname) for field in self.related.field.foreign_related_fields)
# Set the value of the related field to the value of the related object's related field
for index, field in enumerate(self.related.field.local_related_fields):
setattr(value, field.attname, related_pk[index])
# Set the related instance cache used by __get__ to avoid an SQL query
# when accessing the attribute we just set.
self.related.set_cached_value(instance, value)
# Set the forward accessor cache on the related object to the current
# instance to avoid an extra SQL query if it's accessed later on.
self.related.field.set_cached_value(value, instance)
def __reduce__(self):
# Same purpose as ForwardManyToOneDescriptor.__reduce__().
return getattr, (self.related.model, self.related.name)
class ReverseManyToOneDescriptor:
"""
Accessor to the related objects manager on the reverse side of a
many-to-one relation.
In the example::
class Child(Model):
parent = ForeignKey(Parent, related_name='children')
``Parent.children`` is a ``ReverseManyToOneDescriptor`` instance.
Most of the implementation is delegated to a dynamically defined manager
class built by ``create_forward_many_to_many_manager()`` defined below.
"""
def __init__(self, rel):
self.rel = rel
self.field = rel.field
@cached_property
def related_manager_cls(self):
related_model = self.rel.related_model
return create_reverse_many_to_one_manager(
related_model._default_manager.__class__,
self.rel,
)
def __get__(self, instance, cls=None):
"""
Get the related objects through the reverse relation.
With the example above, when getting ``parent.children``:
- ``self`` is the descriptor managing the ``children`` attribute
- ``instance`` is the ``parent`` instance
- ``cls`` is the ``Parent`` class (unused)
"""
if instance is None:
return self
return self.related_manager_cls(instance)
def _get_set_deprecation_msg_params(self):
return (
'reverse side of a related set',
self.rel.get_accessor_name(),
)
def __set__(self, instance, value):
raise TypeError(
'Direct assignment to the %s is prohibited. Use %s.set() instead.'
% self._get_set_deprecation_msg_params(),
)
def create_reverse_many_to_one_manager(superclass, rel):
"""
Create a manager for the reverse side of a many-to-one relation.
This manager subclasses another manager, generally the default manager of
the related model, and adds behaviors specific to many-to-one relations.
"""
class RelatedManager(superclass):
def __init__(self, instance):
super().__init__()
self.instance = instance
self.model = rel.related_model
self.field = rel.field
self.core_filters = {self.field.name: instance}
def __call__(self, *, manager):
manager = getattr(self.model, manager)
manager_class = create_reverse_many_to_one_manager(manager.__class__, rel)
return manager_class(self.instance)
do_not_call_in_templates = True
def _apply_rel_filters(self, queryset):
"""
Filter the queryset for the instance this manager is bound to.
"""
db = self._db or router.db_for_read(self.model, instance=self.instance)
empty_strings_as_null = connections[db].features.interprets_empty_strings_as_nulls
queryset._add_hints(instance=self.instance)
if self._db:
queryset = queryset.using(self._db)
queryset = queryset.filter(**self.core_filters)
for field in self.field.foreign_related_fields:
val = getattr(self.instance, field.attname)
if val is None or (val == '' and empty_strings_as_null):
return queryset.none()
if self.field.many_to_one:
# Guard against field-like objects such as GenericRelation
# that abuse create_reverse_many_to_one_manager() with reverse
# one-to-many relationships instead and break known related
# objects assignment.
try:
target_field = self.field.target_field
except FieldError:
# The relationship has multiple target fields. Use a tuple
# for related object id.
rel_obj_id = tuple([
getattr(self.instance, target_field.attname)
for target_field in self.field.get_path_info()[-1].target_fields
])
else:
rel_obj_id = getattr(self.instance, target_field.attname)
queryset._known_related_objects = {self.field: {rel_obj_id: self.instance}}
return queryset
def _remove_prefetched_objects(self):
try:
self.instance._prefetched_objects_cache.pop(self.field.remote_field.get_cache_name())
except (AttributeError, KeyError):
pass # nothing to clear from cache
def get_queryset(self):
try:
return self.instance._prefetched_objects_cache[self.field.remote_field.get_cache_name()]
except (AttributeError, KeyError):
queryset = super().get_queryset()
return self._apply_rel_filters(queryset)
def get_prefetch_queryset(self, instances, queryset=None):
if queryset is None:
queryset = super().get_queryset()
queryset._add_hints(instance=instances[0])
queryset = queryset.using(queryset._db or self._db)
rel_obj_attr = self.field.get_local_related_value
instance_attr = self.field.get_foreign_related_value
instances_dict = {instance_attr(inst): inst for inst in instances}
query = {'%s__in' % self.field.name: instances}
queryset = queryset.filter(**query)
# Since we just bypassed this class' get_queryset(), we must manage
# the reverse relation manually.
for rel_obj in queryset:
instance = instances_dict[rel_obj_attr(rel_obj)]
setattr(rel_obj, self.field.name, instance)
cache_name = self.field.remote_field.get_cache_name()
return queryset, rel_obj_attr, instance_attr, False, cache_name, False
def add(self, *objs, bulk=True):
self._remove_prefetched_objects()
objs = list(objs)
db = router.db_for_write(self.model, instance=self.instance)
def check_and_update_obj(obj):
if not isinstance(obj, self.model):
raise TypeError("'%s' instance expected, got %r" % (
self.model._meta.object_name, obj,
))
setattr(obj, self.field.name, self.instance)
if bulk:
pks = []
for obj in objs:
check_and_update_obj(obj)
if obj._state.adding or obj._state.db != db:
raise ValueError(
"%r instance isn't saved. Use bulk=False or save "
"the object first." % obj
)
pks.append(obj.pk)
self.model._base_manager.using(db).filter(pk__in=pks).update(**{
self.field.name: self.instance,
})
else:
with transaction.atomic(using=db, savepoint=False):
for obj in objs:
check_and_update_obj(obj)
obj.save()
add.alters_data = True
def create(self, **kwargs):
kwargs[self.field.name] = self.instance
db = router.db_for_write(self.model, instance=self.instance)
return super(RelatedManager, self.db_manager(db)).create(**kwargs)
create.alters_data = True
def get_or_create(self, **kwargs):
kwargs[self.field.name] = self.instance
db = router.db_for_write(self.model, instance=self.instance)
return super(RelatedManager, self.db_manager(db)).get_or_create(**kwargs)
get_or_create.alters_data = True
def update_or_create(self, **kwargs):
kwargs[self.field.name] = self.instance
db = router.db_for_write(self.model, instance=self.instance)
return super(RelatedManager, self.db_manager(db)).update_or_create(**kwargs)
update_or_create.alters_data = True
# remove() and clear() are only provided if the ForeignKey can have a value of null.
if rel.field.null:
def remove(self, *objs, bulk=True):
if not objs:
return
val = self.field.get_foreign_related_value(self.instance)
old_ids = set()
for obj in objs:
if not isinstance(obj, self.model):
raise TypeError("'%s' instance expected, got %r" % (
self.model._meta.object_name, obj,
))
# Is obj actually part of this descriptor set?
if self.field.get_local_related_value(obj) == val:
old_ids.add(obj.pk)
else:
raise self.field.remote_field.model.DoesNotExist(
"%r is not related to %r." % (obj, self.instance)
)
self._clear(self.filter(pk__in=old_ids), bulk)
remove.alters_data = True
def clear(self, *, bulk=True):
self._clear(self, bulk)
clear.alters_data = True
def _clear(self, queryset, bulk):
self._remove_prefetched_objects()
db = router.db_for_write(self.model, instance=self.instance)
queryset = queryset.using(db)
if bulk:
# `QuerySet.update()` is intrinsically atomic.
queryset.update(**{self.field.name: None})
else:
with transaction.atomic(using=db, savepoint=False):
for obj in queryset:
setattr(obj, self.field.name, None)
obj.save(update_fields=[self.field.name])
_clear.alters_data = True
def set(self, objs, *, bulk=True, clear=False):
# Force evaluation of `objs` in case it's a queryset whose value
# could be affected by `manager.clear()`. Refs #19816.
objs = tuple(objs)
if self.field.null:
db = router.db_for_write(self.model, instance=self.instance)
with transaction.atomic(using=db, savepoint=False):
if clear:
self.clear(bulk=bulk)
self.add(*objs, bulk=bulk)
else:
old_objs = set(self.using(db).all())
new_objs = []
for obj in objs:
if obj in old_objs:
old_objs.remove(obj)
else:
new_objs.append(obj)
self.remove(*old_objs, bulk=bulk)
self.add(*new_objs, bulk=bulk)
else:
self.add(*objs, bulk=bulk)
set.alters_data = True
return RelatedManager
class ManyToManyDescriptor(ReverseManyToOneDescriptor):
"""
Accessor to the related objects manager on the forward and reverse sides of
a many-to-many relation.
In the example::
class Pizza(Model):
toppings = ManyToManyField(Topping, related_name='pizzas')
``Pizza.toppings`` and ``Topping.pizzas`` are ``ManyToManyDescriptor``
instances.
Most of the implementation is delegated to a dynamically defined manager
class built by ``create_forward_many_to_many_manager()`` defined below.
"""
def __init__(self, rel, reverse=False):
super().__init__(rel)
self.reverse = reverse
@property
def through(self):
# through is provided so that you have easy access to the through
# model (Book.authors.through) for inlines, etc. This is done as
# a property to ensure that the fully resolved value is returned.
return self.rel.through
@cached_property
def related_manager_cls(self):
related_model = self.rel.related_model if self.reverse else self.rel.model
return create_forward_many_to_many_manager(
related_model._default_manager.__class__,
self.rel,
reverse=self.reverse,
)
def _get_set_deprecation_msg_params(self):
return (
'%s side of a many-to-many set' % ('reverse' if self.reverse else 'forward'),
self.rel.get_accessor_name() if self.reverse else self.field.name,
)
def create_forward_many_to_many_manager(superclass, rel, reverse):
"""
Create a manager for the either side of a many-to-many relation.
This manager subclasses another manager, generally the default manager of
the related model, and adds behaviors specific to many-to-many relations.
"""
class ManyRelatedManager(superclass):
def __init__(self, instance=None):
super().__init__()
self.instance = instance
if not reverse:
self.model = rel.model
self.query_field_name = rel.field.related_query_name()
self.prefetch_cache_name = rel.field.name
self.source_field_name = rel.field.m2m_field_name()
self.target_field_name = rel.field.m2m_reverse_field_name()
self.symmetrical = rel.symmetrical
else:
self.model = rel.related_model
self.query_field_name = rel.field.name
self.prefetch_cache_name = rel.field.related_query_name()
self.source_field_name = rel.field.m2m_reverse_field_name()
self.target_field_name = rel.field.m2m_field_name()
self.symmetrical = False
self.through = rel.through
self.reverse = reverse
self.source_field = self.through._meta.get_field(self.source_field_name)
self.target_field = self.through._meta.get_field(self.target_field_name)
self.core_filters = {}
self.pk_field_names = {}
for lh_field, rh_field in self.source_field.related_fields:
core_filter_key = '%s__%s' % (self.query_field_name, rh_field.name)
self.core_filters[core_filter_key] = getattr(instance, rh_field.attname)
self.pk_field_names[lh_field.name] = rh_field.name
self.related_val = self.source_field.get_foreign_related_value(instance)
if None in self.related_val:
raise ValueError('"%r" needs to have a value for field "%s" before '
'this many-to-many relationship can be used.' %
(instance, self.pk_field_names[self.source_field_name]))
# Even if this relation is not to pk, we require still pk value.
# The wish is that the instance has been already saved to DB,
# although having a pk value isn't a guarantee of that.
if instance.pk is None:
raise ValueError("%r instance needs to have a primary key value before "
"a many-to-many relationship can be used." %
instance.__class__.__name__)
def __call__(self, *, manager):
manager = getattr(self.model, manager)
manager_class = create_forward_many_to_many_manager(manager.__class__, rel, reverse)
return manager_class(instance=self.instance)
do_not_call_in_templates = True
def _build_remove_filters(self, removed_vals):
filters = Q(**{self.source_field_name: self.related_val})
# No need to add a subquery condition if removed_vals is a QuerySet without
# filters.
removed_vals_filters = (not isinstance(removed_vals, QuerySet) or
removed_vals._has_filters())
if removed_vals_filters:
filters &= Q(**{'%s__in' % self.target_field_name: removed_vals})
if self.symmetrical:
symmetrical_filters = Q(**{self.target_field_name: self.related_val})
if removed_vals_filters:
symmetrical_filters &= Q(
**{'%s__in' % self.source_field_name: removed_vals})
filters |= symmetrical_filters
return filters
def _apply_rel_filters(self, queryset):
"""
Filter the queryset for the instance this manager is bound to.
"""
queryset._add_hints(instance=self.instance)
if self._db:
queryset = queryset.using(self._db)
queryset._defer_next_filter = True
return queryset._next_is_sticky().filter(**self.core_filters)
def _remove_prefetched_objects(self):
try:
self.instance._prefetched_objects_cache.pop(self.prefetch_cache_name)
except (AttributeError, KeyError):
pass # nothing to clear from cache
def get_queryset(self):
try:
return self.instance._prefetched_objects_cache[self.prefetch_cache_name]
except (AttributeError, KeyError):
queryset = super().get_queryset()
return self._apply_rel_filters(queryset)
def get_prefetch_queryset(self, instances, queryset=None):
if queryset is None:
queryset = super().get_queryset()
queryset._add_hints(instance=instances[0])
queryset = queryset.using(queryset._db or self._db)
query = {'%s__in' % self.query_field_name: instances}
queryset = queryset._next_is_sticky().filter(**query)
# M2M: need to annotate the query in order to get the primary model
# that the secondary model was actually related to. We know that
# there will already be a join on the join table, so we can just add
# the select.
# For non-autocreated 'through' models, can't assume we are
# dealing with PK values.
fk = self.through._meta.get_field(self.source_field_name)
join_table = fk.model._meta.db_table
connection = connections[queryset.db]
qn = connection.ops.quote_name
queryset = queryset.extra(select={
'_prefetch_related_val_%s' % f.attname:
'%s.%s' % (qn(join_table), qn(f.column)) for f in fk.local_related_fields})
return (
queryset,
lambda result: tuple(
getattr(result, '_prefetch_related_val_%s' % f.attname)
for f in fk.local_related_fields
),
lambda inst: tuple(
f.get_db_prep_value(getattr(inst, f.attname), connection)
for f in fk.foreign_related_fields
),
False,
self.prefetch_cache_name,
False,
)
def add(self, *objs, through_defaults=None):
self._remove_prefetched_objects()
db = router.db_for_write(self.through, instance=self.instance)
with transaction.atomic(using=db, savepoint=False):
self._add_items(
self.source_field_name, self.target_field_name, *objs,
through_defaults=through_defaults,
)
# If this is a symmetrical m2m relation to self, add the mirror
# entry in the m2m table.
if self.symmetrical:
self._add_items(
self.target_field_name,
self.source_field_name,
*objs,
through_defaults=through_defaults,
)
add.alters_data = True
def remove(self, *objs):
self._remove_prefetched_objects()
self._remove_items(self.source_field_name, self.target_field_name, *objs)
remove.alters_data = True
def clear(self):
db = router.db_for_write(self.through, instance=self.instance)
with transaction.atomic(using=db, savepoint=False):
signals.m2m_changed.send(
sender=self.through, action="pre_clear",
instance=self.instance, reverse=self.reverse,
model=self.model, pk_set=None, using=db,
)
self._remove_prefetched_objects()
filters = self._build_remove_filters(super().get_queryset().using(db))
self.through._default_manager.using(db).filter(filters).delete()
signals.m2m_changed.send(
sender=self.through, action="post_clear",
instance=self.instance, reverse=self.reverse,
model=self.model, pk_set=None, using=db,
)
clear.alters_data = True
def set(self, objs, *, clear=False, through_defaults=None):
# Force evaluation of `objs` in case it's a queryset whose value
# could be affected by `manager.clear()`. Refs #19816.
objs = tuple(objs)
db = router.db_for_write(self.through, instance=self.instance)
with transaction.atomic(using=db, savepoint=False):
if clear:
self.clear()
self.add(*objs, through_defaults=through_defaults)
else:
old_ids = set(self.using(db).values_list(self.target_field.target_field.attname, flat=True))
new_objs = []
for obj in objs:
fk_val = (
self.target_field.get_foreign_related_value(obj)[0]
if isinstance(obj, self.model)
else self.target_field.get_prep_value(obj)
)
if fk_val in old_ids:
old_ids.remove(fk_val)
else:
new_objs.append(obj)
self.remove(*old_ids)
self.add(*new_objs, through_defaults=through_defaults)
set.alters_data = True
def create(self, *, through_defaults=None, **kwargs):
db = router.db_for_write(self.instance.__class__, instance=self.instance)
new_obj = super(ManyRelatedManager, self.db_manager(db)).create(**kwargs)
self.add(new_obj, through_defaults=through_defaults)
return new_obj
create.alters_data = True
def get_or_create(self, *, through_defaults=None, **kwargs):
db = router.db_for_write(self.instance.__class__, instance=self.instance)
obj, created = super(ManyRelatedManager, self.db_manager(db)).get_or_create(**kwargs)
# We only need to add() if created because if we got an object back
# from get() then the relationship already exists.
if created:
self.add(obj, through_defaults=through_defaults)
return obj, created
get_or_create.alters_data = True
def update_or_create(self, *, through_defaults=None, **kwargs):
db = router.db_for_write(self.instance.__class__, instance=self.instance)
obj, created = super(ManyRelatedManager, self.db_manager(db)).update_or_create(**kwargs)
# We only need to add() if created because if we got an object back
# from get() then the relationship already exists.
if created:
self.add(obj, through_defaults=through_defaults)
return obj, created
update_or_create.alters_data = True
def _get_target_ids(self, target_field_name, objs):
"""
Return the set of ids of `objs` that the target field references.
"""
from django.db.models import Model
target_ids = set()
target_field = self.through._meta.get_field(target_field_name)
for obj in objs:
if isinstance(obj, self.model):
if not router.allow_relation(obj, self.instance):
raise ValueError(
'Cannot add "%r": instance is on database "%s", '
'value is on database "%s"' %
(obj, self.instance._state.db, obj._state.db)
)
target_id = target_field.get_foreign_related_value(obj)[0]
if target_id is None:
raise ValueError(
'Cannot add "%r": the value for field "%s" is None' %
(obj, target_field_name)
)
target_ids.add(target_id)
elif isinstance(obj, Model):
raise TypeError(
"'%s' instance expected, got %r" %
(self.model._meta.object_name, obj)
)
else:
target_ids.add(target_field.get_prep_value(obj))
return target_ids
def _get_missing_target_ids(self, source_field_name, target_field_name, db, target_ids):
"""
Return the subset of ids of `objs` that aren't already assigned to
this relationship.
"""
vals = self.through._default_manager.using(db).values_list(
target_field_name, flat=True
).filter(**{
source_field_name: self.related_val[0],
'%s__in' % target_field_name: target_ids,
})
return target_ids.difference(vals)
def _get_add_plan(self, db, source_field_name):
"""
Return a boolean triple of the way the add should be performed.
The first element is whether or not bulk_create(ignore_conflicts)
can be used, the second whether or not signals must be sent, and
the third element is whether or not the immediate bulk insertion
with conflicts ignored can be performed.
"""
# Conflicts can be ignored when the intermediary model is
# auto-created as the only possible collision is on the
# (source_id, target_id) tuple. The same assertion doesn't hold for
# user-defined intermediary models as they could have other fields
# causing conflicts which must be surfaced.
can_ignore_conflicts = (
connections[db].features.supports_ignore_conflicts and
self.through._meta.auto_created is not False
)
# Don't send the signal when inserting duplicate data row
# for symmetrical reverse entries.
must_send_signals = (self.reverse or source_field_name == self.source_field_name) and (
signals.m2m_changed.has_listeners(self.through)
)
# Fast addition through bulk insertion can only be performed
# if no m2m_changed listeners are connected for self.through
# as they require the added set of ids to be provided via
# pk_set.
return can_ignore_conflicts, must_send_signals, (can_ignore_conflicts and not must_send_signals)
def _add_items(self, source_field_name, target_field_name, *objs, through_defaults=None):
# source_field_name: the PK fieldname in join table for the source object
# target_field_name: the PK fieldname in join table for the target object
# *objs - objects to add. Either object instances, or primary keys of object instances.
if not objs:
return
through_defaults = dict(resolve_callables(through_defaults or {}))
target_ids = self._get_target_ids(target_field_name, objs)
db = router.db_for_write(self.through, instance=self.instance)
can_ignore_conflicts, must_send_signals, can_fast_add = self._get_add_plan(db, source_field_name)
if can_fast_add:
self.through._default_manager.using(db).bulk_create([
self.through(**{
'%s_id' % source_field_name: self.related_val[0],
'%s_id' % target_field_name: target_id,
})
for target_id in target_ids
], ignore_conflicts=True)
return
missing_target_ids = self._get_missing_target_ids(
source_field_name, target_field_name, db, target_ids
)
with transaction.atomic(using=db, savepoint=False):
if must_send_signals:
signals.m2m_changed.send(
sender=self.through, action='pre_add',
instance=self.instance, reverse=self.reverse,
model=self.model, pk_set=missing_target_ids, using=db,
)
# Add the ones that aren't there already.
self.through._default_manager.using(db).bulk_create([
self.through(**through_defaults, **{
'%s_id' % source_field_name: self.related_val[0],
'%s_id' % target_field_name: target_id,
})
for target_id in missing_target_ids
], ignore_conflicts=can_ignore_conflicts)
if must_send_signals:
signals.m2m_changed.send(
sender=self.through, action='post_add',
instance=self.instance, reverse=self.reverse,
model=self.model, pk_set=missing_target_ids, using=db,
)
def _remove_items(self, source_field_name, target_field_name, *objs):
# source_field_name: the PK colname in join table for the source object
# target_field_name: the PK colname in join table for the target object
# *objs - objects to remove. Either object instances, or primary
# keys of object instances.
if not objs:
return
# Check that all the objects are of the right type
old_ids = set()
for obj in objs:
if isinstance(obj, self.model):
fk_val = self.target_field.get_foreign_related_value(obj)[0]
old_ids.add(fk_val)
else:
old_ids.add(obj)
db = router.db_for_write(self.through, instance=self.instance)
with transaction.atomic(using=db, savepoint=False):
# Send a signal to the other end if need be.
signals.m2m_changed.send(
sender=self.through, action="pre_remove",
instance=self.instance, reverse=self.reverse,
model=self.model, pk_set=old_ids, using=db,
)
target_model_qs = super().get_queryset()
if target_model_qs._has_filters():
old_vals = target_model_qs.using(db).filter(**{
'%s__in' % self.target_field.target_field.attname: old_ids})
else:
old_vals = old_ids
filters = self._build_remove_filters(old_vals)
self.through._default_manager.using(db).filter(filters).delete()
signals.m2m_changed.send(
sender=self.through, action="post_remove",
instance=self.instance, reverse=self.reverse,
model=self.model, pk_set=old_ids, using=db,
)
return ManyRelatedManager
|
4d6b1283403d967ea5eddd71a913da66cd2cfd1d0e6fa41ed765dd1ab56b8e44 | from django.db import NotSupportedError
from django.db.models.expressions import Func, Value
from django.db.models.fields import IntegerField
from django.db.models.functions import Coalesce
from django.db.models.lookups import Transform
class BytesToCharFieldConversionMixin:
"""
Convert CharField results from bytes to str.
MySQL returns long data types (bytes) instead of chars when it can't
determine the length of the result string. For example:
LPAD(column1, CHAR_LENGTH(column2), ' ')
returns the LONGTEXT (bytes) instead of VARCHAR.
"""
def convert_value(self, value, expression, connection):
if connection.features.db_functions_convert_bytes_to_str:
if self.output_field.get_internal_type() == 'CharField' and isinstance(value, bytes):
return value.decode()
return super().convert_value(value, expression, connection)
class MySQLSHA2Mixin:
def as_mysql(self, compiler, connection, **extra_content):
return super().as_sql(
compiler,
connection,
template='SHA2(%%(expressions)s, %s)' % self.function[3:],
**extra_content,
)
class OracleHashMixin:
def as_oracle(self, compiler, connection, **extra_context):
return super().as_sql(
compiler,
connection,
template=(
"LOWER(RAWTOHEX(STANDARD_HASH(UTL_I18N.STRING_TO_RAW("
"%(expressions)s, 'AL32UTF8'), '%(function)s')))"
),
**extra_context,
)
class PostgreSQLSHAMixin:
def as_postgresql(self, compiler, connection, **extra_content):
return super().as_sql(
compiler,
connection,
template="ENCODE(DIGEST(%(expressions)s, '%(function)s'), 'hex')",
function=self.function.lower(),
**extra_content,
)
class Chr(Transform):
function = 'CHR'
lookup_name = 'chr'
def as_mysql(self, compiler, connection, **extra_context):
return super().as_sql(
compiler, connection, function='CHAR',
template='%(function)s(%(expressions)s USING utf16)',
**extra_context
)
def as_oracle(self, compiler, connection, **extra_context):
return super().as_sql(
compiler, connection,
template='%(function)s(%(expressions)s USING NCHAR_CS)',
**extra_context
)
def as_sqlite(self, compiler, connection, **extra_context):
return super().as_sql(compiler, connection, function='CHAR', **extra_context)
class ConcatPair(Func):
"""
Concatenate two arguments together. This is used by `Concat` because not
all backend databases support more than two arguments.
"""
function = 'CONCAT'
def as_sqlite(self, compiler, connection, **extra_context):
coalesced = self.coalesce()
return super(ConcatPair, coalesced).as_sql(
compiler, connection, template='%(expressions)s', arg_joiner=' || ',
**extra_context
)
def as_mysql(self, compiler, connection, **extra_context):
# Use CONCAT_WS with an empty separator so that NULLs are ignored.
return super().as_sql(
compiler, connection, function='CONCAT_WS',
template="%(function)s('', %(expressions)s)",
**extra_context
)
def coalesce(self):
# null on either side results in null for expression, wrap with coalesce
c = self.copy()
c.set_source_expressions([
Coalesce(expression, Value('')) for expression in c.get_source_expressions()
])
return c
class Concat(Func):
"""
Concatenate text fields together. Backends that result in an entire
null expression when any arguments are null will wrap each argument in
coalesce functions to ensure a non-null result.
"""
function = None
template = "%(expressions)s"
def __init__(self, *expressions, **extra):
if len(expressions) < 2:
raise ValueError('Concat must take at least two expressions')
paired = self._paired(expressions)
super().__init__(paired, **extra)
def _paired(self, expressions):
# wrap pairs of expressions in successive concat functions
# exp = [a, b, c, d]
# -> ConcatPair(a, ConcatPair(b, ConcatPair(c, d))))
if len(expressions) == 2:
return ConcatPair(*expressions)
return ConcatPair(expressions[0], self._paired(expressions[1:]))
class Left(Func):
function = 'LEFT'
arity = 2
def __init__(self, expression, length, **extra):
"""
expression: the name of a field, or an expression returning a string
length: the number of characters to return from the start of the string
"""
if not hasattr(length, 'resolve_expression'):
if length < 1:
raise ValueError("'length' must be greater than 0.")
super().__init__(expression, length, **extra)
def get_substr(self):
return Substr(self.source_expressions[0], Value(1), self.source_expressions[1])
def as_oracle(self, compiler, connection, **extra_context):
return self.get_substr().as_oracle(compiler, connection, **extra_context)
def as_sqlite(self, compiler, connection, **extra_context):
return self.get_substr().as_sqlite(compiler, connection, **extra_context)
class Length(Transform):
"""Return the number of characters in the expression."""
function = 'LENGTH'
lookup_name = 'length'
output_field = IntegerField()
def as_mysql(self, compiler, connection, **extra_context):
return super().as_sql(compiler, connection, function='CHAR_LENGTH', **extra_context)
class Lower(Transform):
function = 'LOWER'
lookup_name = 'lower'
class LPad(BytesToCharFieldConversionMixin, Func):
function = 'LPAD'
def __init__(self, expression, length, fill_text=Value(' '), **extra):
if not hasattr(length, 'resolve_expression') and length is not None and length < 0:
raise ValueError("'length' must be greater or equal to 0.")
super().__init__(expression, length, fill_text, **extra)
class LTrim(Transform):
function = 'LTRIM'
lookup_name = 'ltrim'
class MD5(OracleHashMixin, Transform):
function = 'MD5'
lookup_name = 'md5'
class Ord(Transform):
function = 'ASCII'
lookup_name = 'ord'
output_field = IntegerField()
def as_mysql(self, compiler, connection, **extra_context):
return super().as_sql(compiler, connection, function='ORD', **extra_context)
def as_sqlite(self, compiler, connection, **extra_context):
return super().as_sql(compiler, connection, function='UNICODE', **extra_context)
class Repeat(BytesToCharFieldConversionMixin, Func):
function = 'REPEAT'
def __init__(self, expression, number, **extra):
if not hasattr(number, 'resolve_expression') and number is not None and number < 0:
raise ValueError("'number' must be greater or equal to 0.")
super().__init__(expression, number, **extra)
def as_oracle(self, compiler, connection, **extra_context):
expression, number = self.source_expressions
length = None if number is None else Length(expression) * number
rpad = RPad(expression, length, expression)
return rpad.as_sql(compiler, connection, **extra_context)
class Replace(Func):
function = 'REPLACE'
def __init__(self, expression, text, replacement=Value(''), **extra):
super().__init__(expression, text, replacement, **extra)
class Reverse(Transform):
function = 'REVERSE'
lookup_name = 'reverse'
def as_oracle(self, compiler, connection, **extra_context):
# REVERSE in Oracle is undocumented and doesn't support multi-byte
# strings. Use a special subquery instead.
return super().as_sql(
compiler, connection,
template=(
'(SELECT LISTAGG(s) WITHIN GROUP (ORDER BY n DESC) FROM '
'(SELECT LEVEL n, SUBSTR(%(expressions)s, LEVEL, 1) s '
'FROM DUAL CONNECT BY LEVEL <= LENGTH(%(expressions)s)) '
'GROUP BY %(expressions)s)'
),
**extra_context
)
class Right(Left):
function = 'RIGHT'
def get_substr(self):
return Substr(self.source_expressions[0], self.source_expressions[1] * Value(-1))
class RPad(LPad):
function = 'RPAD'
class RTrim(Transform):
function = 'RTRIM'
lookup_name = 'rtrim'
class SHA1(OracleHashMixin, PostgreSQLSHAMixin, Transform):
function = 'SHA1'
lookup_name = 'sha1'
class SHA224(MySQLSHA2Mixin, PostgreSQLSHAMixin, Transform):
function = 'SHA224'
lookup_name = 'sha224'
def as_oracle(self, compiler, connection, **extra_context):
raise NotSupportedError('SHA224 is not supported on Oracle.')
class SHA256(MySQLSHA2Mixin, OracleHashMixin, PostgreSQLSHAMixin, Transform):
function = 'SHA256'
lookup_name = 'sha256'
class SHA384(MySQLSHA2Mixin, OracleHashMixin, PostgreSQLSHAMixin, Transform):
function = 'SHA384'
lookup_name = 'sha384'
class SHA512(MySQLSHA2Mixin, OracleHashMixin, PostgreSQLSHAMixin, Transform):
function = 'SHA512'
lookup_name = 'sha512'
class StrIndex(Func):
"""
Return a positive integer corresponding to the 1-indexed position of the
first occurrence of a substring inside another string, or 0 if the
substring is not found.
"""
function = 'INSTR'
arity = 2
output_field = IntegerField()
def as_postgresql(self, compiler, connection, **extra_context):
return super().as_sql(compiler, connection, function='STRPOS', **extra_context)
class Substr(Func):
function = 'SUBSTRING'
def __init__(self, expression, pos, length=None, **extra):
"""
expression: the name of a field, or an expression returning a string
pos: an integer > 0, or an expression returning an integer
length: an optional number of characters to return
"""
if not hasattr(pos, 'resolve_expression'):
if pos < 1:
raise ValueError("'pos' must be greater than 0")
expressions = [expression, pos]
if length is not None:
expressions.append(length)
super().__init__(*expressions, **extra)
def as_sqlite(self, compiler, connection, **extra_context):
return super().as_sql(compiler, connection, function='SUBSTR', **extra_context)
def as_oracle(self, compiler, connection, **extra_context):
return super().as_sql(compiler, connection, function='SUBSTR', **extra_context)
class Trim(Transform):
function = 'TRIM'
lookup_name = 'trim'
class Upper(Transform):
function = 'UPPER'
lookup_name = 'upper'
|
6a170a9183807f74c93a475c21b7e3c663a4ef6691fda85363c7a604d8e20a98 | """Database functions that do comparisons or type conversions."""
from django.db.models.expressions import Func, Value
class Cast(Func):
"""Coerce an expression to a new field type."""
function = 'CAST'
template = '%(function)s(%(expressions)s AS %(db_type)s)'
def __init__(self, expression, output_field):
super().__init__(expression, output_field=output_field)
def as_sql(self, compiler, connection, **extra_context):
extra_context['db_type'] = self.output_field.cast_db_type(connection)
return super().as_sql(compiler, connection, **extra_context)
def as_sqlite(self, compiler, connection, **extra_context):
db_type = self.output_field.db_type(connection)
if db_type in {'datetime', 'time'}:
# Use strftime as datetime/time don't keep fractional seconds.
template = 'strftime(%%s, %(expressions)s)'
sql, params = super().as_sql(compiler, connection, template=template, **extra_context)
format_string = '%H:%M:%f' if db_type == 'time' else '%Y-%m-%d %H:%M:%f'
params.insert(0, format_string)
return sql, params
elif db_type == 'date':
template = 'date(%(expressions)s)'
return super().as_sql(compiler, connection, template=template, **extra_context)
return self.as_sql(compiler, connection, **extra_context)
def as_mysql(self, compiler, connection, **extra_context):
template = None
output_type = self.output_field.get_internal_type()
# MySQL doesn't support explicit cast to float.
if output_type == 'FloatField':
template = '(%(expressions)s + 0.0)'
# MariaDB doesn't support explicit cast to JSON.
elif output_type == 'JSONField' and connection.mysql_is_mariadb:
template = "JSON_EXTRACT(%(expressions)s, '$')"
return self.as_sql(compiler, connection, template=template, **extra_context)
def as_postgresql(self, compiler, connection, **extra_context):
# CAST would be valid too, but the :: shortcut syntax is more readable.
# 'expressions' is wrapped in parentheses in case it's a complex
# expression.
return self.as_sql(compiler, connection, template='(%(expressions)s)::%(db_type)s', **extra_context)
def as_oracle(self, compiler, connection, **extra_context):
if self.output_field.get_internal_type() == 'JSONField':
# Oracle doesn't support explicit cast to JSON.
template = "JSON_QUERY(%(expressions)s, '$')"
return super().as_sql(compiler, connection, template=template, **extra_context)
return self.as_sql(compiler, connection, **extra_context)
class Coalesce(Func):
"""Return, from left to right, the first non-null expression."""
function = 'COALESCE'
def __init__(self, *expressions, **extra):
if len(expressions) < 2:
raise ValueError('Coalesce must take at least two expressions')
super().__init__(*expressions, **extra)
def as_oracle(self, compiler, connection, **extra_context):
# Oracle prohibits mixing TextField (NCLOB) and CharField (NVARCHAR2),
# so convert all fields to NCLOB when that type is expected.
if self.output_field.get_internal_type() == 'TextField':
clone = self.copy()
clone.set_source_expressions([
Func(expression, function='TO_NCLOB') for expression in self.get_source_expressions()
])
return super(Coalesce, clone).as_sql(compiler, connection, **extra_context)
return self.as_sql(compiler, connection, **extra_context)
class Greatest(Func):
"""
Return the maximum expression.
If any expression is null the return value is database-specific:
On PostgreSQL, the maximum not-null expression is returned.
On MySQL, Oracle, and SQLite, if any expression is null, null is returned.
"""
function = 'GREATEST'
def __init__(self, *expressions, **extra):
if len(expressions) < 2:
raise ValueError('Greatest must take at least two expressions')
super().__init__(*expressions, **extra)
def as_sqlite(self, compiler, connection, **extra_context):
"""Use the MAX function on SQLite."""
return super().as_sqlite(compiler, connection, function='MAX', **extra_context)
class Least(Func):
"""
Return the minimum expression.
If any expression is null the return value is database-specific:
On PostgreSQL, return the minimum not-null expression.
On MySQL, Oracle, and SQLite, if any expression is null, return null.
"""
function = 'LEAST'
def __init__(self, *expressions, **extra):
if len(expressions) < 2:
raise ValueError('Least must take at least two expressions')
super().__init__(*expressions, **extra)
def as_sqlite(self, compiler, connection, **extra_context):
"""Use the MIN function on SQLite."""
return super().as_sqlite(compiler, connection, function='MIN', **extra_context)
class NullIf(Func):
function = 'NULLIF'
arity = 2
def as_oracle(self, compiler, connection, **extra_context):
expression1 = self.get_source_expressions()[0]
if isinstance(expression1, Value) and expression1.value is None:
raise ValueError('Oracle does not allow Value(None) for expression1.')
return super().as_sql(compiler, connection, **extra_context)
|
0ede1c6283b53827aaf5cc015a09f6b94390445a8f042d325014f80fcf0da2e1 | """
Create SQL statements for QuerySets.
The code in here encapsulates all of the SQL construction so that QuerySets
themselves do not have to (and could be backed by things other than SQL
databases). The abstraction barrier only works one way: this module has to know
all about the internals of models in order to get the information it needs.
"""
import copy
import difflib
import functools
import inspect
import sys
import warnings
from collections import Counter, namedtuple
from collections.abc import Iterator, Mapping
from itertools import chain, count, product
from string import ascii_uppercase
from django.core.exceptions import (
EmptyResultSet, FieldDoesNotExist, FieldError,
)
from django.db import DEFAULT_DB_ALIAS, NotSupportedError, connections
from django.db.models.aggregates import Count
from django.db.models.constants import LOOKUP_SEP
from django.db.models.expressions import BaseExpression, Col, F, OuterRef, Ref
from django.db.models.fields import Field
from django.db.models.fields.related_lookups import MultiColSource
from django.db.models.lookups import Lookup
from django.db.models.query_utils import (
Q, check_rel_lookup_compatibility, refs_expression,
)
from django.db.models.sql.constants import INNER, LOUTER, ORDER_DIR, SINGLE
from django.db.models.sql.datastructures import (
BaseTable, Empty, Join, MultiJoin,
)
from django.db.models.sql.where import (
AND, OR, ExtraWhere, NothingNode, WhereNode,
)
from django.utils.deprecation import RemovedInDjango40Warning
from django.utils.functional import cached_property
from django.utils.tree import Node
__all__ = ['Query', 'RawQuery']
def get_field_names_from_opts(opts):
return set(chain.from_iterable(
(f.name, f.attname) if f.concrete else (f.name,)
for f in opts.get_fields()
))
def get_children_from_q(q):
for child in q.children:
if isinstance(child, Node):
yield from get_children_from_q(child)
else:
yield child
JoinInfo = namedtuple(
'JoinInfo',
('final_field', 'targets', 'opts', 'joins', 'path', 'transform_function')
)
class RawQuery:
"""A single raw SQL query."""
def __init__(self, sql, using, params=None):
self.params = params or ()
self.sql = sql
self.using = using
self.cursor = None
# Mirror some properties of a normal query so that
# the compiler can be used to process results.
self.low_mark, self.high_mark = 0, None # Used for offset/limit
self.extra_select = {}
self.annotation_select = {}
def chain(self, using):
return self.clone(using)
def clone(self, using):
return RawQuery(self.sql, using, params=self.params)
def get_columns(self):
if self.cursor is None:
self._execute_query()
converter = connections[self.using].introspection.identifier_converter
return [converter(column_meta[0])
for column_meta in self.cursor.description]
def __iter__(self):
# Always execute a new query for a new iterator.
# This could be optimized with a cache at the expense of RAM.
self._execute_query()
if not connections[self.using].features.can_use_chunked_reads:
# If the database can't use chunked reads we need to make sure we
# evaluate the entire query up front.
result = list(self.cursor)
else:
result = self.cursor
return iter(result)
def __repr__(self):
return "<%s: %s>" % (self.__class__.__name__, self)
@property
def params_type(self):
return dict if isinstance(self.params, Mapping) else tuple
def __str__(self):
return self.sql % self.params_type(self.params)
def _execute_query(self):
connection = connections[self.using]
# Adapt parameters to the database, as much as possible considering
# that the target type isn't known. See #17755.
params_type = self.params_type
adapter = connection.ops.adapt_unknown_value
if params_type is tuple:
params = tuple(adapter(val) for val in self.params)
elif params_type is dict:
params = {key: adapter(val) for key, val in self.params.items()}
else:
raise RuntimeError("Unexpected params type: %s" % params_type)
self.cursor = connection.cursor()
self.cursor.execute(self.sql, params)
class Query(BaseExpression):
"""A single SQL query."""
alias_prefix = 'T'
subq_aliases = frozenset([alias_prefix])
compiler = 'SQLCompiler'
def __init__(self, model, where=WhereNode, alias_cols=True):
self.model = model
self.alias_refcount = {}
# alias_map is the most important data structure regarding joins.
# It's used for recording which joins exist in the query and what
# types they are. The key is the alias of the joined table (possibly
# the table name) and the value is a Join-like object (see
# sql.datastructures.Join for more information).
self.alias_map = {}
# Whether to provide alias to columns during reference resolving.
self.alias_cols = alias_cols
# Sometimes the query contains references to aliases in outer queries (as
# a result of split_exclude). Correct alias quoting needs to know these
# aliases too.
# Map external tables to whether they are aliased.
self.external_aliases = {}
self.table_map = {} # Maps table names to list of aliases.
self.default_cols = True
self.default_ordering = True
self.standard_ordering = True
self.used_aliases = set()
self.filter_is_sticky = False
self.subquery = False
# SQL-related attributes
# Select and related select clauses are expressions to use in the
# SELECT clause of the query.
# The select is used for cases where we want to set up the select
# clause to contain other than default fields (values(), subqueries...)
# Note that annotations go to annotations dictionary.
self.select = ()
self.where = where()
self.where_class = where
# The group_by attribute can have one of the following forms:
# - None: no group by at all in the query
# - A tuple of expressions: group by (at least) those expressions.
# String refs are also allowed for now.
# - True: group by all select fields of the model
# See compiler.get_group_by() for details.
self.group_by = None
self.order_by = ()
self.low_mark, self.high_mark = 0, None # Used for offset/limit
self.distinct = False
self.distinct_fields = ()
self.select_for_update = False
self.select_for_update_nowait = False
self.select_for_update_skip_locked = False
self.select_for_update_of = ()
self.select_related = False
# Arbitrary limit for select_related to prevents infinite recursion.
self.max_depth = 5
# Holds the selects defined by a call to values() or values_list()
# excluding annotation_select and extra_select.
self.values_select = ()
# SQL annotation-related attributes
self.annotations = {} # Maps alias -> Annotation Expression
self.annotation_select_mask = None
self._annotation_select_cache = None
# Set combination attributes
self.combinator = None
self.combinator_all = False
self.combined_queries = ()
# These are for extensions. The contents are more or less appended
# verbatim to the appropriate clause.
self.extra = {} # Maps col_alias -> (col_sql, params).
self.extra_select_mask = None
self._extra_select_cache = None
self.extra_tables = ()
self.extra_order_by = ()
# A tuple that is a set of model field names and either True, if these
# are the fields to defer, or False if these are the only fields to
# load.
self.deferred_loading = (frozenset(), True)
self._filtered_relations = {}
self.explain_query = False
self.explain_format = None
self.explain_options = {}
@property
def output_field(self):
if len(self.select) == 1:
select = self.select[0]
return getattr(select, 'target', None) or select.field
elif len(self.annotation_select) == 1:
return next(iter(self.annotation_select.values())).output_field
@property
def has_select_fields(self):
return bool(self.select or self.annotation_select_mask or self.extra_select_mask)
@cached_property
def base_table(self):
for alias in self.alias_map:
return alias
def __str__(self):
"""
Return the query as a string of SQL with the parameter values
substituted in (use sql_with_params() to see the unsubstituted string).
Parameter values won't necessarily be quoted correctly, since that is
done by the database interface at execution time.
"""
sql, params = self.sql_with_params()
return sql % params
def sql_with_params(self):
"""
Return the query as an SQL string and the parameters that will be
substituted into the query.
"""
return self.get_compiler(DEFAULT_DB_ALIAS).as_sql()
def __deepcopy__(self, memo):
"""Limit the amount of work when a Query is deepcopied."""
result = self.clone()
memo[id(self)] = result
return result
def get_compiler(self, using=None, connection=None):
if using is None and connection is None:
raise ValueError("Need either using or connection")
if using:
connection = connections[using]
return connection.ops.compiler(self.compiler)(self, connection, using)
def get_meta(self):
"""
Return the Options instance (the model._meta) from which to start
processing. Normally, this is self.model._meta, but it can be changed
by subclasses.
"""
return self.model._meta
def clone(self):
"""
Return a copy of the current Query. A lightweight alternative to
to deepcopy().
"""
obj = Empty()
obj.__class__ = self.__class__
# Copy references to everything.
obj.__dict__ = self.__dict__.copy()
# Clone attributes that can't use shallow copy.
obj.alias_refcount = self.alias_refcount.copy()
obj.alias_map = self.alias_map.copy()
obj.external_aliases = self.external_aliases.copy()
obj.table_map = self.table_map.copy()
obj.where = self.where.clone()
obj.annotations = self.annotations.copy()
if self.annotation_select_mask is None:
obj.annotation_select_mask = None
else:
obj.annotation_select_mask = self.annotation_select_mask.copy()
# _annotation_select_cache cannot be copied, as doing so breaks the
# (necessary) state in which both annotations and
# _annotation_select_cache point to the same underlying objects.
# It will get re-populated in the cloned queryset the next time it's
# used.
obj._annotation_select_cache = None
obj.extra = self.extra.copy()
if self.extra_select_mask is None:
obj.extra_select_mask = None
else:
obj.extra_select_mask = self.extra_select_mask.copy()
if self._extra_select_cache is None:
obj._extra_select_cache = None
else:
obj._extra_select_cache = self._extra_select_cache.copy()
if self.select_related is not False:
# Use deepcopy because select_related stores fields in nested
# dicts.
obj.select_related = copy.deepcopy(obj.select_related)
if 'subq_aliases' in self.__dict__:
obj.subq_aliases = self.subq_aliases.copy()
obj.used_aliases = self.used_aliases.copy()
obj._filtered_relations = self._filtered_relations.copy()
# Clear the cached_property
try:
del obj.base_table
except AttributeError:
pass
return obj
def chain(self, klass=None):
"""
Return a copy of the current Query that's ready for another operation.
The klass argument changes the type of the Query, e.g. UpdateQuery.
"""
obj = self.clone()
if klass and obj.__class__ != klass:
obj.__class__ = klass
if not obj.filter_is_sticky:
obj.used_aliases = set()
obj.filter_is_sticky = False
if hasattr(obj, '_setup_query'):
obj._setup_query()
return obj
def relabeled_clone(self, change_map):
clone = self.clone()
clone.change_aliases(change_map)
return clone
def _get_col(self, target, field, alias):
if not self.alias_cols:
alias = None
return target.get_col(alias, field)
def rewrite_cols(self, annotation, col_cnt):
# We must make sure the inner query has the referred columns in it.
# If we are aggregating over an annotation, then Django uses Ref()
# instances to note this. However, if we are annotating over a column
# of a related model, then it might be that column isn't part of the
# SELECT clause of the inner query, and we must manually make sure
# the column is selected. An example case is:
# .aggregate(Sum('author__awards'))
# Resolving this expression results in a join to author, but there
# is no guarantee the awards column of author is in the select clause
# of the query. Thus we must manually add the column to the inner
# query.
orig_exprs = annotation.get_source_expressions()
new_exprs = []
for expr in orig_exprs:
# FIXME: These conditions are fairly arbitrary. Identify a better
# method of having expressions decide which code path they should
# take.
if isinstance(expr, Ref):
# Its already a Ref to subquery (see resolve_ref() for
# details)
new_exprs.append(expr)
elif isinstance(expr, (WhereNode, Lookup)):
# Decompose the subexpressions further. The code here is
# copied from the else clause, but this condition must appear
# before the contains_aggregate/is_summary condition below.
new_expr, col_cnt = self.rewrite_cols(expr, col_cnt)
new_exprs.append(new_expr)
else:
# Reuse aliases of expressions already selected in subquery.
for col_alias, selected_annotation in self.annotation_select.items():
if selected_annotation == expr:
new_expr = Ref(col_alias, expr)
break
else:
# An expression that is not selected the subquery.
if isinstance(expr, Col) or (expr.contains_aggregate and not expr.is_summary):
# Reference column or another aggregate. Select it
# under a non-conflicting alias.
col_cnt += 1
col_alias = '__col%d' % col_cnt
self.annotations[col_alias] = expr
self.append_annotation_mask([col_alias])
new_expr = Ref(col_alias, expr)
else:
# Some other expression not referencing database values
# directly. Its subexpression might contain Cols.
new_expr, col_cnt = self.rewrite_cols(expr, col_cnt)
new_exprs.append(new_expr)
annotation.set_source_expressions(new_exprs)
return annotation, col_cnt
def get_aggregation(self, using, added_aggregate_names):
"""
Return the dictionary with the values of the existing aggregations.
"""
if not self.annotation_select:
return {}
existing_annotations = [
annotation for alias, annotation
in self.annotations.items()
if alias not in added_aggregate_names
]
# Decide if we need to use a subquery.
#
# Existing annotations would cause incorrect results as get_aggregation()
# must produce just one result and thus must not use GROUP BY. But we
# aren't smart enough to remove the existing annotations from the
# query, so those would force us to use GROUP BY.
#
# If the query has limit or distinct, or uses set operations, then
# those operations must be done in a subquery so that the query
# aggregates on the limit and/or distinct results instead of applying
# the distinct and limit after the aggregation.
if (isinstance(self.group_by, tuple) or self.is_sliced or existing_annotations or
self.distinct or self.combinator):
from django.db.models.sql.subqueries import AggregateQuery
outer_query = AggregateQuery(self.model)
inner_query = self.clone()
inner_query.select_for_update = False
inner_query.select_related = False
inner_query.set_annotation_mask(self.annotation_select)
if not self.is_sliced and not self.distinct_fields:
# Queries with distinct_fields need ordering and when a limit
# is applied we must take the slice from the ordered query.
# Otherwise no need for ordering.
inner_query.clear_ordering(True)
if not inner_query.distinct:
# If the inner query uses default select and it has some
# aggregate annotations, then we must make sure the inner
# query is grouped by the main model's primary key. However,
# clearing the select clause can alter results if distinct is
# used.
has_existing_aggregate_annotations = any(
annotation for annotation in existing_annotations
if getattr(annotation, 'contains_aggregate', True)
)
if inner_query.default_cols and has_existing_aggregate_annotations:
inner_query.group_by = (self.model._meta.pk.get_col(inner_query.get_initial_alias()),)
inner_query.default_cols = False
relabels = {t: 'subquery' for t in inner_query.alias_map}
relabels[None] = 'subquery'
# Remove any aggregates marked for reduction from the subquery
# and move them to the outer AggregateQuery.
col_cnt = 0
for alias, expression in list(inner_query.annotation_select.items()):
annotation_select_mask = inner_query.annotation_select_mask
if expression.is_summary:
expression, col_cnt = inner_query.rewrite_cols(expression, col_cnt)
outer_query.annotations[alias] = expression.relabeled_clone(relabels)
del inner_query.annotations[alias]
annotation_select_mask.remove(alias)
# Make sure the annotation_select wont use cached results.
inner_query.set_annotation_mask(inner_query.annotation_select_mask)
if inner_query.select == () and not inner_query.default_cols and not inner_query.annotation_select_mask:
# In case of Model.objects[0:3].count(), there would be no
# field selected in the inner query, yet we must use a subquery.
# So, make sure at least one field is selected.
inner_query.select = (self.model._meta.pk.get_col(inner_query.get_initial_alias()),)
try:
outer_query.add_subquery(inner_query, using)
except EmptyResultSet:
return {
alias: None
for alias in outer_query.annotation_select
}
else:
outer_query = self
self.select = ()
self.default_cols = False
self.extra = {}
outer_query.clear_ordering(True)
outer_query.clear_limits()
outer_query.select_for_update = False
outer_query.select_related = False
compiler = outer_query.get_compiler(using)
result = compiler.execute_sql(SINGLE)
if result is None:
result = [None] * len(outer_query.annotation_select)
converters = compiler.get_converters(outer_query.annotation_select.values())
result = next(compiler.apply_converters((result,), converters))
return dict(zip(outer_query.annotation_select, result))
def get_count(self, using):
"""
Perform a COUNT() query using the current filter constraints.
"""
obj = self.clone()
obj.add_annotation(Count('*'), alias='__count', is_summary=True)
number = obj.get_aggregation(using, ['__count'])['__count']
if number is None:
number = 0
return number
def has_filters(self):
return self.where
def has_results(self, using):
q = self.clone()
if not q.distinct:
if q.group_by is True:
q.add_fields((f.attname for f in self.model._meta.concrete_fields), False)
# Disable GROUP BY aliases to avoid orphaning references to the
# SELECT clause which is about to be cleared.
q.set_group_by(allow_aliases=False)
q.clear_select_clause()
q.clear_ordering(True)
q.set_limits(high=1)
compiler = q.get_compiler(using=using)
return compiler.has_results()
def explain(self, using, format=None, **options):
q = self.clone()
q.explain_query = True
q.explain_format = format
q.explain_options = options
compiler = q.get_compiler(using=using)
return '\n'.join(compiler.explain_query())
def combine(self, rhs, connector):
"""
Merge the 'rhs' query into the current one (with any 'rhs' effects
being applied *after* (that is, "to the right of") anything in the
current query. 'rhs' is not modified during a call to this function.
The 'connector' parameter describes how to connect filters from the
'rhs' query.
"""
assert self.model == rhs.model, \
"Cannot combine queries on two different base models."
assert not self.is_sliced, \
"Cannot combine queries once a slice has been taken."
assert self.distinct == rhs.distinct, \
"Cannot combine a unique query with a non-unique query."
assert self.distinct_fields == rhs.distinct_fields, \
"Cannot combine queries with different distinct fields."
# Work out how to relabel the rhs aliases, if necessary.
change_map = {}
conjunction = (connector == AND)
# Determine which existing joins can be reused. When combining the
# query with AND we must recreate all joins for m2m filters. When
# combining with OR we can reuse joins. The reason is that in AND
# case a single row can't fulfill a condition like:
# revrel__col=1 & revrel__col=2
# But, there might be two different related rows matching this
# condition. In OR case a single True is enough, so single row is
# enough, too.
#
# Note that we will be creating duplicate joins for non-m2m joins in
# the AND case. The results will be correct but this creates too many
# joins. This is something that could be fixed later on.
reuse = set() if conjunction else set(self.alias_map)
# Base table must be present in the query - this is the same
# table on both sides.
self.get_initial_alias()
joinpromoter = JoinPromoter(connector, 2, False)
joinpromoter.add_votes(
j for j in self.alias_map if self.alias_map[j].join_type == INNER)
rhs_votes = set()
# Now, add the joins from rhs query into the new query (skipping base
# table).
rhs_tables = list(rhs.alias_map)[1:]
for alias in rhs_tables:
join = rhs.alias_map[alias]
# If the left side of the join was already relabeled, use the
# updated alias.
join = join.relabeled_clone(change_map)
new_alias = self.join(join, reuse=reuse)
if join.join_type == INNER:
rhs_votes.add(new_alias)
# We can't reuse the same join again in the query. If we have two
# distinct joins for the same connection in rhs query, then the
# combined query must have two joins, too.
reuse.discard(new_alias)
if alias != new_alias:
change_map[alias] = new_alias
if not rhs.alias_refcount[alias]:
# The alias was unused in the rhs query. Unref it so that it
# will be unused in the new query, too. We have to add and
# unref the alias so that join promotion has information of
# the join type for the unused alias.
self.unref_alias(new_alias)
joinpromoter.add_votes(rhs_votes)
joinpromoter.update_join_types(self)
# Now relabel a copy of the rhs where-clause and add it to the current
# one.
w = rhs.where.clone()
w.relabel_aliases(change_map)
self.where.add(w, connector)
# Selection columns and extra extensions are those provided by 'rhs'.
if rhs.select:
self.set_select([col.relabeled_clone(change_map) for col in rhs.select])
else:
self.select = ()
if connector == OR:
# It would be nice to be able to handle this, but the queries don't
# really make sense (or return consistent value sets). Not worth
# the extra complexity when you can write a real query instead.
if self.extra and rhs.extra:
raise ValueError("When merging querysets using 'or', you cannot have extra(select=...) on both sides.")
self.extra.update(rhs.extra)
extra_select_mask = set()
if self.extra_select_mask is not None:
extra_select_mask.update(self.extra_select_mask)
if rhs.extra_select_mask is not None:
extra_select_mask.update(rhs.extra_select_mask)
if extra_select_mask:
self.set_extra_mask(extra_select_mask)
self.extra_tables += rhs.extra_tables
# Ordering uses the 'rhs' ordering, unless it has none, in which case
# the current ordering is used.
self.order_by = rhs.order_by or self.order_by
self.extra_order_by = rhs.extra_order_by or self.extra_order_by
def deferred_to_data(self, target, callback):
"""
Convert the self.deferred_loading data structure to an alternate data
structure, describing the field that *will* be loaded. This is used to
compute the columns to select from the database and also by the
QuerySet class to work out which fields are being initialized on each
model. Models that have all their fields included aren't mentioned in
the result, only those that have field restrictions in place.
The "target" parameter is the instance that is populated (in place).
The "callback" is a function that is called whenever a (model, field)
pair need to be added to "target". It accepts three parameters:
"target", and the model and list of fields being added for that model.
"""
field_names, defer = self.deferred_loading
if not field_names:
return
orig_opts = self.get_meta()
seen = {}
must_include = {orig_opts.concrete_model: {orig_opts.pk}}
for field_name in field_names:
parts = field_name.split(LOOKUP_SEP)
cur_model = self.model._meta.concrete_model
opts = orig_opts
for name in parts[:-1]:
old_model = cur_model
if name in self._filtered_relations:
name = self._filtered_relations[name].relation_name
source = opts.get_field(name)
if is_reverse_o2o(source):
cur_model = source.related_model
else:
cur_model = source.remote_field.model
opts = cur_model._meta
# Even if we're "just passing through" this model, we must add
# both the current model's pk and the related reference field
# (if it's not a reverse relation) to the things we select.
if not is_reverse_o2o(source):
must_include[old_model].add(source)
add_to_dict(must_include, cur_model, opts.pk)
field = opts.get_field(parts[-1])
is_reverse_object = field.auto_created and not field.concrete
model = field.related_model if is_reverse_object else field.model
model = model._meta.concrete_model
if model == opts.model:
model = cur_model
if not is_reverse_o2o(field):
add_to_dict(seen, model, field)
if defer:
# We need to load all fields for each model, except those that
# appear in "seen" (for all models that appear in "seen"). The only
# slight complexity here is handling fields that exist on parent
# models.
workset = {}
for model, values in seen.items():
for field in model._meta.local_fields:
if field not in values:
m = field.model._meta.concrete_model
add_to_dict(workset, m, field)
for model, values in must_include.items():
# If we haven't included a model in workset, we don't add the
# corresponding must_include fields for that model, since an
# empty set means "include all fields". That's why there's no
# "else" branch here.
if model in workset:
workset[model].update(values)
for model, values in workset.items():
callback(target, model, values)
else:
for model, values in must_include.items():
if model in seen:
seen[model].update(values)
else:
# As we've passed through this model, but not explicitly
# included any fields, we have to make sure it's mentioned
# so that only the "must include" fields are pulled in.
seen[model] = values
# Now ensure that every model in the inheritance chain is mentioned
# in the parent list. Again, it must be mentioned to ensure that
# only "must include" fields are pulled in.
for model in orig_opts.get_parent_list():
seen.setdefault(model, set())
for model, values in seen.items():
callback(target, model, values)
def table_alias(self, table_name, create=False, filtered_relation=None):
"""
Return a table alias for the given table_name and whether this is a
new alias or not.
If 'create' is true, a new alias is always created. Otherwise, the
most recently created alias for the table (if one exists) is reused.
"""
alias_list = self.table_map.get(table_name)
if not create and alias_list:
alias = alias_list[0]
self.alias_refcount[alias] += 1
return alias, False
# Create a new alias for this table.
if alias_list:
alias = '%s%d' % (self.alias_prefix, len(self.alias_map) + 1)
alias_list.append(alias)
else:
# The first occurrence of a table uses the table name directly.
alias = filtered_relation.alias if filtered_relation is not None else table_name
self.table_map[table_name] = [alias]
self.alias_refcount[alias] = 1
return alias, True
def ref_alias(self, alias):
"""Increases the reference count for this alias."""
self.alias_refcount[alias] += 1
def unref_alias(self, alias, amount=1):
"""Decreases the reference count for this alias."""
self.alias_refcount[alias] -= amount
def promote_joins(self, aliases):
"""
Promote recursively the join type of given aliases and its children to
an outer join. If 'unconditional' is False, only promote the join if
it is nullable or the parent join is an outer join.
The children promotion is done to avoid join chains that contain a LOUTER
b INNER c. So, if we have currently a INNER b INNER c and a->b is promoted,
then we must also promote b->c automatically, or otherwise the promotion
of a->b doesn't actually change anything in the query results.
"""
aliases = list(aliases)
while aliases:
alias = aliases.pop(0)
if self.alias_map[alias].join_type is None:
# This is the base table (first FROM entry) - this table
# isn't really joined at all in the query, so we should not
# alter its join type.
continue
# Only the first alias (skipped above) should have None join_type
assert self.alias_map[alias].join_type is not None
parent_alias = self.alias_map[alias].parent_alias
parent_louter = parent_alias and self.alias_map[parent_alias].join_type == LOUTER
already_louter = self.alias_map[alias].join_type == LOUTER
if ((self.alias_map[alias].nullable or parent_louter) and
not already_louter):
self.alias_map[alias] = self.alias_map[alias].promote()
# Join type of 'alias' changed, so re-examine all aliases that
# refer to this one.
aliases.extend(
join for join in self.alias_map
if self.alias_map[join].parent_alias == alias and join not in aliases
)
def demote_joins(self, aliases):
"""
Change join type from LOUTER to INNER for all joins in aliases.
Similarly to promote_joins(), this method must ensure no join chains
containing first an outer, then an inner join are generated. If we
are demoting b->c join in chain a LOUTER b LOUTER c then we must
demote a->b automatically, or otherwise the demotion of b->c doesn't
actually change anything in the query results. .
"""
aliases = list(aliases)
while aliases:
alias = aliases.pop(0)
if self.alias_map[alias].join_type == LOUTER:
self.alias_map[alias] = self.alias_map[alias].demote()
parent_alias = self.alias_map[alias].parent_alias
if self.alias_map[parent_alias].join_type == INNER:
aliases.append(parent_alias)
def reset_refcounts(self, to_counts):
"""
Reset reference counts for aliases so that they match the value passed
in `to_counts`.
"""
for alias, cur_refcount in self.alias_refcount.copy().items():
unref_amount = cur_refcount - to_counts.get(alias, 0)
self.unref_alias(alias, unref_amount)
def change_aliases(self, change_map):
"""
Change the aliases in change_map (which maps old-alias -> new-alias),
relabelling any references to them in select columns and the where
clause.
"""
assert set(change_map).isdisjoint(change_map.values())
# 1. Update references in "select" (normal columns plus aliases),
# "group by" and "where".
self.where.relabel_aliases(change_map)
if isinstance(self.group_by, tuple):
self.group_by = tuple([col.relabeled_clone(change_map) for col in self.group_by])
self.select = tuple([col.relabeled_clone(change_map) for col in self.select])
self.annotations = self.annotations and {
key: col.relabeled_clone(change_map) for key, col in self.annotations.items()
}
# 2. Rename the alias in the internal table/alias datastructures.
for old_alias, new_alias in change_map.items():
if old_alias not in self.alias_map:
continue
alias_data = self.alias_map[old_alias].relabeled_clone(change_map)
self.alias_map[new_alias] = alias_data
self.alias_refcount[new_alias] = self.alias_refcount[old_alias]
del self.alias_refcount[old_alias]
del self.alias_map[old_alias]
table_aliases = self.table_map[alias_data.table_name]
for pos, alias in enumerate(table_aliases):
if alias == old_alias:
table_aliases[pos] = new_alias
break
self.external_aliases = {
# Table is aliased or it's being changed and thus is aliased.
change_map.get(alias, alias): (aliased or alias in change_map)
for alias, aliased in self.external_aliases.items()
}
def bump_prefix(self, outer_query):
"""
Change the alias prefix to the next letter in the alphabet in a way
that the outer query's aliases and this query's aliases will not
conflict. Even tables that previously had no alias will get an alias
after this call.
"""
def prefix_gen():
"""
Generate a sequence of characters in alphabetical order:
-> 'A', 'B', 'C', ...
When the alphabet is finished, the sequence will continue with the
Cartesian product:
-> 'AA', 'AB', 'AC', ...
"""
alphabet = ascii_uppercase
prefix = chr(ord(self.alias_prefix) + 1)
yield prefix
for n in count(1):
seq = alphabet[alphabet.index(prefix):] if prefix else alphabet
for s in product(seq, repeat=n):
yield ''.join(s)
prefix = None
if self.alias_prefix != outer_query.alias_prefix:
# No clashes between self and outer query should be possible.
return
# Explicitly avoid infinite loop. The constant divider is based on how
# much depth recursive subquery references add to the stack. This value
# might need to be adjusted when adding or removing function calls from
# the code path in charge of performing these operations.
local_recursion_limit = sys.getrecursionlimit() // 16
for pos, prefix in enumerate(prefix_gen()):
if prefix not in self.subq_aliases:
self.alias_prefix = prefix
break
if pos > local_recursion_limit:
raise RecursionError(
'Maximum recursion depth exceeded: too many subqueries.'
)
self.subq_aliases = self.subq_aliases.union([self.alias_prefix])
outer_query.subq_aliases = outer_query.subq_aliases.union(self.subq_aliases)
self.change_aliases({
alias: '%s%d' % (self.alias_prefix, pos)
for pos, alias in enumerate(self.alias_map)
})
def get_initial_alias(self):
"""
Return the first alias for this query, after increasing its reference
count.
"""
if self.alias_map:
alias = self.base_table
self.ref_alias(alias)
else:
alias = self.join(BaseTable(self.get_meta().db_table, None))
return alias
def count_active_tables(self):
"""
Return the number of tables in this query with a non-zero reference
count. After execution, the reference counts are zeroed, so tables
added in compiler will not be seen by this method.
"""
return len([1 for count in self.alias_refcount.values() if count])
def join(self, join, reuse=None, reuse_with_filtered_relation=False):
"""
Return an alias for the 'join', either reusing an existing alias for
that join or creating a new one. 'join' is either a
sql.datastructures.BaseTable or Join.
The 'reuse' parameter can be either None which means all joins are
reusable, or it can be a set containing the aliases that can be reused.
The 'reuse_with_filtered_relation' parameter is used when computing
FilteredRelation instances.
A join is always created as LOUTER if the lhs alias is LOUTER to make
sure chains like t1 LOUTER t2 INNER t3 aren't generated. All new
joins are created as LOUTER if the join is nullable.
"""
if reuse_with_filtered_relation and reuse:
reuse_aliases = [
a for a, j in self.alias_map.items()
if a in reuse and j.equals(join, with_filtered_relation=False)
]
else:
reuse_aliases = [
a for a, j in self.alias_map.items()
if (reuse is None or a in reuse) and j == join
]
if reuse_aliases:
if join.table_alias in reuse_aliases:
reuse_alias = join.table_alias
else:
# Reuse the most recent alias of the joined table
# (a many-to-many relation may be joined multiple times).
reuse_alias = reuse_aliases[-1]
self.ref_alias(reuse_alias)
return reuse_alias
# No reuse is possible, so we need a new alias.
alias, _ = self.table_alias(join.table_name, create=True, filtered_relation=join.filtered_relation)
if join.join_type:
if self.alias_map[join.parent_alias].join_type == LOUTER or join.nullable:
join_type = LOUTER
else:
join_type = INNER
join.join_type = join_type
join.table_alias = alias
self.alias_map[alias] = join
return alias
def join_parent_model(self, opts, model, alias, seen):
"""
Make sure the given 'model' is joined in the query. If 'model' isn't
a parent of 'opts' or if it is None this method is a no-op.
The 'alias' is the root alias for starting the join, 'seen' is a dict
of model -> alias of existing joins. It must also contain a mapping
of None -> some alias. This will be returned in the no-op case.
"""
if model in seen:
return seen[model]
chain = opts.get_base_chain(model)
if not chain:
return alias
curr_opts = opts
for int_model in chain:
if int_model in seen:
curr_opts = int_model._meta
alias = seen[int_model]
continue
# Proxy model have elements in base chain
# with no parents, assign the new options
# object and skip to the next base in that
# case
if not curr_opts.parents[int_model]:
curr_opts = int_model._meta
continue
link_field = curr_opts.get_ancestor_link(int_model)
join_info = self.setup_joins([link_field.name], curr_opts, alias)
curr_opts = int_model._meta
alias = seen[int_model] = join_info.joins[-1]
return alias or seen[None]
def add_annotation(self, annotation, alias, is_summary=False):
"""Add a single annotation expression to the Query."""
annotation = annotation.resolve_expression(self, allow_joins=True, reuse=None,
summarize=is_summary)
self.append_annotation_mask([alias])
self.annotations[alias] = annotation
def resolve_expression(self, query, *args, **kwargs):
clone = self.clone()
# Subqueries need to use a different set of aliases than the outer query.
clone.bump_prefix(query)
clone.subquery = True
# It's safe to drop ordering if the queryset isn't using slicing,
# distinct(*fields) or select_for_update().
if (self.low_mark == 0 and self.high_mark is None and
not self.distinct_fields and
not self.select_for_update):
clone.clear_ordering(True)
clone.where.resolve_expression(query, *args, **kwargs)
for key, value in clone.annotations.items():
resolved = value.resolve_expression(query, *args, **kwargs)
if hasattr(resolved, 'external_aliases'):
resolved.external_aliases.update(clone.external_aliases)
clone.annotations[key] = resolved
# Outer query's aliases are considered external.
for alias, table in query.alias_map.items():
clone.external_aliases[alias] = (
(isinstance(table, Join) and table.join_field.related_model._meta.db_table != alias) or
(isinstance(table, BaseTable) and table.table_name != table.table_alias)
)
return clone
def get_external_cols(self):
exprs = chain(self.annotations.values(), self.where.children)
return [
col for col in self._gen_cols(exprs)
if col.alias in self.external_aliases
]
def as_sql(self, compiler, connection):
sql, params = self.get_compiler(connection=connection).as_sql()
if self.subquery:
sql = '(%s)' % sql
return sql, params
def resolve_lookup_value(self, value, can_reuse, allow_joins):
if hasattr(value, 'resolve_expression'):
value = value.resolve_expression(
self, reuse=can_reuse, allow_joins=allow_joins,
)
elif isinstance(value, (list, tuple)):
# The items of the iterable may be expressions and therefore need
# to be resolved independently.
return type(value)(
self.resolve_lookup_value(sub_value, can_reuse, allow_joins)
for sub_value in value
)
return value
def solve_lookup_type(self, lookup):
"""
Solve the lookup type from the lookup (e.g.: 'foobar__id__icontains').
"""
lookup_splitted = lookup.split(LOOKUP_SEP)
if self.annotations:
expression, expression_lookups = refs_expression(lookup_splitted, self.annotations)
if expression:
return expression_lookups, (), expression
_, field, _, lookup_parts = self.names_to_path(lookup_splitted, self.get_meta())
field_parts = lookup_splitted[0:len(lookup_splitted) - len(lookup_parts)]
if len(lookup_parts) > 1 and not field_parts:
raise FieldError(
'Invalid lookup "%s" for model %s".' %
(lookup, self.get_meta().model.__name__)
)
return lookup_parts, field_parts, False
def check_query_object_type(self, value, opts, field):
"""
Check whether the object passed while querying is of the correct type.
If not, raise a ValueError specifying the wrong object.
"""
if hasattr(value, '_meta'):
if not check_rel_lookup_compatibility(value._meta.model, opts, field):
raise ValueError(
'Cannot query "%s": Must be "%s" instance.' %
(value, opts.object_name))
def check_related_objects(self, field, value, opts):
"""Check the type of object passed to query relations."""
if field.is_relation:
# Check that the field and the queryset use the same model in a
# query like .filter(author=Author.objects.all()). For example, the
# opts would be Author's (from the author field) and value.model
# would be Author.objects.all() queryset's .model (Author also).
# The field is the related field on the lhs side.
if (isinstance(value, Query) and not value.has_select_fields and
not check_rel_lookup_compatibility(value.model, opts, field)):
raise ValueError(
'Cannot use QuerySet for "%s": Use a QuerySet for "%s".' %
(value.model._meta.object_name, opts.object_name)
)
elif hasattr(value, '_meta'):
self.check_query_object_type(value, opts, field)
elif hasattr(value, '__iter__'):
for v in value:
self.check_query_object_type(v, opts, field)
def check_filterable(self, expression):
"""Raise an error if expression cannot be used in a WHERE clause."""
if not getattr(expression, 'filterable', True):
raise NotSupportedError(
expression.__class__.__name__ + ' is disallowed in the filter '
'clause.'
)
if hasattr(expression, 'get_source_expressions'):
for expr in expression.get_source_expressions():
self.check_filterable(expr)
def build_lookup(self, lookups, lhs, rhs):
"""
Try to extract transforms and lookup from given lhs.
The lhs value is something that works like SQLExpression.
The rhs value is what the lookup is going to compare against.
The lookups is a list of names to extract using get_lookup()
and get_transform().
"""
# __exact is the default lookup if one isn't given.
*transforms, lookup_name = lookups or ['exact']
for name in transforms:
lhs = self.try_transform(lhs, name)
# First try get_lookup() so that the lookup takes precedence if the lhs
# supports both transform and lookup for the name.
lookup_class = lhs.get_lookup(lookup_name)
if not lookup_class:
if lhs.field.is_relation:
raise FieldError('Related Field got invalid lookup: {}'.format(lookup_name))
# A lookup wasn't found. Try to interpret the name as a transform
# and do an Exact lookup against it.
lhs = self.try_transform(lhs, lookup_name)
lookup_name = 'exact'
lookup_class = lhs.get_lookup(lookup_name)
if not lookup_class:
return
lookup = lookup_class(lhs, rhs)
# Interpret '__exact=None' as the sql 'is NULL'; otherwise, reject all
# uses of None as a query value unless the lookup supports it.
if lookup.rhs is None and not lookup.can_use_none_as_rhs:
if lookup_name not in ('exact', 'iexact'):
raise ValueError("Cannot use None as a query value")
return lhs.get_lookup('isnull')(lhs, True)
# For Oracle '' is equivalent to null. The check must be done at this
# stage because join promotion can't be done in the compiler. Using
# DEFAULT_DB_ALIAS isn't nice but it's the best that can be done here.
# A similar thing is done in is_nullable(), too.
if (connections[DEFAULT_DB_ALIAS].features.interprets_empty_strings_as_nulls and
lookup_name == 'exact' and lookup.rhs == ''):
return lhs.get_lookup('isnull')(lhs, True)
return lookup
def try_transform(self, lhs, name):
"""
Helper method for build_lookup(). Try to fetch and initialize
a transform for name parameter from lhs.
"""
transform_class = lhs.get_transform(name)
if transform_class:
return transform_class(lhs)
else:
output_field = lhs.output_field.__class__
suggested_lookups = difflib.get_close_matches(name, output_field.get_lookups())
if suggested_lookups:
suggestion = ', perhaps you meant %s?' % ' or '.join(suggested_lookups)
else:
suggestion = '.'
raise FieldError(
"Unsupported lookup '%s' for %s or join on the field not "
"permitted%s" % (name, output_field.__name__, suggestion)
)
def build_filter(self, filter_expr, branch_negated=False, current_negated=False,
can_reuse=None, allow_joins=True, split_subq=True,
reuse_with_filtered_relation=False, check_filterable=True):
"""
Build a WhereNode for a single filter clause but don't add it
to this Query. Query.add_q() will then add this filter to the where
Node.
The 'branch_negated' tells us if the current branch contains any
negations. This will be used to determine if subqueries are needed.
The 'current_negated' is used to determine if the current filter is
negated or not and this will be used to determine if IS NULL filtering
is needed.
The difference between current_negated and branch_negated is that
branch_negated is set on first negation, but current_negated is
flipped for each negation.
Note that add_filter will not do any negating itself, that is done
upper in the code by add_q().
The 'can_reuse' is a set of reusable joins for multijoins.
If 'reuse_with_filtered_relation' is True, then only joins in can_reuse
will be reused.
The method will create a filter clause that can be added to the current
query. However, if the filter isn't added to the query then the caller
is responsible for unreffing the joins used.
"""
if isinstance(filter_expr, dict):
raise FieldError("Cannot parse keyword query as dict")
if isinstance(filter_expr, Q):
return self._add_q(
filter_expr,
branch_negated=branch_negated,
current_negated=current_negated,
used_aliases=can_reuse,
allow_joins=allow_joins,
split_subq=split_subq,
check_filterable=check_filterable,
)
if hasattr(filter_expr, 'resolve_expression'):
if not getattr(filter_expr, 'conditional', False):
raise TypeError('Cannot filter against a non-conditional expression.')
condition = self.build_lookup(
['exact'], filter_expr.resolve_expression(self, allow_joins=allow_joins), True
)
clause = self.where_class()
clause.add(condition, AND)
return clause, []
arg, value = filter_expr
if not arg:
raise FieldError("Cannot parse keyword query %r" % arg)
lookups, parts, reffed_expression = self.solve_lookup_type(arg)
if check_filterable:
self.check_filterable(reffed_expression)
if not allow_joins and len(parts) > 1:
raise FieldError("Joined field references are not permitted in this query")
pre_joins = self.alias_refcount.copy()
value = self.resolve_lookup_value(value, can_reuse, allow_joins)
used_joins = {k for k, v in self.alias_refcount.items() if v > pre_joins.get(k, 0)}
if check_filterable:
self.check_filterable(value)
clause = self.where_class()
if reffed_expression:
condition = self.build_lookup(lookups, reffed_expression, value)
clause.add(condition, AND)
return clause, []
opts = self.get_meta()
alias = self.get_initial_alias()
allow_many = not branch_negated or not split_subq
try:
join_info = self.setup_joins(
parts, opts, alias, can_reuse=can_reuse, allow_many=allow_many,
reuse_with_filtered_relation=reuse_with_filtered_relation,
)
# Prevent iterator from being consumed by check_related_objects()
if isinstance(value, Iterator):
value = list(value)
self.check_related_objects(join_info.final_field, value, join_info.opts)
# split_exclude() needs to know which joins were generated for the
# lookup parts
self._lookup_joins = join_info.joins
except MultiJoin as e:
return self.split_exclude(filter_expr, can_reuse, e.names_with_path)
# Update used_joins before trimming since they are reused to determine
# which joins could be later promoted to INNER.
used_joins.update(join_info.joins)
targets, alias, join_list = self.trim_joins(join_info.targets, join_info.joins, join_info.path)
if can_reuse is not None:
can_reuse.update(join_list)
if join_info.final_field.is_relation:
# No support for transforms for relational fields
num_lookups = len(lookups)
if num_lookups > 1:
raise FieldError('Related Field got invalid lookup: {}'.format(lookups[0]))
if len(targets) == 1:
col = self._get_col(targets[0], join_info.final_field, alias)
else:
col = MultiColSource(alias, targets, join_info.targets, join_info.final_field)
else:
col = self._get_col(targets[0], join_info.final_field, alias)
condition = self.build_lookup(lookups, col, value)
lookup_type = condition.lookup_name
clause.add(condition, AND)
require_outer = lookup_type == 'isnull' and condition.rhs is True and not current_negated
if current_negated and (lookup_type != 'isnull' or condition.rhs is False) and condition.rhs is not None:
require_outer = True
if (lookup_type != 'isnull' and (
self.is_nullable(targets[0]) or
self.alias_map[join_list[-1]].join_type == LOUTER)):
# The condition added here will be SQL like this:
# NOT (col IS NOT NULL), where the first NOT is added in
# upper layers of code. The reason for addition is that if col
# is null, then col != someval will result in SQL "unknown"
# which isn't the same as in Python. The Python None handling
# is wanted, and it can be gotten by
# (col IS NULL OR col != someval)
# <=>
# NOT (col IS NOT NULL AND col = someval).
lookup_class = targets[0].get_lookup('isnull')
col = self._get_col(targets[0], join_info.targets[0], alias)
clause.add(lookup_class(col, False), AND)
return clause, used_joins if not require_outer else ()
def add_filter(self, filter_clause):
self.add_q(Q(**{filter_clause[0]: filter_clause[1]}))
def add_q(self, q_object):
"""
A preprocessor for the internal _add_q(). Responsible for doing final
join promotion.
"""
# For join promotion this case is doing an AND for the added q_object
# and existing conditions. So, any existing inner join forces the join
# type to remain inner. Existing outer joins can however be demoted.
# (Consider case where rel_a is LOUTER and rel_a__col=1 is added - if
# rel_a doesn't produce any rows, then the whole condition must fail.
# So, demotion is OK.
existing_inner = {a for a in self.alias_map if self.alias_map[a].join_type == INNER}
clause, _ = self._add_q(q_object, self.used_aliases)
if clause:
self.where.add(clause, AND)
self.demote_joins(existing_inner)
def build_where(self, filter_expr):
return self.build_filter(filter_expr, allow_joins=False)[0]
def _add_q(self, q_object, used_aliases, branch_negated=False,
current_negated=False, allow_joins=True, split_subq=True,
check_filterable=True):
"""Add a Q-object to the current filter."""
connector = q_object.connector
current_negated = current_negated ^ q_object.negated
branch_negated = branch_negated or q_object.negated
target_clause = self.where_class(connector=connector,
negated=q_object.negated)
joinpromoter = JoinPromoter(q_object.connector, len(q_object.children), current_negated)
for child in q_object.children:
child_clause, needed_inner = self.build_filter(
child, can_reuse=used_aliases, branch_negated=branch_negated,
current_negated=current_negated, allow_joins=allow_joins,
split_subq=split_subq, check_filterable=check_filterable,
)
joinpromoter.add_votes(needed_inner)
if child_clause:
target_clause.add(child_clause, connector)
needed_inner = joinpromoter.update_join_types(self)
return target_clause, needed_inner
def build_filtered_relation_q(self, q_object, reuse, branch_negated=False, current_negated=False):
"""Add a FilteredRelation object to the current filter."""
connector = q_object.connector
current_negated ^= q_object.negated
branch_negated = branch_negated or q_object.negated
target_clause = self.where_class(connector=connector, negated=q_object.negated)
for child in q_object.children:
if isinstance(child, Node):
child_clause = self.build_filtered_relation_q(
child, reuse=reuse, branch_negated=branch_negated,
current_negated=current_negated,
)
else:
child_clause, _ = self.build_filter(
child, can_reuse=reuse, branch_negated=branch_negated,
current_negated=current_negated,
allow_joins=True, split_subq=False,
reuse_with_filtered_relation=True,
)
target_clause.add(child_clause, connector)
return target_clause
def add_filtered_relation(self, filtered_relation, alias):
filtered_relation.alias = alias
lookups = dict(get_children_from_q(filtered_relation.condition))
for lookup in chain((filtered_relation.relation_name,), lookups):
lookup_parts, field_parts, _ = self.solve_lookup_type(lookup)
shift = 2 if not lookup_parts else 1
if len(field_parts) > (shift + len(lookup_parts)):
raise ValueError(
"FilteredRelation's condition doesn't support nested "
"relations (got %r)." % lookup
)
self._filtered_relations[filtered_relation.alias] = filtered_relation
def names_to_path(self, names, opts, allow_many=True, fail_on_missing=False):
"""
Walk the list of names and turns them into PathInfo tuples. A single
name in 'names' can generate multiple PathInfos (m2m, for example).
'names' is the path of names to travel, 'opts' is the model Options we
start the name resolving from, 'allow_many' is as for setup_joins().
If fail_on_missing is set to True, then a name that can't be resolved
will generate a FieldError.
Return a list of PathInfo tuples. In addition return the final field
(the last used join field) and target (which is a field guaranteed to
contain the same value as the final field). Finally, return those names
that weren't found (which are likely transforms and the final lookup).
"""
path, names_with_path = [], []
for pos, name in enumerate(names):
cur_names_with_path = (name, [])
if name == 'pk':
name = opts.pk.name
field = None
filtered_relation = None
try:
field = opts.get_field(name)
except FieldDoesNotExist:
if name in self.annotation_select:
field = self.annotation_select[name].output_field
elif name in self._filtered_relations and pos == 0:
filtered_relation = self._filtered_relations[name]
field = opts.get_field(filtered_relation.relation_name)
if field is not None:
# Fields that contain one-to-many relations with a generic
# model (like a GenericForeignKey) cannot generate reverse
# relations and therefore cannot be used for reverse querying.
if field.is_relation and not field.related_model:
raise FieldError(
"Field %r does not generate an automatic reverse "
"relation and therefore cannot be used for reverse "
"querying. If it is a GenericForeignKey, consider "
"adding a GenericRelation." % name
)
try:
model = field.model._meta.concrete_model
except AttributeError:
# QuerySet.annotate() may introduce fields that aren't
# attached to a model.
model = None
else:
# We didn't find the current field, so move position back
# one step.
pos -= 1
if pos == -1 or fail_on_missing:
available = sorted([
*get_field_names_from_opts(opts),
*self.annotation_select,
*self._filtered_relations,
])
raise FieldError("Cannot resolve keyword '%s' into field. "
"Choices are: %s" % (name, ", ".join(available)))
break
# Check if we need any joins for concrete inheritance cases (the
# field lives in parent, but we are currently in one of its
# children)
if model is not opts.model:
path_to_parent = opts.get_path_to_parent(model)
if path_to_parent:
path.extend(path_to_parent)
cur_names_with_path[1].extend(path_to_parent)
opts = path_to_parent[-1].to_opts
if hasattr(field, 'get_path_info'):
pathinfos = field.get_path_info(filtered_relation)
if not allow_many:
for inner_pos, p in enumerate(pathinfos):
if p.m2m:
cur_names_with_path[1].extend(pathinfos[0:inner_pos + 1])
names_with_path.append(cur_names_with_path)
raise MultiJoin(pos + 1, names_with_path)
last = pathinfos[-1]
path.extend(pathinfos)
final_field = last.join_field
opts = last.to_opts
targets = last.target_fields
cur_names_with_path[1].extend(pathinfos)
names_with_path.append(cur_names_with_path)
else:
# Local non-relational field.
final_field = field
targets = (field,)
if fail_on_missing and pos + 1 != len(names):
raise FieldError(
"Cannot resolve keyword %r into field. Join on '%s'"
" not permitted." % (names[pos + 1], name))
break
return path, final_field, targets, names[pos + 1:]
def setup_joins(self, names, opts, alias, can_reuse=None, allow_many=True,
reuse_with_filtered_relation=False):
"""
Compute the necessary table joins for the passage through the fields
given in 'names'. 'opts' is the Options class for the current model
(which gives the table we are starting from), 'alias' is the alias for
the table to start the joining from.
The 'can_reuse' defines the reverse foreign key joins we can reuse. It
can be None in which case all joins are reusable or a set of aliases
that can be reused. Note that non-reverse foreign keys are always
reusable when using setup_joins().
The 'reuse_with_filtered_relation' can be used to force 'can_reuse'
parameter and force the relation on the given connections.
If 'allow_many' is False, then any reverse foreign key seen will
generate a MultiJoin exception.
Return the final field involved in the joins, the target field (used
for any 'where' constraint), the final 'opts' value, the joins, the
field path traveled to generate the joins, and a transform function
that takes a field and alias and is equivalent to `field.get_col(alias)`
in the simple case but wraps field transforms if they were included in
names.
The target field is the field containing the concrete value. Final
field can be something different, for example foreign key pointing to
that value. Final field is needed for example in some value
conversions (convert 'obj' in fk__id=obj to pk val using the foreign
key field for example).
"""
joins = [alias]
# The transform can't be applied yet, as joins must be trimmed later.
# To avoid making every caller of this method look up transforms
# directly, compute transforms here and create a partial that converts
# fields to the appropriate wrapped version.
def final_transformer(field, alias):
return field.get_col(alias)
# Try resolving all the names as fields first. If there's an error,
# treat trailing names as lookups until a field can be resolved.
last_field_exception = None
for pivot in range(len(names), 0, -1):
try:
path, final_field, targets, rest = self.names_to_path(
names[:pivot], opts, allow_many, fail_on_missing=True,
)
except FieldError as exc:
if pivot == 1:
# The first item cannot be a lookup, so it's safe
# to raise the field error here.
raise
else:
last_field_exception = exc
else:
# The transforms are the remaining items that couldn't be
# resolved into fields.
transforms = names[pivot:]
break
for name in transforms:
def transform(field, alias, *, name, previous):
try:
wrapped = previous(field, alias)
return self.try_transform(wrapped, name)
except FieldError:
# FieldError is raised if the transform doesn't exist.
if isinstance(final_field, Field) and last_field_exception:
raise last_field_exception
else:
raise
final_transformer = functools.partial(transform, name=name, previous=final_transformer)
# Then, add the path to the query's joins. Note that we can't trim
# joins at this stage - we will need the information about join type
# of the trimmed joins.
for join in path:
if join.filtered_relation:
filtered_relation = join.filtered_relation.clone()
table_alias = filtered_relation.alias
else:
filtered_relation = None
table_alias = None
opts = join.to_opts
if join.direct:
nullable = self.is_nullable(join.join_field)
else:
nullable = True
connection = Join(
opts.db_table, alias, table_alias, INNER, join.join_field,
nullable, filtered_relation=filtered_relation,
)
reuse = can_reuse if join.m2m or reuse_with_filtered_relation else None
alias = self.join(
connection, reuse=reuse,
reuse_with_filtered_relation=reuse_with_filtered_relation,
)
joins.append(alias)
if filtered_relation:
filtered_relation.path = joins[:]
return JoinInfo(final_field, targets, opts, joins, path, final_transformer)
def trim_joins(self, targets, joins, path):
"""
The 'target' parameter is the final field being joined to, 'joins'
is the full list of join aliases. The 'path' contain the PathInfos
used to create the joins.
Return the final target field and table alias and the new active
joins.
Always trim any direct join if the target column is already in the
previous table. Can't trim reverse joins as it's unknown if there's
anything on the other side of the join.
"""
joins = joins[:]
for pos, info in enumerate(reversed(path)):
if len(joins) == 1 or not info.direct:
break
if info.filtered_relation:
break
join_targets = {t.column for t in info.join_field.foreign_related_fields}
cur_targets = {t.column for t in targets}
if not cur_targets.issubset(join_targets):
break
targets_dict = {r[1].column: r[0] for r in info.join_field.related_fields if r[1].column in cur_targets}
targets = tuple(targets_dict[t.column] for t in targets)
self.unref_alias(joins.pop())
return targets, joins[-1], joins
@classmethod
def _gen_cols(cls, exprs):
for expr in exprs:
if isinstance(expr, Col):
yield expr
else:
yield from cls._gen_cols(expr.get_source_expressions())
@classmethod
def _gen_col_aliases(cls, exprs):
yield from (expr.alias for expr in cls._gen_cols(exprs))
def resolve_ref(self, name, allow_joins=True, reuse=None, summarize=False):
if not allow_joins and LOOKUP_SEP in name:
raise FieldError("Joined field references are not permitted in this query")
annotation = self.annotations.get(name)
if annotation is not None:
if not allow_joins:
for alias in self._gen_col_aliases([annotation]):
if isinstance(self.alias_map[alias], Join):
raise FieldError(
'Joined field references are not permitted in '
'this query'
)
if summarize:
# Summarize currently means we are doing an aggregate() query
# which is executed as a wrapped subquery if any of the
# aggregate() elements reference an existing annotation. In
# that case we need to return a Ref to the subquery's annotation.
return Ref(name, self.annotation_select[name])
else:
return annotation
else:
field_list = name.split(LOOKUP_SEP)
join_info = self.setup_joins(field_list, self.get_meta(), self.get_initial_alias(), can_reuse=reuse)
targets, final_alias, join_list = self.trim_joins(join_info.targets, join_info.joins, join_info.path)
if not allow_joins and len(join_list) > 1:
raise FieldError('Joined field references are not permitted in this query')
if len(targets) > 1:
raise FieldError("Referencing multicolumn fields with F() objects "
"isn't supported")
# Verify that the last lookup in name is a field or a transform:
# transform_function() raises FieldError if not.
join_info.transform_function(targets[0], final_alias)
if reuse is not None:
reuse.update(join_list)
return self._get_col(targets[0], join_info.targets[0], join_list[-1])
def split_exclude(self, filter_expr, can_reuse, names_with_path):
"""
When doing an exclude against any kind of N-to-many relation, we need
to use a subquery. This method constructs the nested query, given the
original exclude filter (filter_expr) and the portion up to the first
N-to-many relation field.
For example, if the origin filter is ~Q(child__name='foo'), filter_expr
is ('child__name', 'foo') and can_reuse is a set of joins usable for
filters in the original query.
We will turn this into equivalent of:
WHERE NOT (pk IN (SELECT parent_id FROM thetable
WHERE name = 'foo' AND parent_id IS NOT NULL))
It might be worth it to consider using WHERE NOT EXISTS as that has
saner null handling, and is easier for the backend's optimizer to
handle.
"""
filter_lhs, filter_rhs = filter_expr
if isinstance(filter_rhs, OuterRef):
filter_expr = (filter_lhs, OuterRef(filter_rhs))
elif isinstance(filter_rhs, F):
filter_expr = (filter_lhs, OuterRef(filter_rhs.name))
# Generate the inner query.
query = Query(self.model)
query._filtered_relations = self._filtered_relations
query.add_filter(filter_expr)
query.clear_ordering(True)
# Try to have as simple as possible subquery -> trim leading joins from
# the subquery.
trimmed_prefix, contains_louter = query.trim_start(names_with_path)
# Add extra check to make sure the selected field will not be null
# since we are adding an IN <subquery> clause. This prevents the
# database from tripping over IN (...,NULL,...) selects and returning
# nothing
col = query.select[0]
select_field = col.target
alias = col.alias
if self.is_nullable(select_field):
lookup_class = select_field.get_lookup('isnull')
lookup = lookup_class(select_field.get_col(alias), False)
query.where.add(lookup, AND)
if alias in can_reuse:
pk = select_field.model._meta.pk
# Need to add a restriction so that outer query's filters are in effect for
# the subquery, too.
query.bump_prefix(self)
lookup_class = select_field.get_lookup('exact')
# Note that the query.select[0].alias is different from alias
# due to bump_prefix above.
lookup = lookup_class(pk.get_col(query.select[0].alias),
pk.get_col(alias))
query.where.add(lookup, AND)
query.external_aliases[alias] = True
condition, needed_inner = self.build_filter(
('%s__in' % trimmed_prefix, query),
current_negated=True, branch_negated=True, can_reuse=can_reuse)
if contains_louter:
or_null_condition, _ = self.build_filter(
('%s__isnull' % trimmed_prefix, True),
current_negated=True, branch_negated=True, can_reuse=can_reuse)
condition.add(or_null_condition, OR)
# Note that the end result will be:
# (outercol NOT IN innerq AND outercol IS NOT NULL) OR outercol IS NULL.
# This might look crazy but due to how IN works, this seems to be
# correct. If the IS NOT NULL check is removed then outercol NOT
# IN will return UNKNOWN. If the IS NULL check is removed, then if
# outercol IS NULL we will not match the row.
return condition, needed_inner
def set_empty(self):
self.where.add(NothingNode(), AND)
def is_empty(self):
return any(isinstance(c, NothingNode) for c in self.where.children)
def set_limits(self, low=None, high=None):
"""
Adjust the limits on the rows retrieved. Use low/high to set these,
as it makes it more Pythonic to read and write. When the SQL query is
created, convert them to the appropriate offset and limit values.
Apply any limits passed in here to the existing constraints. Add low
to the current low value and clamp both to any existing high value.
"""
if high is not None:
if self.high_mark is not None:
self.high_mark = min(self.high_mark, self.low_mark + high)
else:
self.high_mark = self.low_mark + high
if low is not None:
if self.high_mark is not None:
self.low_mark = min(self.high_mark, self.low_mark + low)
else:
self.low_mark = self.low_mark + low
if self.low_mark == self.high_mark:
self.set_empty()
def clear_limits(self):
"""Clear any existing limits."""
self.low_mark, self.high_mark = 0, None
@property
def is_sliced(self):
return self.low_mark != 0 or self.high_mark is not None
def has_limit_one(self):
return self.high_mark is not None and (self.high_mark - self.low_mark) == 1
def can_filter(self):
"""
Return True if adding filters to this instance is still possible.
Typically, this means no limits or offsets have been put on the results.
"""
return not self.is_sliced
def clear_select_clause(self):
"""Remove all fields from SELECT clause."""
self.select = ()
self.default_cols = False
self.select_related = False
self.set_extra_mask(())
self.set_annotation_mask(())
def clear_select_fields(self):
"""
Clear the list of fields to select (but not extra_select columns).
Some queryset types completely replace any existing list of select
columns.
"""
self.select = ()
self.values_select = ()
def add_select_col(self, col):
self.select += col,
self.values_select += col.output_field.name,
def set_select(self, cols):
self.default_cols = False
self.select = tuple(cols)
def add_distinct_fields(self, *field_names):
"""
Add and resolve the given fields to the query's "distinct on" clause.
"""
self.distinct_fields = field_names
self.distinct = True
def add_fields(self, field_names, allow_m2m=True):
"""
Add the given (model) fields to the select set. Add the field names in
the order specified.
"""
alias = self.get_initial_alias()
opts = self.get_meta()
try:
cols = []
for name in field_names:
# Join promotion note - we must not remove any rows here, so
# if there is no existing joins, use outer join.
join_info = self.setup_joins(name.split(LOOKUP_SEP), opts, alias, allow_many=allow_m2m)
targets, final_alias, joins = self.trim_joins(
join_info.targets,
join_info.joins,
join_info.path,
)
for target in targets:
cols.append(join_info.transform_function(target, final_alias))
if cols:
self.set_select(cols)
except MultiJoin:
raise FieldError("Invalid field name: '%s'" % name)
except FieldError:
if LOOKUP_SEP in name:
# For lookups spanning over relationships, show the error
# from the model on which the lookup failed.
raise
else:
names = sorted([
*get_field_names_from_opts(opts), *self.extra,
*self.annotation_select, *self._filtered_relations
])
raise FieldError("Cannot resolve keyword %r into field. "
"Choices are: %s" % (name, ", ".join(names)))
def add_ordering(self, *ordering):
"""
Add items from the 'ordering' sequence to the query's "order by"
clause. These items are either field names (not column names) --
possibly with a direction prefix ('-' or '?') -- or OrderBy
expressions.
If 'ordering' is empty, clear all ordering from the query.
"""
errors = []
for item in ordering:
if isinstance(item, str):
if '.' in item:
warnings.warn(
'Passing column raw column aliases to order_by() is '
'deprecated. Wrap %r in a RawSQL expression before '
'passing it to order_by().' % item,
category=RemovedInDjango40Warning,
stacklevel=3,
)
continue
if item == '?':
continue
if item.startswith('-'):
item = item[1:]
if item in self.annotations:
continue
if self.extra and item in self.extra:
continue
# names_to_path() validates the lookup. A descriptive
# FieldError will be raise if it's not.
self.names_to_path(item.split(LOOKUP_SEP), self.model._meta)
elif not hasattr(item, 'resolve_expression'):
errors.append(item)
if getattr(item, 'contains_aggregate', False):
raise FieldError(
'Using an aggregate in order_by() without also including '
'it in annotate() is not allowed: %s' % item
)
if errors:
raise FieldError('Invalid order_by arguments: %s' % errors)
if ordering:
self.order_by += ordering
else:
self.default_ordering = False
def clear_ordering(self, force_empty):
"""
Remove any ordering settings. If 'force_empty' is True, there will be
no ordering in the resulting query (not even the model's default).
"""
self.order_by = ()
self.extra_order_by = ()
if force_empty:
self.default_ordering = False
def set_group_by(self, allow_aliases=True):
"""
Expand the GROUP BY clause required by the query.
This will usually be the set of all non-aggregate fields in the
return data. If the database backend supports grouping by the
primary key, and the query would be equivalent, the optimization
will be made automatically.
"""
# Column names from JOINs to check collisions with aliases.
if allow_aliases:
column_names = set()
seen_models = set()
for join in list(self.alias_map.values())[1:]: # Skip base table.
model = join.join_field.related_model
if model not in seen_models:
column_names.update({
field.column
for field in model._meta.local_concrete_fields
})
seen_models.add(model)
group_by = list(self.select)
if self.annotation_select:
for alias, annotation in self.annotation_select.items():
signature = inspect.signature(annotation.get_group_by_cols)
if 'alias' not in signature.parameters:
annotation_class = annotation.__class__
msg = (
'`alias=None` must be added to the signature of '
'%s.%s.get_group_by_cols().'
) % (annotation_class.__module__, annotation_class.__qualname__)
warnings.warn(msg, category=RemovedInDjango40Warning)
group_by_cols = annotation.get_group_by_cols()
else:
if not allow_aliases or alias in column_names:
alias = None
group_by_cols = annotation.get_group_by_cols(alias=alias)
group_by.extend(group_by_cols)
self.group_by = tuple(group_by)
def add_select_related(self, fields):
"""
Set up the select_related data structure so that we only select
certain related models (as opposed to all models, when
self.select_related=True).
"""
if isinstance(self.select_related, bool):
field_dict = {}
else:
field_dict = self.select_related
for field in fields:
d = field_dict
for part in field.split(LOOKUP_SEP):
d = d.setdefault(part, {})
self.select_related = field_dict
def add_extra(self, select, select_params, where, params, tables, order_by):
"""
Add data to the various extra_* attributes for user-created additions
to the query.
"""
if select:
# We need to pair any placeholder markers in the 'select'
# dictionary with their parameters in 'select_params' so that
# subsequent updates to the select dictionary also adjust the
# parameters appropriately.
select_pairs = {}
if select_params:
param_iter = iter(select_params)
else:
param_iter = iter([])
for name, entry in select.items():
entry = str(entry)
entry_params = []
pos = entry.find("%s")
while pos != -1:
if pos == 0 or entry[pos - 1] != '%':
entry_params.append(next(param_iter))
pos = entry.find("%s", pos + 2)
select_pairs[name] = (entry, entry_params)
self.extra.update(select_pairs)
if where or params:
self.where.add(ExtraWhere(where, params), AND)
if tables:
self.extra_tables += tuple(tables)
if order_by:
self.extra_order_by = order_by
def clear_deferred_loading(self):
"""Remove any fields from the deferred loading set."""
self.deferred_loading = (frozenset(), True)
def add_deferred_loading(self, field_names):
"""
Add the given list of model field names to the set of fields to
exclude from loading from the database when automatic column selection
is done. Add the new field names to any existing field names that
are deferred (or removed from any existing field names that are marked
as the only ones for immediate loading).
"""
# Fields on related models are stored in the literal double-underscore
# format, so that we can use a set datastructure. We do the foo__bar
# splitting and handling when computing the SQL column names (as part of
# get_columns()).
existing, defer = self.deferred_loading
if defer:
# Add to existing deferred names.
self.deferred_loading = existing.union(field_names), True
else:
# Remove names from the set of any existing "immediate load" names.
self.deferred_loading = existing.difference(field_names), False
def add_immediate_loading(self, field_names):
"""
Add the given list of model field names to the set of fields to
retrieve when the SQL is executed ("immediate loading" fields). The
field names replace any existing immediate loading field names. If
there are field names already specified for deferred loading, remove
those names from the new field_names before storing the new names
for immediate loading. (That is, immediate loading overrides any
existing immediate values, but respects existing deferrals.)
"""
existing, defer = self.deferred_loading
field_names = set(field_names)
if 'pk' in field_names:
field_names.remove('pk')
field_names.add(self.get_meta().pk.name)
if defer:
# Remove any existing deferred names from the current set before
# setting the new names.
self.deferred_loading = field_names.difference(existing), False
else:
# Replace any existing "immediate load" field names.
self.deferred_loading = frozenset(field_names), False
def get_loaded_field_names(self):
"""
If any fields are marked to be deferred, return a dictionary mapping
models to a set of names in those fields that will be loaded. If a
model is not in the returned dictionary, none of its fields are
deferred.
If no fields are marked for deferral, return an empty dictionary.
"""
# We cache this because we call this function multiple times
# (compiler.fill_related_selections, query.iterator)
try:
return self._loaded_field_names_cache
except AttributeError:
collection = {}
self.deferred_to_data(collection, self.get_loaded_field_names_cb)
self._loaded_field_names_cache = collection
return collection
def get_loaded_field_names_cb(self, target, model, fields):
"""Callback used by get_deferred_field_names()."""
target[model] = {f.attname for f in fields}
def set_annotation_mask(self, names):
"""Set the mask of annotations that will be returned by the SELECT."""
if names is None:
self.annotation_select_mask = None
else:
self.annotation_select_mask = set(names)
self._annotation_select_cache = None
def append_annotation_mask(self, names):
if self.annotation_select_mask is not None:
self.set_annotation_mask(self.annotation_select_mask.union(names))
def set_extra_mask(self, names):
"""
Set the mask of extra select items that will be returned by SELECT.
Don't remove them from the Query since they might be used later.
"""
if names is None:
self.extra_select_mask = None
else:
self.extra_select_mask = set(names)
self._extra_select_cache = None
def set_values(self, fields):
self.select_related = False
self.clear_deferred_loading()
self.clear_select_fields()
if fields:
field_names = []
extra_names = []
annotation_names = []
if not self.extra and not self.annotations:
# Shortcut - if there are no extra or annotations, then
# the values() clause must be just field names.
field_names = list(fields)
else:
self.default_cols = False
for f in fields:
if f in self.extra_select:
extra_names.append(f)
elif f in self.annotation_select:
annotation_names.append(f)
else:
field_names.append(f)
self.set_extra_mask(extra_names)
self.set_annotation_mask(annotation_names)
else:
field_names = [f.attname for f in self.model._meta.concrete_fields]
# Selected annotations must be known before setting the GROUP BY
# clause.
if self.group_by is True:
self.add_fields((f.attname for f in self.model._meta.concrete_fields), False)
# Disable GROUP BY aliases to avoid orphaning references to the
# SELECT clause which is about to be cleared.
self.set_group_by(allow_aliases=False)
self.clear_select_fields()
self.values_select = tuple(field_names)
self.add_fields(field_names, True)
@property
def annotation_select(self):
"""
Return the dictionary of aggregate columns that are not masked and
should be used in the SELECT clause. Cache this result for performance.
"""
if self._annotation_select_cache is not None:
return self._annotation_select_cache
elif not self.annotations:
return {}
elif self.annotation_select_mask is not None:
self._annotation_select_cache = {
k: v for k, v in self.annotations.items()
if k in self.annotation_select_mask
}
return self._annotation_select_cache
else:
return self.annotations
@property
def extra_select(self):
if self._extra_select_cache is not None:
return self._extra_select_cache
if not self.extra:
return {}
elif self.extra_select_mask is not None:
self._extra_select_cache = {
k: v for k, v in self.extra.items()
if k in self.extra_select_mask
}
return self._extra_select_cache
else:
return self.extra
def trim_start(self, names_with_path):
"""
Trim joins from the start of the join path. The candidates for trim
are the PathInfos in names_with_path structure that are m2m joins.
Also set the select column so the start matches the join.
This method is meant to be used for generating the subquery joins &
cols in split_exclude().
Return a lookup usable for doing outerq.filter(lookup=self) and a
boolean indicating if the joins in the prefix contain a LEFT OUTER join.
_"""
all_paths = []
for _, paths in names_with_path:
all_paths.extend(paths)
contains_louter = False
# Trim and operate only on tables that were generated for
# the lookup part of the query. That is, avoid trimming
# joins generated for F() expressions.
lookup_tables = [
t for t in self.alias_map
if t in self._lookup_joins or t == self.base_table
]
for trimmed_paths, path in enumerate(all_paths):
if path.m2m:
break
if self.alias_map[lookup_tables[trimmed_paths + 1]].join_type == LOUTER:
contains_louter = True
alias = lookup_tables[trimmed_paths]
self.unref_alias(alias)
# The path.join_field is a Rel, lets get the other side's field
join_field = path.join_field.field
# Build the filter prefix.
paths_in_prefix = trimmed_paths
trimmed_prefix = []
for name, path in names_with_path:
if paths_in_prefix - len(path) < 0:
break
trimmed_prefix.append(name)
paths_in_prefix -= len(path)
trimmed_prefix.append(
join_field.foreign_related_fields[0].name)
trimmed_prefix = LOOKUP_SEP.join(trimmed_prefix)
# Lets still see if we can trim the first join from the inner query
# (that is, self). We can't do this for:
# - LEFT JOINs because we would miss those rows that have nothing on
# the outer side,
# - INNER JOINs from filtered relations because we would miss their
# filters.
first_join = self.alias_map[lookup_tables[trimmed_paths + 1]]
if first_join.join_type != LOUTER and not first_join.filtered_relation:
select_fields = [r[0] for r in join_field.related_fields]
select_alias = lookup_tables[trimmed_paths + 1]
self.unref_alias(lookup_tables[trimmed_paths])
extra_restriction = join_field.get_extra_restriction(
self.where_class, None, lookup_tables[trimmed_paths + 1])
if extra_restriction:
self.where.add(extra_restriction, AND)
else:
# TODO: It might be possible to trim more joins from the start of the
# inner query if it happens to have a longer join chain containing the
# values in select_fields. Lets punt this one for now.
select_fields = [r[1] for r in join_field.related_fields]
select_alias = lookup_tables[trimmed_paths]
# The found starting point is likely a Join instead of a BaseTable reference.
# But the first entry in the query's FROM clause must not be a JOIN.
for table in self.alias_map:
if self.alias_refcount[table] > 0:
self.alias_map[table] = BaseTable(self.alias_map[table].table_name, table)
break
self.set_select([f.get_col(select_alias) for f in select_fields])
return trimmed_prefix, contains_louter
def is_nullable(self, field):
"""
Check if the given field should be treated as nullable.
Some backends treat '' as null and Django treats such fields as
nullable for those backends. In such situations field.null can be
False even if we should treat the field as nullable.
"""
# We need to use DEFAULT_DB_ALIAS here, as QuerySet does not have
# (nor should it have) knowledge of which connection is going to be
# used. The proper fix would be to defer all decisions where
# is_nullable() is needed to the compiler stage, but that is not easy
# to do currently.
return (
connections[DEFAULT_DB_ALIAS].features.interprets_empty_strings_as_nulls and
field.empty_strings_allowed
) or field.null
def get_order_dir(field, default='ASC'):
"""
Return the field name and direction for an order specification. For
example, '-foo' is returned as ('foo', 'DESC').
The 'default' param is used to indicate which way no prefix (or a '+'
prefix) should sort. The '-' prefix always sorts the opposite way.
"""
dirn = ORDER_DIR[default]
if field[0] == '-':
return field[1:], dirn[1]
return field, dirn[0]
def add_to_dict(data, key, value):
"""
Add "value" to the set of values for "key", whether or not "key" already
exists.
"""
if key in data:
data[key].add(value)
else:
data[key] = {value}
def is_reverse_o2o(field):
"""
Check if the given field is reverse-o2o. The field is expected to be some
sort of relation field or related object.
"""
return field.is_relation and field.one_to_one and not field.concrete
class JoinPromoter:
"""
A class to abstract away join promotion problems for complex filter
conditions.
"""
def __init__(self, connector, num_children, negated):
self.connector = connector
self.negated = negated
if self.negated:
if connector == AND:
self.effective_connector = OR
else:
self.effective_connector = AND
else:
self.effective_connector = self.connector
self.num_children = num_children
# Maps of table alias to how many times it is seen as required for
# inner and/or outer joins.
self.votes = Counter()
def add_votes(self, votes):
"""
Add single vote per item to self.votes. Parameter can be any
iterable.
"""
self.votes.update(votes)
def update_join_types(self, query):
"""
Change join types so that the generated query is as efficient as
possible, but still correct. So, change as many joins as possible
to INNER, but don't make OUTER joins INNER if that could remove
results from the query.
"""
to_promote = set()
to_demote = set()
# The effective_connector is used so that NOT (a AND b) is treated
# similarly to (a OR b) for join promotion.
for table, votes in self.votes.items():
# We must use outer joins in OR case when the join isn't contained
# in all of the joins. Otherwise the INNER JOIN itself could remove
# valid results. Consider the case where a model with rel_a and
# rel_b relations is queried with rel_a__col=1 | rel_b__col=2. Now,
# if rel_a join doesn't produce any results is null (for example
# reverse foreign key or null value in direct foreign key), and
# there is a matching row in rel_b with col=2, then an INNER join
# to rel_a would remove a valid match from the query. So, we need
# to promote any existing INNER to LOUTER (it is possible this
# promotion in turn will be demoted later on).
if self.effective_connector == 'OR' and votes < self.num_children:
to_promote.add(table)
# If connector is AND and there is a filter that can match only
# when there is a joinable row, then use INNER. For example, in
# rel_a__col=1 & rel_b__col=2, if either of the rels produce NULL
# as join output, then the col=1 or col=2 can't match (as
# NULL=anything is always false).
# For the OR case, if all children voted for a join to be inner,
# then we can use INNER for the join. For example:
# (rel_a__col__icontains=Alex | rel_a__col__icontains=Russell)
# then if rel_a doesn't produce any rows, the whole condition
# can't match. Hence we can safely use INNER join.
if self.effective_connector == 'AND' or (
self.effective_connector == 'OR' and votes == self.num_children):
to_demote.add(table)
# Finally, what happens in cases where we have:
# (rel_a__col=1|rel_b__col=2) & rel_a__col__gte=0
# Now, we first generate the OR clause, and promote joins for it
# in the first if branch above. Both rel_a and rel_b are promoted
# to LOUTER joins. After that we do the AND case. The OR case
# voted no inner joins but the rel_a__col__gte=0 votes inner join
# for rel_a. We demote it back to INNER join (in AND case a single
# vote is enough). The demotion is OK, if rel_a doesn't produce
# rows, then the rel_a__col__gte=0 clause can't be true, and thus
# the whole clause must be false. So, it is safe to use INNER
# join.
# Note that in this example we could just as well have the __gte
# clause and the OR clause swapped. Or we could replace the __gte
# clause with an OR clause containing rel_a__col=1|rel_a__col=2,
# and again we could safely demote to INNER.
query.promote_joins(to_promote)
query.demote_joins(to_demote)
return to_demote
|
d5fa6a0f7259ae4b3c04284c21c531d3189413934629e217cc11894f7f3971a7 | import collections
import re
from functools import partial
from itertools import chain
from django.core.exceptions import EmptyResultSet, FieldError
from django.db import DatabaseError, NotSupportedError
from django.db.models.constants import LOOKUP_SEP
from django.db.models.expressions import OrderBy, Random, RawSQL, Ref, Value
from django.db.models.functions import Cast
from django.db.models.query_utils import Q, select_related_descend
from django.db.models.sql.constants import (
CURSOR, GET_ITERATOR_CHUNK_SIZE, MULTI, NO_RESULTS, ORDER_DIR, SINGLE,
)
from django.db.models.sql.query import Query, get_order_dir
from django.db.transaction import TransactionManagementError
from django.utils.functional import cached_property
from django.utils.hashable import make_hashable
from django.utils.regex_helper import _lazy_re_compile
class SQLCompiler:
# Multiline ordering SQL clause may appear from RawSQL.
ordering_parts = _lazy_re_compile(
r'^(.*)\s(?:ASC|DESC).*',
re.MULTILINE | re.DOTALL,
)
def __init__(self, query, connection, using):
self.query = query
self.connection = connection
self.using = using
self.quote_cache = {'*': '*'}
# The select, klass_info, and annotations are needed by QuerySet.iterator()
# these are set as a side-effect of executing the query. Note that we calculate
# separately a list of extra select columns needed for grammatical correctness
# of the query, but these columns are not included in self.select.
self.select = None
self.annotation_col_map = None
self.klass_info = None
self._meta_ordering = None
def setup_query(self):
if all(self.query.alias_refcount[a] == 0 for a in self.query.alias_map):
self.query.get_initial_alias()
self.select, self.klass_info, self.annotation_col_map = self.get_select()
self.col_count = len(self.select)
def pre_sql_setup(self):
"""
Do any necessary class setup immediately prior to producing SQL. This
is for things that can't necessarily be done in __init__ because we
might not have all the pieces in place at that time.
"""
self.setup_query()
order_by = self.get_order_by()
self.where, self.having = self.query.where.split_having()
extra_select = self.get_extra_select(order_by, self.select)
self.has_extra_select = bool(extra_select)
group_by = self.get_group_by(self.select + extra_select, order_by)
return extra_select, order_by, group_by
def get_group_by(self, select, order_by):
"""
Return a list of 2-tuples of form (sql, params).
The logic of what exactly the GROUP BY clause contains is hard
to describe in other words than "if it passes the test suite,
then it is correct".
"""
# Some examples:
# SomeModel.objects.annotate(Count('somecol'))
# GROUP BY: all fields of the model
#
# SomeModel.objects.values('name').annotate(Count('somecol'))
# GROUP BY: name
#
# SomeModel.objects.annotate(Count('somecol')).values('name')
# GROUP BY: all cols of the model
#
# SomeModel.objects.values('name', 'pk').annotate(Count('somecol')).values('pk')
# GROUP BY: name, pk
#
# SomeModel.objects.values('name').annotate(Count('somecol')).values('pk')
# GROUP BY: name, pk
#
# In fact, the self.query.group_by is the minimal set to GROUP BY. It
# can't be ever restricted to a smaller set, but additional columns in
# HAVING, ORDER BY, and SELECT clauses are added to it. Unfortunately
# the end result is that it is impossible to force the query to have
# a chosen GROUP BY clause - you can almost do this by using the form:
# .values(*wanted_cols).annotate(AnAggregate())
# but any later annotations, extra selects, values calls that
# refer some column outside of the wanted_cols, order_by, or even
# filter calls can alter the GROUP BY clause.
# The query.group_by is either None (no GROUP BY at all), True
# (group by select fields), or a list of expressions to be added
# to the group by.
if self.query.group_by is None:
return []
expressions = []
if self.query.group_by is not True:
# If the group by is set to a list (by .values() call most likely),
# then we need to add everything in it to the GROUP BY clause.
# Backwards compatibility hack for setting query.group_by. Remove
# when we have public API way of forcing the GROUP BY clause.
# Converts string references to expressions.
for expr in self.query.group_by:
if not hasattr(expr, 'as_sql'):
expressions.append(self.query.resolve_ref(expr))
else:
expressions.append(expr)
# Note that even if the group_by is set, it is only the minimal
# set to group by. So, we need to add cols in select, order_by, and
# having into the select in any case.
ref_sources = {
expr.source for expr in expressions if isinstance(expr, Ref)
}
for expr, _, _ in select:
# Skip members of the select clause that are already included
# by reference.
if expr in ref_sources:
continue
cols = expr.get_group_by_cols()
for col in cols:
expressions.append(col)
for expr, (sql, params, is_ref) in order_by:
# Skip References to the select clause, as all expressions in the
# select clause are already part of the group by.
if not is_ref:
expressions.extend(expr.get_group_by_cols())
having_group_by = self.having.get_group_by_cols() if self.having else ()
for expr in having_group_by:
expressions.append(expr)
result = []
seen = set()
expressions = self.collapse_group_by(expressions, having_group_by)
for expr in expressions:
sql, params = self.compile(expr)
params_hash = make_hashable(params)
if (sql, params_hash) not in seen:
result.append((sql, params))
seen.add((sql, params_hash))
return result
def collapse_group_by(self, expressions, having):
# If the DB can group by primary key, then group by the primary key of
# query's main model. Note that for PostgreSQL the GROUP BY clause must
# include the primary key of every table, but for MySQL it is enough to
# have the main table's primary key.
if self.connection.features.allows_group_by_pk:
# Determine if the main model's primary key is in the query.
pk = None
for expr in expressions:
# Is this a reference to query's base table primary key? If the
# expression isn't a Col-like, then skip the expression.
if (getattr(expr, 'target', None) == self.query.model._meta.pk and
getattr(expr, 'alias', None) == self.query.base_table):
pk = expr
break
# If the main model's primary key is in the query, group by that
# field, HAVING expressions, and expressions associated with tables
# that don't have a primary key included in the grouped columns.
if pk:
pk_aliases = {
expr.alias for expr in expressions
if hasattr(expr, 'target') and expr.target.primary_key
}
expressions = [pk] + [
expr for expr in expressions
if expr in having or (
getattr(expr, 'alias', None) is not None and expr.alias not in pk_aliases
)
]
elif self.connection.features.allows_group_by_selected_pks:
# Filter out all expressions associated with a table's primary key
# present in the grouped columns. This is done by identifying all
# tables that have their primary key included in the grouped
# columns and removing non-primary key columns referring to them.
# Unmanaged models are excluded because they could be representing
# database views on which the optimization might not be allowed.
pks = {
expr for expr in expressions
if (
hasattr(expr, 'target') and
expr.target.primary_key and
self.connection.features.allows_group_by_selected_pks_on_model(expr.target.model)
)
}
aliases = {expr.alias for expr in pks}
expressions = [
expr for expr in expressions if expr in pks or getattr(expr, 'alias', None) not in aliases
]
return expressions
def get_select(self):
"""
Return three values:
- a list of 3-tuples of (expression, (sql, params), alias)
- a klass_info structure,
- a dictionary of annotations
The (sql, params) is what the expression will produce, and alias is the
"AS alias" for the column (possibly None).
The klass_info structure contains the following information:
- The base model of the query.
- Which columns for that model are present in the query (by
position of the select clause).
- related_klass_infos: [f, klass_info] to descent into
The annotations is a dictionary of {'attname': column position} values.
"""
select = []
klass_info = None
annotations = {}
select_idx = 0
for alias, (sql, params) in self.query.extra_select.items():
annotations[alias] = select_idx
select.append((RawSQL(sql, params), alias))
select_idx += 1
assert not (self.query.select and self.query.default_cols)
if self.query.default_cols:
cols = self.get_default_columns()
else:
# self.query.select is a special case. These columns never go to
# any model.
cols = self.query.select
if cols:
select_list = []
for col in cols:
select_list.append(select_idx)
select.append((col, None))
select_idx += 1
klass_info = {
'model': self.query.model,
'select_fields': select_list,
}
for alias, annotation in self.query.annotation_select.items():
annotations[alias] = select_idx
select.append((annotation, alias))
select_idx += 1
if self.query.select_related:
related_klass_infos = self.get_related_selections(select)
klass_info['related_klass_infos'] = related_klass_infos
def get_select_from_parent(klass_info):
for ki in klass_info['related_klass_infos']:
if ki['from_parent']:
ki['select_fields'] = (klass_info['select_fields'] +
ki['select_fields'])
get_select_from_parent(ki)
get_select_from_parent(klass_info)
ret = []
for col, alias in select:
try:
sql, params = self.compile(col)
except EmptyResultSet:
# Select a predicate that's always False.
sql, params = '0', ()
else:
sql, params = col.select_format(self, sql, params)
ret.append((col, (sql, params), alias))
return ret, klass_info, annotations
def get_order_by(self):
"""
Return a list of 2-tuples of form (expr, (sql, params, is_ref)) for the
ORDER BY clause.
The order_by clause can alter the select clause (for example it
can add aliases to clauses that do not yet have one, or it can
add totally new select clauses).
"""
if self.query.extra_order_by:
ordering = self.query.extra_order_by
elif not self.query.default_ordering:
ordering = self.query.order_by
elif self.query.order_by:
ordering = self.query.order_by
elif self.query.get_meta().ordering:
ordering = self.query.get_meta().ordering
self._meta_ordering = ordering
else:
ordering = []
if self.query.standard_ordering:
asc, desc = ORDER_DIR['ASC']
else:
asc, desc = ORDER_DIR['DESC']
order_by = []
for field in ordering:
if hasattr(field, 'resolve_expression'):
if isinstance(field, Value):
# output_field must be resolved for constants.
field = Cast(field, field.output_field)
if not isinstance(field, OrderBy):
field = field.asc()
if not self.query.standard_ordering:
field = field.copy()
field.reverse_ordering()
order_by.append((field, False))
continue
if field == '?': # random
order_by.append((OrderBy(Random()), False))
continue
col, order = get_order_dir(field, asc)
descending = order == 'DESC'
if col in self.query.annotation_select:
# Reference to expression in SELECT clause
order_by.append((
OrderBy(Ref(col, self.query.annotation_select[col]), descending=descending),
True))
continue
if col in self.query.annotations:
# References to an expression which is masked out of the SELECT
# clause.
expr = self.query.annotations[col]
if isinstance(expr, Value):
# output_field must be resolved for constants.
expr = Cast(expr, expr.output_field)
order_by.append((OrderBy(expr, descending=descending), False))
continue
if '.' in field:
# This came in through an extra(order_by=...) addition. Pass it
# on verbatim.
table, col = col.split('.', 1)
order_by.append((
OrderBy(
RawSQL('%s.%s' % (self.quote_name_unless_alias(table), col), []),
descending=descending
), False))
continue
if not self.query.extra or col not in self.query.extra:
# 'col' is of the form 'field' or 'field1__field2' or
# '-field1__field2__field', etc.
order_by.extend(self.find_ordering_name(
field, self.query.get_meta(), default_order=asc))
else:
if col not in self.query.extra_select:
order_by.append((
OrderBy(RawSQL(*self.query.extra[col]), descending=descending),
False))
else:
order_by.append((
OrderBy(Ref(col, RawSQL(*self.query.extra[col])), descending=descending),
True))
result = []
seen = set()
for expr, is_ref in order_by:
resolved = expr.resolve_expression(self.query, allow_joins=True, reuse=None)
if self.query.combinator:
src = resolved.get_source_expressions()[0]
# Relabel order by columns to raw numbers if this is a combined
# query; necessary since the columns can't be referenced by the
# fully qualified name and the simple column names may collide.
for idx, (sel_expr, _, col_alias) in enumerate(self.select):
if is_ref and col_alias == src.refs:
src = src.source
elif col_alias:
continue
if src == sel_expr:
resolved.set_source_expressions([RawSQL('%d' % (idx + 1), ())])
break
else:
if col_alias:
raise DatabaseError('ORDER BY term does not match any column in the result set.')
# Add column used in ORDER BY clause without an alias to
# the selected columns.
self.query.add_select_col(src)
resolved.set_source_expressions([RawSQL('%d' % len(self.query.select), ())])
sql, params = self.compile(resolved)
# Don't add the same column twice, but the order direction is
# not taken into account so we strip it. When this entire method
# is refactored into expressions, then we can check each part as we
# generate it.
without_ordering = self.ordering_parts.search(sql).group(1)
params_hash = make_hashable(params)
if (without_ordering, params_hash) in seen:
continue
seen.add((without_ordering, params_hash))
result.append((resolved, (sql, params, is_ref)))
return result
def get_extra_select(self, order_by, select):
extra_select = []
if self.query.distinct and not self.query.distinct_fields:
select_sql = [t[1] for t in select]
for expr, (sql, params, is_ref) in order_by:
without_ordering = self.ordering_parts.search(sql).group(1)
if not is_ref and (without_ordering, params) not in select_sql:
extra_select.append((expr, (without_ordering, params), None))
return extra_select
def quote_name_unless_alias(self, name):
"""
A wrapper around connection.ops.quote_name that doesn't quote aliases
for table names. This avoids problems with some SQL dialects that treat
quoted strings specially (e.g. PostgreSQL).
"""
if name in self.quote_cache:
return self.quote_cache[name]
if ((name in self.query.alias_map and name not in self.query.table_map) or
name in self.query.extra_select or (
self.query.external_aliases.get(name) and name not in self.query.table_map)):
self.quote_cache[name] = name
return name
r = self.connection.ops.quote_name(name)
self.quote_cache[name] = r
return r
def compile(self, node):
vendor_impl = getattr(node, 'as_' + self.connection.vendor, None)
if vendor_impl:
sql, params = vendor_impl(self, self.connection)
else:
sql, params = node.as_sql(self, self.connection)
return sql, params
def get_combinator_sql(self, combinator, all):
features = self.connection.features
compilers = [
query.get_compiler(self.using, self.connection)
for query in self.query.combined_queries if not query.is_empty()
]
if not features.supports_slicing_ordering_in_compound:
for query, compiler in zip(self.query.combined_queries, compilers):
if query.low_mark or query.high_mark:
raise DatabaseError('LIMIT/OFFSET not allowed in subqueries of compound statements.')
if compiler.get_order_by():
raise DatabaseError('ORDER BY not allowed in subqueries of compound statements.')
parts = ()
for compiler in compilers:
try:
# If the columns list is limited, then all combined queries
# must have the same columns list. Set the selects defined on
# the query on all combined queries, if not already set.
if not compiler.query.values_select and self.query.values_select:
compiler.query = compiler.query.clone()
compiler.query.set_values((
*self.query.extra_select,
*self.query.values_select,
*self.query.annotation_select,
))
part_sql, part_args = compiler.as_sql()
if compiler.query.combinator:
# Wrap in a subquery if wrapping in parentheses isn't
# supported.
if not features.supports_parentheses_in_compound:
part_sql = 'SELECT * FROM ({})'.format(part_sql)
# Add parentheses when combining with compound query if not
# already added for all compound queries.
elif not features.supports_slicing_ordering_in_compound:
part_sql = '({})'.format(part_sql)
parts += ((part_sql, part_args),)
except EmptyResultSet:
# Omit the empty queryset with UNION and with DIFFERENCE if the
# first queryset is nonempty.
if combinator == 'union' or (combinator == 'difference' and parts):
continue
raise
if not parts:
raise EmptyResultSet
combinator_sql = self.connection.ops.set_operators[combinator]
if all and combinator == 'union':
combinator_sql += ' ALL'
braces = '({})' if features.supports_slicing_ordering_in_compound else '{}'
sql_parts, args_parts = zip(*((braces.format(sql), args) for sql, args in parts))
result = [' {} '.format(combinator_sql).join(sql_parts)]
params = []
for part in args_parts:
params.extend(part)
return result, params
def as_sql(self, with_limits=True, with_col_aliases=False):
"""
Create the SQL for this query. Return the SQL string and list of
parameters.
If 'with_limits' is False, any limit/offset information is not included
in the query.
"""
refcounts_before = self.query.alias_refcount.copy()
try:
extra_select, order_by, group_by = self.pre_sql_setup()
for_update_part = None
# Is a LIMIT/OFFSET clause needed?
with_limit_offset = with_limits and (self.query.high_mark is not None or self.query.low_mark)
combinator = self.query.combinator
features = self.connection.features
if combinator:
if not getattr(features, 'supports_select_{}'.format(combinator)):
raise NotSupportedError('{} is not supported on this database backend.'.format(combinator))
result, params = self.get_combinator_sql(combinator, self.query.combinator_all)
else:
distinct_fields, distinct_params = self.get_distinct()
# This must come after 'select', 'ordering', and 'distinct'
# (see docstring of get_from_clause() for details).
from_, f_params = self.get_from_clause()
where, w_params = self.compile(self.where) if self.where is not None else ("", [])
having, h_params = self.compile(self.having) if self.having is not None else ("", [])
result = ['SELECT']
params = []
if self.query.distinct:
distinct_result, distinct_params = self.connection.ops.distinct_sql(
distinct_fields,
distinct_params,
)
result += distinct_result
params += distinct_params
out_cols = []
col_idx = 1
for _, (s_sql, s_params), alias in self.select + extra_select:
if alias:
s_sql = '%s AS %s' % (s_sql, self.connection.ops.quote_name(alias))
elif with_col_aliases:
s_sql = '%s AS %s' % (s_sql, 'Col%d' % col_idx)
col_idx += 1
params.extend(s_params)
out_cols.append(s_sql)
result += [', '.join(out_cols), 'FROM', *from_]
params.extend(f_params)
if self.query.select_for_update and self.connection.features.has_select_for_update:
if self.connection.get_autocommit():
raise TransactionManagementError('select_for_update cannot be used outside of a transaction.')
if with_limit_offset and not self.connection.features.supports_select_for_update_with_limit:
raise NotSupportedError(
'LIMIT/OFFSET is not supported with '
'select_for_update on this database backend.'
)
nowait = self.query.select_for_update_nowait
skip_locked = self.query.select_for_update_skip_locked
of = self.query.select_for_update_of
# If it's a NOWAIT/SKIP LOCKED/OF query but the backend
# doesn't support it, raise NotSupportedError to prevent a
# possible deadlock.
if nowait and not self.connection.features.has_select_for_update_nowait:
raise NotSupportedError('NOWAIT is not supported on this database backend.')
elif skip_locked and not self.connection.features.has_select_for_update_skip_locked:
raise NotSupportedError('SKIP LOCKED is not supported on this database backend.')
elif of and not self.connection.features.has_select_for_update_of:
raise NotSupportedError('FOR UPDATE OF is not supported on this database backend.')
for_update_part = self.connection.ops.for_update_sql(
nowait=nowait,
skip_locked=skip_locked,
of=self.get_select_for_update_of_arguments(),
)
if for_update_part and self.connection.features.for_update_after_from:
result.append(for_update_part)
if where:
result.append('WHERE %s' % where)
params.extend(w_params)
grouping = []
for g_sql, g_params in group_by:
grouping.append(g_sql)
params.extend(g_params)
if grouping:
if distinct_fields:
raise NotImplementedError('annotate() + distinct(fields) is not implemented.')
order_by = order_by or self.connection.ops.force_no_ordering()
result.append('GROUP BY %s' % ', '.join(grouping))
if self._meta_ordering:
order_by = None
if having:
result.append('HAVING %s' % having)
params.extend(h_params)
if self.query.explain_query:
result.insert(0, self.connection.ops.explain_query_prefix(
self.query.explain_format,
**self.query.explain_options
))
if order_by:
ordering = []
for _, (o_sql, o_params, _) in order_by:
ordering.append(o_sql)
params.extend(o_params)
result.append('ORDER BY %s' % ', '.join(ordering))
if with_limit_offset:
result.append(self.connection.ops.limit_offset_sql(self.query.low_mark, self.query.high_mark))
if for_update_part and not self.connection.features.for_update_after_from:
result.append(for_update_part)
if self.query.subquery and extra_select:
# If the query is used as a subquery, the extra selects would
# result in more columns than the left-hand side expression is
# expecting. This can happen when a subquery uses a combination
# of order_by() and distinct(), forcing the ordering expressions
# to be selected as well. Wrap the query in another subquery
# to exclude extraneous selects.
sub_selects = []
sub_params = []
for index, (select, _, alias) in enumerate(self.select, start=1):
if not alias and with_col_aliases:
alias = 'col%d' % index
if alias:
sub_selects.append("%s.%s" % (
self.connection.ops.quote_name('subquery'),
self.connection.ops.quote_name(alias),
))
else:
select_clone = select.relabeled_clone({select.alias: 'subquery'})
subselect, subparams = select_clone.as_sql(self, self.connection)
sub_selects.append(subselect)
sub_params.extend(subparams)
return 'SELECT %s FROM (%s) subquery' % (
', '.join(sub_selects),
' '.join(result),
), tuple(sub_params + params)
return ' '.join(result), tuple(params)
finally:
# Finally do cleanup - get rid of the joins we created above.
self.query.reset_refcounts(refcounts_before)
def get_default_columns(self, start_alias=None, opts=None, from_parent=None):
"""
Compute the default columns for selecting every field in the base
model. Will sometimes be called to pull in related models (e.g. via
select_related), in which case "opts" and "start_alias" will be given
to provide a starting point for the traversal.
Return a list of strings, quoted appropriately for use in SQL
directly, as well as a set of aliases used in the select statement (if
'as_pairs' is True, return a list of (alias, col_name) pairs instead
of strings as the first component and None as the second component).
"""
result = []
if opts is None:
opts = self.query.get_meta()
only_load = self.deferred_to_columns()
start_alias = start_alias or self.query.get_initial_alias()
# The 'seen_models' is used to optimize checking the needed parent
# alias for a given field. This also includes None -> start_alias to
# be used by local fields.
seen_models = {None: start_alias}
for field in opts.concrete_fields:
model = field.model._meta.concrete_model
# A proxy model will have a different model and concrete_model. We
# will assign None if the field belongs to this model.
if model == opts.model:
model = None
if from_parent and model is not None and issubclass(
from_parent._meta.concrete_model, model._meta.concrete_model):
# Avoid loading data for already loaded parents.
# We end up here in the case select_related() resolution
# proceeds from parent model to child model. In that case the
# parent model data is already present in the SELECT clause,
# and we want to avoid reloading the same data again.
continue
if field.model in only_load and field.attname not in only_load[field.model]:
continue
alias = self.query.join_parent_model(opts, model, start_alias,
seen_models)
column = field.get_col(alias)
result.append(column)
return result
def get_distinct(self):
"""
Return a quoted list of fields to use in DISTINCT ON part of the query.
This method can alter the tables in the query, and thus it must be
called before get_from_clause().
"""
result = []
params = []
opts = self.query.get_meta()
for name in self.query.distinct_fields:
parts = name.split(LOOKUP_SEP)
_, targets, alias, joins, path, _, transform_function = self._setup_joins(parts, opts, None)
targets, alias, _ = self.query.trim_joins(targets, joins, path)
for target in targets:
if name in self.query.annotation_select:
result.append(name)
else:
r, p = self.compile(transform_function(target, alias))
result.append(r)
params.append(p)
return result, params
def find_ordering_name(self, name, opts, alias=None, default_order='ASC',
already_seen=None):
"""
Return the table alias (the name might be ambiguous, the alias will
not be) and column name for ordering by the given 'name' parameter.
The 'name' is of the form 'field1__field2__...__fieldN'.
"""
name, order = get_order_dir(name, default_order)
descending = order == 'DESC'
pieces = name.split(LOOKUP_SEP)
field, targets, alias, joins, path, opts, transform_function = self._setup_joins(pieces, opts, alias)
# If we get to this point and the field is a relation to another model,
# append the default ordering for that model unless it is the pk
# shortcut or the attribute name of the field that is specified.
if field.is_relation and opts.ordering and getattr(field, 'attname', None) != name and name != 'pk':
# Firstly, avoid infinite loops.
already_seen = already_seen or set()
join_tuple = tuple(getattr(self.query.alias_map[j], 'join_cols', None) for j in joins)
if join_tuple in already_seen:
raise FieldError('Infinite loop caused by ordering.')
already_seen.add(join_tuple)
results = []
for item in opts.ordering:
if hasattr(item, 'resolve_expression') and not isinstance(item, OrderBy):
item = item.desc() if descending else item.asc()
if isinstance(item, OrderBy):
results.append((item, False))
continue
results.extend(self.find_ordering_name(item, opts, alias,
order, already_seen))
return results
targets, alias, _ = self.query.trim_joins(targets, joins, path)
return [(OrderBy(transform_function(t, alias), descending=descending), False) for t in targets]
def _setup_joins(self, pieces, opts, alias):
"""
Helper method for get_order_by() and get_distinct().
get_ordering() and get_distinct() must produce same target columns on
same input, as the prefixes of get_ordering() and get_distinct() must
match. Executing SQL where this is not true is an error.
"""
alias = alias or self.query.get_initial_alias()
field, targets, opts, joins, path, transform_function = self.query.setup_joins(pieces, opts, alias)
alias = joins[-1]
return field, targets, alias, joins, path, opts, transform_function
def get_from_clause(self):
"""
Return a list of strings that are joined together to go after the
"FROM" part of the query, as well as a list any extra parameters that
need to be included. Subclasses, can override this to create a
from-clause via a "select".
This should only be called after any SQL construction methods that
might change the tables that are needed. This means the select columns,
ordering, and distinct must be done first.
"""
result = []
params = []
for alias in tuple(self.query.alias_map):
if not self.query.alias_refcount[alias]:
continue
try:
from_clause = self.query.alias_map[alias]
except KeyError:
# Extra tables can end up in self.tables, but not in the
# alias_map if they aren't in a join. That's OK. We skip them.
continue
clause_sql, clause_params = self.compile(from_clause)
result.append(clause_sql)
params.extend(clause_params)
for t in self.query.extra_tables:
alias, _ = self.query.table_alias(t)
# Only add the alias if it's not already present (the table_alias()
# call increments the refcount, so an alias refcount of one means
# this is the only reference).
if alias not in self.query.alias_map or self.query.alias_refcount[alias] == 1:
result.append(', %s' % self.quote_name_unless_alias(alias))
return result, params
def get_related_selections(self, select, opts=None, root_alias=None, cur_depth=1,
requested=None, restricted=None):
"""
Fill in the information needed for a select_related query. The current
depth is measured as the number of connections away from the root model
(for example, cur_depth=1 means we are looking at models with direct
connections to the root model).
"""
def _get_field_choices():
direct_choices = (f.name for f in opts.fields if f.is_relation)
reverse_choices = (
f.field.related_query_name()
for f in opts.related_objects if f.field.unique
)
return chain(direct_choices, reverse_choices, self.query._filtered_relations)
related_klass_infos = []
if not restricted and cur_depth > self.query.max_depth:
# We've recursed far enough; bail out.
return related_klass_infos
if not opts:
opts = self.query.get_meta()
root_alias = self.query.get_initial_alias()
only_load = self.query.get_loaded_field_names()
# Setup for the case when only particular related fields should be
# included in the related selection.
fields_found = set()
if requested is None:
restricted = isinstance(self.query.select_related, dict)
if restricted:
requested = self.query.select_related
def get_related_klass_infos(klass_info, related_klass_infos):
klass_info['related_klass_infos'] = related_klass_infos
for f in opts.fields:
field_model = f.model._meta.concrete_model
fields_found.add(f.name)
if restricted:
next = requested.get(f.name, {})
if not f.is_relation:
# If a non-related field is used like a relation,
# or if a single non-relational field is given.
if next or f.name in requested:
raise FieldError(
"Non-relational field given in select_related: '%s'. "
"Choices are: %s" % (
f.name,
", ".join(_get_field_choices()) or '(none)',
)
)
else:
next = False
if not select_related_descend(f, restricted, requested,
only_load.get(field_model)):
continue
klass_info = {
'model': f.remote_field.model,
'field': f,
'reverse': False,
'local_setter': f.set_cached_value,
'remote_setter': f.remote_field.set_cached_value if f.unique else lambda x, y: None,
'from_parent': False,
}
related_klass_infos.append(klass_info)
select_fields = []
_, _, _, joins, _, _ = self.query.setup_joins(
[f.name], opts, root_alias)
alias = joins[-1]
columns = self.get_default_columns(start_alias=alias, opts=f.remote_field.model._meta)
for col in columns:
select_fields.append(len(select))
select.append((col, None))
klass_info['select_fields'] = select_fields
next_klass_infos = self.get_related_selections(
select, f.remote_field.model._meta, alias, cur_depth + 1, next, restricted)
get_related_klass_infos(klass_info, next_klass_infos)
if restricted:
related_fields = [
(o.field, o.related_model)
for o in opts.related_objects
if o.field.unique and not o.many_to_many
]
for f, model in related_fields:
if not select_related_descend(f, restricted, requested,
only_load.get(model), reverse=True):
continue
related_field_name = f.related_query_name()
fields_found.add(related_field_name)
join_info = self.query.setup_joins([related_field_name], opts, root_alias)
alias = join_info.joins[-1]
from_parent = issubclass(model, opts.model) and model is not opts.model
klass_info = {
'model': model,
'field': f,
'reverse': True,
'local_setter': f.remote_field.set_cached_value,
'remote_setter': f.set_cached_value,
'from_parent': from_parent,
}
related_klass_infos.append(klass_info)
select_fields = []
columns = self.get_default_columns(
start_alias=alias, opts=model._meta, from_parent=opts.model)
for col in columns:
select_fields.append(len(select))
select.append((col, None))
klass_info['select_fields'] = select_fields
next = requested.get(f.related_query_name(), {})
next_klass_infos = self.get_related_selections(
select, model._meta, alias, cur_depth + 1,
next, restricted)
get_related_klass_infos(klass_info, next_klass_infos)
def local_setter(obj, from_obj):
# Set a reverse fk object when relation is non-empty.
if from_obj:
f.remote_field.set_cached_value(from_obj, obj)
def remote_setter(name, obj, from_obj):
setattr(from_obj, name, obj)
for name in list(requested):
# Filtered relations work only on the topmost level.
if cur_depth > 1:
break
if name in self.query._filtered_relations:
fields_found.add(name)
f, _, join_opts, joins, _, _ = self.query.setup_joins([name], opts, root_alias)
model = join_opts.model
alias = joins[-1]
from_parent = issubclass(model, opts.model) and model is not opts.model
klass_info = {
'model': model,
'field': f,
'reverse': True,
'local_setter': local_setter,
'remote_setter': partial(remote_setter, name),
'from_parent': from_parent,
}
related_klass_infos.append(klass_info)
select_fields = []
columns = self.get_default_columns(
start_alias=alias, opts=model._meta,
from_parent=opts.model,
)
for col in columns:
select_fields.append(len(select))
select.append((col, None))
klass_info['select_fields'] = select_fields
next_requested = requested.get(name, {})
next_klass_infos = self.get_related_selections(
select, opts=model._meta, root_alias=alias,
cur_depth=cur_depth + 1, requested=next_requested,
restricted=restricted,
)
get_related_klass_infos(klass_info, next_klass_infos)
fields_not_found = set(requested).difference(fields_found)
if fields_not_found:
invalid_fields = ("'%s'" % s for s in fields_not_found)
raise FieldError(
'Invalid field name(s) given in select_related: %s. '
'Choices are: %s' % (
', '.join(invalid_fields),
', '.join(_get_field_choices()) or '(none)',
)
)
return related_klass_infos
def get_select_for_update_of_arguments(self):
"""
Return a quoted list of arguments for the SELECT FOR UPDATE OF part of
the query.
"""
def _get_parent_klass_info(klass_info):
for parent_model, parent_link in klass_info['model']._meta.parents.items():
parent_list = parent_model._meta.get_parent_list()
yield {
'model': parent_model,
'field': parent_link,
'reverse': False,
'select_fields': [
select_index
for select_index in klass_info['select_fields']
# Selected columns from a model or its parents.
if (
self.select[select_index][0].target.model == parent_model or
self.select[select_index][0].target.model in parent_list
)
],
}
def _get_first_selected_col_from_model(klass_info):
"""
Find the first selected column from a model. If it doesn't exist,
don't lock a model.
select_fields is filled recursively, so it also contains fields
from the parent models.
"""
for select_index in klass_info['select_fields']:
if self.select[select_index][0].target.model == klass_info['model']:
return self.select[select_index][0]
def _get_field_choices():
"""Yield all allowed field paths in breadth-first search order."""
queue = collections.deque([(None, self.klass_info)])
while queue:
parent_path, klass_info = queue.popleft()
if parent_path is None:
path = []
yield 'self'
else:
field = klass_info['field']
if klass_info['reverse']:
field = field.remote_field
path = parent_path + [field.name]
yield LOOKUP_SEP.join(path)
queue.extend(
(path, klass_info)
for klass_info in _get_parent_klass_info(klass_info)
)
queue.extend(
(path, klass_info)
for klass_info in klass_info.get('related_klass_infos', [])
)
result = []
invalid_names = []
for name in self.query.select_for_update_of:
klass_info = self.klass_info
if name == 'self':
col = _get_first_selected_col_from_model(klass_info)
else:
for part in name.split(LOOKUP_SEP):
klass_infos = (
*klass_info.get('related_klass_infos', []),
*_get_parent_klass_info(klass_info),
)
for related_klass_info in klass_infos:
field = related_klass_info['field']
if related_klass_info['reverse']:
field = field.remote_field
if field.name == part:
klass_info = related_klass_info
break
else:
klass_info = None
break
if klass_info is None:
invalid_names.append(name)
continue
col = _get_first_selected_col_from_model(klass_info)
if col is not None:
if self.connection.features.select_for_update_of_column:
result.append(self.compile(col)[0])
else:
result.append(self.quote_name_unless_alias(col.alias))
if invalid_names:
raise FieldError(
'Invalid field name(s) given in select_for_update(of=(...)): %s. '
'Only relational fields followed in the query are allowed. '
'Choices are: %s.' % (
', '.join(invalid_names),
', '.join(_get_field_choices()),
)
)
return result
def deferred_to_columns(self):
"""
Convert the self.deferred_loading data structure to mapping of table
names to sets of column names which are to be loaded. Return the
dictionary.
"""
columns = {}
self.query.deferred_to_data(columns, self.query.get_loaded_field_names_cb)
return columns
def get_converters(self, expressions):
converters = {}
for i, expression in enumerate(expressions):
if expression:
backend_converters = self.connection.ops.get_db_converters(expression)
field_converters = expression.get_db_converters(self.connection)
if backend_converters or field_converters:
converters[i] = (backend_converters + field_converters, expression)
return converters
def apply_converters(self, rows, converters):
connection = self.connection
converters = list(converters.items())
for row in map(list, rows):
for pos, (convs, expression) in converters:
value = row[pos]
for converter in convs:
value = converter(value, expression, connection)
row[pos] = value
yield row
def results_iter(self, results=None, tuple_expected=False, chunked_fetch=False,
chunk_size=GET_ITERATOR_CHUNK_SIZE):
"""Return an iterator over the results from executing this query."""
if results is None:
results = self.execute_sql(MULTI, chunked_fetch=chunked_fetch, chunk_size=chunk_size)
fields = [s[0] for s in self.select[0:self.col_count]]
converters = self.get_converters(fields)
rows = chain.from_iterable(results)
if converters:
rows = self.apply_converters(rows, converters)
if tuple_expected:
rows = map(tuple, rows)
return rows
def has_results(self):
"""
Backends (e.g. NoSQL) can override this in order to use optimized
versions of "query has any results."
"""
# This is always executed on a query clone, so we can modify self.query
self.query.add_extra({'a': 1}, None, None, None, None, None)
self.query.set_extra_mask(['a'])
return bool(self.execute_sql(SINGLE))
def execute_sql(self, result_type=MULTI, chunked_fetch=False, chunk_size=GET_ITERATOR_CHUNK_SIZE):
"""
Run the query against the database and return the result(s). The
return value is a single data item if result_type is SINGLE, or an
iterator over the results if the result_type is MULTI.
result_type is either MULTI (use fetchmany() to retrieve all rows),
SINGLE (only retrieve a single row), or None. In this last case, the
cursor is returned if any query is executed, since it's used by
subclasses such as InsertQuery). It's possible, however, that no query
is needed, as the filters describe an empty set. In that case, None is
returned, to avoid any unnecessary database interaction.
"""
result_type = result_type or NO_RESULTS
try:
sql, params = self.as_sql()
if not sql:
raise EmptyResultSet
except EmptyResultSet:
if result_type == MULTI:
return iter([])
else:
return
if chunked_fetch:
cursor = self.connection.chunked_cursor()
else:
cursor = self.connection.cursor()
try:
cursor.execute(sql, params)
except Exception:
# Might fail for server-side cursors (e.g. connection closed)
cursor.close()
raise
if result_type == CURSOR:
# Give the caller the cursor to process and close.
return cursor
if result_type == SINGLE:
try:
val = cursor.fetchone()
if val:
return val[0:self.col_count]
return val
finally:
# done with the cursor
cursor.close()
if result_type == NO_RESULTS:
cursor.close()
return
result = cursor_iter(
cursor, self.connection.features.empty_fetchmany_value,
self.col_count if self.has_extra_select else None,
chunk_size,
)
if not chunked_fetch or not self.connection.features.can_use_chunked_reads:
try:
# If we are using non-chunked reads, we return the same data
# structure as normally, but ensure it is all read into memory
# before going any further. Use chunked_fetch if requested,
# unless the database doesn't support it.
return list(result)
finally:
# done with the cursor
cursor.close()
return result
def as_subquery_condition(self, alias, columns, compiler):
qn = compiler.quote_name_unless_alias
qn2 = self.connection.ops.quote_name
for index, select_col in enumerate(self.query.select):
lhs_sql, lhs_params = self.compile(select_col)
rhs = '%s.%s' % (qn(alias), qn2(columns[index]))
self.query.where.add(
RawSQL('%s = %s' % (lhs_sql, rhs), lhs_params), 'AND')
sql, params = self.as_sql()
return 'EXISTS (%s)' % sql, params
def explain_query(self):
result = list(self.execute_sql())
# Some backends return 1 item tuples with strings, and others return
# tuples with integers and strings. Flatten them out into strings.
for row in result[0]:
if not isinstance(row, str):
yield ' '.join(str(c) for c in row)
else:
yield row
class SQLInsertCompiler(SQLCompiler):
returning_fields = None
returning_params = tuple()
def field_as_sql(self, field, val):
"""
Take a field and a value intended to be saved on that field, and
return placeholder SQL and accompanying params. Check for raw values,
expressions, and fields with get_placeholder() defined in that order.
When field is None, consider the value raw and use it as the
placeholder, with no corresponding parameters returned.
"""
if field is None:
# A field value of None means the value is raw.
sql, params = val, []
elif hasattr(val, 'as_sql'):
# This is an expression, let's compile it.
sql, params = self.compile(val)
elif hasattr(field, 'get_placeholder'):
# Some fields (e.g. geo fields) need special munging before
# they can be inserted.
sql, params = field.get_placeholder(val, self, self.connection), [val]
else:
# Return the common case for the placeholder
sql, params = '%s', [val]
# The following hook is only used by Oracle Spatial, which sometimes
# needs to yield 'NULL' and [] as its placeholder and params instead
# of '%s' and [None]. The 'NULL' placeholder is produced earlier by
# OracleOperations.get_geom_placeholder(). The following line removes
# the corresponding None parameter. See ticket #10888.
params = self.connection.ops.modify_insert_params(sql, params)
return sql, params
def prepare_value(self, field, value):
"""
Prepare a value to be used in a query by resolving it if it is an
expression and otherwise calling the field's get_db_prep_save().
"""
if hasattr(value, 'resolve_expression'):
value = value.resolve_expression(self.query, allow_joins=False, for_save=True)
# Don't allow values containing Col expressions. They refer to
# existing columns on a row, but in the case of insert the row
# doesn't exist yet.
if value.contains_column_references:
raise ValueError(
'Failed to insert expression "%s" on %s. F() expressions '
'can only be used to update, not to insert.' % (value, field)
)
if value.contains_aggregate:
raise FieldError(
'Aggregate functions are not allowed in this query '
'(%s=%r).' % (field.name, value)
)
if value.contains_over_clause:
raise FieldError(
'Window expressions are not allowed in this query (%s=%r).'
% (field.name, value)
)
else:
value = field.get_db_prep_save(value, connection=self.connection)
return value
def pre_save_val(self, field, obj):
"""
Get the given field's value off the given obj. pre_save() is used for
things like auto_now on DateTimeField. Skip it if this is a raw query.
"""
if self.query.raw:
return getattr(obj, field.attname)
return field.pre_save(obj, add=True)
def assemble_as_sql(self, fields, value_rows):
"""
Take a sequence of N fields and a sequence of M rows of values, and
generate placeholder SQL and parameters for each field and value.
Return a pair containing:
* a sequence of M rows of N SQL placeholder strings, and
* a sequence of M rows of corresponding parameter values.
Each placeholder string may contain any number of '%s' interpolation
strings, and each parameter row will contain exactly as many params
as the total number of '%s's in the corresponding placeholder row.
"""
if not value_rows:
return [], []
# list of (sql, [params]) tuples for each object to be saved
# Shape: [n_objs][n_fields][2]
rows_of_fields_as_sql = (
(self.field_as_sql(field, v) for field, v in zip(fields, row))
for row in value_rows
)
# tuple like ([sqls], [[params]s]) for each object to be saved
# Shape: [n_objs][2][n_fields]
sql_and_param_pair_rows = (zip(*row) for row in rows_of_fields_as_sql)
# Extract separate lists for placeholders and params.
# Each of these has shape [n_objs][n_fields]
placeholder_rows, param_rows = zip(*sql_and_param_pair_rows)
# Params for each field are still lists, and need to be flattened.
param_rows = [[p for ps in row for p in ps] for row in param_rows]
return placeholder_rows, param_rows
def as_sql(self):
# We don't need quote_name_unless_alias() here, since these are all
# going to be column names (so we can avoid the extra overhead).
qn = self.connection.ops.quote_name
opts = self.query.get_meta()
insert_statement = self.connection.ops.insert_statement(ignore_conflicts=self.query.ignore_conflicts)
result = ['%s %s' % (insert_statement, qn(opts.db_table))]
fields = self.query.fields or [opts.pk]
result.append('(%s)' % ', '.join(qn(f.column) for f in fields))
if self.query.fields:
value_rows = [
[self.prepare_value(field, self.pre_save_val(field, obj)) for field in fields]
for obj in self.query.objs
]
else:
# An empty object.
value_rows = [[self.connection.ops.pk_default_value()] for _ in self.query.objs]
fields = [None]
# Currently the backends just accept values when generating bulk
# queries and generate their own placeholders. Doing that isn't
# necessary and it should be possible to use placeholders and
# expressions in bulk inserts too.
can_bulk = (not self.returning_fields and self.connection.features.has_bulk_insert)
placeholder_rows, param_rows = self.assemble_as_sql(fields, value_rows)
ignore_conflicts_suffix_sql = self.connection.ops.ignore_conflicts_suffix_sql(
ignore_conflicts=self.query.ignore_conflicts
)
if self.returning_fields and self.connection.features.can_return_columns_from_insert:
if self.connection.features.can_return_rows_from_bulk_insert:
result.append(self.connection.ops.bulk_insert_sql(fields, placeholder_rows))
params = param_rows
else:
result.append("VALUES (%s)" % ", ".join(placeholder_rows[0]))
params = [param_rows[0]]
if ignore_conflicts_suffix_sql:
result.append(ignore_conflicts_suffix_sql)
# Skip empty r_sql to allow subclasses to customize behavior for
# 3rd party backends. Refs #19096.
r_sql, self.returning_params = self.connection.ops.return_insert_columns(self.returning_fields)
if r_sql:
result.append(r_sql)
params += [self.returning_params]
return [(" ".join(result), tuple(chain.from_iterable(params)))]
if can_bulk:
result.append(self.connection.ops.bulk_insert_sql(fields, placeholder_rows))
if ignore_conflicts_suffix_sql:
result.append(ignore_conflicts_suffix_sql)
return [(" ".join(result), tuple(p for ps in param_rows for p in ps))]
else:
if ignore_conflicts_suffix_sql:
result.append(ignore_conflicts_suffix_sql)
return [
(" ".join(result + ["VALUES (%s)" % ", ".join(p)]), vals)
for p, vals in zip(placeholder_rows, param_rows)
]
def execute_sql(self, returning_fields=None):
assert not (
returning_fields and len(self.query.objs) != 1 and
not self.connection.features.can_return_rows_from_bulk_insert
)
self.returning_fields = returning_fields
with self.connection.cursor() as cursor:
for sql, params in self.as_sql():
cursor.execute(sql, params)
if not self.returning_fields:
return []
if self.connection.features.can_return_rows_from_bulk_insert and len(self.query.objs) > 1:
return self.connection.ops.fetch_returned_insert_rows(cursor)
if self.connection.features.can_return_columns_from_insert:
assert len(self.query.objs) == 1
return [self.connection.ops.fetch_returned_insert_columns(cursor, self.returning_params)]
return [(self.connection.ops.last_insert_id(
cursor, self.query.get_meta().db_table, self.query.get_meta().pk.column
),)]
class SQLDeleteCompiler(SQLCompiler):
@cached_property
def single_alias(self):
return sum(self.query.alias_refcount[t] > 0 for t in self.query.alias_map) == 1
def _as_sql(self, query):
result = [
'DELETE FROM %s' % self.quote_name_unless_alias(query.base_table)
]
where, params = self.compile(query.where)
if where:
result.append('WHERE %s' % where)
return ' '.join(result), tuple(params)
def as_sql(self):
"""
Create the SQL for this query. Return the SQL string and list of
parameters.
"""
if self.single_alias:
return self._as_sql(self.query)
innerq = self.query.clone()
innerq.__class__ = Query
innerq.clear_select_clause()
pk = self.query.model._meta.pk
innerq.select = [
pk.get_col(self.query.get_initial_alias())
]
outerq = Query(self.query.model)
outerq.where = self.query.where_class()
outerq.add_q(Q(pk__in=innerq))
return self._as_sql(outerq)
class SQLUpdateCompiler(SQLCompiler):
def as_sql(self):
"""
Create the SQL for this query. Return the SQL string and list of
parameters.
"""
self.pre_sql_setup()
if not self.query.values:
return '', ()
qn = self.quote_name_unless_alias
values, update_params = [], []
for field, model, val in self.query.values:
if hasattr(val, 'resolve_expression'):
val = val.resolve_expression(self.query, allow_joins=False, for_save=True)
if val.contains_aggregate:
raise FieldError(
'Aggregate functions are not allowed in this query '
'(%s=%r).' % (field.name, val)
)
if val.contains_over_clause:
raise FieldError(
'Window expressions are not allowed in this query '
'(%s=%r).' % (field.name, val)
)
elif hasattr(val, 'prepare_database_save'):
if field.remote_field:
val = field.get_db_prep_save(
val.prepare_database_save(field),
connection=self.connection,
)
else:
raise TypeError(
"Tried to update field %s with a model instance, %r. "
"Use a value compatible with %s."
% (field, val, field.__class__.__name__)
)
else:
val = field.get_db_prep_save(val, connection=self.connection)
# Getting the placeholder for the field.
if hasattr(field, 'get_placeholder'):
placeholder = field.get_placeholder(val, self, self.connection)
else:
placeholder = '%s'
name = field.column
if hasattr(val, 'as_sql'):
sql, params = self.compile(val)
values.append('%s = %s' % (qn(name), placeholder % sql))
update_params.extend(params)
elif val is not None:
values.append('%s = %s' % (qn(name), placeholder))
update_params.append(val)
else:
values.append('%s = NULL' % qn(name))
table = self.query.base_table
result = [
'UPDATE %s SET' % qn(table),
', '.join(values),
]
where, params = self.compile(self.query.where)
if where:
result.append('WHERE %s' % where)
return ' '.join(result), tuple(update_params + params)
def execute_sql(self, result_type):
"""
Execute the specified update. Return the number of rows affected by
the primary update query. The "primary update query" is the first
non-empty query that is executed. Row counts for any subsequent,
related queries are not available.
"""
cursor = super().execute_sql(result_type)
try:
rows = cursor.rowcount if cursor else 0
is_empty = cursor is None
finally:
if cursor:
cursor.close()
for query in self.query.get_related_updates():
aux_rows = query.get_compiler(self.using).execute_sql(result_type)
if is_empty and aux_rows:
rows = aux_rows
is_empty = False
return rows
def pre_sql_setup(self):
"""
If the update depends on results from other tables, munge the "where"
conditions to match the format required for (portable) SQL updates.
If multiple updates are required, pull out the id values to update at
this point so that they don't change as a result of the progressive
updates.
"""
refcounts_before = self.query.alias_refcount.copy()
# Ensure base table is in the query
self.query.get_initial_alias()
count = self.query.count_active_tables()
if not self.query.related_updates and count == 1:
return
query = self.query.chain(klass=Query)
query.select_related = False
query.clear_ordering(True)
query.extra = {}
query.select = []
query.add_fields([query.get_meta().pk.name])
super().pre_sql_setup()
must_pre_select = count > 1 and not self.connection.features.update_can_self_select
# Now we adjust the current query: reset the where clause and get rid
# of all the tables we don't need (since they're in the sub-select).
self.query.where = self.query.where_class()
if self.query.related_updates or must_pre_select:
# Either we're using the idents in multiple update queries (so
# don't want them to change), or the db backend doesn't support
# selecting from the updating table (e.g. MySQL).
idents = []
for rows in query.get_compiler(self.using).execute_sql(MULTI):
idents.extend(r[0] for r in rows)
self.query.add_filter(('pk__in', idents))
self.query.related_ids = idents
else:
# The fast path. Filters and updates in one query.
self.query.add_filter(('pk__in', query))
self.query.reset_refcounts(refcounts_before)
class SQLAggregateCompiler(SQLCompiler):
def as_sql(self):
"""
Create the SQL for this query. Return the SQL string and list of
parameters.
"""
sql, params = [], []
for annotation in self.query.annotation_select.values():
ann_sql, ann_params = self.compile(annotation)
ann_sql, ann_params = annotation.select_format(self, ann_sql, ann_params)
sql.append(ann_sql)
params.extend(ann_params)
self.col_count = len(self.query.annotation_select)
sql = ', '.join(sql)
params = tuple(params)
sql = 'SELECT %s FROM (%s) subquery' % (sql, self.query.subquery)
params = params + self.query.sub_params
return sql, params
def cursor_iter(cursor, sentinel, col_count, itersize):
"""
Yield blocks of rows from a cursor and ensure the cursor is closed when
done.
"""
try:
for rows in iter((lambda: cursor.fetchmany(itersize)), sentinel):
yield rows if col_count is None else [r[:col_count] for r in rows]
finally:
cursor.close()
|
d2dec86d2b14481fd123362e997386f2a044bfacbdf6229385502f168c23018d | """
Constants specific to the SQL storage portion of the ORM.
"""
# Size of each "chunk" for get_iterator calls.
# Larger values are slightly faster at the expense of more storage space.
GET_ITERATOR_CHUNK_SIZE = 100
# Namedtuples for sql.* internal use.
# How many results to expect from a cursor.execute call
MULTI = 'multi'
SINGLE = 'single'
CURSOR = 'cursor'
NO_RESULTS = 'no results'
ORDER_DIR = {
'ASC': ('ASC', 'DESC'),
'DESC': ('DESC', 'ASC'),
}
# SQL join types.
INNER = 'INNER JOIN'
LOUTER = 'LEFT OUTER JOIN'
|
36d71cf7ecf77abc475a620e2967186a011093ec4f652eebdb45f9895ea082ee | """
Query subclasses which provide extra functionality beyond simple data retrieval.
"""
from django.core.exceptions import FieldError
from django.db.models.query_utils import Q
from django.db.models.sql.constants import (
CURSOR, GET_ITERATOR_CHUNK_SIZE, NO_RESULTS,
)
from django.db.models.sql.query import Query
__all__ = ['DeleteQuery', 'UpdateQuery', 'InsertQuery', 'AggregateQuery']
class DeleteQuery(Query):
"""A DELETE SQL query."""
compiler = 'SQLDeleteCompiler'
def do_query(self, table, where, using):
self.alias_map = {table: self.alias_map[table]}
self.where = where
cursor = self.get_compiler(using).execute_sql(CURSOR)
if cursor:
with cursor:
return cursor.rowcount
return 0
def delete_batch(self, pk_list, using):
"""
Set up and execute delete queries for all the objects in pk_list.
More than one physical query may be executed if there are a
lot of values in pk_list.
"""
# number of objects deleted
num_deleted = 0
field = self.get_meta().pk
for offset in range(0, len(pk_list), GET_ITERATOR_CHUNK_SIZE):
self.where = self.where_class()
self.add_q(Q(
**{field.attname + '__in': pk_list[offset:offset + GET_ITERATOR_CHUNK_SIZE]}))
num_deleted += self.do_query(self.get_meta().db_table, self.where, using=using)
return num_deleted
class UpdateQuery(Query):
"""An UPDATE SQL query."""
compiler = 'SQLUpdateCompiler'
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self._setup_query()
def _setup_query(self):
"""
Run on initialization and at the end of chaining. Any attributes that
would normally be set in __init__() should go here instead.
"""
self.values = []
self.related_ids = None
self.related_updates = {}
def clone(self):
obj = super().clone()
obj.related_updates = self.related_updates.copy()
return obj
def update_batch(self, pk_list, values, using):
self.add_update_values(values)
for offset in range(0, len(pk_list), GET_ITERATOR_CHUNK_SIZE):
self.where = self.where_class()
self.add_q(Q(pk__in=pk_list[offset: offset + GET_ITERATOR_CHUNK_SIZE]))
self.get_compiler(using).execute_sql(NO_RESULTS)
def add_update_values(self, values):
"""
Convert a dictionary of field name to value mappings into an update
query. This is the entry point for the public update() method on
querysets.
"""
values_seq = []
for name, val in values.items():
field = self.get_meta().get_field(name)
direct = not (field.auto_created and not field.concrete) or not field.concrete
model = field.model._meta.concrete_model
if not direct or (field.is_relation and field.many_to_many):
raise FieldError(
'Cannot update model field %r (only non-relations and '
'foreign keys permitted).' % field
)
if model is not self.get_meta().concrete_model:
self.add_related_update(model, field, val)
continue
values_seq.append((field, model, val))
return self.add_update_fields(values_seq)
def add_update_fields(self, values_seq):
"""
Append a sequence of (field, model, value) triples to the internal list
that will be used to generate the UPDATE query. Might be more usefully
called add_update_targets() to hint at the extra information here.
"""
for field, model, val in values_seq:
if hasattr(val, 'resolve_expression'):
# Resolve expressions here so that annotations are no longer needed
val = val.resolve_expression(self, allow_joins=False, for_save=True)
self.values.append((field, model, val))
def add_related_update(self, model, field, value):
"""
Add (name, value) to an update query for an ancestor model.
Update are coalesced so that only one update query per ancestor is run.
"""
self.related_updates.setdefault(model, []).append((field, None, value))
def get_related_updates(self):
"""
Return a list of query objects: one for each update required to an
ancestor model. Each query will have the same filtering conditions as
the current query but will only update a single table.
"""
if not self.related_updates:
return []
result = []
for model, values in self.related_updates.items():
query = UpdateQuery(model)
query.values = values
if self.related_ids is not None:
query.add_filter(('pk__in', self.related_ids))
result.append(query)
return result
class InsertQuery(Query):
compiler = 'SQLInsertCompiler'
def __init__(self, *args, ignore_conflicts=False, **kwargs):
super().__init__(*args, **kwargs)
self.fields = []
self.objs = []
self.ignore_conflicts = ignore_conflicts
def insert_values(self, fields, objs, raw=False):
self.fields = fields
self.objs = objs
self.raw = raw
class AggregateQuery(Query):
"""
Take another query as a parameter to the FROM clause and only select the
elements in the provided list.
"""
compiler = 'SQLAggregateCompiler'
def add_subquery(self, query, using):
query.subquery = True
self.subquery, self.sub_params = query.get_compiler(using).as_sql(with_col_aliases=True)
|
00c3e6e47842a13373ca0f1cfcc350b6d431e39c2c53b6703d86042c3b0443e2 | from django.db import InterfaceError
from django.db.backends.base.features import BaseDatabaseFeatures
class DatabaseFeatures(BaseDatabaseFeatures):
interprets_empty_strings_as_nulls = True
has_select_for_update = True
has_select_for_update_nowait = True
has_select_for_update_skip_locked = True
has_select_for_update_of = True
select_for_update_of_column = True
can_return_columns_from_insert = True
can_introspect_autofield = True
supports_subqueries_in_group_by = False
supports_transactions = True
supports_timezones = False
has_native_duration_field = True
can_defer_constraint_checks = True
supports_partially_nullable_unique_constraints = False
supports_deferrable_unique_constraints = True
truncates_names = True
supports_tablespaces = True
supports_sequence_reset = False
can_introspect_materialized_views = True
can_introspect_time_field = False
atomic_transactions = False
supports_combined_alters = False
nulls_order_largest = True
requires_literal_defaults = True
closed_cursor_error_class = InterfaceError
bare_select_suffix = " FROM DUAL"
# select for update with limit can be achieved on Oracle, but not with the current backend.
supports_select_for_update_with_limit = False
supports_temporal_subtraction = True
# Oracle doesn't ignore quoted identifiers case but the current backend
# does by uppercasing all identifiers.
ignores_table_name_case = True
supports_index_on_text_field = False
has_case_insensitive_like = False
create_test_procedure_without_params_sql = """
CREATE PROCEDURE "TEST_PROCEDURE" AS
V_I INTEGER;
BEGIN
V_I := 1;
END;
"""
create_test_procedure_with_int_param_sql = """
CREATE PROCEDURE "TEST_PROCEDURE" (P_I INTEGER) AS
V_I INTEGER;
BEGIN
V_I := P_I;
END;
"""
supports_callproc_kwargs = True
supports_over_clause = True
supports_frame_range_fixed_distance = True
supports_ignore_conflicts = False
max_query_params = 2**16 - 1
supports_partial_indexes = False
supports_slicing_ordering_in_compound = True
allows_multiple_constraints_on_same_fields = False
supports_boolean_expr_in_select_clause = False
supports_primitives_in_json_field = False
|
d51ac09b91e6b414656999d1da135dd68affbda0e4cf98c94dbee953989f11d9 | from collections import namedtuple
import cx_Oracle
from django.db import models
from django.db.backends.base.introspection import (
BaseDatabaseIntrospection, FieldInfo as BaseFieldInfo, TableInfo,
)
FieldInfo = namedtuple('FieldInfo', BaseFieldInfo._fields + ('is_autofield', 'is_json'))
class DatabaseIntrospection(BaseDatabaseIntrospection):
# Maps type objects to Django Field types.
data_types_reverse = {
cx_Oracle.BLOB: 'BinaryField',
cx_Oracle.CLOB: 'TextField',
cx_Oracle.DATETIME: 'DateField',
cx_Oracle.FIXED_CHAR: 'CharField',
cx_Oracle.FIXED_NCHAR: 'CharField',
cx_Oracle.INTERVAL: 'DurationField',
cx_Oracle.NATIVE_FLOAT: 'FloatField',
cx_Oracle.NCHAR: 'CharField',
cx_Oracle.NCLOB: 'TextField',
cx_Oracle.NUMBER: 'DecimalField',
cx_Oracle.STRING: 'CharField',
cx_Oracle.TIMESTAMP: 'DateTimeField',
}
cache_bust_counter = 1
def get_field_type(self, data_type, description):
if data_type == cx_Oracle.NUMBER:
precision, scale = description[4:6]
if scale == 0:
if precision > 11:
return 'BigAutoField' if description.is_autofield else 'BigIntegerField'
elif 1 < precision < 6 and description.is_autofield:
return 'SmallAutoField'
elif precision == 1:
return 'BooleanField'
elif description.is_autofield:
return 'AutoField'
else:
return 'IntegerField'
elif scale == -127:
return 'FloatField'
elif data_type == cx_Oracle.NCLOB and description.is_json:
return 'JSONField'
return super().get_field_type(data_type, description)
def get_table_list(self, cursor):
"""Return a list of table and view names in the current database."""
cursor.execute("""
SELECT table_name, 't'
FROM user_tables
WHERE
NOT EXISTS (
SELECT 1
FROM user_mviews
WHERE user_mviews.mview_name = user_tables.table_name
)
UNION ALL
SELECT view_name, 'v' FROM user_views
UNION ALL
SELECT mview_name, 'v' FROM user_mviews
""")
return [TableInfo(self.identifier_converter(row[0]), row[1]) for row in cursor.fetchall()]
def get_table_description(self, cursor, table_name):
"""
Return a description of the table with the DB-API cursor.description
interface.
"""
# user_tab_columns gives data default for columns
cursor.execute("""
SELECT
column_name,
data_default,
CASE
WHEN char_used IS NULL THEN data_length
ELSE char_length
END as internal_size,
CASE
WHEN identity_column = 'YES' THEN 1
ELSE 0
END as is_autofield,
CASE
WHEN EXISTS (
SELECT 1
FROM user_json_columns
WHERE
user_json_columns.table_name = user_tab_cols.table_name AND
user_json_columns.column_name = user_tab_cols.column_name
)
THEN 1
ELSE 0
END as is_json
FROM user_tab_cols
WHERE table_name = UPPER(%s)""", [table_name])
field_map = {
column: (internal_size, default if default != 'NULL' else None, is_autofield, is_json)
for column, default, internal_size, is_autofield, is_json in cursor.fetchall()
}
self.cache_bust_counter += 1
cursor.execute("SELECT * FROM {} WHERE ROWNUM < 2 AND {} > 0".format(
self.connection.ops.quote_name(table_name),
self.cache_bust_counter))
description = []
for desc in cursor.description:
name = desc[0]
internal_size, default, is_autofield, is_json = field_map[name]
name = name % {} # cx_Oracle, for some reason, doubles percent signs.
description.append(FieldInfo(
self.identifier_converter(name), *desc[1:3], internal_size, desc[4] or 0,
desc[5] or 0, *desc[6:], default, is_autofield, is_json,
))
return description
def identifier_converter(self, name):
"""Identifier comparison is case insensitive under Oracle."""
return name.lower()
def get_sequences(self, cursor, table_name, table_fields=()):
cursor.execute("""
SELECT
user_tab_identity_cols.sequence_name,
user_tab_identity_cols.column_name
FROM
user_tab_identity_cols,
user_constraints,
user_cons_columns cols
WHERE
user_constraints.constraint_name = cols.constraint_name
AND user_constraints.table_name = user_tab_identity_cols.table_name
AND cols.column_name = user_tab_identity_cols.column_name
AND user_constraints.constraint_type = 'P'
AND user_tab_identity_cols.table_name = UPPER(%s)
""", [table_name])
# Oracle allows only one identity column per table.
row = cursor.fetchone()
if row:
return [{
'name': self.identifier_converter(row[0]),
'table': self.identifier_converter(table_name),
'column': self.identifier_converter(row[1]),
}]
# To keep backward compatibility for AutoFields that aren't Oracle
# identity columns.
for f in table_fields:
if isinstance(f, models.AutoField):
return [{'table': table_name, 'column': f.column}]
return []
def get_relations(self, cursor, table_name):
"""
Return a dictionary of {field_name: (field_name_other_table, other_table)}
representing all relationships to the given table.
"""
table_name = table_name.upper()
cursor.execute("""
SELECT ca.column_name, cb.table_name, cb.column_name
FROM user_constraints, USER_CONS_COLUMNS ca, USER_CONS_COLUMNS cb
WHERE user_constraints.table_name = %s AND
user_constraints.constraint_name = ca.constraint_name AND
user_constraints.r_constraint_name = cb.constraint_name AND
ca.position = cb.position""", [table_name])
return {
self.identifier_converter(field_name): (
self.identifier_converter(rel_field_name),
self.identifier_converter(rel_table_name),
) for field_name, rel_table_name, rel_field_name in cursor.fetchall()
}
def get_key_columns(self, cursor, table_name):
cursor.execute("""
SELECT ccol.column_name, rcol.table_name AS referenced_table, rcol.column_name AS referenced_column
FROM user_constraints c
JOIN user_cons_columns ccol
ON ccol.constraint_name = c.constraint_name
JOIN user_cons_columns rcol
ON rcol.constraint_name = c.r_constraint_name
WHERE c.table_name = %s AND c.constraint_type = 'R'""", [table_name.upper()])
return [
tuple(self.identifier_converter(cell) for cell in row)
for row in cursor.fetchall()
]
def get_primary_key_column(self, cursor, table_name):
cursor.execute("""
SELECT
cols.column_name
FROM
user_constraints,
user_cons_columns cols
WHERE
user_constraints.constraint_name = cols.constraint_name AND
user_constraints.constraint_type = 'P' AND
user_constraints.table_name = UPPER(%s) AND
cols.position = 1
""", [table_name])
row = cursor.fetchone()
return self.identifier_converter(row[0]) if row else None
def get_constraints(self, cursor, table_name):
"""
Retrieve any constraints or keys (unique, pk, fk, check, index) across
one or more columns.
"""
constraints = {}
# Loop over the constraints, getting PKs, uniques, and checks
cursor.execute("""
SELECT
user_constraints.constraint_name,
LISTAGG(LOWER(cols.column_name), ',') WITHIN GROUP (ORDER BY cols.position),
CASE user_constraints.constraint_type
WHEN 'P' THEN 1
ELSE 0
END AS is_primary_key,
CASE
WHEN user_constraints.constraint_type IN ('P', 'U') THEN 1
ELSE 0
END AS is_unique,
CASE user_constraints.constraint_type
WHEN 'C' THEN 1
ELSE 0
END AS is_check_constraint
FROM
user_constraints
LEFT OUTER JOIN
user_cons_columns cols ON user_constraints.constraint_name = cols.constraint_name
WHERE
user_constraints.constraint_type = ANY('P', 'U', 'C')
AND user_constraints.table_name = UPPER(%s)
GROUP BY user_constraints.constraint_name, user_constraints.constraint_type
""", [table_name])
for constraint, columns, pk, unique, check in cursor.fetchall():
constraint = self.identifier_converter(constraint)
constraints[constraint] = {
'columns': columns.split(','),
'primary_key': pk,
'unique': unique,
'foreign_key': None,
'check': check,
'index': unique, # All uniques come with an index
}
# Foreign key constraints
cursor.execute("""
SELECT
cons.constraint_name,
LISTAGG(LOWER(cols.column_name), ',') WITHIN GROUP (ORDER BY cols.position),
LOWER(rcols.table_name),
LOWER(rcols.column_name)
FROM
user_constraints cons
INNER JOIN
user_cons_columns rcols ON rcols.constraint_name = cons.r_constraint_name AND rcols.position = 1
LEFT OUTER JOIN
user_cons_columns cols ON cons.constraint_name = cols.constraint_name
WHERE
cons.constraint_type = 'R' AND
cons.table_name = UPPER(%s)
GROUP BY cons.constraint_name, rcols.table_name, rcols.column_name
""", [table_name])
for constraint, columns, other_table, other_column in cursor.fetchall():
constraint = self.identifier_converter(constraint)
constraints[constraint] = {
'primary_key': False,
'unique': False,
'foreign_key': (other_table, other_column),
'check': False,
'index': False,
'columns': columns.split(','),
}
# Now get indexes
cursor.execute("""
SELECT
ind.index_name,
LOWER(ind.index_type),
LISTAGG(LOWER(cols.column_name), ',') WITHIN GROUP (ORDER BY cols.column_position),
LISTAGG(cols.descend, ',') WITHIN GROUP (ORDER BY cols.column_position)
FROM
user_ind_columns cols, user_indexes ind
WHERE
cols.table_name = UPPER(%s) AND
NOT EXISTS (
SELECT 1
FROM user_constraints cons
WHERE ind.index_name = cons.index_name
) AND cols.index_name = ind.index_name
GROUP BY ind.index_name, ind.index_type
""", [table_name])
for constraint, type_, columns, orders in cursor.fetchall():
constraint = self.identifier_converter(constraint)
constraints[constraint] = {
'primary_key': False,
'unique': False,
'foreign_key': None,
'check': False,
'index': True,
'type': 'idx' if type_ == 'normal' else type_,
'columns': columns.split(','),
'orders': orders.split(','),
}
return constraints
|
07b8e36bb37073a51b816120276da7c02b2429b2c47a621dc38d17a76aa7d625 | """
Oracle database backend for Django.
Requires cx_Oracle: https://oracle.github.io/python-cx_Oracle/
"""
import datetime
import decimal
import os
import platform
from contextlib import contextmanager
from django.conf import settings
from django.core.exceptions import ImproperlyConfigured
from django.db import IntegrityError
from django.db.backends.base.base import BaseDatabaseWrapper
from django.utils.asyncio import async_unsafe
from django.utils.encoding import force_bytes, force_str
from django.utils.functional import cached_property
def _setup_environment(environ):
# Cygwin requires some special voodoo to set the environment variables
# properly so that Oracle will see them.
if platform.system().upper().startswith('CYGWIN'):
try:
import ctypes
except ImportError as e:
raise ImproperlyConfigured("Error loading ctypes: %s; "
"the Oracle backend requires ctypes to "
"operate correctly under Cygwin." % e)
kernel32 = ctypes.CDLL('kernel32')
for name, value in environ:
kernel32.SetEnvironmentVariableA(name, value)
else:
os.environ.update(environ)
_setup_environment([
# Oracle takes client-side character set encoding from the environment.
('NLS_LANG', '.AL32UTF8'),
# This prevents Unicode from getting mangled by getting encoded into the
# potentially non-Unicode database character set.
('ORA_NCHAR_LITERAL_REPLACE', 'TRUE'),
])
try:
import cx_Oracle as Database
except ImportError as e:
raise ImproperlyConfigured("Error loading cx_Oracle module: %s" % e)
# Some of these import cx_Oracle, so import them after checking if it's installed.
from .client import DatabaseClient # NOQA isort:skip
from .creation import DatabaseCreation # NOQA isort:skip
from .features import DatabaseFeatures # NOQA isort:skip
from .introspection import DatabaseIntrospection # NOQA isort:skip
from .operations import DatabaseOperations # NOQA isort:skip
from .schema import DatabaseSchemaEditor # NOQA isort:skip
from .utils import Oracle_datetime # NOQA isort:skip
from .validation import DatabaseValidation # NOQA isort:skip
@contextmanager
def wrap_oracle_errors():
try:
yield
except Database.DatabaseError as e:
# cx_Oracle raises a cx_Oracle.DatabaseError exception with the
# following attributes and values:
# code = 2091
# message = 'ORA-02091: transaction rolled back
# 'ORA-02291: integrity constraint (TEST_DJANGOTEST.SYS
# _C00102056) violated - parent key not found'
# or:
# 'ORA-00001: unique constraint (DJANGOTEST.DEFERRABLE_
# PINK_CONSTRAINT) violated
# Convert that case to Django's IntegrityError exception.
x = e.args[0]
if (
hasattr(x, 'code') and
hasattr(x, 'message') and
x.code == 2091 and
('ORA-02291' in x.message or 'ORA-00001' in x.message)
):
raise IntegrityError(*tuple(e.args))
raise
class _UninitializedOperatorsDescriptor:
def __get__(self, instance, cls=None):
# If connection.operators is looked up before a connection has been
# created, transparently initialize connection.operators to avert an
# AttributeError.
if instance is None:
raise AttributeError("operators not available as class attribute")
# Creating a cursor will initialize the operators.
instance.cursor().close()
return instance.__dict__['operators']
class DatabaseWrapper(BaseDatabaseWrapper):
vendor = 'oracle'
display_name = 'Oracle'
# This dictionary maps Field objects to their associated Oracle column
# types, as strings. Column-type strings can contain format strings; they'll
# be interpolated against the values of Field.__dict__ before being output.
# If a column type is set to None, it won't be included in the output.
#
# Any format strings starting with "qn_" are quoted before being used in the
# output (the "qn_" prefix is stripped before the lookup is performed.
data_types = {
'AutoField': 'NUMBER(11) GENERATED BY DEFAULT ON NULL AS IDENTITY',
'BigAutoField': 'NUMBER(19) GENERATED BY DEFAULT ON NULL AS IDENTITY',
'BinaryField': 'BLOB',
'BooleanField': 'NUMBER(1)',
'CharField': 'NVARCHAR2(%(max_length)s)',
'DateField': 'DATE',
'DateTimeField': 'TIMESTAMP',
'DecimalField': 'NUMBER(%(max_digits)s, %(decimal_places)s)',
'DurationField': 'INTERVAL DAY(9) TO SECOND(6)',
'FileField': 'NVARCHAR2(%(max_length)s)',
'FilePathField': 'NVARCHAR2(%(max_length)s)',
'FloatField': 'DOUBLE PRECISION',
'IntegerField': 'NUMBER(11)',
'JSONField': 'NCLOB',
'BigIntegerField': 'NUMBER(19)',
'IPAddressField': 'VARCHAR2(15)',
'GenericIPAddressField': 'VARCHAR2(39)',
'NullBooleanField': 'NUMBER(1)',
'OneToOneField': 'NUMBER(11)',
'PositiveBigIntegerField': 'NUMBER(19)',
'PositiveIntegerField': 'NUMBER(11)',
'PositiveSmallIntegerField': 'NUMBER(11)',
'SlugField': 'NVARCHAR2(%(max_length)s)',
'SmallAutoField': 'NUMBER(5) GENERATED BY DEFAULT ON NULL AS IDENTITY',
'SmallIntegerField': 'NUMBER(11)',
'TextField': 'NCLOB',
'TimeField': 'TIMESTAMP',
'URLField': 'VARCHAR2(%(max_length)s)',
'UUIDField': 'VARCHAR2(32)',
}
data_type_check_constraints = {
'BooleanField': '%(qn_column)s IN (0,1)',
'JSONField': '%(qn_column)s IS JSON',
'NullBooleanField': '%(qn_column)s IN (0,1)',
'PositiveBigIntegerField': '%(qn_column)s >= 0',
'PositiveIntegerField': '%(qn_column)s >= 0',
'PositiveSmallIntegerField': '%(qn_column)s >= 0',
}
# Oracle doesn't support a database index on these columns.
_limited_data_types = ('clob', 'nclob', 'blob')
operators = _UninitializedOperatorsDescriptor()
_standard_operators = {
'exact': '= %s',
'iexact': '= UPPER(%s)',
'contains': "LIKE TRANSLATE(%s USING NCHAR_CS) ESCAPE TRANSLATE('\\' USING NCHAR_CS)",
'icontains': "LIKE UPPER(TRANSLATE(%s USING NCHAR_CS)) ESCAPE TRANSLATE('\\' USING NCHAR_CS)",
'gt': '> %s',
'gte': '>= %s',
'lt': '< %s',
'lte': '<= %s',
'startswith': "LIKE TRANSLATE(%s USING NCHAR_CS) ESCAPE TRANSLATE('\\' USING NCHAR_CS)",
'endswith': "LIKE TRANSLATE(%s USING NCHAR_CS) ESCAPE TRANSLATE('\\' USING NCHAR_CS)",
'istartswith': "LIKE UPPER(TRANSLATE(%s USING NCHAR_CS)) ESCAPE TRANSLATE('\\' USING NCHAR_CS)",
'iendswith': "LIKE UPPER(TRANSLATE(%s USING NCHAR_CS)) ESCAPE TRANSLATE('\\' USING NCHAR_CS)",
}
_likec_operators = {
**_standard_operators,
'contains': "LIKEC %s ESCAPE '\\'",
'icontains': "LIKEC UPPER(%s) ESCAPE '\\'",
'startswith': "LIKEC %s ESCAPE '\\'",
'endswith': "LIKEC %s ESCAPE '\\'",
'istartswith': "LIKEC UPPER(%s) ESCAPE '\\'",
'iendswith': "LIKEC UPPER(%s) ESCAPE '\\'",
}
# The patterns below are used to generate SQL pattern lookup clauses when
# the right-hand side of the lookup isn't a raw string (it might be an expression
# or the result of a bilateral transformation).
# In those cases, special characters for LIKE operators (e.g. \, %, _)
# should be escaped on the database side.
#
# Note: we use str.format() here for readability as '%' is used as a wildcard for
# the LIKE operator.
pattern_esc = r"REPLACE(REPLACE(REPLACE({}, '\', '\\'), '%%', '\%%'), '_', '\_')"
_pattern_ops = {
'contains': "'%%' || {} || '%%'",
'icontains': "'%%' || UPPER({}) || '%%'",
'startswith': "{} || '%%'",
'istartswith': "UPPER({}) || '%%'",
'endswith': "'%%' || {}",
'iendswith': "'%%' || UPPER({})",
}
_standard_pattern_ops = {k: "LIKE TRANSLATE( " + v + " USING NCHAR_CS)"
" ESCAPE TRANSLATE('\\' USING NCHAR_CS)"
for k, v in _pattern_ops.items()}
_likec_pattern_ops = {k: "LIKEC " + v + " ESCAPE '\\'"
for k, v in _pattern_ops.items()}
Database = Database
SchemaEditorClass = DatabaseSchemaEditor
# Classes instantiated in __init__().
client_class = DatabaseClient
creation_class = DatabaseCreation
features_class = DatabaseFeatures
introspection_class = DatabaseIntrospection
ops_class = DatabaseOperations
validation_class = DatabaseValidation
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
use_returning_into = self.settings_dict["OPTIONS"].get('use_returning_into', True)
self.features.can_return_columns_from_insert = use_returning_into
def _dsn(self):
settings_dict = self.settings_dict
if not settings_dict['HOST'].strip():
settings_dict['HOST'] = 'localhost'
if settings_dict['PORT']:
return Database.makedsn(settings_dict['HOST'], int(settings_dict['PORT']), settings_dict['NAME'])
return settings_dict['NAME']
def _connect_string(self):
return '%s/"%s"@%s' % (self.settings_dict['USER'], self.settings_dict['PASSWORD'], self._dsn())
def get_connection_params(self):
conn_params = self.settings_dict['OPTIONS'].copy()
if 'use_returning_into' in conn_params:
del conn_params['use_returning_into']
return conn_params
@async_unsafe
def get_new_connection(self, conn_params):
return Database.connect(
user=self.settings_dict['USER'],
password=self.settings_dict['PASSWORD'],
dsn=self._dsn(),
**conn_params,
)
def init_connection_state(self):
cursor = self.create_cursor()
# Set the territory first. The territory overrides NLS_DATE_FORMAT
# and NLS_TIMESTAMP_FORMAT to the territory default. When all of
# these are set in single statement it isn't clear what is supposed
# to happen.
cursor.execute("ALTER SESSION SET NLS_TERRITORY = 'AMERICA'")
# Set Oracle date to ANSI date format. This only needs to execute
# once when we create a new connection. We also set the Territory
# to 'AMERICA' which forces Sunday to evaluate to a '1' in
# TO_CHAR().
cursor.execute(
"ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS'"
" NLS_TIMESTAMP_FORMAT = 'YYYY-MM-DD HH24:MI:SS.FF'" +
(" TIME_ZONE = 'UTC'" if settings.USE_TZ else '')
)
cursor.close()
if 'operators' not in self.__dict__:
# Ticket #14149: Check whether our LIKE implementation will
# work for this connection or we need to fall back on LIKEC.
# This check is performed only once per DatabaseWrapper
# instance per thread, since subsequent connections will use
# the same settings.
cursor = self.create_cursor()
try:
cursor.execute("SELECT 1 FROM DUAL WHERE DUMMY %s"
% self._standard_operators['contains'],
['X'])
except Database.DatabaseError:
self.operators = self._likec_operators
self.pattern_ops = self._likec_pattern_ops
else:
self.operators = self._standard_operators
self.pattern_ops = self._standard_pattern_ops
cursor.close()
self.connection.stmtcachesize = 20
# Ensure all changes are preserved even when AUTOCOMMIT is False.
if not self.get_autocommit():
self.commit()
@async_unsafe
def create_cursor(self, name=None):
return FormatStylePlaceholderCursor(self.connection)
def _commit(self):
if self.connection is not None:
with wrap_oracle_errors():
return self.connection.commit()
# Oracle doesn't support releasing savepoints. But we fake them when query
# logging is enabled to keep query counts consistent with other backends.
def _savepoint_commit(self, sid):
if self.queries_logged:
self.queries_log.append({
'sql': '-- RELEASE SAVEPOINT %s (faked)' % self.ops.quote_name(sid),
'time': '0.000',
})
def _set_autocommit(self, autocommit):
with self.wrap_database_errors:
self.connection.autocommit = autocommit
def check_constraints(self, table_names=None):
"""
Check constraints by setting them to immediate. Return them to deferred
afterward.
"""
with self.cursor() as cursor:
cursor.execute('SET CONSTRAINTS ALL IMMEDIATE')
cursor.execute('SET CONSTRAINTS ALL DEFERRED')
def is_usable(self):
try:
self.connection.ping()
except Database.Error:
return False
else:
return True
@cached_property
def oracle_version(self):
with self.temporary_connection():
return tuple(int(x) for x in self.connection.version.split('.'))
class OracleParam:
"""
Wrapper object for formatting parameters for Oracle. If the string
representation of the value is large enough (greater than 4000 characters)
the input size needs to be set as CLOB. Alternatively, if the parameter
has an `input_size` attribute, then the value of the `input_size` attribute
will be used instead. Otherwise, no input size will be set for the
parameter when executing the query.
"""
def __init__(self, param, cursor, strings_only=False):
# With raw SQL queries, datetimes can reach this function
# without being converted by DateTimeField.get_db_prep_value.
if settings.USE_TZ and (isinstance(param, datetime.datetime) and
not isinstance(param, Oracle_datetime)):
param = Oracle_datetime.from_datetime(param)
string_size = 0
# Oracle doesn't recognize True and False correctly.
if param is True:
param = 1
elif param is False:
param = 0
if hasattr(param, 'bind_parameter'):
self.force_bytes = param.bind_parameter(cursor)
elif isinstance(param, (Database.Binary, datetime.timedelta)):
self.force_bytes = param
else:
# To transmit to the database, we need Unicode if supported
# To get size right, we must consider bytes.
self.force_bytes = force_str(param, cursor.charset, strings_only)
if isinstance(self.force_bytes, str):
# We could optimize by only converting up to 4000 bytes here
string_size = len(force_bytes(param, cursor.charset, strings_only))
if hasattr(param, 'input_size'):
# If parameter has `input_size` attribute, use that.
self.input_size = param.input_size
elif string_size > 4000:
# Mark any string param greater than 4000 characters as a CLOB.
self.input_size = Database.CLOB
elif isinstance(param, datetime.datetime):
self.input_size = Database.TIMESTAMP
else:
self.input_size = None
class VariableWrapper:
"""
An adapter class for cursor variables that prevents the wrapped object
from being converted into a string when used to instantiate an OracleParam.
This can be used generally for any other object that should be passed into
Cursor.execute as-is.
"""
def __init__(self, var):
self.var = var
def bind_parameter(self, cursor):
return self.var
def __getattr__(self, key):
return getattr(self.var, key)
def __setattr__(self, key, value):
if key == 'var':
self.__dict__[key] = value
else:
setattr(self.var, key, value)
class FormatStylePlaceholderCursor:
"""
Django uses "format" (e.g. '%s') style placeholders, but Oracle uses ":var"
style. This fixes it -- but note that if you want to use a literal "%s" in
a query, you'll need to use "%%s".
"""
charset = 'utf-8'
def __init__(self, connection):
self.cursor = connection.cursor()
self.cursor.outputtypehandler = self._output_type_handler
@staticmethod
def _output_number_converter(value):
return decimal.Decimal(value) if '.' in value else int(value)
@staticmethod
def _get_decimal_converter(precision, scale):
if scale == 0:
return int
context = decimal.Context(prec=precision)
quantize_value = decimal.Decimal(1).scaleb(-scale)
return lambda v: decimal.Decimal(v).quantize(quantize_value, context=context)
@staticmethod
def _output_type_handler(cursor, name, defaultType, length, precision, scale):
"""
Called for each db column fetched from cursors. Return numbers as the
appropriate Python type.
"""
if defaultType == Database.NUMBER:
if scale == -127:
if precision == 0:
# NUMBER column: decimal-precision floating point.
# This will normally be an integer from a sequence,
# but it could be a decimal value.
outconverter = FormatStylePlaceholderCursor._output_number_converter
else:
# FLOAT column: binary-precision floating point.
# This comes from FloatField columns.
outconverter = float
elif precision > 0:
# NUMBER(p,s) column: decimal-precision fixed point.
# This comes from IntegerField and DecimalField columns.
outconverter = FormatStylePlaceholderCursor._get_decimal_converter(precision, scale)
else:
# No type information. This normally comes from a
# mathematical expression in the SELECT list. Guess int
# or Decimal based on whether it has a decimal point.
outconverter = FormatStylePlaceholderCursor._output_number_converter
return cursor.var(
Database.STRING,
size=255,
arraysize=cursor.arraysize,
outconverter=outconverter,
)
def _format_params(self, params):
try:
return {k: OracleParam(v, self, True) for k, v in params.items()}
except AttributeError:
return tuple(OracleParam(p, self, True) for p in params)
def _guess_input_sizes(self, params_list):
# Try dict handling; if that fails, treat as sequence
if hasattr(params_list[0], 'keys'):
sizes = {}
for params in params_list:
for k, value in params.items():
if value.input_size:
sizes[k] = value.input_size
if sizes:
self.setinputsizes(**sizes)
else:
# It's not a list of dicts; it's a list of sequences
sizes = [None] * len(params_list[0])
for params in params_list:
for i, value in enumerate(params):
if value.input_size:
sizes[i] = value.input_size
if sizes:
self.setinputsizes(*sizes)
def _param_generator(self, params):
# Try dict handling; if that fails, treat as sequence
if hasattr(params, 'items'):
return {k: v.force_bytes for k, v in params.items()}
else:
return [p.force_bytes for p in params]
def _fix_for_params(self, query, params, unify_by_values=False):
# cx_Oracle wants no trailing ';' for SQL statements. For PL/SQL, it
# it does want a trailing ';' but not a trailing '/'. However, these
# characters must be included in the original query in case the query
# is being passed to SQL*Plus.
if query.endswith(';') or query.endswith('/'):
query = query[:-1]
if params is None:
params = []
elif hasattr(params, 'keys'):
# Handle params as dict
args = {k: ":%s" % k for k in params}
query = query % args
elif unify_by_values and params:
# Handle params as a dict with unified query parameters by their
# values. It can be used only in single query execute() because
# executemany() shares the formatted query with each of the params
# list. e.g. for input params = [0.75, 2, 0.75, 'sth', 0.75]
# params_dict = {0.75: ':arg0', 2: ':arg1', 'sth': ':arg2'}
# args = [':arg0', ':arg1', ':arg0', ':arg2', ':arg0']
# params = {':arg0': 0.75, ':arg1': 2, ':arg2': 'sth'}
params_dict = {
param: ':arg%d' % i
for i, param in enumerate(dict.fromkeys(params))
}
args = [params_dict[param] for param in params]
params = {value: key for key, value in params_dict.items()}
query = query % tuple(args)
else:
# Handle params as sequence
args = [(':arg%d' % i) for i in range(len(params))]
query = query % tuple(args)
return query, self._format_params(params)
def execute(self, query, params=None):
query, params = self._fix_for_params(query, params, unify_by_values=True)
self._guess_input_sizes([params])
with wrap_oracle_errors():
return self.cursor.execute(query, self._param_generator(params))
def executemany(self, query, params=None):
if not params:
# No params given, nothing to do
return None
# uniform treatment for sequences and iterables
params_iter = iter(params)
query, firstparams = self._fix_for_params(query, next(params_iter))
# we build a list of formatted params; as we're going to traverse it
# more than once, we can't make it lazy by using a generator
formatted = [firstparams] + [self._format_params(p) for p in params_iter]
self._guess_input_sizes(formatted)
with wrap_oracle_errors():
return self.cursor.executemany(query, [self._param_generator(p) for p in formatted])
def close(self):
try:
self.cursor.close()
except Database.InterfaceError:
# already closed
pass
def var(self, *args):
return VariableWrapper(self.cursor.var(*args))
def arrayvar(self, *args):
return VariableWrapper(self.cursor.arrayvar(*args))
def __getattr__(self, attr):
return getattr(self.cursor, attr)
def __iter__(self):
return iter(self.cursor)
|
86c1a9c84247e83e1975cfc94a4bdffd36cfe71b9dc3f2980d81cc0a3c34376c | import datetime
import uuid
from functools import lru_cache
from django.conf import settings
from django.db import DatabaseError, NotSupportedError
from django.db.backends.base.operations import BaseDatabaseOperations
from django.db.backends.utils import strip_quotes, truncate_name
from django.db.models import AutoField, Exists, ExpressionWrapper
from django.db.models.expressions import RawSQL
from django.db.models.sql.where import WhereNode
from django.utils import timezone
from django.utils.encoding import force_bytes, force_str
from django.utils.functional import cached_property
from django.utils.regex_helper import _lazy_re_compile
from .base import Database
from .utils import BulkInsertMapper, InsertVar, Oracle_datetime
class DatabaseOperations(BaseDatabaseOperations):
# Oracle uses NUMBER(5), NUMBER(11), and NUMBER(19) for integer fields.
# SmallIntegerField uses NUMBER(11) instead of NUMBER(5), which is used by
# SmallAutoField, to preserve backward compatibility.
integer_field_ranges = {
'SmallIntegerField': (-99999999999, 99999999999),
'IntegerField': (-99999999999, 99999999999),
'BigIntegerField': (-9999999999999999999, 9999999999999999999),
'PositiveBigIntegerField': (0, 9999999999999999999),
'PositiveSmallIntegerField': (0, 99999999999),
'PositiveIntegerField': (0, 99999999999),
'SmallAutoField': (-99999, 99999),
'AutoField': (-99999999999, 99999999999),
'BigAutoField': (-9999999999999999999, 9999999999999999999),
}
set_operators = {**BaseDatabaseOperations.set_operators, 'difference': 'MINUS'}
# TODO: colorize this SQL code with style.SQL_KEYWORD(), etc.
_sequence_reset_sql = """
DECLARE
table_value integer;
seq_value integer;
seq_name user_tab_identity_cols.sequence_name%%TYPE;
BEGIN
BEGIN
SELECT sequence_name INTO seq_name FROM user_tab_identity_cols
WHERE table_name = '%(table_name)s' AND
column_name = '%(column_name)s';
EXCEPTION WHEN NO_DATA_FOUND THEN
seq_name := '%(no_autofield_sequence_name)s';
END;
SELECT NVL(MAX(%(column)s), 0) INTO table_value FROM %(table)s;
SELECT NVL(last_number - cache_size, 0) INTO seq_value FROM user_sequences
WHERE sequence_name = seq_name;
WHILE table_value > seq_value LOOP
EXECUTE IMMEDIATE 'SELECT "'||seq_name||'".nextval FROM DUAL'
INTO seq_value;
END LOOP;
END;
/"""
# Oracle doesn't support string without precision; use the max string size.
cast_char_field_without_max_length = 'NVARCHAR2(2000)'
cast_data_types = {
'AutoField': 'NUMBER(11)',
'BigAutoField': 'NUMBER(19)',
'SmallAutoField': 'NUMBER(5)',
'TextField': cast_char_field_without_max_length,
}
def cache_key_culling_sql(self):
return 'SELECT cache_key FROM %s ORDER BY cache_key OFFSET %%s ROWS FETCH FIRST 1 ROWS ONLY'
def date_extract_sql(self, lookup_type, field_name):
if lookup_type == 'week_day':
# TO_CHAR(field, 'D') returns an integer from 1-7, where 1=Sunday.
return "TO_CHAR(%s, 'D')" % field_name
elif lookup_type == 'iso_week_day':
return "TO_CHAR(%s - 1, 'D')" % field_name
elif lookup_type == 'week':
# IW = ISO week number
return "TO_CHAR(%s, 'IW')" % field_name
elif lookup_type == 'quarter':
return "TO_CHAR(%s, 'Q')" % field_name
elif lookup_type == 'iso_year':
return "TO_CHAR(%s, 'IYYY')" % field_name
else:
# https://docs.oracle.com/en/database/oracle/oracle-database/18/sqlrf/EXTRACT-datetime.html
return "EXTRACT(%s FROM %s)" % (lookup_type.upper(), field_name)
def date_trunc_sql(self, lookup_type, field_name):
# https://docs.oracle.com/en/database/oracle/oracle-database/18/sqlrf/ROUND-and-TRUNC-Date-Functions.html
if lookup_type in ('year', 'month'):
return "TRUNC(%s, '%s')" % (field_name, lookup_type.upper())
elif lookup_type == 'quarter':
return "TRUNC(%s, 'Q')" % field_name
elif lookup_type == 'week':
return "TRUNC(%s, 'IW')" % field_name
else:
return "TRUNC(%s)" % field_name
# Oracle crashes with "ORA-03113: end-of-file on communication channel"
# if the time zone name is passed in parameter. Use interpolation instead.
# https://groups.google.com/forum/#!msg/django-developers/zwQju7hbG78/9l934yelwfsJ
# This regexp matches all time zone names from the zoneinfo database.
_tzname_re = _lazy_re_compile(r'^[\w/:+-]+$')
def _prepare_tzname_delta(self, tzname):
if '+' in tzname:
return tzname[tzname.find('+'):]
elif '-' in tzname:
return tzname[tzname.find('-'):]
return tzname
def _convert_field_to_tz(self, field_name, tzname):
if not settings.USE_TZ:
return field_name
if not self._tzname_re.match(tzname):
raise ValueError("Invalid time zone name: %s" % tzname)
# Convert from connection timezone to the local time, returning
# TIMESTAMP WITH TIME ZONE and cast it back to TIMESTAMP to strip the
# TIME ZONE details.
if self.connection.timezone_name != tzname:
return "CAST((FROM_TZ(%s, '%s') AT TIME ZONE '%s') AS TIMESTAMP)" % (
field_name,
self.connection.timezone_name,
self._prepare_tzname_delta(tzname),
)
return field_name
def datetime_cast_date_sql(self, field_name, tzname):
field_name = self._convert_field_to_tz(field_name, tzname)
return 'TRUNC(%s)' % field_name
def datetime_cast_time_sql(self, field_name, tzname):
# Since `TimeField` values are stored as TIMESTAMP where only the date
# part is ignored, convert the field to the specified timezone.
return self._convert_field_to_tz(field_name, tzname)
def datetime_extract_sql(self, lookup_type, field_name, tzname):
field_name = self._convert_field_to_tz(field_name, tzname)
return self.date_extract_sql(lookup_type, field_name)
def datetime_trunc_sql(self, lookup_type, field_name, tzname):
field_name = self._convert_field_to_tz(field_name, tzname)
# https://docs.oracle.com/en/database/oracle/oracle-database/18/sqlrf/ROUND-and-TRUNC-Date-Functions.html
if lookup_type in ('year', 'month'):
sql = "TRUNC(%s, '%s')" % (field_name, lookup_type.upper())
elif lookup_type == 'quarter':
sql = "TRUNC(%s, 'Q')" % field_name
elif lookup_type == 'week':
sql = "TRUNC(%s, 'IW')" % field_name
elif lookup_type == 'day':
sql = "TRUNC(%s)" % field_name
elif lookup_type == 'hour':
sql = "TRUNC(%s, 'HH24')" % field_name
elif lookup_type == 'minute':
sql = "TRUNC(%s, 'MI')" % field_name
else:
sql = "CAST(%s AS DATE)" % field_name # Cast to DATE removes sub-second precision.
return sql
def time_trunc_sql(self, lookup_type, field_name):
# The implementation is similar to `datetime_trunc_sql` as both
# `DateTimeField` and `TimeField` are stored as TIMESTAMP where
# the date part of the later is ignored.
if lookup_type == 'hour':
sql = "TRUNC(%s, 'HH24')" % field_name
elif lookup_type == 'minute':
sql = "TRUNC(%s, 'MI')" % field_name
elif lookup_type == 'second':
sql = "CAST(%s AS DATE)" % field_name # Cast to DATE removes sub-second precision.
return sql
def get_db_converters(self, expression):
converters = super().get_db_converters(expression)
internal_type = expression.output_field.get_internal_type()
if internal_type in ['JSONField', 'TextField']:
converters.append(self.convert_textfield_value)
elif internal_type == 'BinaryField':
converters.append(self.convert_binaryfield_value)
elif internal_type in ['BooleanField', 'NullBooleanField']:
converters.append(self.convert_booleanfield_value)
elif internal_type == 'DateTimeField':
if settings.USE_TZ:
converters.append(self.convert_datetimefield_value)
elif internal_type == 'DateField':
converters.append(self.convert_datefield_value)
elif internal_type == 'TimeField':
converters.append(self.convert_timefield_value)
elif internal_type == 'UUIDField':
converters.append(self.convert_uuidfield_value)
# Oracle stores empty strings as null. If the field accepts the empty
# string, undo this to adhere to the Django convention of using
# the empty string instead of null.
if expression.field.empty_strings_allowed:
converters.append(
self.convert_empty_bytes
if internal_type == 'BinaryField' else
self.convert_empty_string
)
return converters
def convert_textfield_value(self, value, expression, connection):
if isinstance(value, Database.LOB):
value = value.read()
return value
def convert_binaryfield_value(self, value, expression, connection):
if isinstance(value, Database.LOB):
value = force_bytes(value.read())
return value
def convert_booleanfield_value(self, value, expression, connection):
if value in (0, 1):
value = bool(value)
return value
# cx_Oracle always returns datetime.datetime objects for
# DATE and TIMESTAMP columns, but Django wants to see a
# python datetime.date, .time, or .datetime.
def convert_datetimefield_value(self, value, expression, connection):
if value is not None:
value = timezone.make_aware(value, self.connection.timezone)
return value
def convert_datefield_value(self, value, expression, connection):
if isinstance(value, Database.Timestamp):
value = value.date()
return value
def convert_timefield_value(self, value, expression, connection):
if isinstance(value, Database.Timestamp):
value = value.time()
return value
def convert_uuidfield_value(self, value, expression, connection):
if value is not None:
value = uuid.UUID(value)
return value
@staticmethod
def convert_empty_string(value, expression, connection):
return '' if value is None else value
@staticmethod
def convert_empty_bytes(value, expression, connection):
return b'' if value is None else value
def deferrable_sql(self):
return " DEFERRABLE INITIALLY DEFERRED"
def fetch_returned_insert_columns(self, cursor, returning_params):
columns = []
for param in returning_params:
value = param.get_value()
if value is None or value == []:
# cx_Oracle < 6.3 returns None, >= 6.3 returns empty list.
raise DatabaseError(
'The database did not return a new row id. Probably '
'"ORA-1403: no data found" was raised internally but was '
'hidden by the Oracle OCI library (see '
'https://code.djangoproject.com/ticket/28859).'
)
# cx_Oracle < 7 returns value, >= 7 returns list with single value.
columns.append(value[0] if isinstance(value, list) else value)
return tuple(columns)
def field_cast_sql(self, db_type, internal_type):
if db_type and db_type.endswith('LOB') and internal_type != 'JSONField':
return "DBMS_LOB.SUBSTR(%s)"
else:
return "%s"
def no_limit_value(self):
return None
def limit_offset_sql(self, low_mark, high_mark):
fetch, offset = self._get_limit_offset_params(low_mark, high_mark)
return ' '.join(sql for sql in (
('OFFSET %d ROWS' % offset) if offset else None,
('FETCH FIRST %d ROWS ONLY' % fetch) if fetch else None,
) if sql)
def last_executed_query(self, cursor, sql, params):
# https://cx-oracle.readthedocs.io/en/latest/cursor.html#Cursor.statement
# The DB API definition does not define this attribute.
statement = cursor.statement
# Unlike Psycopg's `query` and MySQLdb`'s `_executed`, cx_Oracle's
# `statement` doesn't contain the query parameters. Substitute
# parameters manually.
if isinstance(params, (tuple, list)):
for i, param in enumerate(params):
statement = statement.replace(':arg%d' % i, force_str(param, errors='replace'))
elif isinstance(params, dict):
for key, param in params.items():
statement = statement.replace(':%s' % key, force_str(param, errors='replace'))
return statement
def last_insert_id(self, cursor, table_name, pk_name):
sq_name = self._get_sequence_name(cursor, strip_quotes(table_name), pk_name)
cursor.execute('"%s".currval' % sq_name)
return cursor.fetchone()[0]
def lookup_cast(self, lookup_type, internal_type=None):
if lookup_type in ('iexact', 'icontains', 'istartswith', 'iendswith'):
return "UPPER(%s)"
if internal_type == 'JSONField' and lookup_type == 'exact':
return 'DBMS_LOB.SUBSTR(%s)'
return "%s"
def max_in_list_size(self):
return 1000
def max_name_length(self):
return 30
def pk_default_value(self):
return "NULL"
def prep_for_iexact_query(self, x):
return x
def process_clob(self, value):
if value is None:
return ''
return value.read()
def quote_name(self, name):
# SQL92 requires delimited (quoted) names to be case-sensitive. When
# not quoted, Oracle has case-insensitive behavior for identifiers, but
# always defaults to uppercase.
# We simplify things by making Oracle identifiers always uppercase.
if not name.startswith('"') and not name.endswith('"'):
name = '"%s"' % truncate_name(name.upper(), self.max_name_length())
# Oracle puts the query text into a (query % args) construct, so % signs
# in names need to be escaped. The '%%' will be collapsed back to '%' at
# that stage so we aren't really making the name longer here.
name = name.replace('%', '%%')
return name.upper()
def random_function_sql(self):
return "DBMS_RANDOM.RANDOM"
def regex_lookup(self, lookup_type):
if lookup_type == 'regex':
match_option = "'c'"
else:
match_option = "'i'"
return 'REGEXP_LIKE(%%s, %%s, %s)' % match_option
def return_insert_columns(self, fields):
if not fields:
return '', ()
field_names = []
params = []
for field in fields:
field_names.append('%s.%s' % (
self.quote_name(field.model._meta.db_table),
self.quote_name(field.column),
))
params.append(InsertVar(field))
return 'RETURNING %s INTO %s' % (
', '.join(field_names),
', '.join(['%s'] * len(params)),
), tuple(params)
def __foreign_key_constraints(self, table_name, recursive):
with self.connection.cursor() as cursor:
if recursive:
cursor.execute("""
SELECT
user_tables.table_name, rcons.constraint_name
FROM
user_tables
JOIN
user_constraints cons
ON (user_tables.table_name = cons.table_name AND cons.constraint_type = ANY('P', 'U'))
LEFT JOIN
user_constraints rcons
ON (user_tables.table_name = rcons.table_name AND rcons.constraint_type = 'R')
START WITH user_tables.table_name = UPPER(%s)
CONNECT BY NOCYCLE PRIOR cons.constraint_name = rcons.r_constraint_name
GROUP BY
user_tables.table_name, rcons.constraint_name
HAVING user_tables.table_name != UPPER(%s)
ORDER BY MAX(level) DESC
""", (table_name, table_name))
else:
cursor.execute("""
SELECT
cons.table_name, cons.constraint_name
FROM
user_constraints cons
WHERE
cons.constraint_type = 'R'
AND cons.table_name = UPPER(%s)
""", (table_name,))
return cursor.fetchall()
@cached_property
def _foreign_key_constraints(self):
# 512 is large enough to fit the ~330 tables (as of this writing) in
# Django's test suite.
return lru_cache(maxsize=512)(self.__foreign_key_constraints)
def sql_flush(self, style, tables, *, reset_sequences=False, allow_cascade=False):
if not tables:
return []
truncated_tables = {table.upper() for table in tables}
constraints = set()
# Oracle's TRUNCATE CASCADE only works with ON DELETE CASCADE foreign
# keys which Django doesn't define. Emulate the PostgreSQL behavior
# which truncates all dependent tables by manually retrieving all
# foreign key constraints and resolving dependencies.
for table in tables:
for foreign_table, constraint in self._foreign_key_constraints(table, recursive=allow_cascade):
if allow_cascade:
truncated_tables.add(foreign_table)
constraints.add((foreign_table, constraint))
sql = [
'%s %s %s %s %s %s %s %s;' % (
style.SQL_KEYWORD('ALTER'),
style.SQL_KEYWORD('TABLE'),
style.SQL_FIELD(self.quote_name(table)),
style.SQL_KEYWORD('DISABLE'),
style.SQL_KEYWORD('CONSTRAINT'),
style.SQL_FIELD(self.quote_name(constraint)),
style.SQL_KEYWORD('KEEP'),
style.SQL_KEYWORD('INDEX'),
) for table, constraint in constraints
] + [
'%s %s %s;' % (
style.SQL_KEYWORD('TRUNCATE'),
style.SQL_KEYWORD('TABLE'),
style.SQL_FIELD(self.quote_name(table)),
) for table in truncated_tables
] + [
'%s %s %s %s %s %s;' % (
style.SQL_KEYWORD('ALTER'),
style.SQL_KEYWORD('TABLE'),
style.SQL_FIELD(self.quote_name(table)),
style.SQL_KEYWORD('ENABLE'),
style.SQL_KEYWORD('CONSTRAINT'),
style.SQL_FIELD(self.quote_name(constraint)),
) for table, constraint in constraints
]
if reset_sequences:
sequences = [
sequence
for sequence in self.connection.introspection.sequence_list()
if sequence['table'].upper() in truncated_tables
]
# Since we've just deleted all the rows, running our sequence ALTER
# code will reset the sequence to 0.
sql.extend(self.sequence_reset_by_name_sql(style, sequences))
return sql
def sequence_reset_by_name_sql(self, style, sequences):
sql = []
for sequence_info in sequences:
no_autofield_sequence_name = self._get_no_autofield_sequence_name(sequence_info['table'])
table = self.quote_name(sequence_info['table'])
column = self.quote_name(sequence_info['column'] or 'id')
query = self._sequence_reset_sql % {
'no_autofield_sequence_name': no_autofield_sequence_name,
'table': table,
'column': column,
'table_name': strip_quotes(table),
'column_name': strip_quotes(column),
}
sql.append(query)
return sql
def sequence_reset_sql(self, style, model_list):
output = []
query = self._sequence_reset_sql
for model in model_list:
for f in model._meta.local_fields:
if isinstance(f, AutoField):
no_autofield_sequence_name = self._get_no_autofield_sequence_name(model._meta.db_table)
table = self.quote_name(model._meta.db_table)
column = self.quote_name(f.column)
output.append(query % {
'no_autofield_sequence_name': no_autofield_sequence_name,
'table': table,
'column': column,
'table_name': strip_quotes(table),
'column_name': strip_quotes(column),
})
# Only one AutoField is allowed per model, so don't
# continue to loop
break
for f in model._meta.many_to_many:
if not f.remote_field.through:
no_autofield_sequence_name = self._get_no_autofield_sequence_name(f.m2m_db_table())
table = self.quote_name(f.m2m_db_table())
column = self.quote_name('id')
output.append(query % {
'no_autofield_sequence_name': no_autofield_sequence_name,
'table': table,
'column': column,
'table_name': strip_quotes(table),
'column_name': 'ID',
})
return output
def start_transaction_sql(self):
return ''
def tablespace_sql(self, tablespace, inline=False):
if inline:
return "USING INDEX TABLESPACE %s" % self.quote_name(tablespace)
else:
return "TABLESPACE %s" % self.quote_name(tablespace)
def adapt_datefield_value(self, value):
"""
Transform a date value to an object compatible with what is expected
by the backend driver for date columns.
The default implementation transforms the date to text, but that is not
necessary for Oracle.
"""
return value
def adapt_datetimefield_value(self, value):
"""
Transform a datetime value to an object compatible with what is expected
by the backend driver for datetime columns.
If naive datetime is passed assumes that is in UTC. Normally Django
models.DateTimeField makes sure that if USE_TZ is True passed datetime
is timezone aware.
"""
if value is None:
return None
# Expression values are adapted by the database.
if hasattr(value, 'resolve_expression'):
return value
# cx_Oracle doesn't support tz-aware datetimes
if timezone.is_aware(value):
if settings.USE_TZ:
value = timezone.make_naive(value, self.connection.timezone)
else:
raise ValueError("Oracle backend does not support timezone-aware datetimes when USE_TZ is False.")
return Oracle_datetime.from_datetime(value)
def adapt_timefield_value(self, value):
if value is None:
return None
# Expression values are adapted by the database.
if hasattr(value, 'resolve_expression'):
return value
if isinstance(value, str):
return datetime.datetime.strptime(value, '%H:%M:%S')
# Oracle doesn't support tz-aware times
if timezone.is_aware(value):
raise ValueError("Oracle backend does not support timezone-aware times.")
return Oracle_datetime(1900, 1, 1, value.hour, value.minute,
value.second, value.microsecond)
def combine_expression(self, connector, sub_expressions):
lhs, rhs = sub_expressions
if connector == '%%':
return 'MOD(%s)' % ','.join(sub_expressions)
elif connector == '&':
return 'BITAND(%s)' % ','.join(sub_expressions)
elif connector == '|':
return 'BITAND(-%(lhs)s-1,%(rhs)s)+%(lhs)s' % {'lhs': lhs, 'rhs': rhs}
elif connector == '<<':
return '(%(lhs)s * POWER(2, %(rhs)s))' % {'lhs': lhs, 'rhs': rhs}
elif connector == '>>':
return 'FLOOR(%(lhs)s / POWER(2, %(rhs)s))' % {'lhs': lhs, 'rhs': rhs}
elif connector == '^':
return 'POWER(%s)' % ','.join(sub_expressions)
elif connector == '#':
raise NotSupportedError('Bitwise XOR is not supported in Oracle.')
return super().combine_expression(connector, sub_expressions)
def _get_no_autofield_sequence_name(self, table):
"""
Manually created sequence name to keep backward compatibility for
AutoFields that aren't Oracle identity columns.
"""
name_length = self.max_name_length() - 3
return '%s_SQ' % truncate_name(strip_quotes(table), name_length).upper()
def _get_sequence_name(self, cursor, table, pk_name):
cursor.execute("""
SELECT sequence_name
FROM user_tab_identity_cols
WHERE table_name = UPPER(%s)
AND column_name = UPPER(%s)""", [table, pk_name])
row = cursor.fetchone()
return self._get_no_autofield_sequence_name(table) if row is None else row[0]
def bulk_insert_sql(self, fields, placeholder_rows):
query = []
for row in placeholder_rows:
select = []
for i, placeholder in enumerate(row):
# A model without any fields has fields=[None].
if fields[i]:
internal_type = getattr(fields[i], 'target_field', fields[i]).get_internal_type()
placeholder = BulkInsertMapper.types.get(internal_type, '%s') % placeholder
# Add columns aliases to the first select to avoid "ORA-00918:
# column ambiguously defined" when two or more columns in the
# first select have the same value.
if not query:
placeholder = '%s col_%s' % (placeholder, i)
select.append(placeholder)
query.append('SELECT %s FROM DUAL' % ', '.join(select))
# Bulk insert to tables with Oracle identity columns causes Oracle to
# add sequence.nextval to it. Sequence.nextval cannot be used with the
# UNION operator. To prevent incorrect SQL, move UNION to a subquery.
return 'SELECT * FROM (%s)' % ' UNION ALL '.join(query)
def subtract_temporals(self, internal_type, lhs, rhs):
if internal_type == 'DateField':
lhs_sql, lhs_params = lhs
rhs_sql, rhs_params = rhs
params = (*lhs_params, *rhs_params)
return "NUMTODSINTERVAL(TO_NUMBER(%s - %s), 'DAY')" % (lhs_sql, rhs_sql), params
return super().subtract_temporals(internal_type, lhs, rhs)
def bulk_batch_size(self, fields, objs):
"""Oracle restricts the number of parameters in a query."""
if fields:
return self.connection.features.max_query_params // len(fields)
return len(objs)
def conditional_expression_supported_in_where_clause(self, expression):
"""
Oracle supports only EXISTS(...) or filters in the WHERE clause, others
must be compared with True.
"""
if isinstance(expression, (Exists, WhereNode)):
return True
if isinstance(expression, ExpressionWrapper) and expression.conditional:
return self.conditional_expression_supported_in_where_clause(expression.expression)
if isinstance(expression, RawSQL) and expression.conditional:
return True
return False
|
2d4fa579f797f7b4143c226fcc9f36aed17fd55804494a511e3a9be3bc671f44 | import copy
import datetime
import re
from django.db import DatabaseError
from django.db.backends.base.schema import BaseDatabaseSchemaEditor
class DatabaseSchemaEditor(BaseDatabaseSchemaEditor):
sql_create_column = "ALTER TABLE %(table)s ADD %(column)s %(definition)s"
sql_alter_column_type = "MODIFY %(column)s %(type)s"
sql_alter_column_null = "MODIFY %(column)s NULL"
sql_alter_column_not_null = "MODIFY %(column)s NOT NULL"
sql_alter_column_default = "MODIFY %(column)s DEFAULT %(default)s"
sql_alter_column_no_default = "MODIFY %(column)s DEFAULT NULL"
sql_delete_column = "ALTER TABLE %(table)s DROP COLUMN %(column)s"
sql_create_column_inline_fk = 'CONSTRAINT %(name)s REFERENCES %(to_table)s(%(to_column)s)%(deferrable)s'
sql_delete_table = "DROP TABLE %(table)s CASCADE CONSTRAINTS"
sql_create_index = "CREATE INDEX %(name)s ON %(table)s (%(columns)s)%(extra)s"
def quote_value(self, value):
if isinstance(value, (datetime.date, datetime.time, datetime.datetime)):
return "'%s'" % value
elif isinstance(value, str):
return "'%s'" % value.replace("\'", "\'\'").replace('%', '%%')
elif isinstance(value, (bytes, bytearray, memoryview)):
return "'%s'" % value.hex()
elif isinstance(value, bool):
return "1" if value else "0"
else:
return str(value)
def remove_field(self, model, field):
# If the column is an identity column, drop the identity before
# removing the field.
if self._is_identity_column(model._meta.db_table, field.column):
self._drop_identity(model._meta.db_table, field.column)
super().remove_field(model, field)
def delete_model(self, model):
# Run superclass action
super().delete_model(model)
# Clean up manually created sequence.
self.execute("""
DECLARE
i INTEGER;
BEGIN
SELECT COUNT(1) INTO i FROM USER_SEQUENCES
WHERE SEQUENCE_NAME = '%(sq_name)s';
IF i = 1 THEN
EXECUTE IMMEDIATE 'DROP SEQUENCE "%(sq_name)s"';
END IF;
END;
/""" % {'sq_name': self.connection.ops._get_no_autofield_sequence_name(model._meta.db_table)})
def alter_field(self, model, old_field, new_field, strict=False):
try:
super().alter_field(model, old_field, new_field, strict)
except DatabaseError as e:
description = str(e)
# If we're changing type to an unsupported type we need a
# SQLite-ish workaround
if 'ORA-22858' in description or 'ORA-22859' in description:
self._alter_field_type_workaround(model, old_field, new_field)
# If an identity column is changing to a non-numeric type, drop the
# identity first.
elif 'ORA-30675' in description:
self._drop_identity(model._meta.db_table, old_field.column)
self.alter_field(model, old_field, new_field, strict)
# If a primary key column is changing to an identity column, drop
# the primary key first.
elif 'ORA-30673' in description and old_field.primary_key:
self._delete_primary_key(model, strict=True)
self._alter_field_type_workaround(model, old_field, new_field)
else:
raise
def _alter_field_type_workaround(self, model, old_field, new_field):
"""
Oracle refuses to change from some type to other type.
What we need to do instead is:
- Add a nullable version of the desired field with a temporary name. If
the new column is an auto field, then the temporary column can't be
nullable.
- Update the table to transfer values from old to new
- Drop old column
- Rename the new column and possibly drop the nullable property
"""
# Make a new field that's like the new one but with a temporary
# column name.
new_temp_field = copy.deepcopy(new_field)
new_temp_field.null = (new_field.get_internal_type() not in ('AutoField', 'BigAutoField', 'SmallAutoField'))
new_temp_field.column = self._generate_temp_name(new_field.column)
# Add it
self.add_field(model, new_temp_field)
# Explicit data type conversion
# https://docs.oracle.com/en/database/oracle/oracle-database/18/sqlrf
# /Data-Type-Comparison-Rules.html#GUID-D0C5A47E-6F93-4C2D-9E49-4F2B86B359DD
new_value = self.quote_name(old_field.column)
old_type = old_field.db_type(self.connection)
if re.match('^N?CLOB', old_type):
new_value = "TO_CHAR(%s)" % new_value
old_type = 'VARCHAR2'
if re.match('^N?VARCHAR2', old_type):
new_internal_type = new_field.get_internal_type()
if new_internal_type == 'DateField':
new_value = "TO_DATE(%s, 'YYYY-MM-DD')" % new_value
elif new_internal_type == 'DateTimeField':
new_value = "TO_TIMESTAMP(%s, 'YYYY-MM-DD HH24:MI:SS.FF')" % new_value
elif new_internal_type == 'TimeField':
# TimeField are stored as TIMESTAMP with a 1900-01-01 date part.
new_value = "TO_TIMESTAMP(CONCAT('1900-01-01 ', %s), 'YYYY-MM-DD HH24:MI:SS.FF')" % new_value
# Transfer values across
self.execute("UPDATE %s set %s=%s" % (
self.quote_name(model._meta.db_table),
self.quote_name(new_temp_field.column),
new_value,
))
# Drop the old field
self.remove_field(model, old_field)
# Rename and possibly make the new field NOT NULL
super().alter_field(model, new_temp_field, new_field)
def normalize_name(self, name):
"""
Get the properly shortened and uppercased identifier as returned by
quote_name() but without the quotes.
"""
nn = self.quote_name(name)
if nn[0] == '"' and nn[-1] == '"':
nn = nn[1:-1]
return nn
def _generate_temp_name(self, for_name):
"""Generate temporary names for workarounds that need temp columns."""
suffix = hex(hash(for_name)).upper()[1:]
return self.normalize_name(for_name + "_" + suffix)
def prepare_default(self, value):
return self.quote_value(value)
def _field_should_be_indexed(self, model, field):
create_index = super()._field_should_be_indexed(model, field)
db_type = field.db_type(self.connection)
if db_type is not None and db_type.lower() in self.connection._limited_data_types:
return False
return create_index
def _unique_should_be_added(self, old_field, new_field):
return (
super()._unique_should_be_added(old_field, new_field) and
not self._field_became_primary_key(old_field, new_field)
)
def _is_identity_column(self, table_name, column_name):
with self.connection.cursor() as cursor:
cursor.execute("""
SELECT
CASE WHEN identity_column = 'YES' THEN 1 ELSE 0 END
FROM user_tab_cols
WHERE table_name = %s AND
column_name = %s
""", [self.normalize_name(table_name), self.normalize_name(column_name)])
row = cursor.fetchone()
return row[0] if row else False
def _drop_identity(self, table_name, column_name):
self.execute('ALTER TABLE %(table)s MODIFY %(column)s DROP IDENTITY' % {
'table': self.quote_name(table_name),
'column': self.quote_name(column_name),
})
|
564e004e00cb738c50cdbd3a3053be370e8e03cd6c4a9a932461d111dbcd16f9 | import shutil
import subprocess
from django.db.backends.base.client import BaseDatabaseClient
class DatabaseClient(BaseDatabaseClient):
executable_name = 'sqlplus'
wrapper_name = 'rlwrap'
def runshell(self, parameters):
conn_string = self.connection._connect_string()
args = [self.executable_name, "-L", conn_string]
wrapper_path = shutil.which(self.wrapper_name)
if wrapper_path:
args = [wrapper_path, *args]
args.extend(parameters)
subprocess.run(args, check=True)
|
e176a7ec60f0a3a607e8498aafbcc8dd7ae2bff34d7fa6f0f5cc49650334569b | import datetime
from .base import Database
class InsertVar:
"""
A late-binding cursor variable that can be passed to Cursor.execute
as a parameter, in order to receive the id of the row created by an
insert statement.
"""
types = {
'AutoField': int,
'BigAutoField': int,
'SmallAutoField': int,
'IntegerField': int,
'BigIntegerField': int,
'SmallIntegerField': int,
'PositiveBigIntegerField': int,
'PositiveSmallIntegerField': int,
'PositiveIntegerField': int,
'FloatField': Database.NATIVE_FLOAT,
'DateTimeField': Database.TIMESTAMP,
'DateField': Database.Date,
'DecimalField': Database.NUMBER,
}
def __init__(self, field):
internal_type = getattr(field, 'target_field', field).get_internal_type()
self.db_type = self.types.get(internal_type, str)
self.bound_param = None
def bind_parameter(self, cursor):
self.bound_param = cursor.cursor.var(self.db_type)
return self.bound_param
def get_value(self):
return self.bound_param.getvalue()
class Oracle_datetime(datetime.datetime):
"""
A datetime object, with an additional class attribute
to tell cx_Oracle to save the microseconds too.
"""
input_size = Database.TIMESTAMP
@classmethod
def from_datetime(cls, dt):
return Oracle_datetime(
dt.year, dt.month, dt.day,
dt.hour, dt.minute, dt.second, dt.microsecond,
)
class BulkInsertMapper:
BLOB = 'TO_BLOB(%s)'
CLOB = 'TO_CLOB(%s)'
DATE = 'TO_DATE(%s)'
INTERVAL = 'CAST(%s as INTERVAL DAY(9) TO SECOND(6))'
NUMBER = 'TO_NUMBER(%s)'
TIMESTAMP = 'TO_TIMESTAMP(%s)'
types = {
'AutoField': NUMBER,
'BigAutoField': NUMBER,
'BigIntegerField': NUMBER,
'BinaryField': BLOB,
'BooleanField': NUMBER,
'DateField': DATE,
'DateTimeField': TIMESTAMP,
'DecimalField': NUMBER,
'DurationField': INTERVAL,
'FloatField': NUMBER,
'IntegerField': NUMBER,
'NullBooleanField': NUMBER,
'PositiveBigIntegerField': NUMBER,
'PositiveIntegerField': NUMBER,
'PositiveSmallIntegerField': NUMBER,
'SmallAutoField': NUMBER,
'SmallIntegerField': NUMBER,
'TextField': CLOB,
'TimeField': TIMESTAMP,
}
|
3c82b668a48bec84d63d5f8778fbb48e9d2169bdf86fd8985d92a14277442688 | import sys
from django.conf import settings
from django.db import DatabaseError
from django.db.backends.base.creation import BaseDatabaseCreation
from django.utils.crypto import get_random_string
from django.utils.functional import cached_property
TEST_DATABASE_PREFIX = 'test_'
class DatabaseCreation(BaseDatabaseCreation):
@cached_property
def _maindb_connection(self):
"""
This is analogous to other backends' `_nodb_connection` property,
which allows access to an "administrative" connection which can
be used to manage the test databases.
For Oracle, the only connection that can be used for that purpose
is the main (non-test) connection.
"""
settings_dict = settings.DATABASES[self.connection.alias]
user = settings_dict.get('SAVED_USER') or settings_dict['USER']
password = settings_dict.get('SAVED_PASSWORD') or settings_dict['PASSWORD']
settings_dict = {**settings_dict, 'USER': user, 'PASSWORD': password}
DatabaseWrapper = type(self.connection)
return DatabaseWrapper(settings_dict, alias=self.connection.alias)
def _create_test_db(self, verbosity=1, autoclobber=False, keepdb=False):
parameters = self._get_test_db_params()
with self._maindb_connection.cursor() as cursor:
if self._test_database_create():
try:
self._execute_test_db_creation(cursor, parameters, verbosity, keepdb)
except Exception as e:
if 'ORA-01543' not in str(e):
# All errors except "tablespace already exists" cancel tests
self.log('Got an error creating the test database: %s' % e)
sys.exit(2)
if not autoclobber:
confirm = input(
"It appears the test database, %s, already exists. "
"Type 'yes' to delete it, or 'no' to cancel: " % parameters['user'])
if autoclobber or confirm == 'yes':
if verbosity >= 1:
self.log("Destroying old test database for alias '%s'..." % self.connection.alias)
try:
self._execute_test_db_destruction(cursor, parameters, verbosity)
except DatabaseError as e:
if 'ORA-29857' in str(e):
self._handle_objects_preventing_db_destruction(cursor, parameters,
verbosity, autoclobber)
else:
# Ran into a database error that isn't about leftover objects in the tablespace
self.log('Got an error destroying the old test database: %s' % e)
sys.exit(2)
except Exception as e:
self.log('Got an error destroying the old test database: %s' % e)
sys.exit(2)
try:
self._execute_test_db_creation(cursor, parameters, verbosity, keepdb)
except Exception as e:
self.log('Got an error recreating the test database: %s' % e)
sys.exit(2)
else:
self.log('Tests cancelled.')
sys.exit(1)
if self._test_user_create():
if verbosity >= 1:
self.log('Creating test user...')
try:
self._create_test_user(cursor, parameters, verbosity, keepdb)
except Exception as e:
if 'ORA-01920' not in str(e):
# All errors except "user already exists" cancel tests
self.log('Got an error creating the test user: %s' % e)
sys.exit(2)
if not autoclobber:
confirm = input(
"It appears the test user, %s, already exists. Type "
"'yes' to delete it, or 'no' to cancel: " % parameters['user'])
if autoclobber or confirm == 'yes':
try:
if verbosity >= 1:
self.log('Destroying old test user...')
self._destroy_test_user(cursor, parameters, verbosity)
if verbosity >= 1:
self.log('Creating test user...')
self._create_test_user(cursor, parameters, verbosity, keepdb)
except Exception as e:
self.log('Got an error recreating the test user: %s' % e)
sys.exit(2)
else:
self.log('Tests cancelled.')
sys.exit(1)
self._maindb_connection.close() # done with main user -- test user and tablespaces created
self._switch_to_test_user(parameters)
return self.connection.settings_dict['NAME']
def _switch_to_test_user(self, parameters):
"""
Switch to the user that's used for creating the test database.
Oracle doesn't have the concept of separate databases under the same
user, so a separate user is used; see _create_test_db(). The main user
is also needed for cleanup when testing is completed, so save its
credentials in the SAVED_USER/SAVED_PASSWORD key in the settings dict.
"""
real_settings = settings.DATABASES[self.connection.alias]
real_settings['SAVED_USER'] = self.connection.settings_dict['SAVED_USER'] = \
self.connection.settings_dict['USER']
real_settings['SAVED_PASSWORD'] = self.connection.settings_dict['SAVED_PASSWORD'] = \
self.connection.settings_dict['PASSWORD']
real_test_settings = real_settings['TEST']
test_settings = self.connection.settings_dict['TEST']
real_test_settings['USER'] = real_settings['USER'] = test_settings['USER'] = \
self.connection.settings_dict['USER'] = parameters['user']
real_settings['PASSWORD'] = self.connection.settings_dict['PASSWORD'] = parameters['password']
def set_as_test_mirror(self, primary_settings_dict):
"""
Set this database up to be used in testing as a mirror of a primary
database whose settings are given.
"""
self.connection.settings_dict['USER'] = primary_settings_dict['USER']
self.connection.settings_dict['PASSWORD'] = primary_settings_dict['PASSWORD']
def _handle_objects_preventing_db_destruction(self, cursor, parameters, verbosity, autoclobber):
# There are objects in the test tablespace which prevent dropping it
# The easy fix is to drop the test user -- but are we allowed to do so?
self.log(
'There are objects in the old test database which prevent its destruction.\n'
'If they belong to the test user, deleting the user will allow the test '
'database to be recreated.\n'
'Otherwise, you will need to find and remove each of these objects, '
'or use a different tablespace.\n'
)
if self._test_user_create():
if not autoclobber:
confirm = input("Type 'yes' to delete user %s: " % parameters['user'])
if autoclobber or confirm == 'yes':
try:
if verbosity >= 1:
self.log('Destroying old test user...')
self._destroy_test_user(cursor, parameters, verbosity)
except Exception as e:
self.log('Got an error destroying the test user: %s' % e)
sys.exit(2)
try:
if verbosity >= 1:
self.log("Destroying old test database for alias '%s'..." % self.connection.alias)
self._execute_test_db_destruction(cursor, parameters, verbosity)
except Exception as e:
self.log('Got an error destroying the test database: %s' % e)
sys.exit(2)
else:
self.log('Tests cancelled -- test database cannot be recreated.')
sys.exit(1)
else:
self.log("Django is configured to use pre-existing test user '%s',"
" and will not attempt to delete it." % parameters['user'])
self.log('Tests cancelled -- test database cannot be recreated.')
sys.exit(1)
def _destroy_test_db(self, test_database_name, verbosity=1):
"""
Destroy a test database, prompting the user for confirmation if the
database already exists. Return the name of the test database created.
"""
self.connection.settings_dict['USER'] = self.connection.settings_dict['SAVED_USER']
self.connection.settings_dict['PASSWORD'] = self.connection.settings_dict['SAVED_PASSWORD']
self.connection.close()
parameters = self._get_test_db_params()
with self._maindb_connection.cursor() as cursor:
if self._test_user_create():
if verbosity >= 1:
self.log('Destroying test user...')
self._destroy_test_user(cursor, parameters, verbosity)
if self._test_database_create():
if verbosity >= 1:
self.log('Destroying test database tables...')
self._execute_test_db_destruction(cursor, parameters, verbosity)
self._maindb_connection.close()
def _execute_test_db_creation(self, cursor, parameters, verbosity, keepdb=False):
if verbosity >= 2:
self.log('_create_test_db(): dbname = %s' % parameters['user'])
if self._test_database_oracle_managed_files():
statements = [
"""
CREATE TABLESPACE %(tblspace)s
DATAFILE SIZE %(size)s
AUTOEXTEND ON NEXT %(extsize)s MAXSIZE %(maxsize)s
""",
"""
CREATE TEMPORARY TABLESPACE %(tblspace_temp)s
TEMPFILE SIZE %(size_tmp)s
AUTOEXTEND ON NEXT %(extsize_tmp)s MAXSIZE %(maxsize_tmp)s
""",
]
else:
statements = [
"""
CREATE TABLESPACE %(tblspace)s
DATAFILE '%(datafile)s' SIZE %(size)s REUSE
AUTOEXTEND ON NEXT %(extsize)s MAXSIZE %(maxsize)s
""",
"""
CREATE TEMPORARY TABLESPACE %(tblspace_temp)s
TEMPFILE '%(datafile_tmp)s' SIZE %(size_tmp)s REUSE
AUTOEXTEND ON NEXT %(extsize_tmp)s MAXSIZE %(maxsize_tmp)s
""",
]
# Ignore "tablespace already exists" error when keepdb is on.
acceptable_ora_err = 'ORA-01543' if keepdb else None
self._execute_allow_fail_statements(cursor, statements, parameters, verbosity, acceptable_ora_err)
def _create_test_user(self, cursor, parameters, verbosity, keepdb=False):
if verbosity >= 2:
self.log('_create_test_user(): username = %s' % parameters['user'])
statements = [
"""CREATE USER %(user)s
IDENTIFIED BY "%(password)s"
DEFAULT TABLESPACE %(tblspace)s
TEMPORARY TABLESPACE %(tblspace_temp)s
QUOTA UNLIMITED ON %(tblspace)s
""",
"""GRANT CREATE SESSION,
CREATE TABLE,
CREATE SEQUENCE,
CREATE PROCEDURE,
CREATE TRIGGER
TO %(user)s""",
]
# Ignore "user already exists" error when keepdb is on
acceptable_ora_err = 'ORA-01920' if keepdb else None
success = self._execute_allow_fail_statements(cursor, statements, parameters, verbosity, acceptable_ora_err)
# If the password was randomly generated, change the user accordingly.
if not success and self._test_settings_get('PASSWORD') is None:
set_password = 'ALTER USER %(user)s IDENTIFIED BY "%(password)s"'
self._execute_statements(cursor, [set_password], parameters, verbosity)
# Most test suites can be run without "create view" and
# "create materialized view" privileges. But some need it.
for object_type in ('VIEW', 'MATERIALIZED VIEW'):
extra = 'GRANT CREATE %(object_type)s TO %(user)s'
parameters['object_type'] = object_type
success = self._execute_allow_fail_statements(cursor, [extra], parameters, verbosity, 'ORA-01031')
if not success and verbosity >= 2:
self.log('Failed to grant CREATE %s permission to test user. This may be ok.' % object_type)
def _execute_test_db_destruction(self, cursor, parameters, verbosity):
if verbosity >= 2:
self.log('_execute_test_db_destruction(): dbname=%s' % parameters['user'])
statements = [
'DROP TABLESPACE %(tblspace)s INCLUDING CONTENTS AND DATAFILES CASCADE CONSTRAINTS',
'DROP TABLESPACE %(tblspace_temp)s INCLUDING CONTENTS AND DATAFILES CASCADE CONSTRAINTS',
]
self._execute_statements(cursor, statements, parameters, verbosity)
def _destroy_test_user(self, cursor, parameters, verbosity):
if verbosity >= 2:
self.log('_destroy_test_user(): user=%s' % parameters['user'])
self.log('Be patient. This can take some time...')
statements = [
'DROP USER %(user)s CASCADE',
]
self._execute_statements(cursor, statements, parameters, verbosity)
def _execute_statements(self, cursor, statements, parameters, verbosity, allow_quiet_fail=False):
for template in statements:
stmt = template % parameters
if verbosity >= 2:
print(stmt)
try:
cursor.execute(stmt)
except Exception as err:
if (not allow_quiet_fail) or verbosity >= 2:
self.log('Failed (%s)' % (err))
raise
def _execute_allow_fail_statements(self, cursor, statements, parameters, verbosity, acceptable_ora_err):
"""
Execute statements which are allowed to fail silently if the Oracle
error code given by `acceptable_ora_err` is raised. Return True if the
statements execute without an exception, or False otherwise.
"""
try:
# Statement can fail when acceptable_ora_err is not None
allow_quiet_fail = acceptable_ora_err is not None and len(acceptable_ora_err) > 0
self._execute_statements(cursor, statements, parameters, verbosity, allow_quiet_fail=allow_quiet_fail)
return True
except DatabaseError as err:
description = str(err)
if acceptable_ora_err is None or acceptable_ora_err not in description:
raise
return False
def _get_test_db_params(self):
return {
'dbname': self._test_database_name(),
'user': self._test_database_user(),
'password': self._test_database_passwd(),
'tblspace': self._test_database_tblspace(),
'tblspace_temp': self._test_database_tblspace_tmp(),
'datafile': self._test_database_tblspace_datafile(),
'datafile_tmp': self._test_database_tblspace_tmp_datafile(),
'maxsize': self._test_database_tblspace_maxsize(),
'maxsize_tmp': self._test_database_tblspace_tmp_maxsize(),
'size': self._test_database_tblspace_size(),
'size_tmp': self._test_database_tblspace_tmp_size(),
'extsize': self._test_database_tblspace_extsize(),
'extsize_tmp': self._test_database_tblspace_tmp_extsize(),
}
def _test_settings_get(self, key, default=None, prefixed=None):
"""
Return a value from the test settings dict, or a given default, or a
prefixed entry from the main settings dict.
"""
settings_dict = self.connection.settings_dict
val = settings_dict['TEST'].get(key, default)
if val is None and prefixed:
val = TEST_DATABASE_PREFIX + settings_dict[prefixed]
return val
def _test_database_name(self):
return self._test_settings_get('NAME', prefixed='NAME')
def _test_database_create(self):
return self._test_settings_get('CREATE_DB', default=True)
def _test_user_create(self):
return self._test_settings_get('CREATE_USER', default=True)
def _test_database_user(self):
return self._test_settings_get('USER', prefixed='USER')
def _test_database_passwd(self):
password = self._test_settings_get('PASSWORD')
if password is None and self._test_user_create():
# Oracle passwords are limited to 30 chars and can't contain symbols.
password = get_random_string(30)
return password
def _test_database_tblspace(self):
return self._test_settings_get('TBLSPACE', prefixed='USER')
def _test_database_tblspace_tmp(self):
settings_dict = self.connection.settings_dict
return settings_dict['TEST'].get('TBLSPACE_TMP',
TEST_DATABASE_PREFIX + settings_dict['USER'] + '_temp')
def _test_database_tblspace_datafile(self):
tblspace = '%s.dbf' % self._test_database_tblspace()
return self._test_settings_get('DATAFILE', default=tblspace)
def _test_database_tblspace_tmp_datafile(self):
tblspace = '%s.dbf' % self._test_database_tblspace_tmp()
return self._test_settings_get('DATAFILE_TMP', default=tblspace)
def _test_database_tblspace_maxsize(self):
return self._test_settings_get('DATAFILE_MAXSIZE', default='500M')
def _test_database_tblspace_tmp_maxsize(self):
return self._test_settings_get('DATAFILE_TMP_MAXSIZE', default='500M')
def _test_database_tblspace_size(self):
return self._test_settings_get('DATAFILE_SIZE', default='50M')
def _test_database_tblspace_tmp_size(self):
return self._test_settings_get('DATAFILE_TMP_SIZE', default='50M')
def _test_database_tblspace_extsize(self):
return self._test_settings_get('DATAFILE_EXTSIZE', default='25M')
def _test_database_tblspace_tmp_extsize(self):
return self._test_settings_get('DATAFILE_TMP_EXTSIZE', default='25M')
def _test_database_oracle_managed_files(self):
return self._test_settings_get('ORACLE_MANAGED_FILES', default=False)
def _get_test_db_name(self):
"""
Return the 'production' DB name to get the test DB creation machinery
to work. This isn't a great deal in this case because DB names as
handled by Django don't have real counterparts in Oracle.
"""
return self.connection.settings_dict['NAME']
def test_db_signature(self):
settings_dict = self.connection.settings_dict
return (
settings_dict['HOST'],
settings_dict['PORT'],
settings_dict['ENGINE'],
settings_dict['NAME'],
self._test_database_user(),
)
|
db3f3e9061a29f22ee8729d8273a1abb9bdbf9f2bd117a9db4e3aa55da1c0131 | from django.db import ProgrammingError
from django.utils.functional import cached_property
class BaseDatabaseFeatures:
gis_enabled = False
allows_group_by_pk = False
allows_group_by_selected_pks = False
empty_fetchmany_value = []
update_can_self_select = True
# Does the backend distinguish between '' and None?
interprets_empty_strings_as_nulls = False
# Does the backend allow inserting duplicate NULL rows in a nullable
# unique field? All core backends implement this correctly, but other
# databases such as SQL Server do not.
supports_nullable_unique_constraints = True
# Does the backend allow inserting duplicate rows when a unique_together
# constraint exists and some fields are nullable but not all of them?
supports_partially_nullable_unique_constraints = True
# Does the backend support initially deferrable unique constraints?
supports_deferrable_unique_constraints = False
can_use_chunked_reads = True
can_return_columns_from_insert = False
can_return_rows_from_bulk_insert = False
has_bulk_insert = True
uses_savepoints = True
can_release_savepoints = False
# If True, don't use integer foreign keys referring to, e.g., positive
# integer primary keys.
related_fields_match_type = False
allow_sliced_subqueries_with_in = True
has_select_for_update = False
has_select_for_update_nowait = False
has_select_for_update_skip_locked = False
has_select_for_update_of = False
# Does the database's SELECT FOR UPDATE OF syntax require a column rather
# than a table?
select_for_update_of_column = False
# Does the default test database allow multiple connections?
# Usually an indication that the test database is in-memory
test_db_allows_multiple_connections = True
# Can an object be saved without an explicit primary key?
supports_unspecified_pk = False
# Can a fixture contain forward references? i.e., are
# FK constraints checked at the end of transaction, or
# at the end of each save operation?
supports_forward_references = True
# Does the backend truncate names properly when they are too long?
truncates_names = False
# Is there a REAL datatype in addition to floats/doubles?
has_real_datatype = False
supports_subqueries_in_group_by = True
# Is there a true datatype for uuid?
has_native_uuid_field = False
# Is there a true datatype for timedeltas?
has_native_duration_field = False
# Does the database driver supports same type temporal data subtraction
# by returning the type used to store duration field?
supports_temporal_subtraction = False
# Does the __regex lookup support backreferencing and grouping?
supports_regex_backreferencing = True
# Can date/datetime lookups be performed using a string?
supports_date_lookup_using_string = True
# Can datetimes with timezones be used?
supports_timezones = True
# Does the database have a copy of the zoneinfo database?
has_zoneinfo_database = True
# When performing a GROUP BY, is an ORDER BY NULL required
# to remove any ordering?
requires_explicit_null_ordering_when_grouping = False
# Does the backend order NULL values as largest or smallest?
nulls_order_largest = False
# Does the backend support NULLS FIRST and NULLS LAST in ORDER BY?
supports_order_by_nulls_modifier = True
# Does the backend orders NULLS FIRST by default?
order_by_nulls_first = False
# The database's limit on the number of query parameters.
max_query_params = None
# Can an object have an autoincrement primary key of 0? MySQL says No.
allows_auto_pk_0 = True
# Do we need to NULL a ForeignKey out, or can the constraint check be
# deferred
can_defer_constraint_checks = False
# date_interval_sql can properly handle mixed Date/DateTime fields and timedeltas
supports_mixed_date_datetime_comparisons = True
# Does the backend support tablespaces? Default to False because it isn't
# in the SQL standard.
supports_tablespaces = False
# Does the backend reset sequences between tests?
supports_sequence_reset = True
# Can the backend introspect the default value of a column?
can_introspect_default = True
# Confirm support for introspected foreign keys
# Every database can do this reliably, except MySQL,
# which can't do it for MyISAM tables
can_introspect_foreign_keys = True
# Can the backend introspect an AutoField, instead of an IntegerField?
can_introspect_autofield = False
# Can the backend introspect a BigIntegerField, instead of an IntegerField?
can_introspect_big_integer_field = True
# Can the backend introspect an BinaryField, instead of an TextField?
can_introspect_binary_field = True
# Can the backend introspect an DecimalField, instead of an FloatField?
can_introspect_decimal_field = True
# Can the backend introspect a DurationField, instead of a BigIntegerField?
can_introspect_duration_field = True
# Can the backend introspect an IPAddressField, instead of an CharField?
can_introspect_ip_address_field = False
# Can the backend introspect a PositiveIntegerField, instead of an IntegerField?
can_introspect_positive_integer_field = False
# Can the backend introspect a SmallIntegerField, instead of an IntegerField?
can_introspect_small_integer_field = False
# Can the backend introspect a TimeField, instead of a DateTimeField?
can_introspect_time_field = True
# Some backends may not be able to differentiate BigAutoField or
# SmallAutoField from other fields such as AutoField.
introspected_big_auto_field_type = 'BigAutoField'
introspected_small_auto_field_type = 'SmallAutoField'
# Some backends may not be able to differentiate BooleanField from other
# fields such as IntegerField.
introspected_boolean_field_type = 'BooleanField'
# Can the backend introspect the column order (ASC/DESC) for indexes?
supports_index_column_ordering = True
# Does the backend support introspection of materialized views?
can_introspect_materialized_views = False
# Support for the DISTINCT ON clause
can_distinct_on_fields = False
# Does the backend prevent running SQL queries in broken transactions?
atomic_transactions = True
# Can we roll back DDL in a transaction?
can_rollback_ddl = False
# Does it support operations requiring references rename in a transaction?
supports_atomic_references_rename = True
# Can we issue more than one ALTER COLUMN clause in an ALTER TABLE?
supports_combined_alters = False
# Does it support foreign keys?
supports_foreign_keys = True
# Can it create foreign key constraints inline when adding columns?
can_create_inline_fk = True
# Does it support CHECK constraints?
supports_column_check_constraints = True
supports_table_check_constraints = True
# Does the backend support introspection of CHECK constraints?
can_introspect_check_constraints = True
# Does the backend support 'pyformat' style ("... %(name)s ...", {'name': value})
# parameter passing? Note this can be provided by the backend even if not
# supported by the Python driver
supports_paramstyle_pyformat = True
# Does the backend require literal defaults, rather than parameterized ones?
requires_literal_defaults = False
# Does the backend require a connection reset after each material schema change?
connection_persists_old_columns = False
# What kind of error does the backend throw when accessing closed cursor?
closed_cursor_error_class = ProgrammingError
# Does 'a' LIKE 'A' match?
has_case_insensitive_like = True
# Suffix for backends that don't support "SELECT xxx;" queries.
bare_select_suffix = ''
# If NULL is implied on columns without needing to be explicitly specified
implied_column_null = False
# Does the backend support "select for update" queries with limit (and offset)?
supports_select_for_update_with_limit = True
# Does the backend ignore null expressions in GREATEST and LEAST queries unless
# every expression is null?
greatest_least_ignores_nulls = False
# Can the backend clone databases for parallel test execution?
# Defaults to False to allow third-party backends to opt-in.
can_clone_databases = False
# Does the backend consider table names with different casing to
# be equal?
ignores_table_name_case = False
# Place FOR UPDATE right after FROM clause. Used on MSSQL.
for_update_after_from = False
# Combinatorial flags
supports_select_union = True
supports_select_intersection = True
supports_select_difference = True
supports_slicing_ordering_in_compound = False
supports_parentheses_in_compound = True
# Does the database support SQL 2003 FILTER (WHERE ...) in aggregate
# expressions?
supports_aggregate_filter_clause = False
# Does the backend support indexing a TextField?
supports_index_on_text_field = True
# Does the backend support window expressions (expression OVER (...))?
supports_over_clause = False
supports_frame_range_fixed_distance = False
only_supports_unbounded_with_preceding_and_following = False
# Does the backend support CAST with precision?
supports_cast_with_precision = True
# How many second decimals does the database return when casting a value to
# a type with time?
time_cast_precision = 6
# SQL to create a procedure for use by the Django test suite. The
# functionality of the procedure isn't important.
create_test_procedure_without_params_sql = None
create_test_procedure_with_int_param_sql = None
# Does the backend support keyword parameters for cursor.callproc()?
supports_callproc_kwargs = False
# Convert CharField results from bytes to str in database functions.
db_functions_convert_bytes_to_str = False
# What formats does the backend EXPLAIN syntax support?
supported_explain_formats = set()
# Does DatabaseOperations.explain_query_prefix() raise ValueError if
# unknown kwargs are passed to QuerySet.explain()?
validates_explain_options = True
# Does the backend support the default parameter in lead() and lag()?
supports_default_in_lead_lag = True
# Does the backend support ignoring constraint or uniqueness errors during
# INSERT?
supports_ignore_conflicts = True
# Does this backend require casting the results of CASE expressions used
# in UPDATE statements to ensure the expression has the correct type?
requires_casted_case_in_updates = False
# Does the backend support partial indexes (CREATE INDEX ... WHERE ...)?
supports_partial_indexes = True
supports_functions_in_partial_indexes = True
# Does the database allow more than one constraint or index on the same
# field(s)?
allows_multiple_constraints_on_same_fields = True
# Does the backend support boolean expressions in the SELECT clause?
supports_boolean_expr_in_select_clause = True
# Does the backend support JSONField?
supports_json_field = True
# Can the backend introspect a JSONField?
can_introspect_json_field = True
# Does the backend support primitives in JSONField?
supports_primitives_in_json_field = True
# Is there a true datatype for JSON?
has_native_json_field = False
def __init__(self, connection):
self.connection = connection
@cached_property
def supports_explaining_query_execution(self):
"""Does this backend support explaining query execution?"""
return self.connection.ops.explain_prefix is not None
@cached_property
def supports_transactions(self):
"""Confirm support for transactions."""
with self.connection.cursor() as cursor:
cursor.execute('CREATE TABLE ROLLBACK_TEST (X INT)')
self.connection.set_autocommit(False)
cursor.execute('INSERT INTO ROLLBACK_TEST (X) VALUES (8)')
self.connection.rollback()
self.connection.set_autocommit(True)
cursor.execute('SELECT COUNT(X) FROM ROLLBACK_TEST')
count, = cursor.fetchone()
cursor.execute('DROP TABLE ROLLBACK_TEST')
return count == 0
def allows_group_by_selected_pks_on_model(self, model):
if not self.allows_group_by_selected_pks:
return False
return model._meta.managed
|
8e6c06155e654eeb27ffdf7485e81037f2cc45d0a4a47c0e4507d05cd01bf7b6 | from collections import namedtuple
# Structure returned by DatabaseIntrospection.get_table_list()
TableInfo = namedtuple('TableInfo', ['name', 'type'])
# Structure returned by the DB-API cursor.description interface (PEP 249)
FieldInfo = namedtuple('FieldInfo', 'name type_code display_size internal_size precision scale null_ok default')
class BaseDatabaseIntrospection:
"""Encapsulate backend-specific introspection utilities."""
data_types_reverse = {}
def __init__(self, connection):
self.connection = connection
def get_field_type(self, data_type, description):
"""
Hook for a database backend to use the cursor description to
match a Django field type to a database column.
For Oracle, the column data_type on its own is insufficient to
distinguish between a FloatField and IntegerField, for example.
"""
return self.data_types_reverse[data_type]
def identifier_converter(self, name):
"""
Apply a conversion to the identifier for the purposes of comparison.
The default identifier converter is for case sensitive comparison.
"""
return name
def table_names(self, cursor=None, include_views=False):
"""
Return a list of names of all tables that exist in the database.
Sort the returned table list by Python's default sorting. Do NOT use
the database's ORDER BY here to avoid subtle differences in sorting
order between databases.
"""
def get_names(cursor):
return sorted(ti.name for ti in self.get_table_list(cursor)
if include_views or ti.type == 't')
if cursor is None:
with self.connection.cursor() as cursor:
return get_names(cursor)
return get_names(cursor)
def get_table_list(self, cursor):
"""
Return an unsorted list of TableInfo named tuples of all tables and
views that exist in the database.
"""
raise NotImplementedError('subclasses of BaseDatabaseIntrospection may require a get_table_list() method')
def get_table_description(self, cursor, table_name):
"""
Return a description of the table with the DB-API cursor.description
interface.
"""
raise NotImplementedError(
'subclasses of BaseDatabaseIntrospection may require a '
'get_table_description() method.'
)
def get_migratable_models(self):
from django.apps import apps
from django.db import router
return (
model
for app_config in apps.get_app_configs()
for model in router.get_migratable_models(app_config, self.connection.alias)
if model._meta.can_migrate(self.connection)
)
def django_table_names(self, only_existing=False, include_views=True):
"""
Return a list of all table names that have associated Django models and
are in INSTALLED_APPS.
If only_existing is True, include only the tables in the database.
"""
tables = set()
for model in self.get_migratable_models():
if not model._meta.managed:
continue
tables.add(model._meta.db_table)
tables.update(
f.m2m_db_table() for f in model._meta.local_many_to_many
if f.remote_field.through._meta.managed
)
tables = list(tables)
if only_existing:
existing_tables = set(self.table_names(include_views=include_views))
tables = [
t
for t in tables
if self.identifier_converter(t) in existing_tables
]
return tables
def installed_models(self, tables):
"""
Return a set of all models represented by the provided list of table
names.
"""
tables = set(map(self.identifier_converter, tables))
return {
m for m in self.get_migratable_models()
if self.identifier_converter(m._meta.db_table) in tables
}
def sequence_list(self):
"""
Return a list of information about all DB sequences for all models in
all apps.
"""
sequence_list = []
with self.connection.cursor() as cursor:
for model in self.get_migratable_models():
if not model._meta.managed:
continue
if model._meta.swapped:
continue
sequence_list.extend(self.get_sequences(cursor, model._meta.db_table, model._meta.local_fields))
for f in model._meta.local_many_to_many:
# If this is an m2m using an intermediate table,
# we don't need to reset the sequence.
if f.remote_field.through._meta.auto_created:
sequence = self.get_sequences(cursor, f.m2m_db_table())
sequence_list.extend(sequence or [{'table': f.m2m_db_table(), 'column': None}])
return sequence_list
def get_sequences(self, cursor, table_name, table_fields=()):
"""
Return a list of introspected sequences for table_name. Each sequence
is a dict: {'table': <table_name>, 'column': <column_name>}. An optional
'name' key can be added if the backend supports named sequences.
"""
raise NotImplementedError('subclasses of BaseDatabaseIntrospection may require a get_sequences() method')
def get_relations(self, cursor, table_name):
"""
Return a dictionary of
{field_name: (field_name_other_table, other_table)} representing all
relationships to the given table.
"""
raise NotImplementedError(
'subclasses of BaseDatabaseIntrospection may require a '
'get_relations() method.'
)
def get_key_columns(self, cursor, table_name):
"""
Backends can override this to return a list of:
(column_name, referenced_table_name, referenced_column_name)
for all key columns in given table.
"""
raise NotImplementedError('subclasses of BaseDatabaseIntrospection may require a get_key_columns() method')
def get_primary_key_column(self, cursor, table_name):
"""
Return the name of the primary key column for the given table.
"""
for constraint in self.get_constraints(cursor, table_name).values():
if constraint['primary_key']:
return constraint['columns'][0]
return None
def get_constraints(self, cursor, table_name):
"""
Retrieve any constraints or keys (unique, pk, fk, check, index)
across one or more columns.
Return a dict mapping constraint names to their attributes,
where attributes is a dict with keys:
* columns: List of columns this covers
* primary_key: True if primary key, False otherwise
* unique: True if this is a unique constraint, False otherwise
* foreign_key: (table, column) of target, or None
* check: True if check constraint, False otherwise
* index: True if index, False otherwise.
* orders: The order (ASC/DESC) defined for the columns of indexes
* type: The type of the index (btree, hash, etc.)
Some backends may return special constraint names that don't exist
if they don't name constraints of a certain type (e.g. SQLite)
"""
raise NotImplementedError('subclasses of BaseDatabaseIntrospection may require a get_constraints() method')
|
c9570ce8c5d5f060f224162e16a4acce72685c9ba5ec72e4b0ca3db6607450e1 | import copy
import threading
import time
import warnings
from collections import deque
from contextlib import contextmanager
import _thread
import pytz
from django.conf import settings
from django.core.exceptions import ImproperlyConfigured
from django.db import DEFAULT_DB_ALIAS, DatabaseError
from django.db.backends import utils
from django.db.backends.base.validation import BaseDatabaseValidation
from django.db.backends.signals import connection_created
from django.db.transaction import TransactionManagementError
from django.db.utils import DatabaseErrorWrapper
from django.utils import timezone
from django.utils.asyncio import async_unsafe
from django.utils.functional import cached_property
NO_DB_ALIAS = '__no_db__'
class BaseDatabaseWrapper:
"""Represent a database connection."""
# Mapping of Field objects to their column types.
data_types = {}
# Mapping of Field objects to their SQL suffix such as AUTOINCREMENT.
data_types_suffix = {}
# Mapping of Field objects to their SQL for CHECK constraints.
data_type_check_constraints = {}
ops = None
vendor = 'unknown'
display_name = 'unknown'
SchemaEditorClass = None
# Classes instantiated in __init__().
client_class = None
creation_class = None
features_class = None
introspection_class = None
ops_class = None
validation_class = BaseDatabaseValidation
queries_limit = 9000
def __init__(self, settings_dict, alias=DEFAULT_DB_ALIAS):
# Connection related attributes.
# The underlying database connection.
self.connection = None
# `settings_dict` should be a dictionary containing keys such as
# NAME, USER, etc. It's called `settings_dict` instead of `settings`
# to disambiguate it from Django settings modules.
self.settings_dict = settings_dict
self.alias = alias
# Query logging in debug mode or when explicitly enabled.
self.queries_log = deque(maxlen=self.queries_limit)
self.force_debug_cursor = False
# Transaction related attributes.
# Tracks if the connection is in autocommit mode. Per PEP 249, by
# default, it isn't.
self.autocommit = False
# Tracks if the connection is in a transaction managed by 'atomic'.
self.in_atomic_block = False
# Increment to generate unique savepoint ids.
self.savepoint_state = 0
# List of savepoints created by 'atomic'.
self.savepoint_ids = []
# Tracks if the outermost 'atomic' block should commit on exit,
# ie. if autocommit was active on entry.
self.commit_on_exit = True
# Tracks if the transaction should be rolled back to the next
# available savepoint because of an exception in an inner block.
self.needs_rollback = False
# Connection termination related attributes.
self.close_at = None
self.closed_in_transaction = False
self.errors_occurred = False
# Thread-safety related attributes.
self._thread_sharing_lock = threading.Lock()
self._thread_sharing_count = 0
self._thread_ident = _thread.get_ident()
# A list of no-argument functions to run when the transaction commits.
# Each entry is an (sids, func) tuple, where sids is a set of the
# active savepoint IDs when this function was registered.
self.run_on_commit = []
# Should we run the on-commit hooks the next time set_autocommit(True)
# is called?
self.run_commit_hooks_on_set_autocommit_on = False
# A stack of wrappers to be invoked around execute()/executemany()
# calls. Each entry is a function taking five arguments: execute, sql,
# params, many, and context. It's the function's responsibility to
# call execute(sql, params, many, context).
self.execute_wrappers = []
self.client = self.client_class(self)
self.creation = self.creation_class(self)
self.features = self.features_class(self)
self.introspection = self.introspection_class(self)
self.ops = self.ops_class(self)
self.validation = self.validation_class(self)
def ensure_timezone(self):
"""
Ensure the connection's timezone is set to `self.timezone_name` and
return whether it changed or not.
"""
return False
@cached_property
def timezone(self):
"""
Return a tzinfo of the database connection time zone.
This is only used when time zone support is enabled. When a datetime is
read from the database, it is always returned in this time zone.
When the database backend supports time zones, it doesn't matter which
time zone Django uses, as long as aware datetimes are used everywhere.
Other users connecting to the database can choose their own time zone.
When the database backend doesn't support time zones, the time zone
Django uses may be constrained by the requirements of other users of
the database.
"""
if not settings.USE_TZ:
return None
elif self.settings_dict['TIME_ZONE'] is None:
return timezone.utc
else:
return pytz.timezone(self.settings_dict['TIME_ZONE'])
@cached_property
def timezone_name(self):
"""
Name of the time zone of the database connection.
"""
if not settings.USE_TZ:
return settings.TIME_ZONE
elif self.settings_dict['TIME_ZONE'] is None:
return 'UTC'
else:
return self.settings_dict['TIME_ZONE']
@property
def queries_logged(self):
return self.force_debug_cursor or settings.DEBUG
@property
def queries(self):
if len(self.queries_log) == self.queries_log.maxlen:
warnings.warn(
"Limit for query logging exceeded, only the last {} queries "
"will be returned.".format(self.queries_log.maxlen))
return list(self.queries_log)
# ##### Backend-specific methods for creating connections and cursors #####
def get_connection_params(self):
"""Return a dict of parameters suitable for get_new_connection."""
raise NotImplementedError('subclasses of BaseDatabaseWrapper may require a get_connection_params() method')
def get_new_connection(self, conn_params):
"""Open a connection to the database."""
raise NotImplementedError('subclasses of BaseDatabaseWrapper may require a get_new_connection() method')
def init_connection_state(self):
"""Initialize the database connection settings."""
raise NotImplementedError('subclasses of BaseDatabaseWrapper may require an init_connection_state() method')
def create_cursor(self, name=None):
"""Create a cursor. Assume that a connection is established."""
raise NotImplementedError('subclasses of BaseDatabaseWrapper may require a create_cursor() method')
# ##### Backend-specific methods for creating connections #####
@async_unsafe
def connect(self):
"""Connect to the database. Assume that the connection is closed."""
# Check for invalid configurations.
self.check_settings()
# In case the previous connection was closed while in an atomic block
self.in_atomic_block = False
self.savepoint_ids = []
self.needs_rollback = False
# Reset parameters defining when to close the connection
max_age = self.settings_dict['CONN_MAX_AGE']
self.close_at = None if max_age is None else time.monotonic() + max_age
self.closed_in_transaction = False
self.errors_occurred = False
# Establish the connection
conn_params = self.get_connection_params()
self.connection = self.get_new_connection(conn_params)
self.set_autocommit(self.settings_dict['AUTOCOMMIT'])
self.init_connection_state()
connection_created.send(sender=self.__class__, connection=self)
self.run_on_commit = []
def check_settings(self):
if self.settings_dict['TIME_ZONE'] is not None and not settings.USE_TZ:
raise ImproperlyConfigured(
"Connection '%s' cannot set TIME_ZONE because USE_TZ is False."
% self.alias
)
@async_unsafe
def ensure_connection(self):
"""Guarantee that a connection to the database is established."""
if self.connection is None:
with self.wrap_database_errors:
self.connect()
# ##### Backend-specific wrappers for PEP-249 connection methods #####
def _prepare_cursor(self, cursor):
"""
Validate the connection is usable and perform database cursor wrapping.
"""
self.validate_thread_sharing()
if self.queries_logged:
wrapped_cursor = self.make_debug_cursor(cursor)
else:
wrapped_cursor = self.make_cursor(cursor)
return wrapped_cursor
def _cursor(self, name=None):
self.ensure_connection()
with self.wrap_database_errors:
return self._prepare_cursor(self.create_cursor(name))
def _commit(self):
if self.connection is not None:
with self.wrap_database_errors:
return self.connection.commit()
def _rollback(self):
if self.connection is not None:
with self.wrap_database_errors:
return self.connection.rollback()
def _close(self):
if self.connection is not None:
with self.wrap_database_errors:
return self.connection.close()
# ##### Generic wrappers for PEP-249 connection methods #####
@async_unsafe
def cursor(self):
"""Create a cursor, opening a connection if necessary."""
return self._cursor()
@async_unsafe
def commit(self):
"""Commit a transaction and reset the dirty flag."""
self.validate_thread_sharing()
self.validate_no_atomic_block()
self._commit()
# A successful commit means that the database connection works.
self.errors_occurred = False
self.run_commit_hooks_on_set_autocommit_on = True
@async_unsafe
def rollback(self):
"""Roll back a transaction and reset the dirty flag."""
self.validate_thread_sharing()
self.validate_no_atomic_block()
self._rollback()
# A successful rollback means that the database connection works.
self.errors_occurred = False
self.needs_rollback = False
self.run_on_commit = []
@async_unsafe
def close(self):
"""Close the connection to the database."""
self.validate_thread_sharing()
self.run_on_commit = []
# Don't call validate_no_atomic_block() to avoid making it difficult
# to get rid of a connection in an invalid state. The next connect()
# will reset the transaction state anyway.
if self.closed_in_transaction or self.connection is None:
return
try:
self._close()
finally:
if self.in_atomic_block:
self.closed_in_transaction = True
self.needs_rollback = True
else:
self.connection = None
# ##### Backend-specific savepoint management methods #####
def _savepoint(self, sid):
with self.cursor() as cursor:
cursor.execute(self.ops.savepoint_create_sql(sid))
def _savepoint_rollback(self, sid):
with self.cursor() as cursor:
cursor.execute(self.ops.savepoint_rollback_sql(sid))
def _savepoint_commit(self, sid):
with self.cursor() as cursor:
cursor.execute(self.ops.savepoint_commit_sql(sid))
def _savepoint_allowed(self):
# Savepoints cannot be created outside a transaction
return self.features.uses_savepoints and not self.get_autocommit()
# ##### Generic savepoint management methods #####
@async_unsafe
def savepoint(self):
"""
Create a savepoint inside the current transaction. Return an
identifier for the savepoint that will be used for the subsequent
rollback or commit. Do nothing if savepoints are not supported.
"""
if not self._savepoint_allowed():
return
thread_ident = _thread.get_ident()
tid = str(thread_ident).replace('-', '')
self.savepoint_state += 1
sid = "s%s_x%d" % (tid, self.savepoint_state)
self.validate_thread_sharing()
self._savepoint(sid)
return sid
@async_unsafe
def savepoint_rollback(self, sid):
"""
Roll back to a savepoint. Do nothing if savepoints are not supported.
"""
if not self._savepoint_allowed():
return
self.validate_thread_sharing()
self._savepoint_rollback(sid)
# Remove any callbacks registered while this savepoint was active.
self.run_on_commit = [
(sids, func) for (sids, func) in self.run_on_commit if sid not in sids
]
@async_unsafe
def savepoint_commit(self, sid):
"""
Release a savepoint. Do nothing if savepoints are not supported.
"""
if not self._savepoint_allowed():
return
self.validate_thread_sharing()
self._savepoint_commit(sid)
@async_unsafe
def clean_savepoints(self):
"""
Reset the counter used to generate unique savepoint ids in this thread.
"""
self.savepoint_state = 0
# ##### Backend-specific transaction management methods #####
def _set_autocommit(self, autocommit):
"""
Backend-specific implementation to enable or disable autocommit.
"""
raise NotImplementedError('subclasses of BaseDatabaseWrapper may require a _set_autocommit() method')
# ##### Generic transaction management methods #####
def get_autocommit(self):
"""Get the autocommit state."""
self.ensure_connection()
return self.autocommit
def set_autocommit(self, autocommit, force_begin_transaction_with_broken_autocommit=False):
"""
Enable or disable autocommit.
The usual way to start a transaction is to turn autocommit off.
SQLite does not properly start a transaction when disabling
autocommit. To avoid this buggy behavior and to actually enter a new
transaction, an explicit BEGIN is required. Using
force_begin_transaction_with_broken_autocommit=True will issue an
explicit BEGIN with SQLite. This option will be ignored for other
backends.
"""
self.validate_no_atomic_block()
self.ensure_connection()
start_transaction_under_autocommit = (
force_begin_transaction_with_broken_autocommit and not autocommit and
hasattr(self, '_start_transaction_under_autocommit')
)
if start_transaction_under_autocommit:
self._start_transaction_under_autocommit()
else:
self._set_autocommit(autocommit)
self.autocommit = autocommit
if autocommit and self.run_commit_hooks_on_set_autocommit_on:
self.run_and_clear_commit_hooks()
self.run_commit_hooks_on_set_autocommit_on = False
def get_rollback(self):
"""Get the "needs rollback" flag -- for *advanced use* only."""
if not self.in_atomic_block:
raise TransactionManagementError(
"The rollback flag doesn't work outside of an 'atomic' block.")
return self.needs_rollback
def set_rollback(self, rollback):
"""
Set or unset the "needs rollback" flag -- for *advanced use* only.
"""
if not self.in_atomic_block:
raise TransactionManagementError(
"The rollback flag doesn't work outside of an 'atomic' block.")
self.needs_rollback = rollback
def validate_no_atomic_block(self):
"""Raise an error if an atomic block is active."""
if self.in_atomic_block:
raise TransactionManagementError(
"This is forbidden when an 'atomic' block is active.")
def validate_no_broken_transaction(self):
if self.needs_rollback:
raise TransactionManagementError(
"An error occurred in the current transaction. You can't "
"execute queries until the end of the 'atomic' block.")
# ##### Foreign key constraints checks handling #####
@contextmanager
def constraint_checks_disabled(self):
"""
Disable foreign key constraint checking.
"""
disabled = self.disable_constraint_checking()
try:
yield
finally:
if disabled:
self.enable_constraint_checking()
def disable_constraint_checking(self):
"""
Backends can implement as needed to temporarily disable foreign key
constraint checking. Should return True if the constraints were
disabled and will need to be reenabled.
"""
return False
def enable_constraint_checking(self):
"""
Backends can implement as needed to re-enable foreign key constraint
checking.
"""
pass
def check_constraints(self, table_names=None):
"""
Backends can override this method if they can apply constraint
checking (e.g. via "SET CONSTRAINTS ALL IMMEDIATE"). Should raise an
IntegrityError if any invalid foreign key references are encountered.
"""
pass
# ##### Connection termination handling #####
def is_usable(self):
"""
Test if the database connection is usable.
This method may assume that self.connection is not None.
Actual implementations should take care not to raise exceptions
as that may prevent Django from recycling unusable connections.
"""
raise NotImplementedError(
"subclasses of BaseDatabaseWrapper may require an is_usable() method")
def close_if_unusable_or_obsolete(self):
"""
Close the current connection if unrecoverable errors have occurred
or if it outlived its maximum age.
"""
if self.connection is not None:
# If the application didn't restore the original autocommit setting,
# don't take chances, drop the connection.
if self.get_autocommit() != self.settings_dict['AUTOCOMMIT']:
self.close()
return
# If an exception other than DataError or IntegrityError occurred
# since the last commit / rollback, check if the connection works.
if self.errors_occurred:
if self.is_usable():
self.errors_occurred = False
else:
self.close()
return
if self.close_at is not None and time.monotonic() >= self.close_at:
self.close()
return
# ##### Thread safety handling #####
@property
def allow_thread_sharing(self):
with self._thread_sharing_lock:
return self._thread_sharing_count > 0
def inc_thread_sharing(self):
with self._thread_sharing_lock:
self._thread_sharing_count += 1
def dec_thread_sharing(self):
with self._thread_sharing_lock:
if self._thread_sharing_count <= 0:
raise RuntimeError('Cannot decrement the thread sharing count below zero.')
self._thread_sharing_count -= 1
def validate_thread_sharing(self):
"""
Validate that the connection isn't accessed by another thread than the
one which originally created it, unless the connection was explicitly
authorized to be shared between threads (via the `inc_thread_sharing()`
method). Raise an exception if the validation fails.
"""
if not (self.allow_thread_sharing or self._thread_ident == _thread.get_ident()):
raise DatabaseError(
"DatabaseWrapper objects created in a "
"thread can only be used in that same thread. The object "
"with alias '%s' was created in thread id %s and this is "
"thread id %s."
% (self.alias, self._thread_ident, _thread.get_ident())
)
# ##### Miscellaneous #####
def prepare_database(self):
"""
Hook to do any database check or preparation, generally called before
migrating a project or an app.
"""
pass
@cached_property
def wrap_database_errors(self):
"""
Context manager and decorator that re-throws backend-specific database
exceptions using Django's common wrappers.
"""
return DatabaseErrorWrapper(self)
def chunked_cursor(self):
"""
Return a cursor that tries to avoid caching in the database (if
supported by the database), otherwise return a regular cursor.
"""
return self.cursor()
def make_debug_cursor(self, cursor):
"""Create a cursor that logs all queries in self.queries_log."""
return utils.CursorDebugWrapper(cursor, self)
def make_cursor(self, cursor):
"""Create a cursor without debug logging."""
return utils.CursorWrapper(cursor, self)
@contextmanager
def temporary_connection(self):
"""
Context manager that ensures that a connection is established, and
if it opened one, closes it to avoid leaving a dangling connection.
This is useful for operations outside of the request-response cycle.
Provide a cursor: with self.temporary_connection() as cursor: ...
"""
must_close = self.connection is None
try:
with self.cursor() as cursor:
yield cursor
finally:
if must_close:
self.close()
@contextmanager
def _nodb_cursor(self):
"""
Return a cursor from an alternative connection to be used when there is
no need to access the main database, specifically for test db
creation/deletion. This also prevents the production database from
being exposed to potential child threads while (or after) the test
database is destroyed. Refs #10868, #17786, #16969.
"""
conn = self.__class__({**self.settings_dict, 'NAME': None}, alias=NO_DB_ALIAS)
try:
with conn.cursor() as cursor:
yield cursor
finally:
conn.close()
def schema_editor(self, *args, **kwargs):
"""
Return a new instance of this backend's SchemaEditor.
"""
if self.SchemaEditorClass is None:
raise NotImplementedError(
'The SchemaEditorClass attribute of this database wrapper is still None')
return self.SchemaEditorClass(self, *args, **kwargs)
def on_commit(self, func):
if self.in_atomic_block:
# Transaction in progress; save for execution on commit.
self.run_on_commit.append((set(self.savepoint_ids), func))
elif not self.get_autocommit():
raise TransactionManagementError('on_commit() cannot be used in manual transaction management')
else:
# No transaction in progress and in autocommit mode; execute
# immediately.
func()
def run_and_clear_commit_hooks(self):
self.validate_no_atomic_block()
current_run_on_commit = self.run_on_commit
self.run_on_commit = []
while current_run_on_commit:
sids, func = current_run_on_commit.pop(0)
func()
@contextmanager
def execute_wrapper(self, wrapper):
"""
Return a context manager under which the wrapper is applied to suitable
database query executions.
"""
self.execute_wrappers.append(wrapper)
try:
yield
finally:
self.execute_wrappers.pop()
def copy(self, alias=None):
"""
Return a copy of this connection.
For tests that require two connections to the same database.
"""
settings_dict = copy.deepcopy(self.settings_dict)
if alias is None:
alias = self.alias
return type(self)(settings_dict, alias)
|
eb9bea832a5f9406948e75f8d95ec570c707046deef86606592254ad68bbbac5 | import datetime
import decimal
from importlib import import_module
import sqlparse
from django.conf import settings
from django.db import NotSupportedError, transaction
from django.db.backends import utils
from django.utils import timezone
from django.utils.encoding import force_str
class BaseDatabaseOperations:
"""
Encapsulate backend-specific differences, such as the way a backend
performs ordering or calculates the ID of a recently-inserted row.
"""
compiler_module = "django.db.models.sql.compiler"
# Integer field safe ranges by `internal_type` as documented
# in docs/ref/models/fields.txt.
integer_field_ranges = {
'SmallIntegerField': (-32768, 32767),
'IntegerField': (-2147483648, 2147483647),
'BigIntegerField': (-9223372036854775808, 9223372036854775807),
'PositiveBigIntegerField': (0, 9223372036854775807),
'PositiveSmallIntegerField': (0, 32767),
'PositiveIntegerField': (0, 2147483647),
'SmallAutoField': (-32768, 32767),
'AutoField': (-2147483648, 2147483647),
'BigAutoField': (-9223372036854775808, 9223372036854775807),
}
set_operators = {
'union': 'UNION',
'intersection': 'INTERSECT',
'difference': 'EXCEPT',
}
# Mapping of Field.get_internal_type() (typically the model field's class
# name) to the data type to use for the Cast() function, if different from
# DatabaseWrapper.data_types.
cast_data_types = {}
# CharField data type if the max_length argument isn't provided.
cast_char_field_without_max_length = None
# Start and end points for window expressions.
PRECEDING = 'PRECEDING'
FOLLOWING = 'FOLLOWING'
UNBOUNDED_PRECEDING = 'UNBOUNDED ' + PRECEDING
UNBOUNDED_FOLLOWING = 'UNBOUNDED ' + FOLLOWING
CURRENT_ROW = 'CURRENT ROW'
# Prefix for EXPLAIN queries, or None EXPLAIN isn't supported.
explain_prefix = None
def __init__(self, connection):
self.connection = connection
self._cache = None
def autoinc_sql(self, table, column):
"""
Return any SQL needed to support auto-incrementing primary keys, or
None if no SQL is necessary.
This SQL is executed when a table is created.
"""
return None
def bulk_batch_size(self, fields, objs):
"""
Return the maximum allowed batch size for the backend. The fields
are the fields going to be inserted in the batch, the objs contains
all the objects to be inserted.
"""
return len(objs)
def cache_key_culling_sql(self):
"""
Return an SQL query that retrieves the first cache key greater than the
n smallest.
This is used by the 'db' cache backend to determine where to start
culling.
"""
return "SELECT cache_key FROM %s ORDER BY cache_key LIMIT 1 OFFSET %%s"
def unification_cast_sql(self, output_field):
"""
Given a field instance, return the SQL that casts the result of a union
to that type. The resulting string should contain a '%s' placeholder
for the expression being cast.
"""
return '%s'
def date_extract_sql(self, lookup_type, field_name):
"""
Given a lookup_type of 'year', 'month', or 'day', return the SQL that
extracts a value from the given date field field_name.
"""
raise NotImplementedError('subclasses of BaseDatabaseOperations may require a date_extract_sql() method')
def date_interval_sql(self, timedelta):
"""
Implement the date interval functionality for expressions.
"""
raise NotImplementedError('subclasses of BaseDatabaseOperations may require a date_interval_sql() method')
def date_trunc_sql(self, lookup_type, field_name):
"""
Given a lookup_type of 'year', 'month', or 'day', return the SQL that
truncates the given date field field_name to a date object with only
the given specificity.
"""
raise NotImplementedError('subclasses of BaseDatabaseOperations may require a date_trunc_sql() method.')
def datetime_cast_date_sql(self, field_name, tzname):
"""
Return the SQL to cast a datetime value to date value.
"""
raise NotImplementedError(
'subclasses of BaseDatabaseOperations may require a '
'datetime_cast_date_sql() method.'
)
def datetime_cast_time_sql(self, field_name, tzname):
"""
Return the SQL to cast a datetime value to time value.
"""
raise NotImplementedError('subclasses of BaseDatabaseOperations may require a datetime_cast_time_sql() method')
def datetime_extract_sql(self, lookup_type, field_name, tzname):
"""
Given a lookup_type of 'year', 'month', 'day', 'hour', 'minute', or
'second', return the SQL that extracts a value from the given
datetime field field_name.
"""
raise NotImplementedError('subclasses of BaseDatabaseOperations may require a datetime_extract_sql() method')
def datetime_trunc_sql(self, lookup_type, field_name, tzname):
"""
Given a lookup_type of 'year', 'month', 'day', 'hour', 'minute', or
'second', return the SQL that truncates the given datetime field
field_name to a datetime object with only the given specificity.
"""
raise NotImplementedError('subclasses of BaseDatabaseOperations may require a datetime_trunc_sql() method')
def time_trunc_sql(self, lookup_type, field_name):
"""
Given a lookup_type of 'hour', 'minute' or 'second', return the SQL
that truncates the given time field field_name to a time object with
only the given specificity.
"""
raise NotImplementedError('subclasses of BaseDatabaseOperations may require a time_trunc_sql() method')
def time_extract_sql(self, lookup_type, field_name):
"""
Given a lookup_type of 'hour', 'minute', or 'second', return the SQL
that extracts a value from the given time field field_name.
"""
return self.date_extract_sql(lookup_type, field_name)
def json_cast_text_sql(self, field_name):
"""Return the SQL to cast a JSON value to text value."""
raise NotImplementedError(
'subclasses of BaseDatabaseOperations may require a '
'json_cast_text_sql() method'
)
def deferrable_sql(self):
"""
Return the SQL to make a constraint "initially deferred" during a
CREATE TABLE statement.
"""
return ''
def distinct_sql(self, fields, params):
"""
Return an SQL DISTINCT clause which removes duplicate rows from the
result set. If any fields are given, only check the given fields for
duplicates.
"""
if fields:
raise NotSupportedError('DISTINCT ON fields is not supported by this database backend')
else:
return ['DISTINCT'], []
def fetch_returned_insert_columns(self, cursor, returning_params):
"""
Given a cursor object that has just performed an INSERT...RETURNING
statement into a table, return the newly created data.
"""
return cursor.fetchone()
def field_cast_sql(self, db_type, internal_type):
"""
Given a column type (e.g. 'BLOB', 'VARCHAR') and an internal type
(e.g. 'GenericIPAddressField'), return the SQL to cast it before using
it in a WHERE statement. The resulting string should contain a '%s'
placeholder for the column being searched against.
"""
return '%s'
def force_no_ordering(self):
"""
Return a list used in the "ORDER BY" clause to force no ordering at
all. Return an empty list to include nothing in the ordering.
"""
return []
def for_update_sql(self, nowait=False, skip_locked=False, of=()):
"""
Return the FOR UPDATE SQL clause to lock rows for an update operation.
"""
return 'FOR UPDATE%s%s%s' % (
' OF %s' % ', '.join(of) if of else '',
' NOWAIT' if nowait else '',
' SKIP LOCKED' if skip_locked else '',
)
def _get_limit_offset_params(self, low_mark, high_mark):
offset = low_mark or 0
if high_mark is not None:
return (high_mark - offset), offset
elif offset:
return self.connection.ops.no_limit_value(), offset
return None, offset
def limit_offset_sql(self, low_mark, high_mark):
"""Return LIMIT/OFFSET SQL clause."""
limit, offset = self._get_limit_offset_params(low_mark, high_mark)
return ' '.join(sql for sql in (
('LIMIT %d' % limit) if limit else None,
('OFFSET %d' % offset) if offset else None,
) if sql)
def last_executed_query(self, cursor, sql, params):
"""
Return a string of the query last executed by the given cursor, with
placeholders replaced with actual values.
`sql` is the raw query containing placeholders and `params` is the
sequence of parameters. These are used by default, but this method
exists for database backends to provide a better implementation
according to their own quoting schemes.
"""
# Convert params to contain string values.
def to_string(s):
return force_str(s, strings_only=True, errors='replace')
if isinstance(params, (list, tuple)):
u_params = tuple(to_string(val) for val in params)
elif params is None:
u_params = ()
else:
u_params = {to_string(k): to_string(v) for k, v in params.items()}
return "QUERY = %r - PARAMS = %r" % (sql, u_params)
def last_insert_id(self, cursor, table_name, pk_name):
"""
Given a cursor object that has just performed an INSERT statement into
a table that has an auto-incrementing ID, return the newly created ID.
`pk_name` is the name of the primary-key column.
"""
return cursor.lastrowid
def lookup_cast(self, lookup_type, internal_type=None):
"""
Return the string to use in a query when performing lookups
("contains", "like", etc.). It should contain a '%s' placeholder for
the column being searched against.
"""
return "%s"
def max_in_list_size(self):
"""
Return the maximum number of items that can be passed in a single 'IN'
list condition, or None if the backend does not impose a limit.
"""
return None
def max_name_length(self):
"""
Return the maximum length of table and column names, or None if there
is no limit.
"""
return None
def no_limit_value(self):
"""
Return the value to use for the LIMIT when we are wanting "LIMIT
infinity". Return None if the limit clause can be omitted in this case.
"""
raise NotImplementedError('subclasses of BaseDatabaseOperations may require a no_limit_value() method')
def pk_default_value(self):
"""
Return the value to use during an INSERT statement to specify that
the field should use its default value.
"""
return 'DEFAULT'
def prepare_sql_script(self, sql):
"""
Take an SQL script that may contain multiple lines and return a list
of statements to feed to successive cursor.execute() calls.
Since few databases are able to process raw SQL scripts in a single
cursor.execute() call and PEP 249 doesn't talk about this use case,
the default implementation is conservative.
"""
return [
sqlparse.format(statement, strip_comments=True)
for statement in sqlparse.split(sql) if statement
]
def process_clob(self, value):
"""
Return the value of a CLOB column, for backends that return a locator
object that requires additional processing.
"""
return value
def return_insert_columns(self, fields):
"""
For backends that support returning columns as part of an insert query,
return the SQL and params to append to the INSERT query. The returned
fragment should contain a format string to hold the appropriate column.
"""
pass
def compiler(self, compiler_name):
"""
Return the SQLCompiler class corresponding to the given name,
in the namespace corresponding to the `compiler_module` attribute
on this backend.
"""
if self._cache is None:
self._cache = import_module(self.compiler_module)
return getattr(self._cache, compiler_name)
def quote_name(self, name):
"""
Return a quoted version of the given table, index, or column name. Do
not quote the given name if it's already been quoted.
"""
raise NotImplementedError('subclasses of BaseDatabaseOperations may require a quote_name() method')
def random_function_sql(self):
"""Return an SQL expression that returns a random value."""
return 'RANDOM()'
def regex_lookup(self, lookup_type):
"""
Return the string to use in a query when performing regular expression
lookups (using "regex" or "iregex"). It should contain a '%s'
placeholder for the column being searched against.
If the feature is not supported (or part of it is not supported), raise
NotImplementedError.
"""
raise NotImplementedError('subclasses of BaseDatabaseOperations may require a regex_lookup() method')
def savepoint_create_sql(self, sid):
"""
Return the SQL for starting a new savepoint. Only required if the
"uses_savepoints" feature is True. The "sid" parameter is a string
for the savepoint id.
"""
return "SAVEPOINT %s" % self.quote_name(sid)
def savepoint_commit_sql(self, sid):
"""
Return the SQL for committing the given savepoint.
"""
return "RELEASE SAVEPOINT %s" % self.quote_name(sid)
def savepoint_rollback_sql(self, sid):
"""
Return the SQL for rolling back the given savepoint.
"""
return "ROLLBACK TO SAVEPOINT %s" % self.quote_name(sid)
def set_time_zone_sql(self):
"""
Return the SQL that will set the connection's time zone.
Return '' if the backend doesn't support time zones.
"""
return ''
def sql_flush(self, style, tables, *, reset_sequences=False, allow_cascade=False):
"""
Return a list of SQL statements required to remove all data from
the given database tables (without actually removing the tables
themselves).
The `style` argument is a Style object as returned by either
color_style() or no_style() in django.core.management.color.
If `reset_sequences` is True, the list includes SQL statements required
to reset the sequences.
The `allow_cascade` argument determines whether truncation may cascade
to tables with foreign keys pointing the tables being truncated.
PostgreSQL requires a cascade even if these tables are empty.
"""
raise NotImplementedError('subclasses of BaseDatabaseOperations must provide an sql_flush() method')
def execute_sql_flush(self, sql_list):
"""Execute a list of SQL statements to flush the database."""
with transaction.atomic(
using=self.connection.alias,
savepoint=self.connection.features.can_rollback_ddl,
):
with self.connection.cursor() as cursor:
for sql in sql_list:
cursor.execute(sql)
def sequence_reset_by_name_sql(self, style, sequences):
"""
Return a list of the SQL statements required to reset sequences
passed in `sequences`.
The `style` argument is a Style object as returned by either
color_style() or no_style() in django.core.management.color.
"""
return []
def sequence_reset_sql(self, style, model_list):
"""
Return a list of the SQL statements required to reset sequences for
the given models.
The `style` argument is a Style object as returned by either
color_style() or no_style() in django.core.management.color.
"""
return [] # No sequence reset required by default.
def start_transaction_sql(self):
"""Return the SQL statement required to start a transaction."""
return "BEGIN;"
def end_transaction_sql(self, success=True):
"""Return the SQL statement required to end a transaction."""
if not success:
return "ROLLBACK;"
return "COMMIT;"
def tablespace_sql(self, tablespace, inline=False):
"""
Return the SQL that will be used in a query to define the tablespace.
Return '' if the backend doesn't support tablespaces.
If `inline` is True, append the SQL to a row; otherwise append it to
the entire CREATE TABLE or CREATE INDEX statement.
"""
return ''
def prep_for_like_query(self, x):
"""Prepare a value for use in a LIKE query."""
return str(x).replace("\\", "\\\\").replace("%", r"\%").replace("_", r"\_")
# Same as prep_for_like_query(), but called for "iexact" matches, which
# need not necessarily be implemented using "LIKE" in the backend.
prep_for_iexact_query = prep_for_like_query
def validate_autopk_value(self, value):
"""
Certain backends do not accept some values for "serial" fields
(for example zero in MySQL). Raise a ValueError if the value is
invalid, otherwise return the validated value.
"""
return value
def adapt_unknown_value(self, value):
"""
Transform a value to something compatible with the backend driver.
This method only depends on the type of the value. It's designed for
cases where the target type isn't known, such as .raw() SQL queries.
As a consequence it may not work perfectly in all circumstances.
"""
if isinstance(value, datetime.datetime): # must be before date
return self.adapt_datetimefield_value(value)
elif isinstance(value, datetime.date):
return self.adapt_datefield_value(value)
elif isinstance(value, datetime.time):
return self.adapt_timefield_value(value)
elif isinstance(value, decimal.Decimal):
return self.adapt_decimalfield_value(value)
else:
return value
def adapt_datefield_value(self, value):
"""
Transform a date value to an object compatible with what is expected
by the backend driver for date columns.
"""
if value is None:
return None
return str(value)
def adapt_datetimefield_value(self, value):
"""
Transform a datetime value to an object compatible with what is expected
by the backend driver for datetime columns.
"""
if value is None:
return None
return str(value)
def adapt_timefield_value(self, value):
"""
Transform a time value to an object compatible with what is expected
by the backend driver for time columns.
"""
if value is None:
return None
if timezone.is_aware(value):
raise ValueError("Django does not support timezone-aware times.")
return str(value)
def adapt_decimalfield_value(self, value, max_digits=None, decimal_places=None):
"""
Transform a decimal.Decimal value to an object compatible with what is
expected by the backend driver for decimal (numeric) columns.
"""
return utils.format_number(value, max_digits, decimal_places)
def adapt_ipaddressfield_value(self, value):
"""
Transform a string representation of an IP address into the expected
type for the backend driver.
"""
return value or None
def year_lookup_bounds_for_date_field(self, value):
"""
Return a two-elements list with the lower and upper bound to be used
with a BETWEEN operator to query a DateField value using a year
lookup.
`value` is an int, containing the looked-up year.
"""
first = datetime.date(value, 1, 1)
second = datetime.date(value, 12, 31)
first = self.adapt_datefield_value(first)
second = self.adapt_datefield_value(second)
return [first, second]
def year_lookup_bounds_for_datetime_field(self, value):
"""
Return a two-elements list with the lower and upper bound to be used
with a BETWEEN operator to query a DateTimeField value using a year
lookup.
`value` is an int, containing the looked-up year.
"""
first = datetime.datetime(value, 1, 1)
second = datetime.datetime(value, 12, 31, 23, 59, 59, 999999)
if settings.USE_TZ:
tz = timezone.get_current_timezone()
first = timezone.make_aware(first, tz)
second = timezone.make_aware(second, tz)
first = self.adapt_datetimefield_value(first)
second = self.adapt_datetimefield_value(second)
return [first, second]
def get_db_converters(self, expression):
"""
Return a list of functions needed to convert field data.
Some field types on some backends do not provide data in the correct
format, this is the hook for converter functions.
"""
return []
def convert_durationfield_value(self, value, expression, connection):
if value is not None:
return datetime.timedelta(0, 0, value)
def check_expression_support(self, expression):
"""
Check that the backend supports the provided expression.
This is used on specific backends to rule out known expressions
that have problematic or nonexistent implementations. If the
expression has a known problem, the backend should raise
NotSupportedError.
"""
pass
def conditional_expression_supported_in_where_clause(self, expression):
"""
Return True, if the conditional expression is supported in the WHERE
clause.
"""
return True
def combine_expression(self, connector, sub_expressions):
"""
Combine a list of subexpressions into a single expression, using
the provided connecting operator. This is required because operators
can vary between backends (e.g., Oracle with %% and &) and between
subexpression types (e.g., date expressions).
"""
conn = ' %s ' % connector
return conn.join(sub_expressions)
def combine_duration_expression(self, connector, sub_expressions):
return self.combine_expression(connector, sub_expressions)
def binary_placeholder_sql(self, value):
"""
Some backends require special syntax to insert binary content (MySQL
for example uses '_binary %s').
"""
return '%s'
def modify_insert_params(self, placeholder, params):
"""
Allow modification of insert parameters. Needed for Oracle Spatial
backend due to #10888.
"""
return params
def integer_field_range(self, internal_type):
"""
Given an integer field internal type (e.g. 'PositiveIntegerField'),
return a tuple of the (min_value, max_value) form representing the
range of the column type bound to the field.
"""
return self.integer_field_ranges[internal_type]
def subtract_temporals(self, internal_type, lhs, rhs):
if self.connection.features.supports_temporal_subtraction:
lhs_sql, lhs_params = lhs
rhs_sql, rhs_params = rhs
return '(%s - %s)' % (lhs_sql, rhs_sql), (*lhs_params, *rhs_params)
raise NotSupportedError("This backend does not support %s subtraction." % internal_type)
def window_frame_start(self, start):
if isinstance(start, int):
if start < 0:
return '%d %s' % (abs(start), self.PRECEDING)
elif start == 0:
return self.CURRENT_ROW
elif start is None:
return self.UNBOUNDED_PRECEDING
raise ValueError("start argument must be a negative integer, zero, or None, but got '%s'." % start)
def window_frame_end(self, end):
if isinstance(end, int):
if end == 0:
return self.CURRENT_ROW
elif end > 0:
return '%d %s' % (end, self.FOLLOWING)
elif end is None:
return self.UNBOUNDED_FOLLOWING
raise ValueError("end argument must be a positive integer, zero, or None, but got '%s'." % end)
def window_frame_rows_start_end(self, start=None, end=None):
"""
Return SQL for start and end points in an OVER clause window frame.
"""
if not self.connection.features.supports_over_clause:
raise NotSupportedError('This backend does not support window expressions.')
return self.window_frame_start(start), self.window_frame_end(end)
def window_frame_range_start_end(self, start=None, end=None):
start_, end_ = self.window_frame_rows_start_end(start, end)
if (
self.connection.features.only_supports_unbounded_with_preceding_and_following and
((start and start < 0) or (end and end > 0))
):
raise NotSupportedError(
'%s only supports UNBOUNDED together with PRECEDING and '
'FOLLOWING.' % self.connection.display_name
)
return start_, end_
def explain_query_prefix(self, format=None, **options):
if not self.connection.features.supports_explaining_query_execution:
raise NotSupportedError('This backend does not support explaining query execution.')
if format:
supported_formats = self.connection.features.supported_explain_formats
normalized_format = format.upper()
if normalized_format not in supported_formats:
msg = '%s is not a recognized format.' % normalized_format
if supported_formats:
msg += ' Allowed formats: %s' % ', '.join(sorted(supported_formats))
raise ValueError(msg)
if options:
raise ValueError('Unknown options: %s' % ', '.join(sorted(options.keys())))
return self.explain_prefix
def insert_statement(self, ignore_conflicts=False):
return 'INSERT INTO'
def ignore_conflicts_suffix_sql(self, ignore_conflicts=None):
return ''
|
08b66978aefb5d826f2b3e44d71f2919c3ff4b710dc7092e1546c06fc5d5f4b9 | import logging
from datetime import datetime
from django.db.backends.ddl_references import (
Columns, ForeignKeyName, IndexName, Statement, Table,
)
from django.db.backends.utils import names_digest, split_identifier
from django.db.models import Deferrable, Index
from django.db.transaction import TransactionManagementError, atomic
from django.utils import timezone
logger = logging.getLogger('django.db.backends.schema')
def _is_relevant_relation(relation, altered_field):
"""
When altering the given field, must constraints on its model from the given
relation be temporarily dropped?
"""
field = relation.field
if field.many_to_many:
# M2M reverse field
return False
if altered_field.primary_key and field.to_fields == [None]:
# Foreign key constraint on the primary key, which is being altered.
return True
# Is the constraint targeting the field being altered?
return altered_field.name in field.to_fields
def _all_related_fields(model):
return model._meta._get_fields(forward=False, reverse=True, include_hidden=True)
def _related_non_m2m_objects(old_field, new_field):
# Filter out m2m objects from reverse relations.
# Return (old_relation, new_relation) tuples.
return zip(
(obj for obj in _all_related_fields(old_field.model) if _is_relevant_relation(obj, old_field)),
(obj for obj in _all_related_fields(new_field.model) if _is_relevant_relation(obj, new_field)),
)
class BaseDatabaseSchemaEditor:
"""
This class and its subclasses are responsible for emitting schema-changing
statements to the databases - model creation/removal/alteration, field
renaming, index fiddling, and so on.
"""
# Overrideable SQL templates
sql_create_table = "CREATE TABLE %(table)s (%(definition)s)"
sql_rename_table = "ALTER TABLE %(old_table)s RENAME TO %(new_table)s"
sql_retablespace_table = "ALTER TABLE %(table)s SET TABLESPACE %(new_tablespace)s"
sql_delete_table = "DROP TABLE %(table)s CASCADE"
sql_create_column = "ALTER TABLE %(table)s ADD COLUMN %(column)s %(definition)s"
sql_alter_column = "ALTER TABLE %(table)s %(changes)s"
sql_alter_column_type = "ALTER COLUMN %(column)s TYPE %(type)s"
sql_alter_column_null = "ALTER COLUMN %(column)s DROP NOT NULL"
sql_alter_column_not_null = "ALTER COLUMN %(column)s SET NOT NULL"
sql_alter_column_default = "ALTER COLUMN %(column)s SET DEFAULT %(default)s"
sql_alter_column_no_default = "ALTER COLUMN %(column)s DROP DEFAULT"
sql_delete_column = "ALTER TABLE %(table)s DROP COLUMN %(column)s CASCADE"
sql_rename_column = "ALTER TABLE %(table)s RENAME COLUMN %(old_column)s TO %(new_column)s"
sql_update_with_default = "UPDATE %(table)s SET %(column)s = %(default)s WHERE %(column)s IS NULL"
sql_unique_constraint = "UNIQUE (%(columns)s)%(deferrable)s"
sql_check_constraint = "CHECK (%(check)s)"
sql_delete_constraint = "ALTER TABLE %(table)s DROP CONSTRAINT %(name)s"
sql_constraint = "CONSTRAINT %(name)s %(constraint)s"
sql_create_check = "ALTER TABLE %(table)s ADD CONSTRAINT %(name)s CHECK (%(check)s)"
sql_delete_check = sql_delete_constraint
sql_create_unique = "ALTER TABLE %(table)s ADD CONSTRAINT %(name)s UNIQUE (%(columns)s)%(deferrable)s"
sql_delete_unique = sql_delete_constraint
sql_create_fk = (
"ALTER TABLE %(table)s ADD CONSTRAINT %(name)s FOREIGN KEY (%(column)s) "
"REFERENCES %(to_table)s (%(to_column)s)%(deferrable)s"
)
sql_create_inline_fk = None
sql_create_column_inline_fk = None
sql_delete_fk = sql_delete_constraint
sql_create_index = "CREATE INDEX %(name)s ON %(table)s (%(columns)s)%(extra)s%(condition)s"
sql_create_unique_index = "CREATE UNIQUE INDEX %(name)s ON %(table)s (%(columns)s)%(condition)s"
sql_delete_index = "DROP INDEX %(name)s"
sql_create_pk = "ALTER TABLE %(table)s ADD CONSTRAINT %(name)s PRIMARY KEY (%(columns)s)"
sql_delete_pk = sql_delete_constraint
sql_delete_procedure = 'DROP PROCEDURE %(procedure)s'
def __init__(self, connection, collect_sql=False, atomic=True):
self.connection = connection
self.collect_sql = collect_sql
if self.collect_sql:
self.collected_sql = []
self.atomic_migration = self.connection.features.can_rollback_ddl and atomic
# State-managing methods
def __enter__(self):
self.deferred_sql = []
if self.atomic_migration:
self.atomic = atomic(self.connection.alias)
self.atomic.__enter__()
return self
def __exit__(self, exc_type, exc_value, traceback):
if exc_type is None:
for sql in self.deferred_sql:
self.execute(sql)
if self.atomic_migration:
self.atomic.__exit__(exc_type, exc_value, traceback)
# Core utility functions
def execute(self, sql, params=()):
"""Execute the given SQL statement, with optional parameters."""
# Don't perform the transactional DDL check if SQL is being collected
# as it's not going to be executed anyway.
if not self.collect_sql and self.connection.in_atomic_block and not self.connection.features.can_rollback_ddl:
raise TransactionManagementError(
"Executing DDL statements while in a transaction on databases "
"that can't perform a rollback is prohibited."
)
# Account for non-string statement objects.
sql = str(sql)
# Log the command we're running, then run it
logger.debug("%s; (params %r)", sql, params, extra={'params': params, 'sql': sql})
if self.collect_sql:
ending = "" if sql.endswith(";") else ";"
if params is not None:
self.collected_sql.append((sql % tuple(map(self.quote_value, params))) + ending)
else:
self.collected_sql.append(sql + ending)
else:
with self.connection.cursor() as cursor:
cursor.execute(sql, params)
def quote_name(self, name):
return self.connection.ops.quote_name(name)
def table_sql(self, model):
"""Take a model and return its table definition."""
# Add any unique_togethers (always deferred, as some fields might be
# created afterwards, like geometry fields with some backends).
for fields in model._meta.unique_together:
columns = [model._meta.get_field(field).column for field in fields]
self.deferred_sql.append(self._create_unique_sql(model, columns))
# Create column SQL, add FK deferreds if needed.
column_sqls = []
params = []
for field in model._meta.local_fields:
# SQL.
definition, extra_params = self.column_sql(model, field)
if definition is None:
continue
# Check constraints can go on the column SQL here.
db_params = field.db_parameters(connection=self.connection)
if db_params['check']:
definition += ' ' + self.sql_check_constraint % db_params
# Autoincrement SQL (for backends with inline variant).
col_type_suffix = field.db_type_suffix(connection=self.connection)
if col_type_suffix:
definition += ' %s' % col_type_suffix
params.extend(extra_params)
# FK.
if field.remote_field and field.db_constraint:
to_table = field.remote_field.model._meta.db_table
to_column = field.remote_field.model._meta.get_field(field.remote_field.field_name).column
if self.sql_create_inline_fk:
definition += ' ' + self.sql_create_inline_fk % {
'to_table': self.quote_name(to_table),
'to_column': self.quote_name(to_column),
}
elif self.connection.features.supports_foreign_keys:
self.deferred_sql.append(self._create_fk_sql(model, field, '_fk_%(to_table)s_%(to_column)s'))
# Add the SQL to our big list.
column_sqls.append('%s %s' % (
self.quote_name(field.column),
definition,
))
# Autoincrement SQL (for backends with post table definition
# variant).
if field.get_internal_type() in ('AutoField', 'BigAutoField', 'SmallAutoField'):
autoinc_sql = self.connection.ops.autoinc_sql(model._meta.db_table, field.column)
if autoinc_sql:
self.deferred_sql.extend(autoinc_sql)
constraints = [constraint.constraint_sql(model, self) for constraint in model._meta.constraints]
sql = self.sql_create_table % {
'table': self.quote_name(model._meta.db_table),
'definition': ', '.join(constraint for constraint in (*column_sqls, *constraints) if constraint),
}
if model._meta.db_tablespace:
tablespace_sql = self.connection.ops.tablespace_sql(model._meta.db_tablespace)
if tablespace_sql:
sql += ' ' + tablespace_sql
return sql, params
# Field <-> database mapping functions
def column_sql(self, model, field, include_default=False):
"""
Take a field and return its column definition.
The field must already have had set_attributes_from_name() called.
"""
# Get the column's type and use that as the basis of the SQL
db_params = field.db_parameters(connection=self.connection)
sql = db_params['type']
params = []
# Check for fields that aren't actually columns (e.g. M2M)
if sql is None:
return None, None
# Work out nullability
null = field.null
# If we were told to include a default value, do so
include_default = include_default and not self.skip_default(field)
if include_default:
default_value = self.effective_default(field)
column_default = ' DEFAULT ' + self._column_default_sql(field)
if default_value is not None:
if self.connection.features.requires_literal_defaults:
# Some databases can't take defaults as a parameter (oracle)
# If this is the case, the individual schema backend should
# implement prepare_default
sql += column_default % self.prepare_default(default_value)
else:
sql += column_default
params += [default_value]
# Oracle treats the empty string ('') as null, so coerce the null
# option whenever '' is a possible value.
if (field.empty_strings_allowed and not field.primary_key and
self.connection.features.interprets_empty_strings_as_nulls):
null = True
if null and not self.connection.features.implied_column_null:
sql += " NULL"
elif not null:
sql += " NOT NULL"
# Primary key/unique outputs
if field.primary_key:
sql += " PRIMARY KEY"
elif field.unique:
sql += " UNIQUE"
# Optionally add the tablespace if it's an implicitly indexed column
tablespace = field.db_tablespace or model._meta.db_tablespace
if tablespace and self.connection.features.supports_tablespaces and field.unique:
sql += " %s" % self.connection.ops.tablespace_sql(tablespace, inline=True)
# Return the sql
return sql, params
def skip_default(self, field):
"""
Some backends don't accept default values for certain columns types
(i.e. MySQL longtext and longblob).
"""
return False
def prepare_default(self, value):
"""
Only used for backends which have requires_literal_defaults feature
"""
raise NotImplementedError(
'subclasses of BaseDatabaseSchemaEditor for backends which have '
'requires_literal_defaults must provide a prepare_default() method'
)
def _column_default_sql(self, field):
"""
Return the SQL to use in a DEFAULT clause. The resulting string should
contain a '%s' placeholder for a default value.
"""
return '%s'
@staticmethod
def _effective_default(field):
# This method allows testing its logic without a connection.
if field.has_default():
default = field.get_default()
elif not field.null and field.blank and field.empty_strings_allowed:
if field.get_internal_type() == "BinaryField":
default = b''
else:
default = ''
elif getattr(field, 'auto_now', False) or getattr(field, 'auto_now_add', False):
default = datetime.now()
internal_type = field.get_internal_type()
if internal_type == 'DateField':
default = default.date()
elif internal_type == 'TimeField':
default = default.time()
elif internal_type == 'DateTimeField':
default = timezone.now()
else:
default = None
return default
def effective_default(self, field):
"""Return a field's effective database default value."""
return field.get_db_prep_save(self._effective_default(field), self.connection)
def quote_value(self, value):
"""
Return a quoted version of the value so it's safe to use in an SQL
string. This is not safe against injection from user code; it is
intended only for use in making SQL scripts or preparing default values
for particularly tricky backends (defaults are not user-defined, though,
so this is safe).
"""
raise NotImplementedError()
# Actions
def create_model(self, model):
"""
Create a table and any accompanying indexes or unique constraints for
the given `model`.
"""
sql, params = self.table_sql(model)
# Prevent using [] as params, in the case a literal '%' is used in the definition
self.execute(sql, params or None)
# Add any field index and index_together's (deferred as SQLite _remake_table needs it)
self.deferred_sql.extend(self._model_indexes_sql(model))
# Make M2M tables
for field in model._meta.local_many_to_many:
if field.remote_field.through._meta.auto_created:
self.create_model(field.remote_field.through)
def delete_model(self, model):
"""Delete a model from the database."""
# Handle auto-created intermediary models
for field in model._meta.local_many_to_many:
if field.remote_field.through._meta.auto_created:
self.delete_model(field.remote_field.through)
# Delete the table
self.execute(self.sql_delete_table % {
"table": self.quote_name(model._meta.db_table),
})
# Remove all deferred statements referencing the deleted table.
for sql in list(self.deferred_sql):
if isinstance(sql, Statement) and sql.references_table(model._meta.db_table):
self.deferred_sql.remove(sql)
def add_index(self, model, index):
"""Add an index on a model."""
self.execute(index.create_sql(model, self), params=None)
def remove_index(self, model, index):
"""Remove an index from a model."""
self.execute(index.remove_sql(model, self))
def add_constraint(self, model, constraint):
"""Add a constraint to a model."""
sql = constraint.create_sql(model, self)
if sql:
self.execute(sql)
def remove_constraint(self, model, constraint):
"""Remove a constraint from a model."""
sql = constraint.remove_sql(model, self)
if sql:
self.execute(sql)
def alter_unique_together(self, model, old_unique_together, new_unique_together):
"""
Deal with a model changing its unique_together. The input
unique_togethers must be doubly-nested, not the single-nested
["foo", "bar"] format.
"""
olds = {tuple(fields) for fields in old_unique_together}
news = {tuple(fields) for fields in new_unique_together}
# Deleted uniques
for fields in olds.difference(news):
self._delete_composed_index(model, fields, {'unique': True}, self.sql_delete_unique)
# Created uniques
for fields in news.difference(olds):
columns = [model._meta.get_field(field).column for field in fields]
self.execute(self._create_unique_sql(model, columns))
def alter_index_together(self, model, old_index_together, new_index_together):
"""
Deal with a model changing its index_together. The input
index_togethers must be doubly-nested, not the single-nested
["foo", "bar"] format.
"""
olds = {tuple(fields) for fields in old_index_together}
news = {tuple(fields) for fields in new_index_together}
# Deleted indexes
for fields in olds.difference(news):
self._delete_composed_index(
model,
fields,
{'index': True, 'unique': False},
self.sql_delete_index,
)
# Created indexes
for field_names in news.difference(olds):
fields = [model._meta.get_field(field) for field in field_names]
self.execute(self._create_index_sql(model, fields, suffix="_idx"))
def _delete_composed_index(self, model, fields, constraint_kwargs, sql):
meta_constraint_names = {constraint.name for constraint in model._meta.constraints}
meta_index_names = {constraint.name for constraint in model._meta.indexes}
columns = [model._meta.get_field(field).column for field in fields]
constraint_names = self._constraint_names(
model, columns, exclude=meta_constraint_names | meta_index_names,
**constraint_kwargs
)
if len(constraint_names) != 1:
raise ValueError("Found wrong number (%s) of constraints for %s(%s)" % (
len(constraint_names),
model._meta.db_table,
", ".join(columns),
))
self.execute(self._delete_constraint_sql(sql, model, constraint_names[0]))
def alter_db_table(self, model, old_db_table, new_db_table):
"""Rename the table a model points to."""
if (old_db_table == new_db_table or
(self.connection.features.ignores_table_name_case and
old_db_table.lower() == new_db_table.lower())):
return
self.execute(self.sql_rename_table % {
"old_table": self.quote_name(old_db_table),
"new_table": self.quote_name(new_db_table),
})
# Rename all references to the old table name.
for sql in self.deferred_sql:
if isinstance(sql, Statement):
sql.rename_table_references(old_db_table, new_db_table)
def alter_db_tablespace(self, model, old_db_tablespace, new_db_tablespace):
"""Move a model's table between tablespaces."""
self.execute(self.sql_retablespace_table % {
"table": self.quote_name(model._meta.db_table),
"old_tablespace": self.quote_name(old_db_tablespace),
"new_tablespace": self.quote_name(new_db_tablespace),
})
def add_field(self, model, field):
"""
Create a field on a model. Usually involves adding a column, but may
involve adding a table instead (for M2M fields).
"""
# Special-case implicit M2M tables
if field.many_to_many and field.remote_field.through._meta.auto_created:
return self.create_model(field.remote_field.through)
# Get the column's definition
definition, params = self.column_sql(model, field, include_default=True)
# It might not actually have a column behind it
if definition is None:
return
# Check constraints can go on the column SQL here
db_params = field.db_parameters(connection=self.connection)
if db_params['check']:
definition += " " + self.sql_check_constraint % db_params
if field.remote_field and self.connection.features.supports_foreign_keys and field.db_constraint:
constraint_suffix = '_fk_%(to_table)s_%(to_column)s'
# Add FK constraint inline, if supported.
if self.sql_create_column_inline_fk:
to_table = field.remote_field.model._meta.db_table
to_column = field.remote_field.model._meta.get_field(field.remote_field.field_name).column
definition += " " + self.sql_create_column_inline_fk % {
'name': self._fk_constraint_name(model, field, constraint_suffix),
'column': self.quote_name(field.column),
'to_table': self.quote_name(to_table),
'to_column': self.quote_name(to_column),
'deferrable': self.connection.ops.deferrable_sql()
}
# Otherwise, add FK constraints later.
else:
self.deferred_sql.append(self._create_fk_sql(model, field, constraint_suffix))
# Build the SQL and run it
sql = self.sql_create_column % {
"table": self.quote_name(model._meta.db_table),
"column": self.quote_name(field.column),
"definition": definition,
}
self.execute(sql, params)
# Drop the default if we need to
# (Django usually does not use in-database defaults)
if not self.skip_default(field) and self.effective_default(field) is not None:
changes_sql, params = self._alter_column_default_sql(model, None, field, drop=True)
sql = self.sql_alter_column % {
"table": self.quote_name(model._meta.db_table),
"changes": changes_sql,
}
self.execute(sql, params)
# Add an index, if required
self.deferred_sql.extend(self._field_indexes_sql(model, field))
# Reset connection if required
if self.connection.features.connection_persists_old_columns:
self.connection.close()
def remove_field(self, model, field):
"""
Remove a field from a model. Usually involves deleting a column,
but for M2Ms may involve deleting a table.
"""
# Special-case implicit M2M tables
if field.many_to_many and field.remote_field.through._meta.auto_created:
return self.delete_model(field.remote_field.through)
# It might not actually have a column behind it
if field.db_parameters(connection=self.connection)['type'] is None:
return
# Drop any FK constraints, MySQL requires explicit deletion
if field.remote_field:
fk_names = self._constraint_names(model, [field.column], foreign_key=True)
for fk_name in fk_names:
self.execute(self._delete_fk_sql(model, fk_name))
# Delete the column
sql = self.sql_delete_column % {
"table": self.quote_name(model._meta.db_table),
"column": self.quote_name(field.column),
}
self.execute(sql)
# Reset connection if required
if self.connection.features.connection_persists_old_columns:
self.connection.close()
# Remove all deferred statements referencing the deleted column.
for sql in list(self.deferred_sql):
if isinstance(sql, Statement) and sql.references_column(model._meta.db_table, field.column):
self.deferred_sql.remove(sql)
def alter_field(self, model, old_field, new_field, strict=False):
"""
Allow a field's type, uniqueness, nullability, default, column,
constraints, etc. to be modified.
`old_field` is required to compute the necessary changes.
If `strict` is True, raise errors if the old column does not match
`old_field` precisely.
"""
# Ensure this field is even column-based
old_db_params = old_field.db_parameters(connection=self.connection)
old_type = old_db_params['type']
new_db_params = new_field.db_parameters(connection=self.connection)
new_type = new_db_params['type']
if ((old_type is None and old_field.remote_field is None) or
(new_type is None and new_field.remote_field is None)):
raise ValueError(
"Cannot alter field %s into %s - they do not properly define "
"db_type (are you using a badly-written custom field?)" %
(old_field, new_field),
)
elif old_type is None and new_type is None and (
old_field.remote_field.through and new_field.remote_field.through and
old_field.remote_field.through._meta.auto_created and
new_field.remote_field.through._meta.auto_created):
return self._alter_many_to_many(model, old_field, new_field, strict)
elif old_type is None and new_type is None and (
old_field.remote_field.through and new_field.remote_field.through and
not old_field.remote_field.through._meta.auto_created and
not new_field.remote_field.through._meta.auto_created):
# Both sides have through models; this is a no-op.
return
elif old_type is None or new_type is None:
raise ValueError(
"Cannot alter field %s into %s - they are not compatible types "
"(you cannot alter to or from M2M fields, or add or remove "
"through= on M2M fields)" % (old_field, new_field)
)
self._alter_field(model, old_field, new_field, old_type, new_type,
old_db_params, new_db_params, strict)
def _alter_field(self, model, old_field, new_field, old_type, new_type,
old_db_params, new_db_params, strict=False):
"""Perform a "physical" (non-ManyToMany) field update."""
# Drop any FK constraints, we'll remake them later
fks_dropped = set()
if (
self.connection.features.supports_foreign_keys and
old_field.remote_field and
old_field.db_constraint
):
fk_names = self._constraint_names(model, [old_field.column], foreign_key=True)
if strict and len(fk_names) != 1:
raise ValueError("Found wrong number (%s) of foreign key constraints for %s.%s" % (
len(fk_names),
model._meta.db_table,
old_field.column,
))
for fk_name in fk_names:
fks_dropped.add((old_field.column,))
self.execute(self._delete_fk_sql(model, fk_name))
# Has unique been removed?
if old_field.unique and (not new_field.unique or self._field_became_primary_key(old_field, new_field)):
# Find the unique constraint for this field
meta_constraint_names = {constraint.name for constraint in model._meta.constraints}
constraint_names = self._constraint_names(
model, [old_field.column], unique=True, primary_key=False,
exclude=meta_constraint_names,
)
if strict and len(constraint_names) != 1:
raise ValueError("Found wrong number (%s) of unique constraints for %s.%s" % (
len(constraint_names),
model._meta.db_table,
old_field.column,
))
for constraint_name in constraint_names:
self.execute(self._delete_unique_sql(model, constraint_name))
# Drop incoming FK constraints if the field is a primary key or unique,
# which might be a to_field target, and things are going to change.
drop_foreign_keys = (
self.connection.features.supports_foreign_keys and (
(old_field.primary_key and new_field.primary_key) or
(old_field.unique and new_field.unique)
) and old_type != new_type
)
if drop_foreign_keys:
# '_meta.related_field' also contains M2M reverse fields, these
# will be filtered out
for _old_rel, new_rel in _related_non_m2m_objects(old_field, new_field):
rel_fk_names = self._constraint_names(
new_rel.related_model, [new_rel.field.column], foreign_key=True
)
for fk_name in rel_fk_names:
self.execute(self._delete_fk_sql(new_rel.related_model, fk_name))
# Removed an index? (no strict check, as multiple indexes are possible)
# Remove indexes if db_index switched to False or a unique constraint
# will now be used in lieu of an index. The following lines from the
# truth table show all True cases; the rest are False:
#
# old_field.db_index | old_field.unique | new_field.db_index | new_field.unique
# ------------------------------------------------------------------------------
# True | False | False | False
# True | False | False | True
# True | False | True | True
if old_field.db_index and not old_field.unique and (not new_field.db_index or new_field.unique):
# Find the index for this field
meta_index_names = {index.name for index in model._meta.indexes}
# Retrieve only BTREE indexes since this is what's created with
# db_index=True.
index_names = self._constraint_names(
model, [old_field.column], index=True, type_=Index.suffix,
exclude=meta_index_names,
)
for index_name in index_names:
# The only way to check if an index was created with
# db_index=True or with Index(['field'], name='foo')
# is to look at its name (refs #28053).
self.execute(self._delete_index_sql(model, index_name))
# Change check constraints?
if old_db_params['check'] != new_db_params['check'] and old_db_params['check']:
meta_constraint_names = {constraint.name for constraint in model._meta.constraints}
constraint_names = self._constraint_names(
model, [old_field.column], check=True,
exclude=meta_constraint_names,
)
if strict and len(constraint_names) != 1:
raise ValueError("Found wrong number (%s) of check constraints for %s.%s" % (
len(constraint_names),
model._meta.db_table,
old_field.column,
))
for constraint_name in constraint_names:
self.execute(self._delete_check_sql(model, constraint_name))
# Have they renamed the column?
if old_field.column != new_field.column:
self.execute(self._rename_field_sql(model._meta.db_table, old_field, new_field, new_type))
# Rename all references to the renamed column.
for sql in self.deferred_sql:
if isinstance(sql, Statement):
sql.rename_column_references(model._meta.db_table, old_field.column, new_field.column)
# Next, start accumulating actions to do
actions = []
null_actions = []
post_actions = []
# Type change?
if old_type != new_type:
fragment, other_actions = self._alter_column_type_sql(model, old_field, new_field, new_type)
actions.append(fragment)
post_actions.extend(other_actions)
# When changing a column NULL constraint to NOT NULL with a given
# default value, we need to perform 4 steps:
# 1. Add a default for new incoming writes
# 2. Update existing NULL rows with new default
# 3. Replace NULL constraint with NOT NULL
# 4. Drop the default again.
# Default change?
needs_database_default = False
if old_field.null and not new_field.null:
old_default = self.effective_default(old_field)
new_default = self.effective_default(new_field)
if (
not self.skip_default(new_field) and
old_default != new_default and
new_default is not None
):
needs_database_default = True
actions.append(self._alter_column_default_sql(model, old_field, new_field))
# Nullability change?
if old_field.null != new_field.null:
fragment = self._alter_column_null_sql(model, old_field, new_field)
if fragment:
null_actions.append(fragment)
# Only if we have a default and there is a change from NULL to NOT NULL
four_way_default_alteration = (
new_field.has_default() and
(old_field.null and not new_field.null)
)
if actions or null_actions:
if not four_way_default_alteration:
# If we don't have to do a 4-way default alteration we can
# directly run a (NOT) NULL alteration
actions = actions + null_actions
# Combine actions together if we can (e.g. postgres)
if self.connection.features.supports_combined_alters and actions:
sql, params = tuple(zip(*actions))
actions = [(", ".join(sql), sum(params, []))]
# Apply those actions
for sql, params in actions:
self.execute(
self.sql_alter_column % {
"table": self.quote_name(model._meta.db_table),
"changes": sql,
},
params,
)
if four_way_default_alteration:
# Update existing rows with default value
self.execute(
self.sql_update_with_default % {
"table": self.quote_name(model._meta.db_table),
"column": self.quote_name(new_field.column),
"default": "%s",
},
[new_default],
)
# Since we didn't run a NOT NULL change before we need to do it
# now
for sql, params in null_actions:
self.execute(
self.sql_alter_column % {
"table": self.quote_name(model._meta.db_table),
"changes": sql,
},
params,
)
if post_actions:
for sql, params in post_actions:
self.execute(sql, params)
# If primary_key changed to False, delete the primary key constraint.
if old_field.primary_key and not new_field.primary_key:
self._delete_primary_key(model, strict)
# Added a unique?
if self._unique_should_be_added(old_field, new_field):
self.execute(self._create_unique_sql(model, [new_field.column]))
# Added an index? Add an index if db_index switched to True or a unique
# constraint will no longer be used in lieu of an index. The following
# lines from the truth table show all True cases; the rest are False:
#
# old_field.db_index | old_field.unique | new_field.db_index | new_field.unique
# ------------------------------------------------------------------------------
# False | False | True | False
# False | True | True | False
# True | True | True | False
if (not old_field.db_index or old_field.unique) and new_field.db_index and not new_field.unique:
self.execute(self._create_index_sql(model, [new_field]))
# Type alteration on primary key? Then we need to alter the column
# referring to us.
rels_to_update = []
if drop_foreign_keys:
rels_to_update.extend(_related_non_m2m_objects(old_field, new_field))
# Changed to become primary key?
if self._field_became_primary_key(old_field, new_field):
# Make the new one
self.execute(self._create_primary_key_sql(model, new_field))
# Update all referencing columns
rels_to_update.extend(_related_non_m2m_objects(old_field, new_field))
# Handle our type alters on the other end of rels from the PK stuff above
for old_rel, new_rel in rels_to_update:
rel_db_params = new_rel.field.db_parameters(connection=self.connection)
rel_type = rel_db_params['type']
fragment, other_actions = self._alter_column_type_sql(
new_rel.related_model, old_rel.field, new_rel.field, rel_type
)
self.execute(
self.sql_alter_column % {
"table": self.quote_name(new_rel.related_model._meta.db_table),
"changes": fragment[0],
},
fragment[1],
)
for sql, params in other_actions:
self.execute(sql, params)
# Does it have a foreign key?
if (self.connection.features.supports_foreign_keys and new_field.remote_field and
(fks_dropped or not old_field.remote_field or not old_field.db_constraint) and
new_field.db_constraint):
self.execute(self._create_fk_sql(model, new_field, "_fk_%(to_table)s_%(to_column)s"))
# Rebuild FKs that pointed to us if we previously had to drop them
if drop_foreign_keys:
for rel in new_field.model._meta.related_objects:
if _is_relevant_relation(rel, new_field) and rel.field.db_constraint:
self.execute(self._create_fk_sql(rel.related_model, rel.field, "_fk"))
# Does it have check constraints we need to add?
if old_db_params['check'] != new_db_params['check'] and new_db_params['check']:
constraint_name = self._create_index_name(model._meta.db_table, [new_field.column], suffix='_check')
self.execute(self._create_check_sql(model, constraint_name, new_db_params['check']))
# Drop the default if we need to
# (Django usually does not use in-database defaults)
if needs_database_default:
changes_sql, params = self._alter_column_default_sql(model, old_field, new_field, drop=True)
sql = self.sql_alter_column % {
"table": self.quote_name(model._meta.db_table),
"changes": changes_sql,
}
self.execute(sql, params)
# Reset connection if required
if self.connection.features.connection_persists_old_columns:
self.connection.close()
def _alter_column_null_sql(self, model, old_field, new_field):
"""
Hook to specialize column null alteration.
Return a (sql, params) fragment to set a column to null or non-null
as required by new_field, or None if no changes are required.
"""
if (self.connection.features.interprets_empty_strings_as_nulls and
new_field.get_internal_type() in ("CharField", "TextField")):
# The field is nullable in the database anyway, leave it alone.
return
else:
new_db_params = new_field.db_parameters(connection=self.connection)
sql = self.sql_alter_column_null if new_field.null else self.sql_alter_column_not_null
return (
sql % {
'column': self.quote_name(new_field.column),
'type': new_db_params['type'],
},
[],
)
def _alter_column_default_sql(self, model, old_field, new_field, drop=False):
"""
Hook to specialize column default alteration.
Return a (sql, params) fragment to add or drop (depending on the drop
argument) a default to new_field's column.
"""
new_default = self.effective_default(new_field)
default = self._column_default_sql(new_field)
params = [new_default]
if drop:
params = []
elif self.connection.features.requires_literal_defaults:
# Some databases (Oracle) can't take defaults as a parameter
# If this is the case, the SchemaEditor for that database should
# implement prepare_default().
default = self.prepare_default(new_default)
params = []
new_db_params = new_field.db_parameters(connection=self.connection)
sql = self.sql_alter_column_no_default if drop else self.sql_alter_column_default
return (
sql % {
'column': self.quote_name(new_field.column),
'type': new_db_params['type'],
'default': default,
},
params,
)
def _alter_column_type_sql(self, model, old_field, new_field, new_type):
"""
Hook to specialize column type alteration for different backends,
for cases when a creation type is different to an alteration type
(e.g. SERIAL in PostgreSQL, PostGIS fields).
Return a two-tuple of: an SQL fragment of (sql, params) to insert into
an ALTER TABLE statement and a list of extra (sql, params) tuples to
run once the field is altered.
"""
return (
(
self.sql_alter_column_type % {
"column": self.quote_name(new_field.column),
"type": new_type,
},
[],
),
[],
)
def _alter_many_to_many(self, model, old_field, new_field, strict):
"""Alter M2Ms to repoint their to= endpoints."""
# Rename the through table
if old_field.remote_field.through._meta.db_table != new_field.remote_field.through._meta.db_table:
self.alter_db_table(old_field.remote_field.through, old_field.remote_field.through._meta.db_table,
new_field.remote_field.through._meta.db_table)
# Repoint the FK to the other side
self.alter_field(
new_field.remote_field.through,
# We need the field that points to the target model, so we can tell alter_field to change it -
# this is m2m_reverse_field_name() (as opposed to m2m_field_name, which points to our model)
old_field.remote_field.through._meta.get_field(old_field.m2m_reverse_field_name()),
new_field.remote_field.through._meta.get_field(new_field.m2m_reverse_field_name()),
)
self.alter_field(
new_field.remote_field.through,
# for self-referential models we need to alter field from the other end too
old_field.remote_field.through._meta.get_field(old_field.m2m_field_name()),
new_field.remote_field.through._meta.get_field(new_field.m2m_field_name()),
)
def _create_index_name(self, table_name, column_names, suffix=""):
"""
Generate a unique name for an index/unique constraint.
The name is divided into 3 parts: the table name, the column names,
and a unique digest and suffix.
"""
_, table_name = split_identifier(table_name)
hash_suffix_part = '%s%s' % (names_digest(table_name, *column_names, length=8), suffix)
max_length = self.connection.ops.max_name_length() or 200
# If everything fits into max_length, use that name.
index_name = '%s_%s_%s' % (table_name, '_'.join(column_names), hash_suffix_part)
if len(index_name) <= max_length:
return index_name
# Shorten a long suffix.
if len(hash_suffix_part) > max_length / 3:
hash_suffix_part = hash_suffix_part[:max_length // 3]
other_length = (max_length - len(hash_suffix_part)) // 2 - 1
index_name = '%s_%s_%s' % (
table_name[:other_length],
'_'.join(column_names)[:other_length],
hash_suffix_part,
)
# Prepend D if needed to prevent the name from starting with an
# underscore or a number (not permitted on Oracle).
if index_name[0] == "_" or index_name[0].isdigit():
index_name = "D%s" % index_name[:-1]
return index_name
def _get_index_tablespace_sql(self, model, fields, db_tablespace=None):
if db_tablespace is None:
if len(fields) == 1 and fields[0].db_tablespace:
db_tablespace = fields[0].db_tablespace
elif model._meta.db_tablespace:
db_tablespace = model._meta.db_tablespace
if db_tablespace is not None:
return ' ' + self.connection.ops.tablespace_sql(db_tablespace)
return ''
def _index_condition_sql(self, condition):
if condition:
return ' WHERE ' + condition
return ''
def _create_index_sql(self, model, fields, *, name=None, suffix='', using='',
db_tablespace=None, col_suffixes=(), sql=None, opclasses=(),
condition=None):
"""
Return the SQL statement to create the index for one or several fields.
`sql` can be specified if the syntax differs from the standard (GIS
indexes, ...).
"""
tablespace_sql = self._get_index_tablespace_sql(model, fields, db_tablespace=db_tablespace)
columns = [field.column for field in fields]
sql_create_index = sql or self.sql_create_index
table = model._meta.db_table
def create_index_name(*args, **kwargs):
nonlocal name
if name is None:
name = self._create_index_name(*args, **kwargs)
return self.quote_name(name)
return Statement(
sql_create_index,
table=Table(table, self.quote_name),
name=IndexName(table, columns, suffix, create_index_name),
using=using,
columns=self._index_columns(table, columns, col_suffixes, opclasses),
extra=tablespace_sql,
condition=self._index_condition_sql(condition),
)
def _delete_index_sql(self, model, name, sql=None):
return Statement(
sql or self.sql_delete_index,
table=Table(model._meta.db_table, self.quote_name),
name=self.quote_name(name),
)
def _index_columns(self, table, columns, col_suffixes, opclasses):
return Columns(table, columns, self.quote_name, col_suffixes=col_suffixes)
def _model_indexes_sql(self, model):
"""
Return a list of all index SQL statements (field indexes,
index_together, Meta.indexes) for the specified model.
"""
if not model._meta.managed or model._meta.proxy or model._meta.swapped:
return []
output = []
for field in model._meta.local_fields:
output.extend(self._field_indexes_sql(model, field))
for field_names in model._meta.index_together:
fields = [model._meta.get_field(field) for field in field_names]
output.append(self._create_index_sql(model, fields, suffix="_idx"))
for index in model._meta.indexes:
output.append(index.create_sql(model, self))
return output
def _field_indexes_sql(self, model, field):
"""
Return a list of all index SQL statements for the specified field.
"""
output = []
if self._field_should_be_indexed(model, field):
output.append(self._create_index_sql(model, [field]))
return output
def _field_should_be_indexed(self, model, field):
return field.db_index and not field.unique
def _field_became_primary_key(self, old_field, new_field):
return not old_field.primary_key and new_field.primary_key
def _unique_should_be_added(self, old_field, new_field):
return (not old_field.unique and new_field.unique) or (
old_field.primary_key and not new_field.primary_key and new_field.unique
)
def _rename_field_sql(self, table, old_field, new_field, new_type):
return self.sql_rename_column % {
"table": self.quote_name(table),
"old_column": self.quote_name(old_field.column),
"new_column": self.quote_name(new_field.column),
"type": new_type,
}
def _create_fk_sql(self, model, field, suffix):
table = Table(model._meta.db_table, self.quote_name)
name = self._fk_constraint_name(model, field, suffix)
column = Columns(model._meta.db_table, [field.column], self.quote_name)
to_table = Table(field.target_field.model._meta.db_table, self.quote_name)
to_column = Columns(field.target_field.model._meta.db_table, [field.target_field.column], self.quote_name)
deferrable = self.connection.ops.deferrable_sql()
return Statement(
self.sql_create_fk,
table=table,
name=name,
column=column,
to_table=to_table,
to_column=to_column,
deferrable=deferrable,
)
def _fk_constraint_name(self, model, field, suffix):
def create_fk_name(*args, **kwargs):
return self.quote_name(self._create_index_name(*args, **kwargs))
return ForeignKeyName(
model._meta.db_table,
[field.column],
split_identifier(field.target_field.model._meta.db_table)[1],
[field.target_field.column],
suffix,
create_fk_name,
)
def _delete_fk_sql(self, model, name):
return self._delete_constraint_sql(self.sql_delete_fk, model, name)
def _deferrable_constraint_sql(self, deferrable):
if deferrable is None:
return ''
if deferrable == Deferrable.DEFERRED:
return ' DEFERRABLE INITIALLY DEFERRED'
if deferrable == Deferrable.IMMEDIATE:
return ' DEFERRABLE INITIALLY IMMEDIATE'
def _unique_sql(self, model, fields, name, condition=None, deferrable=None):
if (
deferrable and
not self.connection.features.supports_deferrable_unique_constraints
):
return None
if condition:
# Databases support conditional unique constraints via a unique
# index.
sql = self._create_unique_sql(model, fields, name=name, condition=condition)
if sql:
self.deferred_sql.append(sql)
return None
constraint = self.sql_unique_constraint % {
'columns': ', '.join(map(self.quote_name, fields)),
'deferrable': self._deferrable_constraint_sql(deferrable),
}
return self.sql_constraint % {
'name': self.quote_name(name),
'constraint': constraint,
}
def _create_unique_sql(self, model, columns, name=None, condition=None, deferrable=None):
if (
deferrable and
not self.connection.features.supports_deferrable_unique_constraints
):
return None
def create_unique_name(*args, **kwargs):
return self.quote_name(self._create_index_name(*args, **kwargs))
table = Table(model._meta.db_table, self.quote_name)
if name is None:
name = IndexName(model._meta.db_table, columns, '_uniq', create_unique_name)
else:
name = self.quote_name(name)
columns = Columns(table, columns, self.quote_name)
if condition:
if not self.connection.features.supports_partial_indexes:
return None
sql = self.sql_create_unique_index
else:
sql = self.sql_create_unique
return Statement(
sql,
table=table,
name=name,
columns=columns,
condition=self._index_condition_sql(condition),
deferrable=self._deferrable_constraint_sql(deferrable),
)
def _delete_unique_sql(self, model, name, condition=None, deferrable=None):
if (
deferrable and
not self.connection.features.supports_deferrable_unique_constraints
):
return None
if condition:
return (
self._delete_constraint_sql(self.sql_delete_index, model, name)
if self.connection.features.supports_partial_indexes else None
)
return self._delete_constraint_sql(self.sql_delete_unique, model, name)
def _check_sql(self, name, check):
return self.sql_constraint % {
'name': self.quote_name(name),
'constraint': self.sql_check_constraint % {'check': check},
}
def _create_check_sql(self, model, name, check):
return Statement(
self.sql_create_check,
table=Table(model._meta.db_table, self.quote_name),
name=self.quote_name(name),
check=check,
)
def _delete_check_sql(self, model, name):
return self._delete_constraint_sql(self.sql_delete_check, model, name)
def _delete_constraint_sql(self, template, model, name):
return Statement(
template,
table=Table(model._meta.db_table, self.quote_name),
name=self.quote_name(name),
)
def _constraint_names(self, model, column_names=None, unique=None,
primary_key=None, index=None, foreign_key=None,
check=None, type_=None, exclude=None):
"""Return all constraint names matching the columns and conditions."""
if column_names is not None:
column_names = [
self.connection.introspection.identifier_converter(name)
for name in column_names
]
with self.connection.cursor() as cursor:
constraints = self.connection.introspection.get_constraints(cursor, model._meta.db_table)
result = []
for name, infodict in constraints.items():
if column_names is None or column_names == infodict['columns']:
if unique is not None and infodict['unique'] != unique:
continue
if primary_key is not None and infodict['primary_key'] != primary_key:
continue
if index is not None and infodict['index'] != index:
continue
if check is not None and infodict['check'] != check:
continue
if foreign_key is not None and not infodict['foreign_key']:
continue
if type_ is not None and infodict['type'] != type_:
continue
if not exclude or name not in exclude:
result.append(name)
return result
def _delete_primary_key(self, model, strict=False):
constraint_names = self._constraint_names(model, primary_key=True)
if strict and len(constraint_names) != 1:
raise ValueError('Found wrong number (%s) of PK constraints for %s' % (
len(constraint_names),
model._meta.db_table,
))
for constraint_name in constraint_names:
self.execute(self._delete_primary_key_sql(model, constraint_name))
def _create_primary_key_sql(self, model, field):
return Statement(
self.sql_create_pk,
table=Table(model._meta.db_table, self.quote_name),
name=self.quote_name(
self._create_index_name(model._meta.db_table, [field.column], suffix="_pk")
),
columns=Columns(model._meta.db_table, [field.column], self.quote_name),
)
def _delete_primary_key_sql(self, model, name):
return self._delete_constraint_sql(self.sql_delete_pk, model, name)
def remove_procedure(self, procedure_name, param_types=()):
sql = self.sql_delete_procedure % {
'procedure': self.quote_name(procedure_name),
'param_types': ','.join(param_types),
}
self.execute(sql)
|
3fe2a2bab52acdcf9526905fb93041a506403f24c83f2b422667fa65866a713e | class BaseDatabaseClient:
"""Encapsulate backend-specific methods for opening a client shell."""
# This should be a string representing the name of the executable
# (e.g., "psql"). Subclasses must override this.
executable_name = None
def __init__(self, connection):
# connection is an instance of BaseDatabaseWrapper.
self.connection = connection
def runshell(self, parameters):
raise NotImplementedError('subclasses of BaseDatabaseClient must provide a runshell() method')
|
878114b14a08357a15b39b115a15281f994ff64da13ff9e1bafde5983821bb00 | import os
import sys
from io import StringIO
from django.apps import apps
from django.conf import settings
from django.core import serializers
from django.db import router
from django.db.transaction import atomic
# The prefix to put on the default database name when creating
# the test database.
TEST_DATABASE_PREFIX = 'test_'
class BaseDatabaseCreation:
"""
Encapsulate backend-specific differences pertaining to creation and
destruction of the test database.
"""
def __init__(self, connection):
self.connection = connection
def _nodb_cursor(self):
return self.connection._nodb_cursor()
def log(self, msg):
sys.stderr.write(msg + os.linesep)
def create_test_db(self, verbosity=1, autoclobber=False, serialize=True, keepdb=False):
"""
Create a test database, prompting the user for confirmation if the
database already exists. Return the name of the test database created.
"""
# Don't import django.core.management if it isn't needed.
from django.core.management import call_command
test_database_name = self._get_test_db_name()
if verbosity >= 1:
action = 'Creating'
if keepdb:
action = "Using existing"
self.log('%s test database for alias %s...' % (
action,
self._get_database_display_str(verbosity, test_database_name),
))
# We could skip this call if keepdb is True, but we instead
# give it the keepdb param. This is to handle the case
# where the test DB doesn't exist, in which case we need to
# create it, then just not destroy it. If we instead skip
# this, we will get an exception.
self._create_test_db(verbosity, autoclobber, keepdb)
self.connection.close()
settings.DATABASES[self.connection.alias]["NAME"] = test_database_name
self.connection.settings_dict["NAME"] = test_database_name
if self.connection.settings_dict['TEST']['MIGRATE']:
# We report migrate messages at one level lower than that
# requested. This ensures we don't get flooded with messages during
# testing (unless you really ask to be flooded).
call_command(
'migrate',
verbosity=max(verbosity - 1, 0),
interactive=False,
database=self.connection.alias,
run_syncdb=True,
)
# We then serialize the current state of the database into a string
# and store it on the connection. This slightly horrific process is so people
# who are testing on databases without transactions or who are using
# a TransactionTestCase still get a clean database on every test run.
if serialize:
self.connection._test_serialized_contents = self.serialize_db_to_string()
call_command('createcachetable', database=self.connection.alias)
# Ensure a connection for the side effect of initializing the test database.
self.connection.ensure_connection()
return test_database_name
def set_as_test_mirror(self, primary_settings_dict):
"""
Set this database up to be used in testing as a mirror of a primary
database whose settings are given.
"""
self.connection.settings_dict['NAME'] = primary_settings_dict['NAME']
def serialize_db_to_string(self):
"""
Serialize all data in the database into a JSON string.
Designed only for test runner usage; will not handle large
amounts of data.
"""
# Iteratively return every object for all models to serialize.
def get_objects():
from django.db.migrations.loader import MigrationLoader
loader = MigrationLoader(self.connection)
for app_config in apps.get_app_configs():
if (
app_config.models_module is not None and
app_config.label in loader.migrated_apps and
app_config.name not in settings.TEST_NON_SERIALIZED_APPS
):
for model in app_config.get_models():
if (
model._meta.can_migrate(self.connection) and
router.allow_migrate_model(self.connection.alias, model)
):
queryset = model._default_manager.using(
self.connection.alias,
).order_by(model._meta.pk.name)
yield from queryset.iterator()
# Serialize to a string
out = StringIO()
serializers.serialize("json", get_objects(), indent=None, stream=out)
return out.getvalue()
def deserialize_db_from_string(self, data):
"""
Reload the database with data from a string generated by
the serialize_db_to_string() method.
"""
data = StringIO(data)
table_names = set()
# Load data in a transaction to handle forward references and cycles.
with atomic(using=self.connection.alias):
# Disable constraint checks, because some databases (MySQL) doesn't
# support deferred checks.
with self.connection.constraint_checks_disabled():
for obj in serializers.deserialize('json', data, using=self.connection.alias):
obj.save()
table_names.add(obj.object.__class__._meta.db_table)
# Manually check for any invalid keys that might have been added,
# because constraint checks were disabled.
self.connection.check_constraints(table_names=table_names)
def _get_database_display_str(self, verbosity, database_name):
"""
Return display string for a database for use in various actions.
"""
return "'%s'%s" % (
self.connection.alias,
(" ('%s')" % database_name) if verbosity >= 2 else '',
)
def _get_test_db_name(self):
"""
Internal implementation - return the name of the test DB that will be
created. Only useful when called from create_test_db() and
_create_test_db() and when no external munging is done with the 'NAME'
settings.
"""
if self.connection.settings_dict['TEST']['NAME']:
return self.connection.settings_dict['TEST']['NAME']
return TEST_DATABASE_PREFIX + self.connection.settings_dict['NAME']
def _execute_create_test_db(self, cursor, parameters, keepdb=False):
cursor.execute('CREATE DATABASE %(dbname)s %(suffix)s' % parameters)
def _create_test_db(self, verbosity, autoclobber, keepdb=False):
"""
Internal implementation - create the test db tables.
"""
test_database_name = self._get_test_db_name()
test_db_params = {
'dbname': self.connection.ops.quote_name(test_database_name),
'suffix': self.sql_table_creation_suffix(),
}
# Create the test database and connect to it.
with self._nodb_cursor() as cursor:
try:
self._execute_create_test_db(cursor, test_db_params, keepdb)
except Exception as e:
# if we want to keep the db, then no need to do any of the below,
# just return and skip it all.
if keepdb:
return test_database_name
self.log('Got an error creating the test database: %s' % e)
if not autoclobber:
confirm = input(
"Type 'yes' if you would like to try deleting the test "
"database '%s', or 'no' to cancel: " % test_database_name)
if autoclobber or confirm == 'yes':
try:
if verbosity >= 1:
self.log('Destroying old test database for alias %s...' % (
self._get_database_display_str(verbosity, test_database_name),
))
cursor.execute('DROP DATABASE %(dbname)s' % test_db_params)
self._execute_create_test_db(cursor, test_db_params, keepdb)
except Exception as e:
self.log('Got an error recreating the test database: %s' % e)
sys.exit(2)
else:
self.log('Tests cancelled.')
sys.exit(1)
return test_database_name
def clone_test_db(self, suffix, verbosity=1, autoclobber=False, keepdb=False):
"""
Clone a test database.
"""
source_database_name = self.connection.settings_dict['NAME']
if verbosity >= 1:
action = 'Cloning test database'
if keepdb:
action = 'Using existing clone'
self.log('%s for alias %s...' % (
action,
self._get_database_display_str(verbosity, source_database_name),
))
# We could skip this call if keepdb is True, but we instead
# give it the keepdb param. See create_test_db for details.
self._clone_test_db(suffix, verbosity, keepdb)
def get_test_db_clone_settings(self, suffix):
"""
Return a modified connection settings dict for the n-th clone of a DB.
"""
# When this function is called, the test database has been created
# already and its name has been copied to settings_dict['NAME'] so
# we don't need to call _get_test_db_name.
orig_settings_dict = self.connection.settings_dict
return {**orig_settings_dict, 'NAME': '{}_{}'.format(orig_settings_dict['NAME'], suffix)}
def _clone_test_db(self, suffix, verbosity, keepdb=False):
"""
Internal implementation - duplicate the test db tables.
"""
raise NotImplementedError(
"The database backend doesn't support cloning databases. "
"Disable the option to run tests in parallel processes.")
def destroy_test_db(self, old_database_name=None, verbosity=1, keepdb=False, suffix=None):
"""
Destroy a test database, prompting the user for confirmation if the
database already exists.
"""
self.connection.close()
if suffix is None:
test_database_name = self.connection.settings_dict['NAME']
else:
test_database_name = self.get_test_db_clone_settings(suffix)['NAME']
if verbosity >= 1:
action = 'Destroying'
if keepdb:
action = 'Preserving'
self.log('%s test database for alias %s...' % (
action,
self._get_database_display_str(verbosity, test_database_name),
))
# if we want to preserve the database
# skip the actual destroying piece.
if not keepdb:
self._destroy_test_db(test_database_name, verbosity)
# Restore the original database name
if old_database_name is not None:
settings.DATABASES[self.connection.alias]["NAME"] = old_database_name
self.connection.settings_dict["NAME"] = old_database_name
def _destroy_test_db(self, test_database_name, verbosity):
"""
Internal implementation - remove the test db tables.
"""
# Remove the test database to clean up after
# ourselves. Connect to the previous database (not the test database)
# to do so, because it's not allowed to delete a database while being
# connected to it.
with self._nodb_cursor() as cursor:
cursor.execute("DROP DATABASE %s"
% self.connection.ops.quote_name(test_database_name))
def sql_table_creation_suffix(self):
"""
SQL to append to the end of the test table creation statements.
"""
return ''
def test_db_signature(self):
"""
Return a tuple with elements of self.connection.settings_dict (a
DATABASES setting value) that uniquely identify a database
accordingly to the RDBMS particularities.
"""
settings_dict = self.connection.settings_dict
return (
settings_dict['HOST'],
settings_dict['PORT'],
settings_dict['ENGINE'],
self._get_test_db_name(),
)
|
535d526c1f7595c5b369964fc58f7a0a293db3dc0eeb5726fdf3b19d7f82bf3a | from django.core import checks
from django.db.backends.base.validation import BaseDatabaseValidation
from django.utils.version import get_docs_version
class DatabaseValidation(BaseDatabaseValidation):
def check(self, **kwargs):
issues = super().check(**kwargs)
issues.extend(self._check_sql_mode(**kwargs))
return issues
def _check_sql_mode(self, **kwargs):
if not (self.connection.sql_mode & {'STRICT_TRANS_TABLES', 'STRICT_ALL_TABLES'}):
return [checks.Warning(
"%s Strict Mode is not set for database connection '%s'"
% (self.connection.display_name, self.connection.alias),
hint=(
"%s's Strict Mode fixes many data integrity problems in "
"%s, such as data truncation upon insertion, by "
"escalating warnings into errors. It is strongly "
"recommended you activate it. See: "
"https://docs.djangoproject.com/en/%s/ref/databases/#mysql-sql-mode"
% (
self.connection.display_name,
self.connection.display_name,
get_docs_version(),
),
),
id='mysql.W002',
)]
return []
def check_field_type(self, field, field_type):
"""
MySQL has the following field length restriction:
No character (varchar) fields can have a length exceeding 255
characters if they have a unique index on them.
MySQL doesn't support a database index on some data types.
"""
errors = []
if (field_type.startswith('varchar') and field.unique and
(field.max_length is None or int(field.max_length) > 255)):
errors.append(
checks.Warning(
'%s may not allow unique CharFields to have a max_length '
'> 255.' % self.connection.display_name,
obj=field,
hint=(
'See: https://docs.djangoproject.com/en/%s/ref/'
'databases/#mysql-character-fields' % get_docs_version()
),
id='mysql.W003',
)
)
if field.db_index and field_type.lower() in self.connection._limited_data_types:
errors.append(
checks.Warning(
'%s does not support a database index on %s columns.'
% (self.connection.display_name, field_type),
hint=(
"An index won't be created. Silence this warning if "
"you don't care about it."
),
obj=field,
id='fields.W162',
)
)
return errors
|
439a0ee6bec0701f6157a8404443117abab9367c80395306505d55f77851bc39 | import operator
from django.db.backends.base.features import BaseDatabaseFeatures
from django.utils.functional import cached_property
class DatabaseFeatures(BaseDatabaseFeatures):
empty_fetchmany_value = ()
allows_group_by_pk = True
related_fields_match_type = True
# MySQL doesn't support sliced subqueries with IN/ALL/ANY/SOME.
allow_sliced_subqueries_with_in = False
has_select_for_update = True
supports_forward_references = False
supports_regex_backreferencing = False
supports_date_lookup_using_string = False
can_introspect_autofield = True
can_introspect_binary_field = False
can_introspect_duration_field = False
can_introspect_small_integer_field = True
can_introspect_positive_integer_field = True
introspected_boolean_field_type = 'IntegerField'
supports_index_column_ordering = False
supports_timezones = False
requires_explicit_null_ordering_when_grouping = True
allows_auto_pk_0 = False
can_release_savepoints = True
atomic_transactions = False
can_clone_databases = True
supports_temporal_subtraction = True
supports_select_intersection = False
supports_select_difference = False
supports_slicing_ordering_in_compound = True
supports_index_on_text_field = False
has_case_insensitive_like = False
create_test_procedure_without_params_sql = """
CREATE PROCEDURE test_procedure ()
BEGIN
DECLARE V_I INTEGER;
SET V_I = 1;
END;
"""
create_test_procedure_with_int_param_sql = """
CREATE PROCEDURE test_procedure (P_I INTEGER)
BEGIN
DECLARE V_I INTEGER;
SET V_I = P_I;
END;
"""
db_functions_convert_bytes_to_str = True
# Neither MySQL nor MariaDB support partial indexes.
supports_partial_indexes = False
supports_order_by_nulls_modifier = False
order_by_nulls_first = True
@cached_property
def _mysql_storage_engine(self):
"Internal method used in Django tests. Don't rely on this from your code"
with self.connection.cursor() as cursor:
cursor.execute("SELECT ENGINE FROM INFORMATION_SCHEMA.ENGINES WHERE SUPPORT = 'DEFAULT'")
result = cursor.fetchone()
return result[0]
@cached_property
def update_can_self_select(self):
return self.connection.mysql_is_mariadb and self.connection.mysql_version >= (10, 3, 2)
@cached_property
def can_introspect_foreign_keys(self):
"Confirm support for introspected foreign keys"
return self._mysql_storage_engine != 'MyISAM'
@cached_property
def can_return_columns_from_insert(self):
return self.connection.mysql_is_mariadb and self.connection.mysql_version >= (10, 5, 0)
can_return_rows_from_bulk_insert = property(operator.attrgetter('can_return_columns_from_insert'))
@cached_property
def has_zoneinfo_database(self):
# Test if the time zone definitions are installed. CONVERT_TZ returns
# NULL if 'UTC' timezone isn't loaded into the mysql.time_zone.
with self.connection.cursor() as cursor:
cursor.execute("SELECT CONVERT_TZ('2001-01-01 01:00:00', 'UTC', 'UTC')")
return cursor.fetchone()[0] is not None
@cached_property
def is_sql_auto_is_null_enabled(self):
with self.connection.cursor() as cursor:
cursor.execute('SELECT @@SQL_AUTO_IS_NULL')
result = cursor.fetchone()
return result and result[0] == 1
@cached_property
def supports_over_clause(self):
if self.connection.mysql_is_mariadb:
return True
return self.connection.mysql_version >= (8, 0, 2)
supports_frame_range_fixed_distance = property(operator.attrgetter('supports_over_clause'))
@cached_property
def supports_column_check_constraints(self):
if self.connection.mysql_is_mariadb:
return self.connection.mysql_version >= (10, 2, 1)
return self.connection.mysql_version >= (8, 0, 16)
supports_table_check_constraints = property(operator.attrgetter('supports_column_check_constraints'))
@cached_property
def can_introspect_check_constraints(self):
if self.connection.mysql_is_mariadb:
version = self.connection.mysql_version
return (version >= (10, 2, 22) and version < (10, 3)) or version >= (10, 3, 10)
return self.connection.mysql_version >= (8, 0, 16)
@cached_property
def has_select_for_update_skip_locked(self):
return not self.connection.mysql_is_mariadb and self.connection.mysql_version >= (8, 0, 1)
@cached_property
def has_select_for_update_nowait(self):
if self.connection.mysql_is_mariadb:
return self.connection.mysql_version >= (10, 3, 0)
return self.connection.mysql_version >= (8, 0, 1)
@cached_property
def needs_explain_extended(self):
# EXTENDED is deprecated (and not required) in MySQL 5.7.
return not self.connection.mysql_is_mariadb and self.connection.mysql_version < (5, 7)
@cached_property
def supports_explain_analyze(self):
return self.connection.mysql_is_mariadb or self.connection.mysql_version >= (8, 0, 18)
@cached_property
def supported_explain_formats(self):
# Alias MySQL's TRADITIONAL to TEXT for consistency with other
# backends.
formats = {'JSON', 'TEXT', 'TRADITIONAL'}
if not self.connection.mysql_is_mariadb and self.connection.mysql_version >= (8, 0, 16):
formats.add('TREE')
return formats
@cached_property
def supports_transactions(self):
"""
All storage engines except MyISAM support transactions.
"""
return self._mysql_storage_engine != 'MyISAM'
@cached_property
def ignores_table_name_case(self):
with self.connection.cursor() as cursor:
cursor.execute('SELECT @@LOWER_CASE_TABLE_NAMES')
result = cursor.fetchone()
return result and result[0] != 0
@cached_property
def supports_default_in_lead_lag(self):
# To be added in https://jira.mariadb.org/browse/MDEV-12981.
return not self.connection.mysql_is_mariadb
@cached_property
def supports_json_field(self):
if self.connection.mysql_is_mariadb:
return self.connection.mysql_version >= (10, 2, 7)
return self.connection.mysql_version >= (5, 7, 8)
@cached_property
def can_introspect_json_field(self):
if self.connection.mysql_is_mariadb:
return self.supports_json_field and self.can_introspect_check_constraints
return self.supports_json_field
|
dd044604e34fe42783071852119d8ed0b8fb1e041e82c0023a821e2fc6228b6a | from collections import namedtuple
import sqlparse
from MySQLdb.constants import FIELD_TYPE
from django.db.backends.base.introspection import (
BaseDatabaseIntrospection, FieldInfo as BaseFieldInfo, TableInfo,
)
from django.db.models import Index
from django.utils.datastructures import OrderedSet
FieldInfo = namedtuple('FieldInfo', BaseFieldInfo._fields + ('extra', 'is_unsigned', 'has_json_constraint'))
InfoLine = namedtuple('InfoLine', 'col_name data_type max_len num_prec num_scale extra column_default is_unsigned')
class DatabaseIntrospection(BaseDatabaseIntrospection):
data_types_reverse = {
FIELD_TYPE.BLOB: 'TextField',
FIELD_TYPE.CHAR: 'CharField',
FIELD_TYPE.DECIMAL: 'DecimalField',
FIELD_TYPE.NEWDECIMAL: 'DecimalField',
FIELD_TYPE.DATE: 'DateField',
FIELD_TYPE.DATETIME: 'DateTimeField',
FIELD_TYPE.DOUBLE: 'FloatField',
FIELD_TYPE.FLOAT: 'FloatField',
FIELD_TYPE.INT24: 'IntegerField',
FIELD_TYPE.JSON: 'JSONField',
FIELD_TYPE.LONG: 'IntegerField',
FIELD_TYPE.LONGLONG: 'BigIntegerField',
FIELD_TYPE.SHORT: 'SmallIntegerField',
FIELD_TYPE.STRING: 'CharField',
FIELD_TYPE.TIME: 'TimeField',
FIELD_TYPE.TIMESTAMP: 'DateTimeField',
FIELD_TYPE.TINY: 'IntegerField',
FIELD_TYPE.TINY_BLOB: 'TextField',
FIELD_TYPE.MEDIUM_BLOB: 'TextField',
FIELD_TYPE.LONG_BLOB: 'TextField',
FIELD_TYPE.VAR_STRING: 'CharField',
}
def get_field_type(self, data_type, description):
field_type = super().get_field_type(data_type, description)
if 'auto_increment' in description.extra:
if field_type == 'IntegerField':
return 'AutoField'
elif field_type == 'BigIntegerField':
return 'BigAutoField'
elif field_type == 'SmallIntegerField':
return 'SmallAutoField'
if description.is_unsigned:
if field_type == 'BigIntegerField':
return 'PositiveBigIntegerField'
elif field_type == 'IntegerField':
return 'PositiveIntegerField'
elif field_type == 'SmallIntegerField':
return 'PositiveSmallIntegerField'
# JSON data type is an alias for LONGTEXT in MariaDB, use check
# constraints clauses to introspect JSONField.
if description.has_json_constraint:
return 'JSONField'
return field_type
def get_table_list(self, cursor):
"""Return a list of table and view names in the current database."""
cursor.execute("SHOW FULL TABLES")
return [TableInfo(row[0], {'BASE TABLE': 't', 'VIEW': 'v'}.get(row[1]))
for row in cursor.fetchall()]
def get_table_description(self, cursor, table_name):
"""
Return a description of the table with the DB-API cursor.description
interface."
"""
json_constraints = {}
if self.connection.mysql_is_mariadb and self.connection.features.can_introspect_json_field:
# JSON data type is an alias for LONGTEXT in MariaDB, select
# JSON_VALID() constraints to introspect JSONField.
cursor.execute("""
SELECT c.constraint_name AS column_name
FROM information_schema.check_constraints AS c
WHERE
c.table_name = %s AND
LOWER(c.check_clause) = 'json_valid(`' + LOWER(c.constraint_name) + '`)' AND
c.constraint_schema = DATABASE()
""", [table_name])
json_constraints = {row[0] for row in cursor.fetchall()}
# information_schema database gives more accurate results for some figures:
# - varchar length returned by cursor.description is an internal length,
# not visible length (#5725)
# - precision and scale (for decimal fields) (#5014)
# - auto_increment is not available in cursor.description
cursor.execute("""
SELECT
column_name, data_type, character_maximum_length,
numeric_precision, numeric_scale, extra, column_default,
CASE
WHEN column_type LIKE '%% unsigned' THEN 1
ELSE 0
END AS is_unsigned
FROM information_schema.columns
WHERE table_name = %s AND table_schema = DATABASE()""", [table_name])
field_info = {line[0]: InfoLine(*line) for line in cursor.fetchall()}
cursor.execute("SELECT * FROM %s LIMIT 1" % self.connection.ops.quote_name(table_name))
def to_int(i):
return int(i) if i is not None else i
fields = []
for line in cursor.description:
info = field_info[line[0]]
fields.append(FieldInfo(
*line[:3],
to_int(info.max_len) or line[3],
to_int(info.num_prec) or line[4],
to_int(info.num_scale) or line[5],
line[6],
info.column_default,
info.extra,
info.is_unsigned,
line[0] in json_constraints,
))
return fields
def get_sequences(self, cursor, table_name, table_fields=()):
for field_info in self.get_table_description(cursor, table_name):
if 'auto_increment' in field_info.extra:
# MySQL allows only one auto-increment column per table.
return [{'table': table_name, 'column': field_info.name}]
return []
def get_relations(self, cursor, table_name):
"""
Return a dictionary of {field_name: (field_name_other_table, other_table)}
representing all relationships to the given table.
"""
constraints = self.get_key_columns(cursor, table_name)
relations = {}
for my_fieldname, other_table, other_field in constraints:
relations[my_fieldname] = (other_field, other_table)
return relations
def get_key_columns(self, cursor, table_name):
"""
Return a list of (column_name, referenced_table_name, referenced_column_name)
for all key columns in the given table.
"""
key_columns = []
cursor.execute("""
SELECT column_name, referenced_table_name, referenced_column_name
FROM information_schema.key_column_usage
WHERE table_name = %s
AND table_schema = DATABASE()
AND referenced_table_name IS NOT NULL
AND referenced_column_name IS NOT NULL""", [table_name])
key_columns.extend(cursor.fetchall())
return key_columns
def get_storage_engine(self, cursor, table_name):
"""
Retrieve the storage engine for a given table. Return the default
storage engine if the table doesn't exist.
"""
cursor.execute(
"SELECT engine "
"FROM information_schema.tables "
"WHERE table_name = %s", [table_name])
result = cursor.fetchone()
if not result:
return self.connection.features._mysql_storage_engine
return result[0]
def _parse_constraint_columns(self, check_clause, columns):
check_columns = OrderedSet()
statement = sqlparse.parse(check_clause)[0]
tokens = (token for token in statement.flatten() if not token.is_whitespace)
for token in tokens:
if (
token.ttype == sqlparse.tokens.Name and
self.connection.ops.quote_name(token.value) == token.value and
token.value[1:-1] in columns
):
check_columns.add(token.value[1:-1])
return check_columns
def get_constraints(self, cursor, table_name):
"""
Retrieve any constraints or keys (unique, pk, fk, check, index) across
one or more columns.
"""
constraints = {}
# Get the actual constraint names and columns
name_query = """
SELECT kc.`constraint_name`, kc.`column_name`,
kc.`referenced_table_name`, kc.`referenced_column_name`
FROM information_schema.key_column_usage AS kc
WHERE
kc.table_schema = DATABASE() AND
kc.table_name = %s
ORDER BY kc.`ordinal_position`
"""
cursor.execute(name_query, [table_name])
for constraint, column, ref_table, ref_column in cursor.fetchall():
if constraint not in constraints:
constraints[constraint] = {
'columns': OrderedSet(),
'primary_key': False,
'unique': False,
'index': False,
'check': False,
'foreign_key': (ref_table, ref_column) if ref_column else None,
}
constraints[constraint]['columns'].add(column)
# Now get the constraint types
type_query = """
SELECT c.constraint_name, c.constraint_type
FROM information_schema.table_constraints AS c
WHERE
c.table_schema = DATABASE() AND
c.table_name = %s
"""
cursor.execute(type_query, [table_name])
for constraint, kind in cursor.fetchall():
if kind.lower() == "primary key":
constraints[constraint]['primary_key'] = True
constraints[constraint]['unique'] = True
elif kind.lower() == "unique":
constraints[constraint]['unique'] = True
# Add check constraints.
if self.connection.features.can_introspect_check_constraints:
unnamed_constraints_index = 0
columns = {info.name for info in self.get_table_description(cursor, table_name)}
if self.connection.mysql_is_mariadb:
type_query = """
SELECT c.constraint_name, c.check_clause
FROM information_schema.check_constraints AS c
WHERE
c.constraint_schema = DATABASE() AND
c.table_name = %s
"""
else:
type_query = """
SELECT cc.constraint_name, cc.check_clause
FROM
information_schema.check_constraints AS cc,
information_schema.table_constraints AS tc
WHERE
cc.constraint_schema = DATABASE() AND
tc.table_schema = cc.constraint_schema AND
cc.constraint_name = tc.constraint_name AND
tc.constraint_type = 'CHECK' AND
tc.table_name = %s
"""
cursor.execute(type_query, [table_name])
for constraint, check_clause in cursor.fetchall():
constraint_columns = self._parse_constraint_columns(check_clause, columns)
# Ensure uniqueness of unnamed constraints. Unnamed unique
# and check columns constraints have the same name as
# a column.
if set(constraint_columns) == {constraint}:
unnamed_constraints_index += 1
constraint = '__unnamed_constraint_%s__' % unnamed_constraints_index
constraints[constraint] = {
'columns': constraint_columns,
'primary_key': False,
'unique': False,
'index': False,
'check': True,
'foreign_key': None,
}
# Now add in the indexes
cursor.execute("SHOW INDEX FROM %s" % self.connection.ops.quote_name(table_name))
for table, non_unique, index, colseq, column, type_ in [x[:5] + (x[10],) for x in cursor.fetchall()]:
if index not in constraints:
constraints[index] = {
'columns': OrderedSet(),
'primary_key': False,
'unique': False,
'check': False,
'foreign_key': None,
}
constraints[index]['index'] = True
constraints[index]['type'] = Index.suffix if type_ == 'BTREE' else type_.lower()
constraints[index]['columns'].add(column)
# Convert the sorted sets to lists
for constraint in constraints.values():
constraint['columns'] = list(constraint['columns'])
return constraints
|
8e7b4b64746570cd40a93f6fcf63f902dde00a4e093d7ebc65043663407a4f29 | """
MySQL database backend for Django.
Requires mysqlclient: https://pypi.org/project/mysqlclient/
"""
from django.core.exceptions import ImproperlyConfigured
from django.db import IntegrityError
from django.db.backends import utils as backend_utils
from django.db.backends.base.base import BaseDatabaseWrapper
from django.utils.asyncio import async_unsafe
from django.utils.functional import cached_property
from django.utils.regex_helper import _lazy_re_compile
try:
import MySQLdb as Database
except ImportError as err:
raise ImproperlyConfigured(
'Error loading MySQLdb module.\n'
'Did you install mysqlclient?'
) from err
from MySQLdb.constants import CLIENT, FIELD_TYPE # isort:skip
from MySQLdb.converters import conversions # isort:skip
# Some of these import MySQLdb, so import them after checking if it's installed.
from .client import DatabaseClient # isort:skip
from .creation import DatabaseCreation # isort:skip
from .features import DatabaseFeatures # isort:skip
from .introspection import DatabaseIntrospection # isort:skip
from .operations import DatabaseOperations # isort:skip
from .schema import DatabaseSchemaEditor # isort:skip
from .validation import DatabaseValidation # isort:skip
version = Database.version_info
if version < (1, 4, 0):
raise ImproperlyConfigured('mysqlclient 1.4.0 or newer is required; you have %s.' % Database.__version__)
# MySQLdb returns TIME columns as timedelta -- they are more like timedelta in
# terms of actual behavior as they are signed and include days -- and Django
# expects time.
django_conversions = {
**conversions,
**{FIELD_TYPE.TIME: backend_utils.typecast_time},
}
# This should match the numerical portion of the version numbers (we can treat
# versions like 5.0.24 and 5.0.24a as the same).
server_version_re = _lazy_re_compile(r'(\d{1,2})\.(\d{1,2})\.(\d{1,2})')
class CursorWrapper:
"""
A thin wrapper around MySQLdb's normal cursor class that catches particular
exception instances and reraises them with the correct types.
Implemented as a wrapper, rather than a subclass, so that it isn't stuck
to the particular underlying representation returned by Connection.cursor().
"""
codes_for_integrityerror = (
1048, # Column cannot be null
1690, # BIGINT UNSIGNED value is out of range
3819, # CHECK constraint is violated
4025, # CHECK constraint failed
)
def __init__(self, cursor):
self.cursor = cursor
def execute(self, query, args=None):
try:
# args is None means no string interpolation
return self.cursor.execute(query, args)
except Database.OperationalError as e:
# Map some error codes to IntegrityError, since they seem to be
# misclassified and Django would prefer the more logical place.
if e.args[0] in self.codes_for_integrityerror:
raise IntegrityError(*tuple(e.args))
raise
def executemany(self, query, args):
try:
return self.cursor.executemany(query, args)
except Database.OperationalError as e:
# Map some error codes to IntegrityError, since they seem to be
# misclassified and Django would prefer the more logical place.
if e.args[0] in self.codes_for_integrityerror:
raise IntegrityError(*tuple(e.args))
raise
def __getattr__(self, attr):
return getattr(self.cursor, attr)
def __iter__(self):
return iter(self.cursor)
class DatabaseWrapper(BaseDatabaseWrapper):
vendor = 'mysql'
# This dictionary maps Field objects to their associated MySQL column
# types, as strings. Column-type strings can contain format strings; they'll
# be interpolated against the values of Field.__dict__ before being output.
# If a column type is set to None, it won't be included in the output.
data_types = {
'AutoField': 'integer AUTO_INCREMENT',
'BigAutoField': 'bigint AUTO_INCREMENT',
'BinaryField': 'longblob',
'BooleanField': 'bool',
'CharField': 'varchar(%(max_length)s)',
'DateField': 'date',
'DateTimeField': 'datetime(6)',
'DecimalField': 'numeric(%(max_digits)s, %(decimal_places)s)',
'DurationField': 'bigint',
'FileField': 'varchar(%(max_length)s)',
'FilePathField': 'varchar(%(max_length)s)',
'FloatField': 'double precision',
'IntegerField': 'integer',
'BigIntegerField': 'bigint',
'IPAddressField': 'char(15)',
'GenericIPAddressField': 'char(39)',
'JSONField': 'json',
'NullBooleanField': 'bool',
'OneToOneField': 'integer',
'PositiveBigIntegerField': 'bigint UNSIGNED',
'PositiveIntegerField': 'integer UNSIGNED',
'PositiveSmallIntegerField': 'smallint UNSIGNED',
'SlugField': 'varchar(%(max_length)s)',
'SmallAutoField': 'smallint AUTO_INCREMENT',
'SmallIntegerField': 'smallint',
'TextField': 'longtext',
'TimeField': 'time(6)',
'UUIDField': 'char(32)',
}
# For these data types:
# - MySQL < 8.0.13 and MariaDB < 10.2.1 don't accept default values and
# implicitly treat them as nullable
# - all versions of MySQL and MariaDB don't support full width database
# indexes
_limited_data_types = (
'tinyblob', 'blob', 'mediumblob', 'longblob', 'tinytext', 'text',
'mediumtext', 'longtext', 'json',
)
operators = {
'exact': '= %s',
'iexact': 'LIKE %s',
'contains': 'LIKE BINARY %s',
'icontains': 'LIKE %s',
'gt': '> %s',
'gte': '>= %s',
'lt': '< %s',
'lte': '<= %s',
'startswith': 'LIKE BINARY %s',
'endswith': 'LIKE BINARY %s',
'istartswith': 'LIKE %s',
'iendswith': 'LIKE %s',
}
# The patterns below are used to generate SQL pattern lookup clauses when
# the right-hand side of the lookup isn't a raw string (it might be an expression
# or the result of a bilateral transformation).
# In those cases, special characters for LIKE operators (e.g. \, *, _) should be
# escaped on database side.
#
# Note: we use str.format() here for readability as '%' is used as a wildcard for
# the LIKE operator.
pattern_esc = r"REPLACE(REPLACE(REPLACE({}, '\\', '\\\\'), '%%', '\%%'), '_', '\_')"
pattern_ops = {
'contains': "LIKE BINARY CONCAT('%%', {}, '%%')",
'icontains': "LIKE CONCAT('%%', {}, '%%')",
'startswith': "LIKE BINARY CONCAT({}, '%%')",
'istartswith': "LIKE CONCAT({}, '%%')",
'endswith': "LIKE BINARY CONCAT('%%', {})",
'iendswith': "LIKE CONCAT('%%', {})",
}
isolation_levels = {
'read uncommitted',
'read committed',
'repeatable read',
'serializable',
}
Database = Database
SchemaEditorClass = DatabaseSchemaEditor
# Classes instantiated in __init__().
client_class = DatabaseClient
creation_class = DatabaseCreation
features_class = DatabaseFeatures
introspection_class = DatabaseIntrospection
ops_class = DatabaseOperations
validation_class = DatabaseValidation
def get_connection_params(self):
kwargs = {
'conv': django_conversions,
'charset': 'utf8',
}
settings_dict = self.settings_dict
if settings_dict['USER']:
kwargs['user'] = settings_dict['USER']
if settings_dict['NAME']:
kwargs['db'] = settings_dict['NAME']
if settings_dict['PASSWORD']:
kwargs['passwd'] = settings_dict['PASSWORD']
if settings_dict['HOST'].startswith('/'):
kwargs['unix_socket'] = settings_dict['HOST']
elif settings_dict['HOST']:
kwargs['host'] = settings_dict['HOST']
if settings_dict['PORT']:
kwargs['port'] = int(settings_dict['PORT'])
# We need the number of potentially affected rows after an
# "UPDATE", not the number of changed rows.
kwargs['client_flag'] = CLIENT.FOUND_ROWS
# Validate the transaction isolation level, if specified.
options = settings_dict['OPTIONS'].copy()
isolation_level = options.pop('isolation_level', 'read committed')
if isolation_level:
isolation_level = isolation_level.lower()
if isolation_level not in self.isolation_levels:
raise ImproperlyConfigured(
"Invalid transaction isolation level '%s' specified.\n"
"Use one of %s, or None." % (
isolation_level,
', '.join("'%s'" % s for s in sorted(self.isolation_levels))
))
self.isolation_level = isolation_level
kwargs.update(options)
return kwargs
@async_unsafe
def get_new_connection(self, conn_params):
return Database.connect(**conn_params)
def init_connection_state(self):
assignments = []
if self.features.is_sql_auto_is_null_enabled:
# SQL_AUTO_IS_NULL controls whether an AUTO_INCREMENT column on
# a recently inserted row will return when the field is tested
# for NULL. Disabling this brings this aspect of MySQL in line
# with SQL standards.
assignments.append('SET SQL_AUTO_IS_NULL = 0')
if self.isolation_level:
assignments.append('SET SESSION TRANSACTION ISOLATION LEVEL %s' % self.isolation_level.upper())
if assignments:
with self.cursor() as cursor:
cursor.execute('; '.join(assignments))
@async_unsafe
def create_cursor(self, name=None):
cursor = self.connection.cursor()
return CursorWrapper(cursor)
def _rollback(self):
try:
BaseDatabaseWrapper._rollback(self)
except Database.NotSupportedError:
pass
def _set_autocommit(self, autocommit):
with self.wrap_database_errors:
self.connection.autocommit(autocommit)
def disable_constraint_checking(self):
"""
Disable foreign key checks, primarily for use in adding rows with
forward references. Always return True to indicate constraint checks
need to be re-enabled.
"""
with self.cursor() as cursor:
cursor.execute('SET foreign_key_checks=0')
return True
def enable_constraint_checking(self):
"""
Re-enable foreign key checks after they have been disabled.
"""
# Override needs_rollback in case constraint_checks_disabled is
# nested inside transaction.atomic.
self.needs_rollback, needs_rollback = False, self.needs_rollback
try:
with self.cursor() as cursor:
cursor.execute('SET foreign_key_checks=1')
finally:
self.needs_rollback = needs_rollback
def check_constraints(self, table_names=None):
"""
Check each table name in `table_names` for rows with invalid foreign
key references. This method is intended to be used in conjunction with
`disable_constraint_checking()` and `enable_constraint_checking()`, to
determine if rows with invalid references were entered while constraint
checks were off.
"""
with self.cursor() as cursor:
if table_names is None:
table_names = self.introspection.table_names(cursor)
for table_name in table_names:
primary_key_column_name = self.introspection.get_primary_key_column(cursor, table_name)
if not primary_key_column_name:
continue
key_columns = self.introspection.get_key_columns(cursor, table_name)
for column_name, referenced_table_name, referenced_column_name in key_columns:
cursor.execute(
"""
SELECT REFERRING.`%s`, REFERRING.`%s` FROM `%s` as REFERRING
LEFT JOIN `%s` as REFERRED
ON (REFERRING.`%s` = REFERRED.`%s`)
WHERE REFERRING.`%s` IS NOT NULL AND REFERRED.`%s` IS NULL
""" % (
primary_key_column_name, column_name, table_name,
referenced_table_name, column_name, referenced_column_name,
column_name, referenced_column_name,
)
)
for bad_row in cursor.fetchall():
raise IntegrityError(
"The row in table '%s' with primary key '%s' has an invalid "
"foreign key: %s.%s contains a value '%s' that does not "
"have a corresponding value in %s.%s."
% (
table_name, bad_row[0], table_name, column_name,
bad_row[1], referenced_table_name, referenced_column_name,
)
)
def is_usable(self):
try:
self.connection.ping()
except Database.Error:
return False
else:
return True
@cached_property
def display_name(self):
return 'MariaDB' if self.mysql_is_mariadb else 'MySQL'
@cached_property
def data_type_check_constraints(self):
if self.features.supports_column_check_constraints:
check_constraints = {
'PositiveBigIntegerField': '`%(column)s` >= 0',
'PositiveIntegerField': '`%(column)s` >= 0',
'PositiveSmallIntegerField': '`%(column)s` >= 0',
}
if self.mysql_is_mariadb and self.mysql_version < (10, 4, 3):
# MariaDB < 10.4.3 doesn't automatically use the JSON_VALID as
# a check constraint.
check_constraints['JSONField'] = 'JSON_VALID(`%(column)s`)'
return check_constraints
return {}
@cached_property
def mysql_server_info(self):
with self.temporary_connection() as cursor:
cursor.execute('SELECT VERSION()')
return cursor.fetchone()[0]
@cached_property
def mysql_version(self):
match = server_version_re.match(self.mysql_server_info)
if not match:
raise Exception('Unable to determine MySQL version from version string %r' % self.mysql_server_info)
return tuple(int(x) for x in match.groups())
@cached_property
def mysql_is_mariadb(self):
return 'mariadb' in self.mysql_server_info.lower()
@cached_property
def sql_mode(self):
with self.cursor() as cursor:
cursor.execute('SELECT @@sql_mode')
sql_mode = cursor.fetchone()
return set(sql_mode[0].split(',') if sql_mode else ())
|
49675a148bf64a0c213411dc7cc729291e947b0736f38e55964735122277749a | import uuid
from django.conf import settings
from django.db.backends.base.operations import BaseDatabaseOperations
from django.utils import timezone
from django.utils.duration import duration_microseconds
from django.utils.encoding import force_str
class DatabaseOperations(BaseDatabaseOperations):
compiler_module = "django.db.backends.mysql.compiler"
# MySQL stores positive fields as UNSIGNED ints.
integer_field_ranges = {
**BaseDatabaseOperations.integer_field_ranges,
'PositiveSmallIntegerField': (0, 65535),
'PositiveIntegerField': (0, 4294967295),
'PositiveBigIntegerField': (0, 18446744073709551615),
}
cast_data_types = {
'AutoField': 'signed integer',
'BigAutoField': 'signed integer',
'SmallAutoField': 'signed integer',
'CharField': 'char(%(max_length)s)',
'DecimalField': 'decimal(%(max_digits)s, %(decimal_places)s)',
'TextField': 'char',
'IntegerField': 'signed integer',
'BigIntegerField': 'signed integer',
'SmallIntegerField': 'signed integer',
'PositiveBigIntegerField': 'unsigned integer',
'PositiveIntegerField': 'unsigned integer',
'PositiveSmallIntegerField': 'unsigned integer',
}
cast_char_field_without_max_length = 'char'
explain_prefix = 'EXPLAIN'
def date_extract_sql(self, lookup_type, field_name):
# https://dev.mysql.com/doc/mysql/en/date-and-time-functions.html
if lookup_type == 'week_day':
# DAYOFWEEK() returns an integer, 1-7, Sunday=1.
return "DAYOFWEEK(%s)" % field_name
elif lookup_type == 'iso_week_day':
# WEEKDAY() returns an integer, 0-6, Monday=0.
return "WEEKDAY(%s) + 1" % field_name
elif lookup_type == 'week':
# Override the value of default_week_format for consistency with
# other database backends.
# Mode 3: Monday, 1-53, with 4 or more days this year.
return "WEEK(%s, 3)" % field_name
elif lookup_type == 'iso_year':
# Get the year part from the YEARWEEK function, which returns a
# number as year * 100 + week.
return "TRUNCATE(YEARWEEK(%s, 3), -2) / 100" % field_name
else:
# EXTRACT returns 1-53 based on ISO-8601 for the week number.
return "EXTRACT(%s FROM %s)" % (lookup_type.upper(), field_name)
def date_trunc_sql(self, lookup_type, field_name):
fields = {
'year': '%%Y-01-01',
'month': '%%Y-%%m-01',
} # Use double percents to escape.
if lookup_type in fields:
format_str = fields[lookup_type]
return "CAST(DATE_FORMAT(%s, '%s') AS DATE)" % (field_name, format_str)
elif lookup_type == 'quarter':
return "MAKEDATE(YEAR(%s), 1) + INTERVAL QUARTER(%s) QUARTER - INTERVAL 1 QUARTER" % (
field_name, field_name
)
elif lookup_type == 'week':
return "DATE_SUB(%s, INTERVAL WEEKDAY(%s) DAY)" % (
field_name, field_name
)
else:
return "DATE(%s)" % (field_name)
def _prepare_tzname_delta(self, tzname):
if '+' in tzname:
return tzname[tzname.find('+'):]
elif '-' in tzname:
return tzname[tzname.find('-'):]
return tzname
def _convert_field_to_tz(self, field_name, tzname):
if settings.USE_TZ and self.connection.timezone_name != tzname:
field_name = "CONVERT_TZ(%s, '%s', '%s')" % (
field_name,
self.connection.timezone_name,
self._prepare_tzname_delta(tzname),
)
return field_name
def datetime_cast_date_sql(self, field_name, tzname):
field_name = self._convert_field_to_tz(field_name, tzname)
return "DATE(%s)" % field_name
def datetime_cast_time_sql(self, field_name, tzname):
field_name = self._convert_field_to_tz(field_name, tzname)
return "TIME(%s)" % field_name
def datetime_extract_sql(self, lookup_type, field_name, tzname):
field_name = self._convert_field_to_tz(field_name, tzname)
return self.date_extract_sql(lookup_type, field_name)
def datetime_trunc_sql(self, lookup_type, field_name, tzname):
field_name = self._convert_field_to_tz(field_name, tzname)
fields = ['year', 'month', 'day', 'hour', 'minute', 'second']
format = ('%%Y-', '%%m', '-%%d', ' %%H:', '%%i', ':%%s') # Use double percents to escape.
format_def = ('0000-', '01', '-01', ' 00:', '00', ':00')
if lookup_type == 'quarter':
return (
"CAST(DATE_FORMAT(MAKEDATE(YEAR({field_name}), 1) + "
"INTERVAL QUARTER({field_name}) QUARTER - " +
"INTERVAL 1 QUARTER, '%%Y-%%m-01 00:00:00') AS DATETIME)"
).format(field_name=field_name)
if lookup_type == 'week':
return (
"CAST(DATE_FORMAT(DATE_SUB({field_name}, "
"INTERVAL WEEKDAY({field_name}) DAY), "
"'%%Y-%%m-%%d 00:00:00') AS DATETIME)"
).format(field_name=field_name)
try:
i = fields.index(lookup_type) + 1
except ValueError:
sql = field_name
else:
format_str = ''.join(format[:i] + format_def[i:])
sql = "CAST(DATE_FORMAT(%s, '%s') AS DATETIME)" % (field_name, format_str)
return sql
def time_trunc_sql(self, lookup_type, field_name):
fields = {
'hour': '%%H:00:00',
'minute': '%%H:%%i:00',
'second': '%%H:%%i:%%s',
} # Use double percents to escape.
if lookup_type in fields:
format_str = fields[lookup_type]
return "CAST(DATE_FORMAT(%s, '%s') AS TIME)" % (field_name, format_str)
else:
return "TIME(%s)" % (field_name)
def date_interval_sql(self, timedelta):
return 'INTERVAL %s MICROSECOND' % duration_microseconds(timedelta)
def fetch_returned_insert_rows(self, cursor):
"""
Given a cursor object that has just performed an INSERT...RETURNING
statement into a table, return the tuple of returned data.
"""
return cursor.fetchall()
def format_for_duration_arithmetic(self, sql):
return 'INTERVAL %s MICROSECOND' % sql
def force_no_ordering(self):
"""
"ORDER BY NULL" prevents MySQL from implicitly ordering by grouped
columns. If no ordering would otherwise be applied, we don't want any
implicit sorting going on.
"""
return [(None, ("NULL", [], False))]
def last_executed_query(self, cursor, sql, params):
# With MySQLdb, cursor objects have an (undocumented) "_executed"
# attribute where the exact query sent to the database is saved.
# See MySQLdb/cursors.py in the source distribution.
# MySQLdb returns string, PyMySQL bytes.
return force_str(getattr(cursor, '_executed', None), errors='replace')
def no_limit_value(self):
# 2**64 - 1, as recommended by the MySQL documentation
return 18446744073709551615
def quote_name(self, name):
if name.startswith("`") and name.endswith("`"):
return name # Quoting once is enough.
return "`%s`" % name
def random_function_sql(self):
return 'RAND()'
def return_insert_columns(self, fields):
# MySQL and MariaDB < 10.5.0 don't support an INSERT...RETURNING
# statement.
if not fields:
return '', ()
columns = [
'%s.%s' % (
self.quote_name(field.model._meta.db_table),
self.quote_name(field.column),
) for field in fields
]
return 'RETURNING %s' % ', '.join(columns), ()
def sql_flush(self, style, tables, *, reset_sequences=False, allow_cascade=False):
if not tables:
return []
sql = ['SET FOREIGN_KEY_CHECKS = 0;']
if reset_sequences:
# It's faster to TRUNCATE tables that require a sequence reset
# since ALTER TABLE AUTO_INCREMENT is slower than TRUNCATE.
sql.extend(
'%s %s;' % (
style.SQL_KEYWORD('TRUNCATE'),
style.SQL_FIELD(self.quote_name(table_name)),
) for table_name in tables
)
else:
# Otherwise issue a simple DELETE since it's faster than TRUNCATE
# and preserves sequences.
sql.extend(
'%s %s %s;' % (
style.SQL_KEYWORD('DELETE'),
style.SQL_KEYWORD('FROM'),
style.SQL_FIELD(self.quote_name(table_name)),
) for table_name in tables
)
sql.append('SET FOREIGN_KEY_CHECKS = 1;')
return sql
def sequence_reset_by_name_sql(self, style, sequences):
return [
'%s %s %s %s = 1;' % (
style.SQL_KEYWORD('ALTER'),
style.SQL_KEYWORD('TABLE'),
style.SQL_FIELD(self.quote_name(sequence_info['table'])),
style.SQL_FIELD('AUTO_INCREMENT'),
) for sequence_info in sequences
]
def validate_autopk_value(self, value):
# MySQLism: zero in AUTO_INCREMENT field does not work. Refs #17653.
if value == 0:
raise ValueError('The database backend does not accept 0 as a '
'value for AutoField.')
return value
def adapt_datetimefield_value(self, value):
if value is None:
return None
# Expression values are adapted by the database.
if hasattr(value, 'resolve_expression'):
return value
# MySQL doesn't support tz-aware datetimes
if timezone.is_aware(value):
if settings.USE_TZ:
value = timezone.make_naive(value, self.connection.timezone)
else:
raise ValueError("MySQL backend does not support timezone-aware datetimes when USE_TZ is False.")
return str(value)
def adapt_timefield_value(self, value):
if value is None:
return None
# Expression values are adapted by the database.
if hasattr(value, 'resolve_expression'):
return value
# MySQL doesn't support tz-aware times
if timezone.is_aware(value):
raise ValueError("MySQL backend does not support timezone-aware times.")
return str(value)
def max_name_length(self):
return 64
def bulk_insert_sql(self, fields, placeholder_rows):
placeholder_rows_sql = (", ".join(row) for row in placeholder_rows)
values_sql = ", ".join("(%s)" % sql for sql in placeholder_rows_sql)
return "VALUES " + values_sql
def combine_expression(self, connector, sub_expressions):
if connector == '^':
return 'POW(%s)' % ','.join(sub_expressions)
# Convert the result to a signed integer since MySQL's binary operators
# return an unsigned integer.
elif connector in ('&', '|', '<<', '#'):
connector = '^' if connector == '#' else connector
return 'CONVERT(%s, SIGNED)' % connector.join(sub_expressions)
elif connector == '>>':
lhs, rhs = sub_expressions
return 'FLOOR(%(lhs)s / POW(2, %(rhs)s))' % {'lhs': lhs, 'rhs': rhs}
return super().combine_expression(connector, sub_expressions)
def get_db_converters(self, expression):
converters = super().get_db_converters(expression)
internal_type = expression.output_field.get_internal_type()
if internal_type in ['BooleanField', 'NullBooleanField']:
converters.append(self.convert_booleanfield_value)
elif internal_type == 'DateTimeField':
if settings.USE_TZ:
converters.append(self.convert_datetimefield_value)
elif internal_type == 'UUIDField':
converters.append(self.convert_uuidfield_value)
return converters
def convert_booleanfield_value(self, value, expression, connection):
if value in (0, 1):
value = bool(value)
return value
def convert_datetimefield_value(self, value, expression, connection):
if value is not None:
value = timezone.make_aware(value, self.connection.timezone)
return value
def convert_uuidfield_value(self, value, expression, connection):
if value is not None:
value = uuid.UUID(value)
return value
def binary_placeholder_sql(self, value):
return '_binary %s' if value is not None and not hasattr(value, 'as_sql') else '%s'
def subtract_temporals(self, internal_type, lhs, rhs):
lhs_sql, lhs_params = lhs
rhs_sql, rhs_params = rhs
if internal_type == 'TimeField':
if self.connection.mysql_is_mariadb:
# MariaDB includes the microsecond component in TIME_TO_SEC as
# a decimal. MySQL returns an integer without microseconds.
return 'CAST((TIME_TO_SEC(%(lhs)s) - TIME_TO_SEC(%(rhs)s)) * 1000000 AS SIGNED)' % {
'lhs': lhs_sql, 'rhs': rhs_sql
}, (*lhs_params, *rhs_params)
return (
"((TIME_TO_SEC(%(lhs)s) * 1000000 + MICROSECOND(%(lhs)s)) -"
" (TIME_TO_SEC(%(rhs)s) * 1000000 + MICROSECOND(%(rhs)s)))"
) % {'lhs': lhs_sql, 'rhs': rhs_sql}, tuple(lhs_params) * 2 + tuple(rhs_params) * 2
params = (*rhs_params, *lhs_params)
return "TIMESTAMPDIFF(MICROSECOND, %s, %s)" % (rhs_sql, lhs_sql), params
def explain_query_prefix(self, format=None, **options):
# Alias MySQL's TRADITIONAL to TEXT for consistency with other backends.
if format and format.upper() == 'TEXT':
format = 'TRADITIONAL'
elif not format and 'TREE' in self.connection.features.supported_explain_formats:
# Use TREE by default (if supported) as it's more informative.
format = 'TREE'
analyze = options.pop('analyze', False)
prefix = super().explain_query_prefix(format, **options)
if analyze and self.connection.features.supports_explain_analyze:
# MariaDB uses ANALYZE instead of EXPLAIN ANALYZE.
prefix = 'ANALYZE' if self.connection.mysql_is_mariadb else prefix + ' ANALYZE'
if format and not (analyze and not self.connection.mysql_is_mariadb):
# Only MariaDB supports the analyze option with formats.
prefix += ' FORMAT=%s' % format
if self.connection.features.needs_explain_extended and not analyze and format is None:
# ANALYZE, EXTENDED, and FORMAT are mutually exclusive options.
prefix += ' EXTENDED'
return prefix
def regex_lookup(self, lookup_type):
# REGEXP BINARY doesn't work correctly in MySQL 8+ and REGEXP_LIKE
# doesn't exist in MySQL 5.6 or in MariaDB.
if self.connection.mysql_version < (8, 0, 0) or self.connection.mysql_is_mariadb:
if lookup_type == 'regex':
return '%s REGEXP BINARY %s'
return '%s REGEXP %s'
match_option = 'c' if lookup_type == 'regex' else 'i'
return "REGEXP_LIKE(%%s, %%s, '%s')" % match_option
def insert_statement(self, ignore_conflicts=False):
return 'INSERT IGNORE INTO' if ignore_conflicts else super().insert_statement(ignore_conflicts)
def lookup_cast(self, lookup_type, internal_type=None):
lookup = '%s'
if internal_type == 'JSONField':
if self.connection.mysql_is_mariadb or lookup_type in (
'iexact', 'contains', 'icontains', 'startswith', 'istartswith',
'endswith', 'iendswith', 'regex', 'iregex',
):
lookup = 'JSON_UNQUOTE(%s)'
return lookup
|
f23125d1e1f3eaee2a794bec26413d8d1a39f21d5afc6b8b2b6ee7cbb844b7af | from django.db.backends.base.schema import BaseDatabaseSchemaEditor
from django.db.models import NOT_PROVIDED
class DatabaseSchemaEditor(BaseDatabaseSchemaEditor):
sql_rename_table = "RENAME TABLE %(old_table)s TO %(new_table)s"
sql_alter_column_null = "MODIFY %(column)s %(type)s NULL"
sql_alter_column_not_null = "MODIFY %(column)s %(type)s NOT NULL"
sql_alter_column_type = "MODIFY %(column)s %(type)s"
# No 'CASCADE' which works as a no-op in MySQL but is undocumented
sql_delete_column = "ALTER TABLE %(table)s DROP COLUMN %(column)s"
sql_delete_unique = "ALTER TABLE %(table)s DROP INDEX %(name)s"
sql_create_column_inline_fk = (
', ADD CONSTRAINT %(name)s FOREIGN KEY (%(column)s) '
'REFERENCES %(to_table)s(%(to_column)s)'
)
sql_delete_fk = "ALTER TABLE %(table)s DROP FOREIGN KEY %(name)s"
sql_delete_index = "DROP INDEX %(name)s ON %(table)s"
sql_create_pk = "ALTER TABLE %(table)s ADD CONSTRAINT %(name)s PRIMARY KEY (%(columns)s)"
sql_delete_pk = "ALTER TABLE %(table)s DROP PRIMARY KEY"
sql_create_index = 'CREATE INDEX %(name)s ON %(table)s (%(columns)s)%(extra)s'
@property
def sql_delete_check(self):
if self.connection.mysql_is_mariadb:
# The name of the column check constraint is the same as the field
# name on MariaDB. Adding IF EXISTS clause prevents migrations
# crash. Constraint is removed during a "MODIFY" column statement.
return 'ALTER TABLE %(table)s DROP CONSTRAINT IF EXISTS %(name)s'
return 'ALTER TABLE %(table)s DROP CHECK %(name)s'
@property
def sql_rename_column(self):
# MariaDB >= 10.5.2 and MySQL >= 8.0.4 support an
# "ALTER TABLE ... RENAME COLUMN" statement.
if self.connection.mysql_is_mariadb:
if self.connection.mysql_version >= (10, 5, 2):
return super().sql_rename_column
elif self.connection.mysql_version >= (8, 0, 4):
return super().sql_rename_column
return 'ALTER TABLE %(table)s CHANGE %(old_column)s %(new_column)s %(type)s'
def quote_value(self, value):
self.connection.ensure_connection()
if isinstance(value, str):
value = value.replace('%', '%%')
# MySQLdb escapes to string, PyMySQL to bytes.
quoted = self.connection.connection.escape(value, self.connection.connection.encoders)
if isinstance(value, str) and isinstance(quoted, bytes):
quoted = quoted.decode()
return quoted
def _is_limited_data_type(self, field):
db_type = field.db_type(self.connection)
return db_type is not None and db_type.lower() in self.connection._limited_data_types
def skip_default(self, field):
if not self._supports_limited_data_type_defaults:
return self._is_limited_data_type(field)
return False
@property
def _supports_limited_data_type_defaults(self):
# MariaDB >= 10.2.1 and MySQL >= 8.0.13 supports defaults for BLOB
# and TEXT.
if self.connection.mysql_is_mariadb:
return self.connection.mysql_version >= (10, 2, 1)
return self.connection.mysql_version >= (8, 0, 13)
def _column_default_sql(self, field):
if (
not self.connection.mysql_is_mariadb and
self._supports_limited_data_type_defaults and
self._is_limited_data_type(field)
):
# MySQL supports defaults for BLOB and TEXT columns only if the
# default value is written as an expression i.e. in parentheses.
return '(%s)'
return super()._column_default_sql(field)
def add_field(self, model, field):
super().add_field(model, field)
# Simulate the effect of a one-off default.
# field.default may be unhashable, so a set isn't used for "in" check.
if self.skip_default(field) and field.default not in (None, NOT_PROVIDED):
effective_default = self.effective_default(field)
self.execute('UPDATE %(table)s SET %(column)s = %%s' % {
'table': self.quote_name(model._meta.db_table),
'column': self.quote_name(field.column),
}, [effective_default])
def _field_should_be_indexed(self, model, field):
create_index = super()._field_should_be_indexed(model, field)
storage = self.connection.introspection.get_storage_engine(
self.connection.cursor(), model._meta.db_table
)
# No need to create an index for ForeignKey fields except if
# db_constraint=False because the index from that constraint won't be
# created.
if (storage == "InnoDB" and
create_index and
field.get_internal_type() == 'ForeignKey' and
field.db_constraint):
return False
return not self._is_limited_data_type(field) and create_index
def _delete_composed_index(self, model, fields, *args):
"""
MySQL can remove an implicit FK index on a field when that field is
covered by another index like a unique_together. "covered" here means
that the more complex index starts like the simpler one.
http://bugs.mysql.com/bug.php?id=37910 / Django ticket #24757
We check here before removing the [unique|index]_together if we have to
recreate a FK index.
"""
first_field = model._meta.get_field(fields[0])
if first_field.get_internal_type() == 'ForeignKey':
constraint_names = self._constraint_names(model, [first_field.column], index=True)
if not constraint_names:
self.execute(self._create_index_sql(model, [first_field], suffix=""))
return super()._delete_composed_index(model, fields, *args)
def _set_field_new_type_null_status(self, field, new_type):
"""
Keep the null property of the old field. If it has changed, it will be
handled separately.
"""
if field.null:
new_type += " NULL"
else:
new_type += " NOT NULL"
return new_type
def _alter_column_type_sql(self, model, old_field, new_field, new_type):
new_type = self._set_field_new_type_null_status(old_field, new_type)
return super()._alter_column_type_sql(model, old_field, new_field, new_type)
def _rename_field_sql(self, table, old_field, new_field, new_type):
new_type = self._set_field_new_type_null_status(old_field, new_type)
return super()._rename_field_sql(table, old_field, new_field, new_type)
|
08cef97070d7abd9b0e38022800406368b2bcd15daebcbfe8a4a963df4e49550 | import subprocess
from django.db.backends.base.client import BaseDatabaseClient
class DatabaseClient(BaseDatabaseClient):
executable_name = 'mysql'
@classmethod
def settings_to_cmd_args(cls, settings_dict, parameters):
args = [cls.executable_name]
db = settings_dict['OPTIONS'].get('db', settings_dict['NAME'])
user = settings_dict['OPTIONS'].get('user', settings_dict['USER'])
passwd = settings_dict['OPTIONS'].get('passwd', settings_dict['PASSWORD'])
host = settings_dict['OPTIONS'].get('host', settings_dict['HOST'])
port = settings_dict['OPTIONS'].get('port', settings_dict['PORT'])
server_ca = settings_dict['OPTIONS'].get('ssl', {}).get('ca')
client_cert = settings_dict['OPTIONS'].get('ssl', {}).get('cert')
client_key = settings_dict['OPTIONS'].get('ssl', {}).get('key')
defaults_file = settings_dict['OPTIONS'].get('read_default_file')
# Seems to be no good way to set sql_mode with CLI.
if defaults_file:
args += ["--defaults-file=%s" % defaults_file]
if user:
args += ["--user=%s" % user]
if passwd:
args += ["--password=%s" % passwd]
if host:
if '/' in host:
args += ["--socket=%s" % host]
else:
args += ["--host=%s" % host]
if port:
args += ["--port=%s" % port]
if server_ca:
args += ["--ssl-ca=%s" % server_ca]
if client_cert:
args += ["--ssl-cert=%s" % client_cert]
if client_key:
args += ["--ssl-key=%s" % client_key]
if db:
args += [db]
args.extend(parameters)
return args
def runshell(self, parameters):
args = DatabaseClient.settings_to_cmd_args(self.connection.settings_dict, parameters)
subprocess.run(args, check=True)
|
da21f8528f4a254689b35d99216117407797666c64a73908bd8fb1fdd1893996 | import subprocess
import sys
from django.db.backends.base.creation import BaseDatabaseCreation
from .client import DatabaseClient
class DatabaseCreation(BaseDatabaseCreation):
def sql_table_creation_suffix(self):
suffix = []
test_settings = self.connection.settings_dict['TEST']
if test_settings['CHARSET']:
suffix.append('CHARACTER SET %s' % test_settings['CHARSET'])
if test_settings['COLLATION']:
suffix.append('COLLATE %s' % test_settings['COLLATION'])
return ' '.join(suffix)
def _execute_create_test_db(self, cursor, parameters, keepdb=False):
try:
super()._execute_create_test_db(cursor, parameters, keepdb)
except Exception as e:
if len(e.args) < 1 or e.args[0] != 1007:
# All errors except "database exists" (1007) cancel tests.
self.log('Got an error creating the test database: %s' % e)
sys.exit(2)
else:
raise
def _clone_test_db(self, suffix, verbosity, keepdb=False):
source_database_name = self.connection.settings_dict['NAME']
target_database_name = self.get_test_db_clone_settings(suffix)['NAME']
test_db_params = {
'dbname': self.connection.ops.quote_name(target_database_name),
'suffix': self.sql_table_creation_suffix(),
}
with self._nodb_cursor() as cursor:
try:
self._execute_create_test_db(cursor, test_db_params, keepdb)
except Exception:
if keepdb:
# If the database should be kept, skip everything else.
return
try:
if verbosity >= 1:
self.log('Destroying old test database for alias %s...' % (
self._get_database_display_str(verbosity, target_database_name),
))
cursor.execute('DROP DATABASE %(dbname)s' % test_db_params)
self._execute_create_test_db(cursor, test_db_params, keepdb)
except Exception as e:
self.log('Got an error recreating the test database: %s' % e)
sys.exit(2)
self._clone_db(source_database_name, target_database_name)
def _clone_db(self, source_database_name, target_database_name):
dump_args = DatabaseClient.settings_to_cmd_args(self.connection.settings_dict, [])[1:]
dump_cmd = ['mysqldump', *dump_args[:-1], '--routines', '--events', source_database_name]
load_cmd = DatabaseClient.settings_to_cmd_args(self.connection.settings_dict, [])
load_cmd[-1] = target_database_name
with subprocess.Popen(dump_cmd, stdout=subprocess.PIPE) as dump_proc:
with subprocess.Popen(load_cmd, stdin=dump_proc.stdout, stdout=subprocess.DEVNULL):
# Allow dump_proc to receive a SIGPIPE if the load process exits.
dump_proc.stdout.close()
|
f94d538998a74bd5fdadc8b929b835e77f7e7dff749bea9f80d20b896be85bdf | import operator
from django.db import InterfaceError
from django.db.backends.base.features import BaseDatabaseFeatures
from django.utils.functional import cached_property
class DatabaseFeatures(BaseDatabaseFeatures):
allows_group_by_selected_pks = True
can_return_columns_from_insert = True
can_return_rows_from_bulk_insert = True
has_real_datatype = True
has_native_uuid_field = True
has_native_duration_field = True
has_native_json_field = True
can_defer_constraint_checks = True
has_select_for_update = True
has_select_for_update_nowait = True
has_select_for_update_of = True
has_select_for_update_skip_locked = True
can_release_savepoints = True
supports_tablespaces = True
supports_transactions = True
can_introspect_autofield = True
can_introspect_ip_address_field = True
can_introspect_materialized_views = True
can_introspect_small_integer_field = True
can_distinct_on_fields = True
can_rollback_ddl = True
supports_combined_alters = True
nulls_order_largest = True
closed_cursor_error_class = InterfaceError
has_case_insensitive_like = False
greatest_least_ignores_nulls = True
can_clone_databases = True
supports_temporal_subtraction = True
supports_slicing_ordering_in_compound = True
create_test_procedure_without_params_sql = """
CREATE FUNCTION test_procedure () RETURNS void AS $$
DECLARE
V_I INTEGER;
BEGIN
V_I := 1;
END;
$$ LANGUAGE plpgsql;"""
create_test_procedure_with_int_param_sql = """
CREATE FUNCTION test_procedure (P_I INTEGER) RETURNS void AS $$
DECLARE
V_I INTEGER;
BEGIN
V_I := P_I;
END;
$$ LANGUAGE plpgsql;"""
requires_casted_case_in_updates = True
supports_over_clause = True
only_supports_unbounded_with_preceding_and_following = True
supports_aggregate_filter_clause = True
supported_explain_formats = {'JSON', 'TEXT', 'XML', 'YAML'}
validates_explain_options = False # A query will error on invalid options.
supports_deferrable_unique_constraints = True
@cached_property
def is_postgresql_9_6(self):
return self.connection.pg_version >= 90600
@cached_property
def is_postgresql_10(self):
return self.connection.pg_version >= 100000
@cached_property
def is_postgresql_11(self):
return self.connection.pg_version >= 110000
@cached_property
def is_postgresql_12(self):
return self.connection.pg_version >= 120000
has_bloom_index = property(operator.attrgetter('is_postgresql_9_6'))
has_brin_autosummarize = property(operator.attrgetter('is_postgresql_10'))
has_phraseto_tsquery = property(operator.attrgetter('is_postgresql_9_6'))
has_websearch_to_tsquery = property(operator.attrgetter('is_postgresql_11'))
supports_table_partitions = property(operator.attrgetter('is_postgresql_10'))
|
f9c32ecf00429bd3fdf97ef071a5abe54904c632850512dcce0ca082eae52ab8 | from django.db.backends.base.introspection import (
BaseDatabaseIntrospection, FieldInfo, TableInfo,
)
from django.db.models import Index
class DatabaseIntrospection(BaseDatabaseIntrospection):
# Maps type codes to Django Field types.
data_types_reverse = {
16: 'BooleanField',
17: 'BinaryField',
20: 'BigIntegerField',
21: 'SmallIntegerField',
23: 'IntegerField',
25: 'TextField',
700: 'FloatField',
701: 'FloatField',
869: 'GenericIPAddressField',
1042: 'CharField', # blank-padded
1043: 'CharField',
1082: 'DateField',
1083: 'TimeField',
1114: 'DateTimeField',
1184: 'DateTimeField',
1186: 'DurationField',
1266: 'TimeField',
1700: 'DecimalField',
2950: 'UUIDField',
3802: 'JSONField',
}
ignored_tables = []
def get_field_type(self, data_type, description):
field_type = super().get_field_type(data_type, description)
if description.default and 'nextval' in description.default:
if field_type == 'IntegerField':
return 'AutoField'
elif field_type == 'BigIntegerField':
return 'BigAutoField'
elif field_type == 'SmallIntegerField':
return 'SmallAutoField'
return field_type
def get_table_list(self, cursor):
"""Return a list of table and view names in the current database."""
cursor.execute("""
SELECT c.relname,
CASE WHEN {} THEN 'p' WHEN c.relkind IN ('m', 'v') THEN 'v' ELSE 't' END
FROM pg_catalog.pg_class c
LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHERE c.relkind IN ('f', 'm', 'p', 'r', 'v')
AND n.nspname NOT IN ('pg_catalog', 'pg_toast')
AND pg_catalog.pg_table_is_visible(c.oid)
""".format('c.relispartition' if self.connection.features.supports_table_partitions else 'FALSE'))
return [TableInfo(*row) for row in cursor.fetchall() if row[0] not in self.ignored_tables]
def get_table_description(self, cursor, table_name):
"""
Return a description of the table with the DB-API cursor.description
interface.
"""
# Query the pg_catalog tables as cursor.description does not reliably
# return the nullable property and information_schema.columns does not
# contain details of materialized views.
cursor.execute("""
SELECT
a.attname AS column_name,
NOT (a.attnotnull OR (t.typtype = 'd' AND t.typnotnull)) AS is_nullable,
pg_get_expr(ad.adbin, ad.adrelid) AS column_default
FROM pg_attribute a
LEFT JOIN pg_attrdef ad ON a.attrelid = ad.adrelid AND a.attnum = ad.adnum
JOIN pg_type t ON a.atttypid = t.oid
JOIN pg_class c ON a.attrelid = c.oid
JOIN pg_namespace n ON c.relnamespace = n.oid
WHERE c.relkind IN ('f', 'm', 'p', 'r', 'v')
AND c.relname = %s
AND n.nspname NOT IN ('pg_catalog', 'pg_toast')
AND pg_catalog.pg_table_is_visible(c.oid)
""", [table_name])
field_map = {line[0]: line[1:] for line in cursor.fetchall()}
cursor.execute("SELECT * FROM %s LIMIT 1" % self.connection.ops.quote_name(table_name))
return [
FieldInfo(
line.name,
line.type_code,
line.display_size,
line.internal_size,
line.precision,
line.scale,
*field_map[line.name],
)
for line in cursor.description
]
def get_sequences(self, cursor, table_name, table_fields=()):
cursor.execute("""
SELECT s.relname as sequence_name, col.attname
FROM pg_class s
JOIN pg_namespace sn ON sn.oid = s.relnamespace
JOIN pg_depend d ON d.refobjid = s.oid AND d.refclassid = 'pg_class'::regclass
JOIN pg_attrdef ad ON ad.oid = d.objid AND d.classid = 'pg_attrdef'::regclass
JOIN pg_attribute col ON col.attrelid = ad.adrelid AND col.attnum = ad.adnum
JOIN pg_class tbl ON tbl.oid = ad.adrelid
WHERE s.relkind = 'S'
AND d.deptype in ('a', 'n')
AND pg_catalog.pg_table_is_visible(tbl.oid)
AND tbl.relname = %s
""", [table_name])
return [
{'name': row[0], 'table': table_name, 'column': row[1]}
for row in cursor.fetchall()
]
def get_relations(self, cursor, table_name):
"""
Return a dictionary of {field_name: (field_name_other_table, other_table)}
representing all relationships to the given table.
"""
return {row[0]: (row[2], row[1]) for row in self.get_key_columns(cursor, table_name)}
def get_key_columns(self, cursor, table_name):
cursor.execute("""
SELECT a1.attname, c2.relname, a2.attname
FROM pg_constraint con
LEFT JOIN pg_class c1 ON con.conrelid = c1.oid
LEFT JOIN pg_class c2 ON con.confrelid = c2.oid
LEFT JOIN pg_attribute a1 ON c1.oid = a1.attrelid AND a1.attnum = con.conkey[1]
LEFT JOIN pg_attribute a2 ON c2.oid = a2.attrelid AND a2.attnum = con.confkey[1]
WHERE
c1.relname = %s AND
con.contype = 'f' AND
c1.relnamespace = c2.relnamespace AND
pg_catalog.pg_table_is_visible(c1.oid)
""", [table_name])
return cursor.fetchall()
def get_constraints(self, cursor, table_name):
"""
Retrieve any constraints or keys (unique, pk, fk, check, index) across
one or more columns. Also retrieve the definition of expression-based
indexes.
"""
constraints = {}
# Loop over the key table, collecting things as constraints. The column
# array must return column names in the same order in which they were
# created.
cursor.execute("""
SELECT
c.conname,
array(
SELECT attname
FROM unnest(c.conkey) WITH ORDINALITY cols(colid, arridx)
JOIN pg_attribute AS ca ON cols.colid = ca.attnum
WHERE ca.attrelid = c.conrelid
ORDER BY cols.arridx
),
c.contype,
(SELECT fkc.relname || '.' || fka.attname
FROM pg_attribute AS fka
JOIN pg_class AS fkc ON fka.attrelid = fkc.oid
WHERE fka.attrelid = c.confrelid AND fka.attnum = c.confkey[1]),
cl.reloptions
FROM pg_constraint AS c
JOIN pg_class AS cl ON c.conrelid = cl.oid
WHERE cl.relname = %s AND pg_catalog.pg_table_is_visible(cl.oid)
""", [table_name])
for constraint, columns, kind, used_cols, options in cursor.fetchall():
constraints[constraint] = {
"columns": columns,
"primary_key": kind == "p",
"unique": kind in ["p", "u"],
"foreign_key": tuple(used_cols.split(".", 1)) if kind == "f" else None,
"check": kind == "c",
"index": False,
"definition": None,
"options": options,
}
# Now get indexes
cursor.execute("""
SELECT
indexname, array_agg(attname ORDER BY arridx), indisunique, indisprimary,
array_agg(ordering ORDER BY arridx), amname, exprdef, s2.attoptions
FROM (
SELECT
c2.relname as indexname, idx.*, attr.attname, am.amname,
CASE
WHEN idx.indexprs IS NOT NULL THEN
pg_get_indexdef(idx.indexrelid)
END AS exprdef,
CASE am.amname
WHEN 'btree' THEN
CASE (option & 1)
WHEN 1 THEN 'DESC' ELSE 'ASC'
END
END as ordering,
c2.reloptions as attoptions
FROM (
SELECT *
FROM pg_index i, unnest(i.indkey, i.indoption) WITH ORDINALITY koi(key, option, arridx)
) idx
LEFT JOIN pg_class c ON idx.indrelid = c.oid
LEFT JOIN pg_class c2 ON idx.indexrelid = c2.oid
LEFT JOIN pg_am am ON c2.relam = am.oid
LEFT JOIN pg_attribute attr ON attr.attrelid = c.oid AND attr.attnum = idx.key
WHERE c.relname = %s AND pg_catalog.pg_table_is_visible(c.oid)
) s2
GROUP BY indexname, indisunique, indisprimary, amname, exprdef, attoptions;
""", [table_name])
for index, columns, unique, primary, orders, type_, definition, options in cursor.fetchall():
if index not in constraints:
basic_index = type_ == 'btree' and not index.endswith('_btree') and options is None
constraints[index] = {
"columns": columns if columns != [None] else [],
"orders": orders if orders != [None] else [],
"primary_key": primary,
"unique": unique,
"foreign_key": None,
"check": False,
"index": True,
"type": Index.suffix if basic_index else type_,
"definition": definition,
"options": options,
}
return constraints
|
b8dc5d2853541c1c241b29bb4b5c9b53ceee2c531d18b07b5904c6f504fa375c | """
PostgreSQL database backend for Django.
Requires psycopg 2: https://www.psycopg.org/
"""
import asyncio
import threading
import warnings
from contextlib import contextmanager
from django.conf import settings
from django.core.exceptions import ImproperlyConfigured
from django.db import DatabaseError as WrappedDatabaseError, connections
from django.db.backends.base.base import BaseDatabaseWrapper
from django.db.backends.utils import (
CursorDebugWrapper as BaseCursorDebugWrapper,
)
from django.utils.asyncio import async_unsafe
from django.utils.functional import cached_property
from django.utils.safestring import SafeString
from django.utils.version import get_version_tuple
try:
import psycopg2 as Database
import psycopg2.extensions
import psycopg2.extras
except ImportError as e:
raise ImproperlyConfigured("Error loading psycopg2 module: %s" % e)
def psycopg2_version():
version = psycopg2.__version__.split(' ', 1)[0]
return get_version_tuple(version)
PSYCOPG2_VERSION = psycopg2_version()
if PSYCOPG2_VERSION < (2, 5, 4):
raise ImproperlyConfigured("psycopg2_version 2.5.4 or newer is required; you have %s" % psycopg2.__version__)
# Some of these import psycopg2, so import them after checking if it's installed.
from .client import DatabaseClient # NOQA isort:skip
from .creation import DatabaseCreation # NOQA isort:skip
from .features import DatabaseFeatures # NOQA isort:skip
from .introspection import DatabaseIntrospection # NOQA isort:skip
from .operations import DatabaseOperations # NOQA isort:skip
from .schema import DatabaseSchemaEditor # NOQA isort:skip
psycopg2.extensions.register_adapter(SafeString, psycopg2.extensions.QuotedString)
psycopg2.extras.register_uuid()
# Register support for inet[] manually so we don't have to handle the Inet()
# object on load all the time.
INETARRAY_OID = 1041
INETARRAY = psycopg2.extensions.new_array_type(
(INETARRAY_OID,),
'INETARRAY',
psycopg2.extensions.UNICODE,
)
psycopg2.extensions.register_type(INETARRAY)
class DatabaseWrapper(BaseDatabaseWrapper):
vendor = 'postgresql'
display_name = 'PostgreSQL'
# This dictionary maps Field objects to their associated PostgreSQL column
# types, as strings. Column-type strings can contain format strings; they'll
# be interpolated against the values of Field.__dict__ before being output.
# If a column type is set to None, it won't be included in the output.
data_types = {
'AutoField': 'serial',
'BigAutoField': 'bigserial',
'BinaryField': 'bytea',
'BooleanField': 'boolean',
'CharField': 'varchar(%(max_length)s)',
'DateField': 'date',
'DateTimeField': 'timestamp with time zone',
'DecimalField': 'numeric(%(max_digits)s, %(decimal_places)s)',
'DurationField': 'interval',
'FileField': 'varchar(%(max_length)s)',
'FilePathField': 'varchar(%(max_length)s)',
'FloatField': 'double precision',
'IntegerField': 'integer',
'BigIntegerField': 'bigint',
'IPAddressField': 'inet',
'GenericIPAddressField': 'inet',
'JSONField': 'jsonb',
'NullBooleanField': 'boolean',
'OneToOneField': 'integer',
'PositiveBigIntegerField': 'bigint',
'PositiveIntegerField': 'integer',
'PositiveSmallIntegerField': 'smallint',
'SlugField': 'varchar(%(max_length)s)',
'SmallAutoField': 'smallserial',
'SmallIntegerField': 'smallint',
'TextField': 'text',
'TimeField': 'time',
'UUIDField': 'uuid',
}
data_type_check_constraints = {
'PositiveBigIntegerField': '"%(column)s" >= 0',
'PositiveIntegerField': '"%(column)s" >= 0',
'PositiveSmallIntegerField': '"%(column)s" >= 0',
}
operators = {
'exact': '= %s',
'iexact': '= UPPER(%s)',
'contains': 'LIKE %s',
'icontains': 'LIKE UPPER(%s)',
'regex': '~ %s',
'iregex': '~* %s',
'gt': '> %s',
'gte': '>= %s',
'lt': '< %s',
'lte': '<= %s',
'startswith': 'LIKE %s',
'endswith': 'LIKE %s',
'istartswith': 'LIKE UPPER(%s)',
'iendswith': 'LIKE UPPER(%s)',
}
# The patterns below are used to generate SQL pattern lookup clauses when
# the right-hand side of the lookup isn't a raw string (it might be an expression
# or the result of a bilateral transformation).
# In those cases, special characters for LIKE operators (e.g. \, *, _) should be
# escaped on database side.
#
# Note: we use str.format() here for readability as '%' is used as a wildcard for
# the LIKE operator.
pattern_esc = r"REPLACE(REPLACE(REPLACE({}, E'\\', E'\\\\'), E'%%', E'\\%%'), E'_', E'\\_')"
pattern_ops = {
'contains': "LIKE '%%' || {} || '%%'",
'icontains': "LIKE '%%' || UPPER({}) || '%%'",
'startswith': "LIKE {} || '%%'",
'istartswith': "LIKE UPPER({}) || '%%'",
'endswith': "LIKE '%%' || {}",
'iendswith': "LIKE '%%' || UPPER({})",
}
Database = Database
SchemaEditorClass = DatabaseSchemaEditor
# Classes instantiated in __init__().
client_class = DatabaseClient
creation_class = DatabaseCreation
features_class = DatabaseFeatures
introspection_class = DatabaseIntrospection
ops_class = DatabaseOperations
# PostgreSQL backend-specific attributes.
_named_cursor_idx = 0
def get_connection_params(self):
settings_dict = self.settings_dict
# None may be used to connect to the default 'postgres' db
if settings_dict['NAME'] == '':
raise ImproperlyConfigured(
"settings.DATABASES is improperly configured. "
"Please supply the NAME value.")
if len(settings_dict['NAME'] or '') > self.ops.max_name_length():
raise ImproperlyConfigured(
"The database name '%s' (%d characters) is longer than "
"PostgreSQL's limit of %d characters. Supply a shorter NAME "
"in settings.DATABASES." % (
settings_dict['NAME'],
len(settings_dict['NAME']),
self.ops.max_name_length(),
)
)
conn_params = {
'database': settings_dict['NAME'] or 'postgres',
**settings_dict['OPTIONS'],
}
conn_params.pop('isolation_level', None)
if settings_dict['USER']:
conn_params['user'] = settings_dict['USER']
if settings_dict['PASSWORD']:
conn_params['password'] = settings_dict['PASSWORD']
if settings_dict['HOST']:
conn_params['host'] = settings_dict['HOST']
if settings_dict['PORT']:
conn_params['port'] = settings_dict['PORT']
return conn_params
@async_unsafe
def get_new_connection(self, conn_params):
connection = Database.connect(**conn_params)
# self.isolation_level must be set:
# - after connecting to the database in order to obtain the database's
# default when no value is explicitly specified in options.
# - before calling _set_autocommit() because if autocommit is on, that
# will set connection.isolation_level to ISOLATION_LEVEL_AUTOCOMMIT.
options = self.settings_dict['OPTIONS']
try:
self.isolation_level = options['isolation_level']
except KeyError:
self.isolation_level = connection.isolation_level
else:
# Set the isolation level to the value from OPTIONS.
if self.isolation_level != connection.isolation_level:
connection.set_session(isolation_level=self.isolation_level)
return connection
def ensure_timezone(self):
if self.connection is None:
return False
conn_timezone_name = self.connection.get_parameter_status('TimeZone')
timezone_name = self.timezone_name
if timezone_name and conn_timezone_name != timezone_name:
with self.connection.cursor() as cursor:
cursor.execute(self.ops.set_time_zone_sql(), [timezone_name])
return True
return False
def init_connection_state(self):
self.connection.set_client_encoding('UTF8')
timezone_changed = self.ensure_timezone()
if timezone_changed:
# Commit after setting the time zone (see #17062)
if not self.get_autocommit():
self.connection.commit()
@async_unsafe
def create_cursor(self, name=None):
if name:
# In autocommit mode, the cursor will be used outside of a
# transaction, hence use a holdable cursor.
cursor = self.connection.cursor(name, scrollable=False, withhold=self.connection.autocommit)
else:
cursor = self.connection.cursor()
cursor.tzinfo_factory = self.tzinfo_factory if settings.USE_TZ else None
return cursor
def tzinfo_factory(self, offset):
return self.timezone
@async_unsafe
def chunked_cursor(self):
self._named_cursor_idx += 1
# Get the current async task
# Note that right now this is behind @async_unsafe, so this is
# unreachable, but in future we'll start loosening this restriction.
# For now, it's here so that every use of "threading" is
# also async-compatible.
try:
if hasattr(asyncio, 'current_task'):
# Python 3.7 and up
current_task = asyncio.current_task()
else:
# Python 3.6
current_task = asyncio.Task.current_task()
except RuntimeError:
current_task = None
# Current task can be none even if the current_task call didn't error
if current_task:
task_ident = str(id(current_task))
else:
task_ident = 'sync'
# Use that and the thread ident to get a unique name
return self._cursor(
name='_django_curs_%d_%s_%d' % (
# Avoid reusing name in other threads / tasks
threading.current_thread().ident,
task_ident,
self._named_cursor_idx,
)
)
def _set_autocommit(self, autocommit):
with self.wrap_database_errors:
self.connection.autocommit = autocommit
def check_constraints(self, table_names=None):
"""
Check constraints by setting them to immediate. Return them to deferred
afterward.
"""
with self.cursor() as cursor:
cursor.execute('SET CONSTRAINTS ALL IMMEDIATE')
cursor.execute('SET CONSTRAINTS ALL DEFERRED')
def is_usable(self):
try:
# Use a psycopg cursor directly, bypassing Django's utilities.
with self.connection.cursor() as cursor:
cursor.execute('SELECT 1')
except Database.Error:
return False
else:
return True
@contextmanager
def _nodb_cursor(self):
try:
with super()._nodb_cursor() as cursor:
yield cursor
except (Database.DatabaseError, WrappedDatabaseError):
warnings.warn(
"Normally Django will use a connection to the 'postgres' database "
"to avoid running initialization queries against the production "
"database when it's not needed (for example, when running tests). "
"Django was unable to create a connection to the 'postgres' database "
"and will use the first PostgreSQL database instead.",
RuntimeWarning
)
for connection in connections.all():
if connection.vendor == 'postgresql' and connection.settings_dict['NAME'] != 'postgres':
conn = self.__class__(
{**self.settings_dict, 'NAME': connection.settings_dict['NAME']},
alias=self.alias,
)
try:
with conn.cursor() as cursor:
yield cursor
finally:
conn.close()
@cached_property
def pg_version(self):
with self.temporary_connection():
return self.connection.server_version
def make_debug_cursor(self, cursor):
return CursorDebugWrapper(cursor, self)
class CursorDebugWrapper(BaseCursorDebugWrapper):
def copy_expert(self, sql, file, *args):
with self.debug_sql(sql):
return self.cursor.copy_expert(sql, file, *args)
def copy_to(self, file, table, *args, **kwargs):
with self.debug_sql(sql='COPY %s TO STDOUT' % table):
return self.cursor.copy_to(file, table, *args, **kwargs)
|
f02b3f493e82f648aead9c4bee309aaf9bcb8c062cc4f26b0a53eb455e218909 | from psycopg2.extras import Inet
from django.conf import settings
from django.db.backends.base.operations import BaseDatabaseOperations
class DatabaseOperations(BaseDatabaseOperations):
cast_char_field_without_max_length = 'varchar'
explain_prefix = 'EXPLAIN'
cast_data_types = {
'AutoField': 'integer',
'BigAutoField': 'bigint',
'SmallAutoField': 'smallint',
}
def unification_cast_sql(self, output_field):
internal_type = output_field.get_internal_type()
if internal_type in ("GenericIPAddressField", "IPAddressField", "TimeField", "UUIDField"):
# PostgreSQL will resolve a union as type 'text' if input types are
# 'unknown'.
# https://www.postgresql.org/docs/current/typeconv-union-case.html
# These fields cannot be implicitly cast back in the default
# PostgreSQL configuration so we need to explicitly cast them.
# We must also remove components of the type within brackets:
# varchar(255) -> varchar.
return 'CAST(%%s AS %s)' % output_field.db_type(self.connection).split('(')[0]
return '%s'
def date_extract_sql(self, lookup_type, field_name):
# https://www.postgresql.org/docs/current/functions-datetime.html#FUNCTIONS-DATETIME-EXTRACT
if lookup_type == 'week_day':
# For consistency across backends, we return Sunday=1, Saturday=7.
return "EXTRACT('dow' FROM %s) + 1" % field_name
elif lookup_type == 'iso_week_day':
return "EXTRACT('isodow' FROM %s)" % field_name
elif lookup_type == 'iso_year':
return "EXTRACT('isoyear' FROM %s)" % field_name
else:
return "EXTRACT('%s' FROM %s)" % (lookup_type, field_name)
def date_trunc_sql(self, lookup_type, field_name):
# https://www.postgresql.org/docs/current/functions-datetime.html#FUNCTIONS-DATETIME-TRUNC
return "DATE_TRUNC('%s', %s)" % (lookup_type, field_name)
def _prepare_tzname_delta(self, tzname):
if '+' in tzname:
return tzname.replace('+', '-')
elif '-' in tzname:
return tzname.replace('-', '+')
return tzname
def _convert_field_to_tz(self, field_name, tzname):
if settings.USE_TZ:
field_name = "%s AT TIME ZONE '%s'" % (field_name, self._prepare_tzname_delta(tzname))
return field_name
def datetime_cast_date_sql(self, field_name, tzname):
field_name = self._convert_field_to_tz(field_name, tzname)
return '(%s)::date' % field_name
def datetime_cast_time_sql(self, field_name, tzname):
field_name = self._convert_field_to_tz(field_name, tzname)
return '(%s)::time' % field_name
def datetime_extract_sql(self, lookup_type, field_name, tzname):
field_name = self._convert_field_to_tz(field_name, tzname)
return self.date_extract_sql(lookup_type, field_name)
def datetime_trunc_sql(self, lookup_type, field_name, tzname):
field_name = self._convert_field_to_tz(field_name, tzname)
# https://www.postgresql.org/docs/current/functions-datetime.html#FUNCTIONS-DATETIME-TRUNC
return "DATE_TRUNC('%s', %s)" % (lookup_type, field_name)
def time_trunc_sql(self, lookup_type, field_name):
return "DATE_TRUNC('%s', %s)::time" % (lookup_type, field_name)
def json_cast_text_sql(self, field_name):
return '(%s)::text' % field_name
def deferrable_sql(self):
return " DEFERRABLE INITIALLY DEFERRED"
def fetch_returned_insert_rows(self, cursor):
"""
Given a cursor object that has just performed an INSERT...RETURNING
statement into a table, return the tuple of returned data.
"""
return cursor.fetchall()
def lookup_cast(self, lookup_type, internal_type=None):
lookup = '%s'
# Cast text lookups to text to allow things like filter(x__contains=4)
if lookup_type in ('iexact', 'contains', 'icontains', 'startswith',
'istartswith', 'endswith', 'iendswith', 'regex', 'iregex'):
if internal_type in ('IPAddressField', 'GenericIPAddressField'):
lookup = "HOST(%s)"
elif internal_type in ('CICharField', 'CIEmailField', 'CITextField'):
lookup = '%s::citext'
else:
lookup = "%s::text"
# Use UPPER(x) for case-insensitive lookups; it's faster.
if lookup_type in ('iexact', 'icontains', 'istartswith', 'iendswith'):
lookup = 'UPPER(%s)' % lookup
return lookup
def no_limit_value(self):
return None
def prepare_sql_script(self, sql):
return [sql]
def quote_name(self, name):
if name.startswith('"') and name.endswith('"'):
return name # Quoting once is enough.
return '"%s"' % name
def set_time_zone_sql(self):
return "SET TIME ZONE %s"
def sql_flush(self, style, tables, *, reset_sequences=False, allow_cascade=False):
if not tables:
return []
# Perform a single SQL 'TRUNCATE x, y, z...;' statement. It allows us
# to truncate tables referenced by a foreign key in any other table.
sql_parts = [
style.SQL_KEYWORD('TRUNCATE'),
', '.join(style.SQL_FIELD(self.quote_name(table)) for table in tables),
]
if reset_sequences:
sql_parts.append(style.SQL_KEYWORD('RESTART IDENTITY'))
if allow_cascade:
sql_parts.append(style.SQL_KEYWORD('CASCADE'))
return ['%s;' % ' '.join(sql_parts)]
def sequence_reset_by_name_sql(self, style, sequences):
# 'ALTER SEQUENCE sequence_name RESTART WITH 1;'... style SQL statements
# to reset sequence indices
sql = []
for sequence_info in sequences:
table_name = sequence_info['table']
# 'id' will be the case if it's an m2m using an autogenerated
# intermediate table (see BaseDatabaseIntrospection.sequence_list).
column_name = sequence_info['column'] or 'id'
sql.append("%s setval(pg_get_serial_sequence('%s','%s'), 1, false);" % (
style.SQL_KEYWORD('SELECT'),
style.SQL_TABLE(self.quote_name(table_name)),
style.SQL_FIELD(column_name),
))
return sql
def tablespace_sql(self, tablespace, inline=False):
if inline:
return "USING INDEX TABLESPACE %s" % self.quote_name(tablespace)
else:
return "TABLESPACE %s" % self.quote_name(tablespace)
def sequence_reset_sql(self, style, model_list):
from django.db import models
output = []
qn = self.quote_name
for model in model_list:
# Use `coalesce` to set the sequence for each model to the max pk value if there are records,
# or 1 if there are none. Set the `is_called` property (the third argument to `setval`) to true
# if there are records (as the max pk value is already in use), otherwise set it to false.
# Use pg_get_serial_sequence to get the underlying sequence name from the table name
# and column name (available since PostgreSQL 8)
for f in model._meta.local_fields:
if isinstance(f, models.AutoField):
output.append(
"%s setval(pg_get_serial_sequence('%s','%s'), "
"coalesce(max(%s), 1), max(%s) %s null) %s %s;" % (
style.SQL_KEYWORD('SELECT'),
style.SQL_TABLE(qn(model._meta.db_table)),
style.SQL_FIELD(f.column),
style.SQL_FIELD(qn(f.column)),
style.SQL_FIELD(qn(f.column)),
style.SQL_KEYWORD('IS NOT'),
style.SQL_KEYWORD('FROM'),
style.SQL_TABLE(qn(model._meta.db_table)),
)
)
break # Only one AutoField is allowed per model, so don't bother continuing.
for f in model._meta.many_to_many:
if not f.remote_field.through:
output.append(
"%s setval(pg_get_serial_sequence('%s','%s'), "
"coalesce(max(%s), 1), max(%s) %s null) %s %s;" % (
style.SQL_KEYWORD('SELECT'),
style.SQL_TABLE(qn(f.m2m_db_table())),
style.SQL_FIELD('id'),
style.SQL_FIELD(qn('id')),
style.SQL_FIELD(qn('id')),
style.SQL_KEYWORD('IS NOT'),
style.SQL_KEYWORD('FROM'),
style.SQL_TABLE(qn(f.m2m_db_table()))
)
)
return output
def prep_for_iexact_query(self, x):
return x
def max_name_length(self):
"""
Return the maximum length of an identifier.
The maximum length of an identifier is 63 by default, but can be
changed by recompiling PostgreSQL after editing the NAMEDATALEN
macro in src/include/pg_config_manual.h.
This implementation returns 63, but can be overridden by a custom
database backend that inherits most of its behavior from this one.
"""
return 63
def distinct_sql(self, fields, params):
if fields:
params = [param for param_list in params for param in param_list]
return (['DISTINCT ON (%s)' % ', '.join(fields)], params)
else:
return ['DISTINCT'], []
def last_executed_query(self, cursor, sql, params):
# https://www.psycopg.org/docs/cursor.html#cursor.query
# The query attribute is a Psycopg extension to the DB API 2.0.
if cursor.query is not None:
return cursor.query.decode()
return None
def return_insert_columns(self, fields):
if not fields:
return '', ()
columns = [
'%s.%s' % (
self.quote_name(field.model._meta.db_table),
self.quote_name(field.column),
) for field in fields
]
return 'RETURNING %s' % ', '.join(columns), ()
def bulk_insert_sql(self, fields, placeholder_rows):
placeholder_rows_sql = (", ".join(row) for row in placeholder_rows)
values_sql = ", ".join("(%s)" % sql for sql in placeholder_rows_sql)
return "VALUES " + values_sql
def adapt_datefield_value(self, value):
return value
def adapt_datetimefield_value(self, value):
return value
def adapt_timefield_value(self, value):
return value
def adapt_ipaddressfield_value(self, value):
if value:
return Inet(value)
return None
def subtract_temporals(self, internal_type, lhs, rhs):
if internal_type == 'DateField':
lhs_sql, lhs_params = lhs
rhs_sql, rhs_params = rhs
params = (*lhs_params, *rhs_params)
return "(interval '1 day' * (%s - %s))" % (lhs_sql, rhs_sql), params
return super().subtract_temporals(internal_type, lhs, rhs)
def explain_query_prefix(self, format=None, **options):
prefix = super().explain_query_prefix(format)
extra = {}
if format:
extra['FORMAT'] = format
if options:
extra.update({
name.upper(): 'true' if value else 'false'
for name, value in options.items()
})
if extra:
prefix += ' (%s)' % ', '.join('%s %s' % i for i in extra.items())
return prefix
def ignore_conflicts_suffix_sql(self, ignore_conflicts=None):
return 'ON CONFLICT DO NOTHING' if ignore_conflicts else super().ignore_conflicts_suffix_sql(ignore_conflicts)
|
1f087384a7cda45955f1c1cd7b5ed2143655a59b86568949bd18fca37be8ab28 | import os
import signal
import subprocess
from django.db.backends.base.client import BaseDatabaseClient
class DatabaseClient(BaseDatabaseClient):
executable_name = 'psql'
@classmethod
def runshell_db(cls, conn_params, parameters):
args = [cls.executable_name]
host = conn_params.get('host', '')
port = conn_params.get('port', '')
dbname = conn_params.get('database', '')
user = conn_params.get('user', '')
passwd = conn_params.get('password', '')
sslmode = conn_params.get('sslmode', '')
sslrootcert = conn_params.get('sslrootcert', '')
sslcert = conn_params.get('sslcert', '')
sslkey = conn_params.get('sslkey', '')
if user:
args += ['-U', user]
if host:
args += ['-h', host]
if port:
args += ['-p', str(port)]
args += [dbname]
args.extend(parameters)
sigint_handler = signal.getsignal(signal.SIGINT)
subprocess_env = os.environ.copy()
if passwd:
subprocess_env['PGPASSWORD'] = str(passwd)
if sslmode:
subprocess_env['PGSSLMODE'] = str(sslmode)
if sslrootcert:
subprocess_env['PGSSLROOTCERT'] = str(sslrootcert)
if sslcert:
subprocess_env['PGSSLCERT'] = str(sslcert)
if sslkey:
subprocess_env['PGSSLKEY'] = str(sslkey)
try:
# Allow SIGINT to pass to psql to abort queries.
signal.signal(signal.SIGINT, signal.SIG_IGN)
subprocess.run(args, check=True, env=subprocess_env)
finally:
# Restore the original SIGINT handler.
signal.signal(signal.SIGINT, sigint_handler)
def runshell(self, parameters):
self.runshell_db(self.connection.get_connection_params(), parameters)
|
62dcd3a8a075e34eb16612643dde1ab8a4684e9c7263be19bc3221c15198196f | import sys
from psycopg2 import errorcodes
from django.db.backends.base.creation import BaseDatabaseCreation
from django.db.backends.utils import strip_quotes
class DatabaseCreation(BaseDatabaseCreation):
def _quote_name(self, name):
return self.connection.ops.quote_name(name)
def _get_database_create_suffix(self, encoding=None, template=None):
suffix = ""
if encoding:
suffix += " ENCODING '{}'".format(encoding)
if template:
suffix += " TEMPLATE {}".format(self._quote_name(template))
return suffix and "WITH" + suffix
def sql_table_creation_suffix(self):
test_settings = self.connection.settings_dict['TEST']
assert test_settings['COLLATION'] is None, (
"PostgreSQL does not support collation setting at database creation time."
)
return self._get_database_create_suffix(
encoding=test_settings['CHARSET'],
template=test_settings.get('TEMPLATE'),
)
def _database_exists(self, cursor, database_name):
cursor.execute('SELECT 1 FROM pg_catalog.pg_database WHERE datname = %s', [strip_quotes(database_name)])
return cursor.fetchone() is not None
def _execute_create_test_db(self, cursor, parameters, keepdb=False):
try:
if keepdb and self._database_exists(cursor, parameters['dbname']):
# If the database should be kept and it already exists, don't
# try to create a new one.
return
super()._execute_create_test_db(cursor, parameters, keepdb)
except Exception as e:
if getattr(e.__cause__, 'pgcode', '') != errorcodes.DUPLICATE_DATABASE:
# All errors except "database already exists" cancel tests.
self.log('Got an error creating the test database: %s' % e)
sys.exit(2)
elif not keepdb:
# If the database should be kept, ignore "database already
# exists".
raise
def _clone_test_db(self, suffix, verbosity, keepdb=False):
# CREATE DATABASE ... WITH TEMPLATE ... requires closing connections
# to the template database.
self.connection.close()
source_database_name = self.connection.settings_dict['NAME']
target_database_name = self.get_test_db_clone_settings(suffix)['NAME']
test_db_params = {
'dbname': self._quote_name(target_database_name),
'suffix': self._get_database_create_suffix(template=source_database_name),
}
with self._nodb_cursor() as cursor:
try:
self._execute_create_test_db(cursor, test_db_params, keepdb)
except Exception:
try:
if verbosity >= 1:
self.log('Destroying old test database for alias %s...' % (
self._get_database_display_str(verbosity, target_database_name),
))
cursor.execute('DROP DATABASE %(dbname)s' % test_db_params)
self._execute_create_test_db(cursor, test_db_params, keepdb)
except Exception as e:
self.log('Got an error cloning the test database: %s' % e)
sys.exit(2)
|
457c981084ba01e048195a9cf500a5f37d3b26ae4861d31315a7ba80a8e42306 | import operator
from django.db import transaction
from django.db.backends.base.features import BaseDatabaseFeatures
from django.db.utils import OperationalError
from django.utils.functional import cached_property
from .base import Database
class DatabaseFeatures(BaseDatabaseFeatures):
# SQLite can read from a cursor since SQLite 3.6.5, subject to the caveat
# that statements within a connection aren't isolated from each other. See
# https://sqlite.org/isolation.html.
can_use_chunked_reads = True
test_db_allows_multiple_connections = False
supports_unspecified_pk = True
supports_timezones = False
max_query_params = 999
supports_mixed_date_datetime_comparisons = False
can_introspect_autofield = True
can_introspect_decimal_field = False
can_introspect_duration_field = False
can_introspect_positive_integer_field = True
can_introspect_small_integer_field = True
introspected_big_auto_field_type = 'AutoField'
introspected_small_auto_field_type = 'AutoField'
supports_transactions = True
atomic_transactions = False
can_rollback_ddl = True
supports_atomic_references_rename = Database.sqlite_version_info >= (3, 26, 0)
can_create_inline_fk = False
supports_paramstyle_pyformat = False
can_clone_databases = True
supports_temporal_subtraction = True
ignores_table_name_case = True
supports_cast_with_precision = False
time_cast_precision = 3
can_release_savepoints = True
# Is "ALTER TABLE ... RENAME COLUMN" supported?
can_alter_table_rename_column = Database.sqlite_version_info >= (3, 25, 0)
supports_parentheses_in_compound = False
# Deferred constraint checks can be emulated on SQLite < 3.20 but not in a
# reasonably performant way.
supports_pragma_foreign_key_check = Database.sqlite_version_info >= (3, 20, 0)
can_defer_constraint_checks = supports_pragma_foreign_key_check
supports_functions_in_partial_indexes = Database.sqlite_version_info >= (3, 15, 0)
supports_over_clause = Database.sqlite_version_info >= (3, 25, 0)
supports_frame_range_fixed_distance = Database.sqlite_version_info >= (3, 28, 0)
supports_aggregate_filter_clause = Database.sqlite_version_info >= (3, 30, 1)
supports_order_by_nulls_modifier = Database.sqlite_version_info >= (3, 30, 0)
order_by_nulls_first = True
@cached_property
def supports_json_field(self):
try:
with self.connection.cursor() as cursor, transaction.atomic():
cursor.execute('SELECT JSON(\'{"a": "b"}\')')
except OperationalError:
return False
return True
can_introspect_json_field = property(operator.attrgetter('supports_json_field'))
|
892da0c46406051fd2214b1b6993f0fa4c7c349141182ba9db0356eb5dc9d7e0 | import re
from collections import namedtuple
import sqlparse
from django.db.backends.base.introspection import (
BaseDatabaseIntrospection, FieldInfo as BaseFieldInfo, TableInfo,
)
from django.db.models import Index
from django.utils.regex_helper import _lazy_re_compile
FieldInfo = namedtuple('FieldInfo', BaseFieldInfo._fields + ('pk', 'has_json_constraint'))
field_size_re = _lazy_re_compile(r'^\s*(?:var)?char\s*\(\s*(\d+)\s*\)\s*$')
def get_field_size(name):
""" Extract the size number from a "varchar(11)" type name """
m = field_size_re.search(name)
return int(m.group(1)) if m else None
# This light wrapper "fakes" a dictionary interface, because some SQLite data
# types include variables in them -- e.g. "varchar(30)" -- and can't be matched
# as a simple dictionary lookup.
class FlexibleFieldLookupDict:
# Maps SQL types to Django Field types. Some of the SQL types have multiple
# entries here because SQLite allows for anything and doesn't normalize the
# field type; it uses whatever was given.
base_data_types_reverse = {
'bool': 'BooleanField',
'boolean': 'BooleanField',
'smallint': 'SmallIntegerField',
'smallint unsigned': 'PositiveSmallIntegerField',
'smallinteger': 'SmallIntegerField',
'int': 'IntegerField',
'integer': 'IntegerField',
'bigint': 'BigIntegerField',
'integer unsigned': 'PositiveIntegerField',
'bigint unsigned': 'PositiveBigIntegerField',
'decimal': 'DecimalField',
'real': 'FloatField',
'text': 'TextField',
'char': 'CharField',
'varchar': 'CharField',
'blob': 'BinaryField',
'date': 'DateField',
'datetime': 'DateTimeField',
'time': 'TimeField',
}
def __getitem__(self, key):
key = key.lower().split('(', 1)[0].strip()
return self.base_data_types_reverse[key]
class DatabaseIntrospection(BaseDatabaseIntrospection):
data_types_reverse = FlexibleFieldLookupDict()
def get_field_type(self, data_type, description):
field_type = super().get_field_type(data_type, description)
if description.pk and field_type in {'BigIntegerField', 'IntegerField', 'SmallIntegerField'}:
# No support for BigAutoField or SmallAutoField as SQLite treats
# all integer primary keys as signed 64-bit integers.
return 'AutoField'
if description.has_json_constraint:
return 'JSONField'
return field_type
def get_table_list(self, cursor):
"""Return a list of table and view names in the current database."""
# Skip the sqlite_sequence system table used for autoincrement key
# generation.
cursor.execute("""
SELECT name, type FROM sqlite_master
WHERE type in ('table', 'view') AND NOT name='sqlite_sequence'
ORDER BY name""")
return [TableInfo(row[0], row[1][0]) for row in cursor.fetchall()]
def get_table_description(self, cursor, table_name):
"""
Return a description of the table with the DB-API cursor.description
interface.
"""
cursor.execute('PRAGMA table_info(%s)' % self.connection.ops.quote_name(table_name))
table_info = cursor.fetchall()
json_columns = set()
if self.connection.features.can_introspect_json_field:
for line in table_info:
column = line[1]
json_constraint_sql = '%%json_valid("%s")%%' % column
has_json_constraint = cursor.execute("""
SELECT sql
FROM sqlite_master
WHERE
type = 'table' AND
name = %s AND
sql LIKE %s
""", [table_name, json_constraint_sql]).fetchone()
if has_json_constraint:
json_columns.add(column)
return [
FieldInfo(
name, data_type, None, get_field_size(data_type), None, None,
not notnull, default, pk == 1, name in json_columns
)
for cid, name, data_type, notnull, default, pk in table_info
]
def get_sequences(self, cursor, table_name, table_fields=()):
pk_col = self.get_primary_key_column(cursor, table_name)
return [{'table': table_name, 'column': pk_col}]
def get_relations(self, cursor, table_name):
"""
Return a dictionary of {field_name: (field_name_other_table, other_table)}
representing all relationships to the given table.
"""
# Dictionary of relations to return
relations = {}
# Schema for this table
cursor.execute(
"SELECT sql, type FROM sqlite_master "
"WHERE tbl_name = %s AND type IN ('table', 'view')",
[table_name]
)
create_sql, table_type = cursor.fetchone()
if table_type == 'view':
# It might be a view, then no results will be returned
return relations
results = create_sql[create_sql.index('(') + 1:create_sql.rindex(')')]
# Walk through and look for references to other tables. SQLite doesn't
# really have enforced references, but since it echoes out the SQL used
# to create the table we can look for REFERENCES statements used there.
for field_desc in results.split(','):
field_desc = field_desc.strip()
if field_desc.startswith("UNIQUE"):
continue
m = re.search(r'references (\S*) ?\(["|]?(.*)["|]?\)', field_desc, re.I)
if not m:
continue
table, column = [s.strip('"') for s in m.groups()]
if field_desc.startswith("FOREIGN KEY"):
# Find name of the target FK field
m = re.match(r'FOREIGN KEY\s*\(([^\)]*)\).*', field_desc, re.I)
field_name = m.groups()[0].strip('"')
else:
field_name = field_desc.split()[0].strip('"')
cursor.execute("SELECT sql FROM sqlite_master WHERE tbl_name = %s", [table])
result = cursor.fetchall()[0]
other_table_results = result[0].strip()
li, ri = other_table_results.index('('), other_table_results.rindex(')')
other_table_results = other_table_results[li + 1:ri]
for other_desc in other_table_results.split(','):
other_desc = other_desc.strip()
if other_desc.startswith('UNIQUE'):
continue
other_name = other_desc.split(' ', 1)[0].strip('"')
if other_name == column:
relations[field_name] = (other_name, table)
break
return relations
def get_key_columns(self, cursor, table_name):
"""
Return a list of (column_name, referenced_table_name, referenced_column_name)
for all key columns in given table.
"""
key_columns = []
# Schema for this table
cursor.execute("SELECT sql FROM sqlite_master WHERE tbl_name = %s AND type = %s", [table_name, "table"])
results = cursor.fetchone()[0].strip()
results = results[results.index('(') + 1:results.rindex(')')]
# Walk through and look for references to other tables. SQLite doesn't
# really have enforced references, but since it echoes out the SQL used
# to create the table we can look for REFERENCES statements used there.
for field_index, field_desc in enumerate(results.split(',')):
field_desc = field_desc.strip()
if field_desc.startswith("UNIQUE"):
continue
m = re.search(r'"(.*)".*references (.*) \(["|](.*)["|]\)', field_desc, re.I)
if not m:
continue
# This will append (column_name, referenced_table_name, referenced_column_name) to key_columns
key_columns.append(tuple(s.strip('"') for s in m.groups()))
return key_columns
def get_primary_key_column(self, cursor, table_name):
"""Return the column name of the primary key for the given table."""
# Don't use PRAGMA because that causes issues with some transactions
cursor.execute(
"SELECT sql, type FROM sqlite_master "
"WHERE tbl_name = %s AND type IN ('table', 'view')",
[table_name]
)
row = cursor.fetchone()
if row is None:
raise ValueError("Table %s does not exist" % table_name)
create_sql, table_type = row
if table_type == 'view':
# Views don't have a primary key.
return None
fields_sql = create_sql[create_sql.index('(') + 1:create_sql.rindex(')')]
for field_desc in fields_sql.split(','):
field_desc = field_desc.strip()
m = re.match(r'(?:(?:["`\[])(.*)(?:["`\]])|(\w+)).*PRIMARY KEY.*', field_desc)
if m:
return m.group(1) if m.group(1) else m.group(2)
return None
def _get_foreign_key_constraints(self, cursor, table_name):
constraints = {}
cursor.execute('PRAGMA foreign_key_list(%s)' % self.connection.ops.quote_name(table_name))
for row in cursor.fetchall():
# Remaining on_update/on_delete/match values are of no interest.
id_, _, table, from_, to = row[:5]
constraints['fk_%d' % id_] = {
'columns': [from_],
'primary_key': False,
'unique': False,
'foreign_key': (table, to),
'check': False,
'index': False,
}
return constraints
def _parse_column_or_constraint_definition(self, tokens, columns):
token = None
is_constraint_definition = None
field_name = None
constraint_name = None
unique = False
unique_columns = []
check = False
check_columns = []
braces_deep = 0
for token in tokens:
if token.match(sqlparse.tokens.Punctuation, '('):
braces_deep += 1
elif token.match(sqlparse.tokens.Punctuation, ')'):
braces_deep -= 1
if braces_deep < 0:
# End of columns and constraints for table definition.
break
elif braces_deep == 0 and token.match(sqlparse.tokens.Punctuation, ','):
# End of current column or constraint definition.
break
# Detect column or constraint definition by first token.
if is_constraint_definition is None:
is_constraint_definition = token.match(sqlparse.tokens.Keyword, 'CONSTRAINT')
if is_constraint_definition:
continue
if is_constraint_definition:
# Detect constraint name by second token.
if constraint_name is None:
if token.ttype in (sqlparse.tokens.Name, sqlparse.tokens.Keyword):
constraint_name = token.value
elif token.ttype == sqlparse.tokens.Literal.String.Symbol:
constraint_name = token.value[1:-1]
# Start constraint columns parsing after UNIQUE keyword.
if token.match(sqlparse.tokens.Keyword, 'UNIQUE'):
unique = True
unique_braces_deep = braces_deep
elif unique:
if unique_braces_deep == braces_deep:
if unique_columns:
# Stop constraint parsing.
unique = False
continue
if token.ttype in (sqlparse.tokens.Name, sqlparse.tokens.Keyword):
unique_columns.append(token.value)
elif token.ttype == sqlparse.tokens.Literal.String.Symbol:
unique_columns.append(token.value[1:-1])
else:
# Detect field name by first token.
if field_name is None:
if token.ttype in (sqlparse.tokens.Name, sqlparse.tokens.Keyword):
field_name = token.value
elif token.ttype == sqlparse.tokens.Literal.String.Symbol:
field_name = token.value[1:-1]
if token.match(sqlparse.tokens.Keyword, 'UNIQUE'):
unique_columns = [field_name]
# Start constraint columns parsing after CHECK keyword.
if token.match(sqlparse.tokens.Keyword, 'CHECK'):
check = True
check_braces_deep = braces_deep
elif check:
if check_braces_deep == braces_deep:
if check_columns:
# Stop constraint parsing.
check = False
continue
if token.ttype in (sqlparse.tokens.Name, sqlparse.tokens.Keyword):
if token.value in columns:
check_columns.append(token.value)
elif token.ttype == sqlparse.tokens.Literal.String.Symbol:
if token.value[1:-1] in columns:
check_columns.append(token.value[1:-1])
unique_constraint = {
'unique': True,
'columns': unique_columns,
'primary_key': False,
'foreign_key': None,
'check': False,
'index': False,
} if unique_columns else None
check_constraint = {
'check': True,
'columns': check_columns,
'primary_key': False,
'unique': False,
'foreign_key': None,
'index': False,
} if check_columns else None
return constraint_name, unique_constraint, check_constraint, token
def _parse_table_constraints(self, sql, columns):
# Check constraint parsing is based of SQLite syntax diagram.
# https://www.sqlite.org/syntaxdiagrams.html#table-constraint
statement = sqlparse.parse(sql)[0]
constraints = {}
unnamed_constrains_index = 0
tokens = (token for token in statement.flatten() if not token.is_whitespace)
# Go to columns and constraint definition
for token in tokens:
if token.match(sqlparse.tokens.Punctuation, '('):
break
# Parse columns and constraint definition
while True:
constraint_name, unique, check, end_token = self._parse_column_or_constraint_definition(tokens, columns)
if unique:
if constraint_name:
constraints[constraint_name] = unique
else:
unnamed_constrains_index += 1
constraints['__unnamed_constraint_%s__' % unnamed_constrains_index] = unique
if check:
if constraint_name:
constraints[constraint_name] = check
else:
unnamed_constrains_index += 1
constraints['__unnamed_constraint_%s__' % unnamed_constrains_index] = check
if end_token.match(sqlparse.tokens.Punctuation, ')'):
break
return constraints
def get_constraints(self, cursor, table_name):
"""
Retrieve any constraints or keys (unique, pk, fk, check, index) across
one or more columns.
"""
constraints = {}
# Find inline check constraints.
try:
table_schema = cursor.execute(
"SELECT sql FROM sqlite_master WHERE type='table' and name=%s" % (
self.connection.ops.quote_name(table_name),
)
).fetchone()[0]
except TypeError:
# table_name is a view.
pass
else:
columns = {info.name for info in self.get_table_description(cursor, table_name)}
constraints.update(self._parse_table_constraints(table_schema, columns))
# Get the index info
cursor.execute("PRAGMA index_list(%s)" % self.connection.ops.quote_name(table_name))
for row in cursor.fetchall():
# SQLite 3.8.9+ has 5 columns, however older versions only give 3
# columns. Discard last 2 columns if there.
number, index, unique = row[:3]
cursor.execute(
"SELECT sql FROM sqlite_master "
"WHERE type='index' AND name=%s" % self.connection.ops.quote_name(index)
)
# There's at most one row.
sql, = cursor.fetchone() or (None,)
# Inline constraints are already detected in
# _parse_table_constraints(). The reasons to avoid fetching inline
# constraints from `PRAGMA index_list` are:
# - Inline constraints can have a different name and information
# than what `PRAGMA index_list` gives.
# - Not all inline constraints may appear in `PRAGMA index_list`.
if not sql:
# An inline constraint
continue
# Get the index info for that index
cursor.execute('PRAGMA index_info(%s)' % self.connection.ops.quote_name(index))
for index_rank, column_rank, column in cursor.fetchall():
if index not in constraints:
constraints[index] = {
"columns": [],
"primary_key": False,
"unique": bool(unique),
"foreign_key": None,
"check": False,
"index": True,
}
constraints[index]['columns'].append(column)
# Add type and column orders for indexes
if constraints[index]['index'] and not constraints[index]['unique']:
# SQLite doesn't support any index type other than b-tree
constraints[index]['type'] = Index.suffix
order_info = sql.split('(')[-1].split(')')[0].split(',')
orders = ['DESC' if info.endswith('DESC') else 'ASC' for info in order_info]
constraints[index]['orders'] = orders
# Get the PK
pk_column = self.get_primary_key_column(cursor, table_name)
if pk_column:
# SQLite doesn't actually give a name to the PK constraint,
# so we invent one. This is fine, as the SQLite backend never
# deletes PK constraints by name, as you can't delete constraints
# in SQLite; we remake the table with a new PK instead.
constraints["__primary__"] = {
"columns": [pk_column],
"primary_key": True,
"unique": False, # It's not actually a unique constraint.
"foreign_key": None,
"check": False,
"index": False,
}
constraints.update(self._get_foreign_key_constraints(cursor, table_name))
return constraints
|
bb6be84c619bd443bdd82e8cda80ea0e8b3c7cb5d1d244a94b5609bca6ad7859 | """
SQLite backend for the sqlite3 module in the standard library.
"""
import datetime
import decimal
import functools
import hashlib
import json
import math
import operator
import re
import statistics
import warnings
from itertools import chain
from sqlite3 import dbapi2 as Database
import pytz
from django.core.exceptions import ImproperlyConfigured
from django.db import IntegrityError
from django.db.backends import utils as backend_utils
from django.db.backends.base.base import BaseDatabaseWrapper
from django.utils import timezone
from django.utils.asyncio import async_unsafe
from django.utils.dateparse import parse_datetime, parse_time
from django.utils.duration import duration_microseconds
from django.utils.regex_helper import _lazy_re_compile
from django.utils.version import PY38
from .client import DatabaseClient # isort:skip
from .creation import DatabaseCreation # isort:skip
from .features import DatabaseFeatures # isort:skip
from .introspection import DatabaseIntrospection # isort:skip
from .operations import DatabaseOperations # isort:skip
from .schema import DatabaseSchemaEditor # isort:skip
def decoder(conv_func):
"""
Convert bytestrings from Python's sqlite3 interface to a regular string.
"""
return lambda s: conv_func(s.decode())
def none_guard(func):
"""
Decorator that returns None if any of the arguments to the decorated
function are None. Many SQL functions return NULL if any of their arguments
are NULL. This decorator simplifies the implementation of this for the
custom functions registered below.
"""
@functools.wraps(func)
def wrapper(*args, **kwargs):
return None if None in args else func(*args, **kwargs)
return wrapper
def list_aggregate(function):
"""
Return an aggregate class that accumulates values in a list and applies
the provided function to the data.
"""
return type('ListAggregate', (list,), {'finalize': function, 'step': list.append})
def check_sqlite_version():
if Database.sqlite_version_info < (3, 8, 3):
raise ImproperlyConfigured('SQLite 3.8.3 or later is required (found %s).' % Database.sqlite_version)
check_sqlite_version()
Database.register_converter("bool", b'1'.__eq__)
Database.register_converter("time", decoder(parse_time))
Database.register_converter("datetime", decoder(parse_datetime))
Database.register_converter("timestamp", decoder(parse_datetime))
Database.register_converter("TIMESTAMP", decoder(parse_datetime))
Database.register_adapter(decimal.Decimal, str)
class DatabaseWrapper(BaseDatabaseWrapper):
vendor = 'sqlite'
display_name = 'SQLite'
# SQLite doesn't actually support most of these types, but it "does the right
# thing" given more verbose field definitions, so leave them as is so that
# schema inspection is more useful.
data_types = {
'AutoField': 'integer',
'BigAutoField': 'integer',
'BinaryField': 'BLOB',
'BooleanField': 'bool',
'CharField': 'varchar(%(max_length)s)',
'DateField': 'date',
'DateTimeField': 'datetime',
'DecimalField': 'decimal',
'DurationField': 'bigint',
'FileField': 'varchar(%(max_length)s)',
'FilePathField': 'varchar(%(max_length)s)',
'FloatField': 'real',
'IntegerField': 'integer',
'BigIntegerField': 'bigint',
'IPAddressField': 'char(15)',
'GenericIPAddressField': 'char(39)',
'JSONField': 'text',
'NullBooleanField': 'bool',
'OneToOneField': 'integer',
'PositiveBigIntegerField': 'bigint unsigned',
'PositiveIntegerField': 'integer unsigned',
'PositiveSmallIntegerField': 'smallint unsigned',
'SlugField': 'varchar(%(max_length)s)',
'SmallAutoField': 'integer',
'SmallIntegerField': 'smallint',
'TextField': 'text',
'TimeField': 'time',
'UUIDField': 'char(32)',
}
data_type_check_constraints = {
'PositiveBigIntegerField': '"%(column)s" >= 0',
'JSONField': '(JSON_VALID("%(column)s") OR "%(column)s" IS NULL)',
'PositiveIntegerField': '"%(column)s" >= 0',
'PositiveSmallIntegerField': '"%(column)s" >= 0',
}
data_types_suffix = {
'AutoField': 'AUTOINCREMENT',
'BigAutoField': 'AUTOINCREMENT',
'SmallAutoField': 'AUTOINCREMENT',
}
# SQLite requires LIKE statements to include an ESCAPE clause if the value
# being escaped has a percent or underscore in it.
# See https://www.sqlite.org/lang_expr.html for an explanation.
operators = {
'exact': '= %s',
'iexact': "LIKE %s ESCAPE '\\'",
'contains': "LIKE %s ESCAPE '\\'",
'icontains': "LIKE %s ESCAPE '\\'",
'regex': 'REGEXP %s',
'iregex': "REGEXP '(?i)' || %s",
'gt': '> %s',
'gte': '>= %s',
'lt': '< %s',
'lte': '<= %s',
'startswith': "LIKE %s ESCAPE '\\'",
'endswith': "LIKE %s ESCAPE '\\'",
'istartswith': "LIKE %s ESCAPE '\\'",
'iendswith': "LIKE %s ESCAPE '\\'",
}
# The patterns below are used to generate SQL pattern lookup clauses when
# the right-hand side of the lookup isn't a raw string (it might be an expression
# or the result of a bilateral transformation).
# In those cases, special characters for LIKE operators (e.g. \, *, _) should be
# escaped on database side.
#
# Note: we use str.format() here for readability as '%' is used as a wildcard for
# the LIKE operator.
pattern_esc = r"REPLACE(REPLACE(REPLACE({}, '\', '\\'), '%%', '\%%'), '_', '\_')"
pattern_ops = {
'contains': r"LIKE '%%' || {} || '%%' ESCAPE '\'",
'icontains': r"LIKE '%%' || UPPER({}) || '%%' ESCAPE '\'",
'startswith': r"LIKE {} || '%%' ESCAPE '\'",
'istartswith': r"LIKE UPPER({}) || '%%' ESCAPE '\'",
'endswith': r"LIKE '%%' || {} ESCAPE '\'",
'iendswith': r"LIKE '%%' || UPPER({}) ESCAPE '\'",
}
Database = Database
SchemaEditorClass = DatabaseSchemaEditor
# Classes instantiated in __init__().
client_class = DatabaseClient
creation_class = DatabaseCreation
features_class = DatabaseFeatures
introspection_class = DatabaseIntrospection
ops_class = DatabaseOperations
def get_connection_params(self):
settings_dict = self.settings_dict
if not settings_dict['NAME']:
raise ImproperlyConfigured(
"settings.DATABASES is improperly configured. "
"Please supply the NAME value.")
kwargs = {
# TODO: Remove str() when dropping support for PY36.
# https://bugs.python.org/issue33496
'database': str(settings_dict['NAME']),
'detect_types': Database.PARSE_DECLTYPES | Database.PARSE_COLNAMES,
**settings_dict['OPTIONS'],
}
# Always allow the underlying SQLite connection to be shareable
# between multiple threads. The safe-guarding will be handled at a
# higher level by the `BaseDatabaseWrapper.allow_thread_sharing`
# property. This is necessary as the shareability is disabled by
# default in pysqlite and it cannot be changed once a connection is
# opened.
if 'check_same_thread' in kwargs and kwargs['check_same_thread']:
warnings.warn(
'The `check_same_thread` option was provided and set to '
'True. It will be overridden with False. Use the '
'`DatabaseWrapper.allow_thread_sharing` property instead '
'for controlling thread shareability.',
RuntimeWarning
)
kwargs.update({'check_same_thread': False, 'uri': True})
return kwargs
@async_unsafe
def get_new_connection(self, conn_params):
conn = Database.connect(**conn_params)
if PY38:
create_deterministic_function = functools.partial(
conn.create_function,
deterministic=True,
)
else:
create_deterministic_function = conn.create_function
create_deterministic_function('django_date_extract', 2, _sqlite_datetime_extract)
create_deterministic_function('django_date_trunc', 2, _sqlite_date_trunc)
create_deterministic_function('django_datetime_cast_date', 3, _sqlite_datetime_cast_date)
create_deterministic_function('django_datetime_cast_time', 3, _sqlite_datetime_cast_time)
create_deterministic_function('django_datetime_extract', 4, _sqlite_datetime_extract)
create_deterministic_function('django_datetime_trunc', 4, _sqlite_datetime_trunc)
create_deterministic_function('django_time_extract', 2, _sqlite_time_extract)
create_deterministic_function('django_time_trunc', 2, _sqlite_time_trunc)
create_deterministic_function('django_time_diff', 2, _sqlite_time_diff)
create_deterministic_function('django_timestamp_diff', 2, _sqlite_timestamp_diff)
create_deterministic_function('django_format_dtdelta', 3, _sqlite_format_dtdelta)
create_deterministic_function('regexp', 2, _sqlite_regexp)
create_deterministic_function('ACOS', 1, none_guard(math.acos))
create_deterministic_function('ASIN', 1, none_guard(math.asin))
create_deterministic_function('ATAN', 1, none_guard(math.atan))
create_deterministic_function('ATAN2', 2, none_guard(math.atan2))
create_deterministic_function('BITXOR', 2, none_guard(operator.xor))
create_deterministic_function('CEILING', 1, none_guard(math.ceil))
create_deterministic_function('COS', 1, none_guard(math.cos))
create_deterministic_function('COT', 1, none_guard(lambda x: 1 / math.tan(x)))
create_deterministic_function('DEGREES', 1, none_guard(math.degrees))
create_deterministic_function('EXP', 1, none_guard(math.exp))
create_deterministic_function('FLOOR', 1, none_guard(math.floor))
create_deterministic_function('JSON_CONTAINS', 2, _sqlite_json_contains)
create_deterministic_function('LN', 1, none_guard(math.log))
create_deterministic_function('LOG', 2, none_guard(lambda x, y: math.log(y, x)))
create_deterministic_function('LPAD', 3, _sqlite_lpad)
create_deterministic_function('MD5', 1, none_guard(lambda x: hashlib.md5(x.encode()).hexdigest()))
create_deterministic_function('MOD', 2, none_guard(math.fmod))
create_deterministic_function('PI', 0, lambda: math.pi)
create_deterministic_function('POWER', 2, none_guard(operator.pow))
create_deterministic_function('RADIANS', 1, none_guard(math.radians))
create_deterministic_function('REPEAT', 2, none_guard(operator.mul))
create_deterministic_function('REVERSE', 1, none_guard(lambda x: x[::-1]))
create_deterministic_function('RPAD', 3, _sqlite_rpad)
create_deterministic_function('SHA1', 1, none_guard(lambda x: hashlib.sha1(x.encode()).hexdigest()))
create_deterministic_function('SHA224', 1, none_guard(lambda x: hashlib.sha224(x.encode()).hexdigest()))
create_deterministic_function('SHA256', 1, none_guard(lambda x: hashlib.sha256(x.encode()).hexdigest()))
create_deterministic_function('SHA384', 1, none_guard(lambda x: hashlib.sha384(x.encode()).hexdigest()))
create_deterministic_function('SHA512', 1, none_guard(lambda x: hashlib.sha512(x.encode()).hexdigest()))
create_deterministic_function('SIGN', 1, none_guard(lambda x: (x > 0) - (x < 0)))
create_deterministic_function('SIN', 1, none_guard(math.sin))
create_deterministic_function('SQRT', 1, none_guard(math.sqrt))
create_deterministic_function('TAN', 1, none_guard(math.tan))
conn.create_aggregate('STDDEV_POP', 1, list_aggregate(statistics.pstdev))
conn.create_aggregate('STDDEV_SAMP', 1, list_aggregate(statistics.stdev))
conn.create_aggregate('VAR_POP', 1, list_aggregate(statistics.pvariance))
conn.create_aggregate('VAR_SAMP', 1, list_aggregate(statistics.variance))
conn.execute('PRAGMA foreign_keys = ON')
return conn
def init_connection_state(self):
pass
def create_cursor(self, name=None):
return self.connection.cursor(factory=SQLiteCursorWrapper)
@async_unsafe
def close(self):
self.validate_thread_sharing()
# If database is in memory, closing the connection destroys the
# database. To prevent accidental data loss, ignore close requests on
# an in-memory db.
if not self.is_in_memory_db():
BaseDatabaseWrapper.close(self)
def _savepoint_allowed(self):
# When 'isolation_level' is not None, sqlite3 commits before each
# savepoint; it's a bug. When it is None, savepoints don't make sense
# because autocommit is enabled. The only exception is inside 'atomic'
# blocks. To work around that bug, on SQLite, 'atomic' starts a
# transaction explicitly rather than simply disable autocommit.
return self.in_atomic_block
def _set_autocommit(self, autocommit):
if autocommit:
level = None
else:
# sqlite3's internal default is ''. It's different from None.
# See Modules/_sqlite/connection.c.
level = ''
# 'isolation_level' is a misleading API.
# SQLite always runs at the SERIALIZABLE isolation level.
with self.wrap_database_errors:
self.connection.isolation_level = level
def disable_constraint_checking(self):
with self.cursor() as cursor:
cursor.execute('PRAGMA foreign_keys = OFF')
# Foreign key constraints cannot be turned off while in a multi-
# statement transaction. Fetch the current state of the pragma
# to determine if constraints are effectively disabled.
enabled = cursor.execute('PRAGMA foreign_keys').fetchone()[0]
return not bool(enabled)
def enable_constraint_checking(self):
with self.cursor() as cursor:
cursor.execute('PRAGMA foreign_keys = ON')
def check_constraints(self, table_names=None):
"""
Check each table name in `table_names` for rows with invalid foreign
key references. This method is intended to be used in conjunction with
`disable_constraint_checking()` and `enable_constraint_checking()`, to
determine if rows with invalid references were entered while constraint
checks were off.
"""
if self.features.supports_pragma_foreign_key_check:
with self.cursor() as cursor:
if table_names is None:
violations = cursor.execute('PRAGMA foreign_key_check').fetchall()
else:
violations = chain.from_iterable(
cursor.execute('PRAGMA foreign_key_check(%s)' % table_name).fetchall()
for table_name in table_names
)
# See https://www.sqlite.org/pragma.html#pragma_foreign_key_check
for table_name, rowid, referenced_table_name, foreign_key_index in violations:
foreign_key = cursor.execute(
'PRAGMA foreign_key_list(%s)' % table_name
).fetchall()[foreign_key_index]
column_name, referenced_column_name = foreign_key[3:5]
primary_key_column_name = self.introspection.get_primary_key_column(cursor, table_name)
primary_key_value, bad_value = cursor.execute(
'SELECT %s, %s FROM %s WHERE rowid = %%s' % (
primary_key_column_name, column_name, table_name
),
(rowid,),
).fetchone()
raise IntegrityError(
"The row in table '%s' with primary key '%s' has an "
"invalid foreign key: %s.%s contains a value '%s' that "
"does not have a corresponding value in %s.%s." % (
table_name, primary_key_value, table_name, column_name,
bad_value, referenced_table_name, referenced_column_name
)
)
else:
with self.cursor() as cursor:
if table_names is None:
table_names = self.introspection.table_names(cursor)
for table_name in table_names:
primary_key_column_name = self.introspection.get_primary_key_column(cursor, table_name)
if not primary_key_column_name:
continue
key_columns = self.introspection.get_key_columns(cursor, table_name)
for column_name, referenced_table_name, referenced_column_name in key_columns:
cursor.execute(
"""
SELECT REFERRING.`%s`, REFERRING.`%s` FROM `%s` as REFERRING
LEFT JOIN `%s` as REFERRED
ON (REFERRING.`%s` = REFERRED.`%s`)
WHERE REFERRING.`%s` IS NOT NULL AND REFERRED.`%s` IS NULL
"""
% (
primary_key_column_name, column_name, table_name,
referenced_table_name, column_name, referenced_column_name,
column_name, referenced_column_name,
)
)
for bad_row in cursor.fetchall():
raise IntegrityError(
"The row in table '%s' with primary key '%s' has an "
"invalid foreign key: %s.%s contains a value '%s' that "
"does not have a corresponding value in %s.%s." % (
table_name, bad_row[0], table_name, column_name,
bad_row[1], referenced_table_name, referenced_column_name,
)
)
def is_usable(self):
return True
def _start_transaction_under_autocommit(self):
"""
Start a transaction explicitly in autocommit mode.
Staying in autocommit mode works around a bug of sqlite3 that breaks
savepoints when autocommit is disabled.
"""
self.cursor().execute("BEGIN")
def is_in_memory_db(self):
return self.creation.is_in_memory_db(self.settings_dict['NAME'])
FORMAT_QMARK_REGEX = _lazy_re_compile(r'(?<!%)%s')
class SQLiteCursorWrapper(Database.Cursor):
"""
Django uses "format" style placeholders, but pysqlite2 uses "qmark" style.
This fixes it -- but note that if you want to use a literal "%s" in a query,
you'll need to use "%%s".
"""
def execute(self, query, params=None):
if params is None:
return Database.Cursor.execute(self, query)
query = self.convert_query(query)
return Database.Cursor.execute(self, query, params)
def executemany(self, query, param_list):
query = self.convert_query(query)
return Database.Cursor.executemany(self, query, param_list)
def convert_query(self, query):
return FORMAT_QMARK_REGEX.sub('?', query).replace('%%', '%')
def _sqlite_datetime_parse(dt, tzname=None, conn_tzname=None):
if dt is None:
return None
try:
dt = backend_utils.typecast_timestamp(dt)
except (TypeError, ValueError):
return None
if conn_tzname:
dt = dt.replace(tzinfo=pytz.timezone(conn_tzname))
if tzname is not None and tzname != conn_tzname:
sign_index = tzname.find('+') + tzname.find('-') + 1
if sign_index > -1:
sign = tzname[sign_index]
tzname, offset = tzname.split(sign)
if offset:
hours, minutes = offset.split(':')
offset_delta = datetime.timedelta(hours=int(hours), minutes=int(minutes))
dt += offset_delta if sign == '+' else -offset_delta
dt = timezone.localtime(dt, pytz.timezone(tzname))
return dt
def _sqlite_date_trunc(lookup_type, dt):
dt = _sqlite_datetime_parse(dt)
if dt is None:
return None
if lookup_type == 'year':
return "%i-01-01" % dt.year
elif lookup_type == 'quarter':
month_in_quarter = dt.month - (dt.month - 1) % 3
return '%i-%02i-01' % (dt.year, month_in_quarter)
elif lookup_type == 'month':
return "%i-%02i-01" % (dt.year, dt.month)
elif lookup_type == 'week':
dt = dt - datetime.timedelta(days=dt.weekday())
return "%i-%02i-%02i" % (dt.year, dt.month, dt.day)
elif lookup_type == 'day':
return "%i-%02i-%02i" % (dt.year, dt.month, dt.day)
def _sqlite_time_trunc(lookup_type, dt):
if dt is None:
return None
try:
dt = backend_utils.typecast_time(dt)
except (ValueError, TypeError):
return None
if lookup_type == 'hour':
return "%02i:00:00" % dt.hour
elif lookup_type == 'minute':
return "%02i:%02i:00" % (dt.hour, dt.minute)
elif lookup_type == 'second':
return "%02i:%02i:%02i" % (dt.hour, dt.minute, dt.second)
def _sqlite_datetime_cast_date(dt, tzname, conn_tzname):
dt = _sqlite_datetime_parse(dt, tzname, conn_tzname)
if dt is None:
return None
return dt.date().isoformat()
def _sqlite_datetime_cast_time(dt, tzname, conn_tzname):
dt = _sqlite_datetime_parse(dt, tzname, conn_tzname)
if dt is None:
return None
return dt.time().isoformat()
def _sqlite_datetime_extract(lookup_type, dt, tzname=None, conn_tzname=None):
dt = _sqlite_datetime_parse(dt, tzname, conn_tzname)
if dt is None:
return None
if lookup_type == 'week_day':
return (dt.isoweekday() % 7) + 1
elif lookup_type == 'iso_week_day':
return dt.isoweekday()
elif lookup_type == 'week':
return dt.isocalendar()[1]
elif lookup_type == 'quarter':
return math.ceil(dt.month / 3)
elif lookup_type == 'iso_year':
return dt.isocalendar()[0]
else:
return getattr(dt, lookup_type)
def _sqlite_datetime_trunc(lookup_type, dt, tzname, conn_tzname):
dt = _sqlite_datetime_parse(dt, tzname, conn_tzname)
if dt is None:
return None
if lookup_type == 'year':
return "%i-01-01 00:00:00" % dt.year
elif lookup_type == 'quarter':
month_in_quarter = dt.month - (dt.month - 1) % 3
return '%i-%02i-01 00:00:00' % (dt.year, month_in_quarter)
elif lookup_type == 'month':
return "%i-%02i-01 00:00:00" % (dt.year, dt.month)
elif lookup_type == 'week':
dt = dt - datetime.timedelta(days=dt.weekday())
return "%i-%02i-%02i 00:00:00" % (dt.year, dt.month, dt.day)
elif lookup_type == 'day':
return "%i-%02i-%02i 00:00:00" % (dt.year, dt.month, dt.day)
elif lookup_type == 'hour':
return "%i-%02i-%02i %02i:00:00" % (dt.year, dt.month, dt.day, dt.hour)
elif lookup_type == 'minute':
return "%i-%02i-%02i %02i:%02i:00" % (dt.year, dt.month, dt.day, dt.hour, dt.minute)
elif lookup_type == 'second':
return "%i-%02i-%02i %02i:%02i:%02i" % (dt.year, dt.month, dt.day, dt.hour, dt.minute, dt.second)
def _sqlite_time_extract(lookup_type, dt):
if dt is None:
return None
try:
dt = backend_utils.typecast_time(dt)
except (ValueError, TypeError):
return None
return getattr(dt, lookup_type)
@none_guard
def _sqlite_format_dtdelta(conn, lhs, rhs):
"""
LHS and RHS can be either:
- An integer number of microseconds
- A string representing a datetime
"""
try:
real_lhs = datetime.timedelta(0, 0, lhs) if isinstance(lhs, int) else backend_utils.typecast_timestamp(lhs)
real_rhs = datetime.timedelta(0, 0, rhs) if isinstance(rhs, int) else backend_utils.typecast_timestamp(rhs)
if conn.strip() == '+':
out = real_lhs + real_rhs
else:
out = real_lhs - real_rhs
except (ValueError, TypeError):
return None
# typecast_timestamp returns a date or a datetime without timezone.
# It will be formatted as "%Y-%m-%d" or "%Y-%m-%d %H:%M:%S[.%f]"
return str(out)
@none_guard
def _sqlite_time_diff(lhs, rhs):
left = backend_utils.typecast_time(lhs)
right = backend_utils.typecast_time(rhs)
return (
(left.hour * 60 * 60 * 1000000) +
(left.minute * 60 * 1000000) +
(left.second * 1000000) +
(left.microsecond) -
(right.hour * 60 * 60 * 1000000) -
(right.minute * 60 * 1000000) -
(right.second * 1000000) -
(right.microsecond)
)
@none_guard
def _sqlite_timestamp_diff(lhs, rhs):
left = backend_utils.typecast_timestamp(lhs)
right = backend_utils.typecast_timestamp(rhs)
return duration_microseconds(left - right)
@none_guard
def _sqlite_regexp(re_pattern, re_string):
return bool(re.search(re_pattern, str(re_string)))
@none_guard
def _sqlite_lpad(text, length, fill_text):
if len(text) >= length:
return text[:length]
return (fill_text * length)[:length - len(text)] + text
@none_guard
def _sqlite_rpad(text, length, fill_text):
return (text + fill_text * length)[:length]
@none_guard
def _sqlite_json_contains(haystack, needle):
target, candidate = json.loads(haystack), json.loads(needle)
if isinstance(target, dict) and isinstance(candidate, dict):
return target.items() >= candidate.items()
return target == candidate
|
b59a391fbce56e7d0f3b9351ad900215c16e2aa21a8baf7593054f37d57881f2 | import datetime
import decimal
import uuid
from functools import lru_cache
from itertools import chain
from django.conf import settings
from django.core.exceptions import FieldError
from django.db import DatabaseError, NotSupportedError, models
from django.db.backends.base.operations import BaseDatabaseOperations
from django.db.models.expressions import Col
from django.utils import timezone
from django.utils.dateparse import parse_date, parse_datetime, parse_time
from django.utils.duration import duration_microseconds
from django.utils.functional import cached_property
class DatabaseOperations(BaseDatabaseOperations):
cast_char_field_without_max_length = 'text'
cast_data_types = {
'DateField': 'TEXT',
'DateTimeField': 'TEXT',
}
explain_prefix = 'EXPLAIN QUERY PLAN'
def bulk_batch_size(self, fields, objs):
"""
SQLite has a compile-time default (SQLITE_LIMIT_VARIABLE_NUMBER) of
999 variables per query.
If there's only a single field to insert, the limit is 500
(SQLITE_MAX_COMPOUND_SELECT).
"""
if len(fields) == 1:
return 500
elif len(fields) > 1:
return self.connection.features.max_query_params // len(fields)
else:
return len(objs)
def check_expression_support(self, expression):
bad_fields = (models.DateField, models.DateTimeField, models.TimeField)
bad_aggregates = (models.Sum, models.Avg, models.Variance, models.StdDev)
if isinstance(expression, bad_aggregates):
for expr in expression.get_source_expressions():
try:
output_field = expr.output_field
except (AttributeError, FieldError):
# Not every subexpression has an output_field which is fine
# to ignore.
pass
else:
if isinstance(output_field, bad_fields):
raise NotSupportedError(
'You cannot use Sum, Avg, StdDev, and Variance '
'aggregations on date/time fields in sqlite3 '
'since date/time is saved as text.'
)
if (
isinstance(expression, models.Aggregate) and
expression.distinct and
len(expression.source_expressions) > 1
):
raise NotSupportedError(
"SQLite doesn't support DISTINCT on aggregate functions "
"accepting multiple arguments."
)
def date_extract_sql(self, lookup_type, field_name):
"""
Support EXTRACT with a user-defined function django_date_extract()
that's registered in connect(). Use single quotes because this is a
string and could otherwise cause a collision with a field name.
"""
return "django_date_extract('%s', %s)" % (lookup_type.lower(), field_name)
def date_interval_sql(self, timedelta):
return str(duration_microseconds(timedelta))
def format_for_duration_arithmetic(self, sql):
"""Do nothing since formatting is handled in the custom function."""
return sql
def date_trunc_sql(self, lookup_type, field_name):
return "django_date_trunc('%s', %s)" % (lookup_type.lower(), field_name)
def time_trunc_sql(self, lookup_type, field_name):
return "django_time_trunc('%s', %s)" % (lookup_type.lower(), field_name)
def _convert_tznames_to_sql(self, tzname):
if settings.USE_TZ:
return "'%s'" % tzname, "'%s'" % self.connection.timezone_name
return 'NULL', 'NULL'
def datetime_cast_date_sql(self, field_name, tzname):
return 'django_datetime_cast_date(%s, %s, %s)' % (
field_name, *self._convert_tznames_to_sql(tzname),
)
def datetime_cast_time_sql(self, field_name, tzname):
return 'django_datetime_cast_time(%s, %s, %s)' % (
field_name, *self._convert_tznames_to_sql(tzname),
)
def datetime_extract_sql(self, lookup_type, field_name, tzname):
return "django_datetime_extract('%s', %s, %s, %s)" % (
lookup_type.lower(), field_name, *self._convert_tznames_to_sql(tzname),
)
def datetime_trunc_sql(self, lookup_type, field_name, tzname):
return "django_datetime_trunc('%s', %s, %s, %s)" % (
lookup_type.lower(), field_name, *self._convert_tznames_to_sql(tzname),
)
def time_extract_sql(self, lookup_type, field_name):
return "django_time_extract('%s', %s)" % (lookup_type.lower(), field_name)
def pk_default_value(self):
return "NULL"
def _quote_params_for_last_executed_query(self, params):
"""
Only for last_executed_query! Don't use this to execute SQL queries!
"""
# This function is limited both by SQLITE_LIMIT_VARIABLE_NUMBER (the
# number of parameters, default = 999) and SQLITE_MAX_COLUMN (the
# number of return values, default = 2000). Since Python's sqlite3
# module doesn't expose the get_limit() C API, assume the default
# limits are in effect and split the work in batches if needed.
BATCH_SIZE = 999
if len(params) > BATCH_SIZE:
results = ()
for index in range(0, len(params), BATCH_SIZE):
chunk = params[index:index + BATCH_SIZE]
results += self._quote_params_for_last_executed_query(chunk)
return results
sql = 'SELECT ' + ', '.join(['QUOTE(?)'] * len(params))
# Bypass Django's wrappers and use the underlying sqlite3 connection
# to avoid logging this query - it would trigger infinite recursion.
cursor = self.connection.connection.cursor()
# Native sqlite3 cursors cannot be used as context managers.
try:
return cursor.execute(sql, params).fetchone()
finally:
cursor.close()
def last_executed_query(self, cursor, sql, params):
# Python substitutes parameters in Modules/_sqlite/cursor.c with:
# pysqlite_statement_bind_parameters(self->statement, parameters, allow_8bit_chars);
# Unfortunately there is no way to reach self->statement from Python,
# so we quote and substitute parameters manually.
if params:
if isinstance(params, (list, tuple)):
params = self._quote_params_for_last_executed_query(params)
else:
values = tuple(params.values())
values = self._quote_params_for_last_executed_query(values)
params = dict(zip(params, values))
return sql % params
# For consistency with SQLiteCursorWrapper.execute(), just return sql
# when there are no parameters. See #13648 and #17158.
else:
return sql
def quote_name(self, name):
if name.startswith('"') and name.endswith('"'):
return name # Quoting once is enough.
return '"%s"' % name
def no_limit_value(self):
return -1
def __references_graph(self, table_name):
query = """
WITH tables AS (
SELECT %s name
UNION
SELECT sqlite_master.name
FROM sqlite_master
JOIN tables ON (sql REGEXP %s || tables.name || %s)
) SELECT name FROM tables;
"""
params = (
table_name,
r'(?i)\s+references\s+("|\')?',
r'("|\')?\s*\(',
)
with self.connection.cursor() as cursor:
results = cursor.execute(query, params)
return [row[0] for row in results.fetchall()]
@cached_property
def _references_graph(self):
# 512 is large enough to fit the ~330 tables (as of this writing) in
# Django's test suite.
return lru_cache(maxsize=512)(self.__references_graph)
def sql_flush(self, style, tables, *, reset_sequences=False, allow_cascade=False):
if tables and allow_cascade:
# Simulate TRUNCATE CASCADE by recursively collecting the tables
# referencing the tables to be flushed.
tables = set(chain.from_iterable(self._references_graph(table) for table in tables))
sql = ['%s %s %s;' % (
style.SQL_KEYWORD('DELETE'),
style.SQL_KEYWORD('FROM'),
style.SQL_FIELD(self.quote_name(table))
) for table in tables]
if reset_sequences:
sequences = [{'table': table} for table in tables]
sql.extend(self.sequence_reset_by_name_sql(style, sequences))
return sql
def sequence_reset_by_name_sql(self, style, sequences):
if not sequences:
return []
return [
'%s %s %s %s = 0 %s %s %s (%s);' % (
style.SQL_KEYWORD('UPDATE'),
style.SQL_TABLE(self.quote_name('sqlite_sequence')),
style.SQL_KEYWORD('SET'),
style.SQL_FIELD(self.quote_name('seq')),
style.SQL_KEYWORD('WHERE'),
style.SQL_FIELD(self.quote_name('name')),
style.SQL_KEYWORD('IN'),
', '.join([
"'%s'" % sequence_info['table'] for sequence_info in sequences
]),
),
]
def adapt_datetimefield_value(self, value):
if value is None:
return None
# Expression values are adapted by the database.
if hasattr(value, 'resolve_expression'):
return value
# SQLite doesn't support tz-aware datetimes
if timezone.is_aware(value):
if settings.USE_TZ:
value = timezone.make_naive(value, self.connection.timezone)
else:
raise ValueError("SQLite backend does not support timezone-aware datetimes when USE_TZ is False.")
return str(value)
def adapt_timefield_value(self, value):
if value is None:
return None
# Expression values are adapted by the database.
if hasattr(value, 'resolve_expression'):
return value
# SQLite doesn't support tz-aware datetimes
if timezone.is_aware(value):
raise ValueError("SQLite backend does not support timezone-aware times.")
return str(value)
def get_db_converters(self, expression):
converters = super().get_db_converters(expression)
internal_type = expression.output_field.get_internal_type()
if internal_type == 'DateTimeField':
converters.append(self.convert_datetimefield_value)
elif internal_type == 'DateField':
converters.append(self.convert_datefield_value)
elif internal_type == 'TimeField':
converters.append(self.convert_timefield_value)
elif internal_type == 'DecimalField':
converters.append(self.get_decimalfield_converter(expression))
elif internal_type == 'UUIDField':
converters.append(self.convert_uuidfield_value)
elif internal_type in ('NullBooleanField', 'BooleanField'):
converters.append(self.convert_booleanfield_value)
return converters
def convert_datetimefield_value(self, value, expression, connection):
if value is not None:
if not isinstance(value, datetime.datetime):
value = parse_datetime(value)
if settings.USE_TZ and not timezone.is_aware(value):
value = timezone.make_aware(value, self.connection.timezone)
return value
def convert_datefield_value(self, value, expression, connection):
if value is not None:
if not isinstance(value, datetime.date):
value = parse_date(value)
return value
def convert_timefield_value(self, value, expression, connection):
if value is not None:
if not isinstance(value, datetime.time):
value = parse_time(value)
return value
def get_decimalfield_converter(self, expression):
# SQLite stores only 15 significant digits. Digits coming from
# float inaccuracy must be removed.
create_decimal = decimal.Context(prec=15).create_decimal_from_float
if isinstance(expression, Col):
quantize_value = decimal.Decimal(1).scaleb(-expression.output_field.decimal_places)
def converter(value, expression, connection):
if value is not None:
return create_decimal(value).quantize(quantize_value, context=expression.output_field.context)
else:
def converter(value, expression, connection):
if value is not None:
return create_decimal(value)
return converter
def convert_uuidfield_value(self, value, expression, connection):
if value is not None:
value = uuid.UUID(value)
return value
def convert_booleanfield_value(self, value, expression, connection):
return bool(value) if value in (1, 0) else value
def bulk_insert_sql(self, fields, placeholder_rows):
return " UNION ALL ".join(
"SELECT %s" % ", ".join(row)
for row in placeholder_rows
)
def combine_expression(self, connector, sub_expressions):
# SQLite doesn't have a ^ operator, so use the user-defined POWER
# function that's registered in connect().
if connector == '^':
return 'POWER(%s)' % ','.join(sub_expressions)
elif connector == '#':
return 'BITXOR(%s)' % ','.join(sub_expressions)
return super().combine_expression(connector, sub_expressions)
def combine_duration_expression(self, connector, sub_expressions):
if connector not in ['+', '-']:
raise DatabaseError('Invalid connector for timedelta: %s.' % connector)
fn_params = ["'%s'" % connector] + sub_expressions
if len(fn_params) > 3:
raise ValueError('Too many params for timedelta operations.')
return "django_format_dtdelta(%s)" % ', '.join(fn_params)
def integer_field_range(self, internal_type):
# SQLite doesn't enforce any integer constraints
return (None, None)
def subtract_temporals(self, internal_type, lhs, rhs):
lhs_sql, lhs_params = lhs
rhs_sql, rhs_params = rhs
params = (*lhs_params, *rhs_params)
if internal_type == 'TimeField':
return 'django_time_diff(%s, %s)' % (lhs_sql, rhs_sql), params
return 'django_timestamp_diff(%s, %s)' % (lhs_sql, rhs_sql), params
def insert_statement(self, ignore_conflicts=False):
return 'INSERT OR IGNORE INTO' if ignore_conflicts else super().insert_statement(ignore_conflicts)
|
b0afd37a5b3ba6973495d2fb3fb39a1540053886ebdde41a6c6c5c6d4ee8c7f4 | import copy
from decimal import Decimal
from django.apps.registry import Apps
from django.db import NotSupportedError
from django.db.backends.base.schema import BaseDatabaseSchemaEditor
from django.db.backends.ddl_references import Statement
from django.db.backends.utils import strip_quotes
from django.db.models import UniqueConstraint
from django.db.transaction import atomic
class DatabaseSchemaEditor(BaseDatabaseSchemaEditor):
sql_delete_table = "DROP TABLE %(table)s"
sql_create_fk = None
sql_create_inline_fk = "REFERENCES %(to_table)s (%(to_column)s) DEFERRABLE INITIALLY DEFERRED"
sql_create_unique = "CREATE UNIQUE INDEX %(name)s ON %(table)s (%(columns)s)"
sql_delete_unique = "DROP INDEX %(name)s"
def __enter__(self):
# Some SQLite schema alterations need foreign key constraints to be
# disabled. Enforce it here for the duration of the schema edition.
if not self.connection.disable_constraint_checking():
raise NotSupportedError(
'SQLite schema editor cannot be used while foreign key '
'constraint checks are enabled. Make sure to disable them '
'before entering a transaction.atomic() context because '
'SQLite does not support disabling them in the middle of '
'a multi-statement transaction.'
)
return super().__enter__()
def __exit__(self, exc_type, exc_value, traceback):
self.connection.check_constraints()
super().__exit__(exc_type, exc_value, traceback)
self.connection.enable_constraint_checking()
def quote_value(self, value):
# The backend "mostly works" without this function and there are use
# cases for compiling Python without the sqlite3 libraries (e.g.
# security hardening).
try:
import sqlite3
value = sqlite3.adapt(value)
except ImportError:
pass
except sqlite3.ProgrammingError:
pass
# Manual emulation of SQLite parameter quoting
if isinstance(value, bool):
return str(int(value))
elif isinstance(value, (Decimal, float, int)):
return str(value)
elif isinstance(value, str):
return "'%s'" % value.replace("\'", "\'\'")
elif value is None:
return "NULL"
elif isinstance(value, (bytes, bytearray, memoryview)):
# Bytes are only allowed for BLOB fields, encoded as string
# literals containing hexadecimal data and preceded by a single "X"
# character.
return "X'%s'" % value.hex()
else:
raise ValueError("Cannot quote parameter value %r of type %s" % (value, type(value)))
def _is_referenced_by_fk_constraint(self, table_name, column_name=None, ignore_self=False):
"""
Return whether or not the provided table name is referenced by another
one. If `column_name` is specified, only references pointing to that
column are considered. If `ignore_self` is True, self-referential
constraints are ignored.
"""
with self.connection.cursor() as cursor:
for other_table in self.connection.introspection.get_table_list(cursor):
if ignore_self and other_table.name == table_name:
continue
constraints = self.connection.introspection._get_foreign_key_constraints(cursor, other_table.name)
for constraint in constraints.values():
constraint_table, constraint_column = constraint['foreign_key']
if (constraint_table == table_name and
(column_name is None or constraint_column == column_name)):
return True
return False
def alter_db_table(self, model, old_db_table, new_db_table, disable_constraints=True):
if (not self.connection.features.supports_atomic_references_rename and
disable_constraints and self._is_referenced_by_fk_constraint(old_db_table)):
if self.connection.in_atomic_block:
raise NotSupportedError((
'Renaming the %r table while in a transaction is not '
'supported on SQLite < 3.26 because it would break referential '
'integrity. Try adding `atomic = False` to the Migration class.'
) % old_db_table)
self.connection.enable_constraint_checking()
super().alter_db_table(model, old_db_table, new_db_table)
self.connection.disable_constraint_checking()
else:
super().alter_db_table(model, old_db_table, new_db_table)
def alter_field(self, model, old_field, new_field, strict=False):
old_field_name = old_field.name
table_name = model._meta.db_table
_, old_column_name = old_field.get_attname_column()
if (new_field.name != old_field_name and
not self.connection.features.supports_atomic_references_rename and
self._is_referenced_by_fk_constraint(table_name, old_column_name, ignore_self=True)):
if self.connection.in_atomic_block:
raise NotSupportedError((
'Renaming the %r.%r column while in a transaction is not '
'supported on SQLite < 3.26 because it would break referential '
'integrity. Try adding `atomic = False` to the Migration class.'
) % (model._meta.db_table, old_field_name))
with atomic(self.connection.alias):
super().alter_field(model, old_field, new_field, strict=strict)
# Follow SQLite's documented procedure for performing changes
# that don't affect the on-disk content.
# https://sqlite.org/lang_altertable.html#otheralter
with self.connection.cursor() as cursor:
schema_version = cursor.execute('PRAGMA schema_version').fetchone()[0]
cursor.execute('PRAGMA writable_schema = 1')
references_template = ' REFERENCES "%s" ("%%s") ' % table_name
new_column_name = new_field.get_attname_column()[1]
search = references_template % old_column_name
replacement = references_template % new_column_name
cursor.execute('UPDATE sqlite_master SET sql = replace(sql, %s, %s)', (search, replacement))
cursor.execute('PRAGMA schema_version = %d' % (schema_version + 1))
cursor.execute('PRAGMA writable_schema = 0')
# The integrity check will raise an exception and rollback
# the transaction if the sqlite_master updates corrupt the
# database.
cursor.execute('PRAGMA integrity_check')
# Perform a VACUUM to refresh the database representation from
# the sqlite_master table.
with self.connection.cursor() as cursor:
cursor.execute('VACUUM')
else:
super().alter_field(model, old_field, new_field, strict=strict)
def _remake_table(self, model, create_field=None, delete_field=None, alter_field=None):
"""
Shortcut to transform a model from old_model into new_model
This follows the correct procedure to perform non-rename or column
addition operations based on SQLite's documentation
https://www.sqlite.org/lang_altertable.html#caution
The essential steps are:
1. Create a table with the updated definition called "new__app_model"
2. Copy the data from the existing "app_model" table to the new table
3. Drop the "app_model" table
4. Rename the "new__app_model" table to "app_model"
5. Restore any index of the previous "app_model" table.
"""
# Self-referential fields must be recreated rather than copied from
# the old model to ensure their remote_field.field_name doesn't refer
# to an altered field.
def is_self_referential(f):
return f.is_relation and f.remote_field.model is model
# Work out the new fields dict / mapping
body = {
f.name: f.clone() if is_self_referential(f) else f
for f in model._meta.local_concrete_fields
}
# Since mapping might mix column names and default values,
# its values must be already quoted.
mapping = {f.column: self.quote_name(f.column) for f in model._meta.local_concrete_fields}
# This maps field names (not columns) for things like unique_together
rename_mapping = {}
# If any of the new or altered fields is introducing a new PK,
# remove the old one
restore_pk_field = None
if getattr(create_field, 'primary_key', False) or (
alter_field and getattr(alter_field[1], 'primary_key', False)):
for name, field in list(body.items()):
if field.primary_key:
field.primary_key = False
restore_pk_field = field
if field.auto_created:
del body[name]
del mapping[field.column]
# Add in any created fields
if create_field:
body[create_field.name] = create_field
# Choose a default and insert it into the copy map
if not create_field.many_to_many and create_field.concrete:
mapping[create_field.column] = self.quote_value(
self.effective_default(create_field)
)
# Add in any altered fields
if alter_field:
old_field, new_field = alter_field
body.pop(old_field.name, None)
mapping.pop(old_field.column, None)
body[new_field.name] = new_field
if old_field.null and not new_field.null:
case_sql = "coalesce(%(col)s, %(default)s)" % {
'col': self.quote_name(old_field.column),
'default': self.quote_value(self.effective_default(new_field))
}
mapping[new_field.column] = case_sql
else:
mapping[new_field.column] = self.quote_name(old_field.column)
rename_mapping[old_field.name] = new_field.name
# Remove any deleted fields
if delete_field:
del body[delete_field.name]
del mapping[delete_field.column]
# Remove any implicit M2M tables
if delete_field.many_to_many and delete_field.remote_field.through._meta.auto_created:
return self.delete_model(delete_field.remote_field.through)
# Work inside a new app registry
apps = Apps()
# Work out the new value of unique_together, taking renames into
# account
unique_together = [
[rename_mapping.get(n, n) for n in unique]
for unique in model._meta.unique_together
]
# Work out the new value for index_together, taking renames into
# account
index_together = [
[rename_mapping.get(n, n) for n in index]
for index in model._meta.index_together
]
indexes = model._meta.indexes
if delete_field:
indexes = [
index for index in indexes
if delete_field.name not in index.fields
]
constraints = list(model._meta.constraints)
# Provide isolated instances of the fields to the new model body so
# that the existing model's internals aren't interfered with when
# the dummy model is constructed.
body_copy = copy.deepcopy(body)
# Construct a new model with the new fields to allow self referential
# primary key to resolve to. This model won't ever be materialized as a
# table and solely exists for foreign key reference resolution purposes.
# This wouldn't be required if the schema editor was operating on model
# states instead of rendered models.
meta_contents = {
'app_label': model._meta.app_label,
'db_table': model._meta.db_table,
'unique_together': unique_together,
'index_together': index_together,
'indexes': indexes,
'constraints': constraints,
'apps': apps,
}
meta = type("Meta", (), meta_contents)
body_copy['Meta'] = meta
body_copy['__module__'] = model.__module__
type(model._meta.object_name, model.__bases__, body_copy)
# Construct a model with a renamed table name.
body_copy = copy.deepcopy(body)
meta_contents = {
'app_label': model._meta.app_label,
'db_table': 'new__%s' % strip_quotes(model._meta.db_table),
'unique_together': unique_together,
'index_together': index_together,
'indexes': indexes,
'constraints': constraints,
'apps': apps,
}
meta = type("Meta", (), meta_contents)
body_copy['Meta'] = meta
body_copy['__module__'] = model.__module__
new_model = type('New%s' % model._meta.object_name, model.__bases__, body_copy)
# Create a new table with the updated schema.
self.create_model(new_model)
# Copy data from the old table into the new table
self.execute("INSERT INTO %s (%s) SELECT %s FROM %s" % (
self.quote_name(new_model._meta.db_table),
', '.join(self.quote_name(x) for x in mapping),
', '.join(mapping.values()),
self.quote_name(model._meta.db_table),
))
# Delete the old table to make way for the new
self.delete_model(model, handle_autom2m=False)
# Rename the new table to take way for the old
self.alter_db_table(
new_model, new_model._meta.db_table, model._meta.db_table,
disable_constraints=False,
)
# Run deferred SQL on correct table
for sql in self.deferred_sql:
self.execute(sql)
self.deferred_sql = []
# Fix any PK-removed field
if restore_pk_field:
restore_pk_field.primary_key = True
def delete_model(self, model, handle_autom2m=True):
if handle_autom2m:
super().delete_model(model)
else:
# Delete the table (and only that)
self.execute(self.sql_delete_table % {
"table": self.quote_name(model._meta.db_table),
})
# Remove all deferred statements referencing the deleted table.
for sql in list(self.deferred_sql):
if isinstance(sql, Statement) and sql.references_table(model._meta.db_table):
self.deferred_sql.remove(sql)
def add_field(self, model, field):
"""
Create a field on a model. Usually involves adding a column, but may
involve adding a table instead (for M2M fields).
"""
# Special-case implicit M2M tables
if field.many_to_many and field.remote_field.through._meta.auto_created:
return self.create_model(field.remote_field.through)
self._remake_table(model, create_field=field)
def remove_field(self, model, field):
"""
Remove a field from a model. Usually involves deleting a column,
but for M2Ms may involve deleting a table.
"""
# M2M fields are a special case
if field.many_to_many:
# For implicit M2M tables, delete the auto-created table
if field.remote_field.through._meta.auto_created:
self.delete_model(field.remote_field.through)
# For explicit "through" M2M fields, do nothing
# For everything else, remake.
else:
# It might not actually have a column behind it
if field.db_parameters(connection=self.connection)['type'] is None:
return
self._remake_table(model, delete_field=field)
def _alter_field(self, model, old_field, new_field, old_type, new_type,
old_db_params, new_db_params, strict=False):
"""Perform a "physical" (non-ManyToMany) field update."""
# Use "ALTER TABLE ... RENAME COLUMN" if only the column name
# changed and there aren't any constraints.
if (self.connection.features.can_alter_table_rename_column and
old_field.column != new_field.column and
self.column_sql(model, old_field) == self.column_sql(model, new_field) and
not (old_field.remote_field and old_field.db_constraint or
new_field.remote_field and new_field.db_constraint)):
return self.execute(self._rename_field_sql(model._meta.db_table, old_field, new_field, new_type))
# Alter by remaking table
self._remake_table(model, alter_field=(old_field, new_field))
# Rebuild tables with FKs pointing to this field.
if new_field.unique and old_type != new_type:
related_models = set()
opts = new_field.model._meta
for remote_field in opts.related_objects:
# Ignore self-relationship since the table was already rebuilt.
if remote_field.related_model == model:
continue
if not remote_field.many_to_many:
if remote_field.field_name == new_field.name:
related_models.add(remote_field.related_model)
elif new_field.primary_key and remote_field.through._meta.auto_created:
related_models.add(remote_field.through)
if new_field.primary_key:
for many_to_many in opts.many_to_many:
# Ignore self-relationship since the table was already rebuilt.
if many_to_many.related_model == model:
continue
if many_to_many.remote_field.through._meta.auto_created:
related_models.add(many_to_many.remote_field.through)
for related_model in related_models:
self._remake_table(related_model)
def _alter_many_to_many(self, model, old_field, new_field, strict):
"""Alter M2Ms to repoint their to= endpoints."""
if old_field.remote_field.through._meta.db_table == new_field.remote_field.through._meta.db_table:
# The field name didn't change, but some options did; we have to propagate this altering.
self._remake_table(
old_field.remote_field.through,
alter_field=(
# We need the field that points to the target model, so we can tell alter_field to change it -
# this is m2m_reverse_field_name() (as opposed to m2m_field_name, which points to our model)
old_field.remote_field.through._meta.get_field(old_field.m2m_reverse_field_name()),
new_field.remote_field.through._meta.get_field(new_field.m2m_reverse_field_name()),
),
)
return
# Make a new through table
self.create_model(new_field.remote_field.through)
# Copy the data across
self.execute("INSERT INTO %s (%s) SELECT %s FROM %s" % (
self.quote_name(new_field.remote_field.through._meta.db_table),
', '.join([
"id",
new_field.m2m_column_name(),
new_field.m2m_reverse_name(),
]),
', '.join([
"id",
old_field.m2m_column_name(),
old_field.m2m_reverse_name(),
]),
self.quote_name(old_field.remote_field.through._meta.db_table),
))
# Delete the old through table
self.delete_model(old_field.remote_field.through)
def add_constraint(self, model, constraint):
if isinstance(constraint, UniqueConstraint) and constraint.condition:
super().add_constraint(model, constraint)
else:
self._remake_table(model)
def remove_constraint(self, model, constraint):
if isinstance(constraint, UniqueConstraint) and constraint.condition:
super().remove_constraint(model, constraint)
else:
self._remake_table(model)
|
e76d1bb2b6bab9db5c8f3e85024b069dfe68082b544b517c341482af70b98cd7 | import subprocess
from django.db.backends.base.client import BaseDatabaseClient
class DatabaseClient(BaseDatabaseClient):
executable_name = 'sqlite3'
def runshell(self, parameters):
# TODO: Remove str() when dropping support for PY37.
# args parameter accepts path-like objects on Windows since Python 3.8.
args = [self.executable_name,
str(self.connection.settings_dict['NAME'])]
args.extend(parameters)
subprocess.run(args, check=True)
|
7faa406b1d80e6177b761016097ba1bbe5cb35b22d74cddf5dd666a310d956ec | from itertools import chain
from django.utils.itercompat import is_iterable
class Tags:
"""
Built-in tags for internal checks.
"""
admin = 'admin'
async_support = 'async_support'
caches = 'caches'
compatibility = 'compatibility'
database = 'database'
models = 'models'
security = 'security'
signals = 'signals'
templates = 'templates'
translation = 'translation'
urls = 'urls'
class CheckRegistry:
def __init__(self):
self.registered_checks = set()
self.deployment_checks = set()
def register(self, check=None, *tags, **kwargs):
"""
Can be used as a function or a decorator. Register given function
`f` labeled with given `tags`. The function should receive **kwargs
and return list of Errors and Warnings.
Example::
registry = CheckRegistry()
@registry.register('mytag', 'anothertag')
def my_check(apps, **kwargs):
# ... perform checks and collect `errors` ...
return errors
# or
registry.register(my_check, 'mytag', 'anothertag')
"""
def inner(check):
check.tags = tags
checks = self.deployment_checks if kwargs.get('deploy') else self.registered_checks
checks.add(check)
return check
if callable(check):
return inner(check)
else:
if check:
tags += (check,)
return inner
def run_checks(self, app_configs=None, tags=None, include_deployment_checks=False, databases=None):
"""
Run all registered checks and return list of Errors and Warnings.
"""
errors = []
checks = self.get_checks(include_deployment_checks)
if tags is not None:
checks = [check for check in checks if not set(check.tags).isdisjoint(tags)]
for check in checks:
new_errors = check(app_configs=app_configs, databases=databases)
assert is_iterable(new_errors), (
"The function %r did not return a list. All functions registered "
"with the checks registry must return a list." % check)
errors.extend(new_errors)
return errors
def tag_exists(self, tag, include_deployment_checks=False):
return tag in self.tags_available(include_deployment_checks)
def tags_available(self, deployment_checks=False):
return set(chain.from_iterable(
check.tags for check in self.get_checks(deployment_checks)
))
def get_checks(self, include_deployment_checks=False):
checks = list(self.registered_checks)
if include_deployment_checks:
checks.extend(self.deployment_checks)
return checks
registry = CheckRegistry()
register = registry.register
run_checks = registry.run_checks
tag_exists = registry.tag_exists
|
04f9d2b581d87e106f48838d1b120a3f65e3fb4d678857270a3b5518bd0f1b60 | from .messages import (
CRITICAL, DEBUG, ERROR, INFO, WARNING, CheckMessage, Critical, Debug,
Error, Info, Warning,
)
from .registry import Tags, register, run_checks, tag_exists
# Import these to force registration of checks
import django.core.checks.async_checks # NOQA isort:skip
import django.core.checks.caches # NOQA isort:skip
import django.core.checks.database # NOQA isort:skip
import django.core.checks.model_checks # NOQA isort:skip
import django.core.checks.security.base # NOQA isort:skip
import django.core.checks.security.csrf # NOQA isort:skip
import django.core.checks.security.sessions # NOQA isort:skip
import django.core.checks.templates # NOQA isort:skip
import django.core.checks.translation # NOQA isort:skip
import django.core.checks.urls # NOQA isort:skip
__all__ = [
'CheckMessage',
'Debug', 'Info', 'Warning', 'Error', 'Critical',
'DEBUG', 'INFO', 'WARNING', 'ERROR', 'CRITICAL',
'register', 'run_checks', 'tag_exists', 'Tags',
]
|
b018fef28e039a91b940fcb5297817b59d056744fdc5d953e1704873bd309844 | from django.db import connections
from . import Tags, register
@register(Tags.database)
def check_database_backends(databases=None, **kwargs):
if databases is None:
return []
issues = []
for alias in databases:
conn = connections[alias]
issues.extend(conn.validation.check(**kwargs))
return issues
|
aed60f6ef0336546c1db739375f26002b3615460ab7a972d07cd8f2da15367d9 | import os
from . import Error, Tags, register
E001 = Error(
'You should not set the DJANGO_ALLOW_ASYNC_UNSAFE environment variable in '
'deployment. This disables async safety protection.',
id='async.E001',
)
@register(Tags.async_support, deploy=True)
def check_async_unsafe(app_configs, **kwargs):
if os.environ.get('DJANGO_ALLOW_ASYNC_UNSAFE'):
return [E001]
return []
|
1ef4766527861cf19bf3d33f621741c100e941ef6dcb917152f1a07390908ab3 | """
Base classes for writing management commands (named commands which can
be executed through ``django-admin`` or ``manage.py``).
"""
import os
import sys
from argparse import ArgumentParser, HelpFormatter
from io import TextIOBase
import django
from django.core import checks
from django.core.exceptions import ImproperlyConfigured
from django.core.management.color import color_style, no_style
from django.db import DEFAULT_DB_ALIAS, connections
class CommandError(Exception):
"""
Exception class indicating a problem while executing a management
command.
If this exception is raised during the execution of a management
command, it will be caught and turned into a nicely-printed error
message to the appropriate output stream (i.e., stderr); as a
result, raising this exception (with a sensible description of the
error) is the preferred way to indicate that something has gone
wrong in the execution of a command.
"""
def __init__(self, *args, returncode=1, **kwargs):
self.returncode = returncode
super().__init__(*args, **kwargs)
class SystemCheckError(CommandError):
"""
The system check framework detected unrecoverable errors.
"""
pass
class CommandParser(ArgumentParser):
"""
Customized ArgumentParser class to improve some error messages and prevent
SystemExit in several occasions, as SystemExit is unacceptable when a
command is called programmatically.
"""
def __init__(self, *, missing_args_message=None, called_from_command_line=None, **kwargs):
self.missing_args_message = missing_args_message
self.called_from_command_line = called_from_command_line
super().__init__(**kwargs)
def parse_args(self, args=None, namespace=None):
# Catch missing argument for a better error message
if (self.missing_args_message and
not (args or any(not arg.startswith('-') for arg in args))):
self.error(self.missing_args_message)
return super().parse_args(args, namespace)
def error(self, message):
if self.called_from_command_line:
super().error(message)
else:
raise CommandError("Error: %s" % message)
def handle_default_options(options):
"""
Include any default options that all commands should accept here
so that ManagementUtility can handle them before searching for
user commands.
"""
if options.settings:
os.environ['DJANGO_SETTINGS_MODULE'] = options.settings
if options.pythonpath:
sys.path.insert(0, options.pythonpath)
def no_translations(handle_func):
"""Decorator that forces a command to run with translations deactivated."""
def wrapped(*args, **kwargs):
from django.utils import translation
saved_locale = translation.get_language()
translation.deactivate_all()
try:
res = handle_func(*args, **kwargs)
finally:
if saved_locale is not None:
translation.activate(saved_locale)
return res
return wrapped
class DjangoHelpFormatter(HelpFormatter):
"""
Customized formatter so that command-specific arguments appear in the
--help output before arguments common to all commands.
"""
show_last = {
'--version', '--verbosity', '--traceback', '--settings', '--pythonpath',
'--no-color', '--force-color', '--skip-checks',
}
def _reordered_actions(self, actions):
return sorted(
actions,
key=lambda a: set(a.option_strings) & self.show_last != set()
)
def add_usage(self, usage, actions, *args, **kwargs):
super().add_usage(usage, self._reordered_actions(actions), *args, **kwargs)
def add_arguments(self, actions):
super().add_arguments(self._reordered_actions(actions))
class OutputWrapper(TextIOBase):
"""
Wrapper around stdout/stderr
"""
@property
def style_func(self):
return self._style_func
@style_func.setter
def style_func(self, style_func):
if style_func and self.isatty():
self._style_func = style_func
else:
self._style_func = lambda x: x
def __init__(self, out, ending='\n'):
self._out = out
self.style_func = None
self.ending = ending
def __getattr__(self, name):
return getattr(self._out, name)
def isatty(self):
return hasattr(self._out, 'isatty') and self._out.isatty()
def write(self, msg='', style_func=None, ending=None):
ending = self.ending if ending is None else ending
if ending and not msg.endswith(ending):
msg += ending
style_func = style_func or self.style_func
self._out.write(style_func(msg))
class BaseCommand:
"""
The base class from which all management commands ultimately
derive.
Use this class if you want access to all of the mechanisms which
parse the command-line arguments and work out what code to call in
response; if you don't need to change any of that behavior,
consider using one of the subclasses defined in this file.
If you are interested in overriding/customizing various aspects of
the command-parsing and -execution behavior, the normal flow works
as follows:
1. ``django-admin`` or ``manage.py`` loads the command class
and calls its ``run_from_argv()`` method.
2. The ``run_from_argv()`` method calls ``create_parser()`` to get
an ``ArgumentParser`` for the arguments, parses them, performs
any environment changes requested by options like
``pythonpath``, and then calls the ``execute()`` method,
passing the parsed arguments.
3. The ``execute()`` method attempts to carry out the command by
calling the ``handle()`` method with the parsed arguments; any
output produced by ``handle()`` will be printed to standard
output and, if the command is intended to produce a block of
SQL statements, will be wrapped in ``BEGIN`` and ``COMMIT``.
4. If ``handle()`` or ``execute()`` raised any exception (e.g.
``CommandError``), ``run_from_argv()`` will instead print an error
message to ``stderr``.
Thus, the ``handle()`` method is typically the starting point for
subclasses; many built-in commands and command types either place
all of their logic in ``handle()``, or perform some additional
parsing work in ``handle()`` and then delegate from it to more
specialized methods as needed.
Several attributes affect behavior at various steps along the way:
``help``
A short description of the command, which will be printed in
help messages.
``output_transaction``
A boolean indicating whether the command outputs SQL
statements; if ``True``, the output will automatically be
wrapped with ``BEGIN;`` and ``COMMIT;``. Default value is
``False``.
``requires_migrations_checks``
A boolean; if ``True``, the command prints a warning if the set of
migrations on disk don't match the migrations in the database.
``requires_system_checks``
A boolean; if ``True``, entire Django project will be checked for errors
prior to executing the command. Default value is ``True``.
To validate an individual application's models
rather than all applications' models, call
``self.check(app_configs)`` from ``handle()``, where ``app_configs``
is the list of application's configuration provided by the
app registry.
``stealth_options``
A tuple of any options the command uses which aren't defined by the
argument parser.
"""
# Metadata about this command.
help = ''
# Configuration shortcuts that alter various logic.
_called_from_command_line = False
output_transaction = False # Whether to wrap the output in a "BEGIN; COMMIT;"
requires_migrations_checks = False
requires_system_checks = True
# Arguments, common to all commands, which aren't defined by the argument
# parser.
base_stealth_options = ('stderr', 'stdout')
# Command-specific options not defined by the argument parser.
stealth_options = ()
def __init__(self, stdout=None, stderr=None, no_color=False, force_color=False):
self.stdout = OutputWrapper(stdout or sys.stdout)
self.stderr = OutputWrapper(stderr or sys.stderr)
if no_color and force_color:
raise CommandError("'no_color' and 'force_color' can't be used together.")
if no_color:
self.style = no_style()
else:
self.style = color_style(force_color)
self.stderr.style_func = self.style.ERROR
def get_version(self):
"""
Return the Django version, which should be correct for all built-in
Django commands. User-supplied commands can override this method to
return their own version.
"""
return django.get_version()
def create_parser(self, prog_name, subcommand, **kwargs):
"""
Create and return the ``ArgumentParser`` which will be used to
parse the arguments to this command.
"""
parser = CommandParser(
prog='%s %s' % (os.path.basename(prog_name), subcommand),
description=self.help or None,
formatter_class=DjangoHelpFormatter,
missing_args_message=getattr(self, 'missing_args_message', None),
called_from_command_line=getattr(self, '_called_from_command_line', None),
**kwargs
)
parser.add_argument('--version', action='version', version=self.get_version())
parser.add_argument(
'-v', '--verbosity', default=1,
type=int, choices=[0, 1, 2, 3],
help='Verbosity level; 0=minimal output, 1=normal output, 2=verbose output, 3=very verbose output',
)
parser.add_argument(
'--settings',
help=(
'The Python path to a settings module, e.g. '
'"myproject.settings.main". If this isn\'t provided, the '
'DJANGO_SETTINGS_MODULE environment variable will be used.'
),
)
parser.add_argument(
'--pythonpath',
help='A directory to add to the Python path, e.g. "/home/djangoprojects/myproject".',
)
parser.add_argument('--traceback', action='store_true', help='Raise on CommandError exceptions')
parser.add_argument(
'--no-color', action='store_true',
help="Don't colorize the command output.",
)
parser.add_argument(
'--force-color', action='store_true',
help='Force colorization of the command output.',
)
if self.requires_system_checks:
parser.add_argument(
'--skip-checks', action='store_true',
help='Skip system checks.',
)
self.add_arguments(parser)
return parser
def add_arguments(self, parser):
"""
Entry point for subclassed commands to add custom arguments.
"""
pass
def print_help(self, prog_name, subcommand):
"""
Print the help message for this command, derived from
``self.usage()``.
"""
parser = self.create_parser(prog_name, subcommand)
parser.print_help()
def run_from_argv(self, argv):
"""
Set up any environment changes requested (e.g., Python path
and Django settings), then run this command. If the
command raises a ``CommandError``, intercept it and print it sensibly
to stderr. If the ``--traceback`` option is present or the raised
``Exception`` is not ``CommandError``, raise it.
"""
self._called_from_command_line = True
parser = self.create_parser(argv[0], argv[1])
options = parser.parse_args(argv[2:])
cmd_options = vars(options)
# Move positional args out of options to mimic legacy optparse
args = cmd_options.pop('args', ())
handle_default_options(options)
try:
self.execute(*args, **cmd_options)
except CommandError as e:
if options.traceback:
raise
# SystemCheckError takes care of its own formatting.
if isinstance(e, SystemCheckError):
self.stderr.write(str(e), lambda x: x)
else:
self.stderr.write('%s: %s' % (e.__class__.__name__, e))
sys.exit(e.returncode)
finally:
try:
connections.close_all()
except ImproperlyConfigured:
# Ignore if connections aren't setup at this point (e.g. no
# configured settings).
pass
def execute(self, *args, **options):
"""
Try to execute this command, performing system checks if needed (as
controlled by the ``requires_system_checks`` attribute, except if
force-skipped).
"""
if options['force_color'] and options['no_color']:
raise CommandError("The --no-color and --force-color options can't be used together.")
if options['force_color']:
self.style = color_style(force_color=True)
elif options['no_color']:
self.style = no_style()
self.stderr.style_func = None
if options.get('stdout'):
self.stdout = OutputWrapper(options['stdout'])
if options.get('stderr'):
self.stderr = OutputWrapper(options['stderr'])
if self.requires_system_checks and not options['skip_checks']:
self.check()
if self.requires_migrations_checks:
self.check_migrations()
output = self.handle(*args, **options)
if output:
if self.output_transaction:
connection = connections[options.get('database', DEFAULT_DB_ALIAS)]
output = '%s\n%s\n%s' % (
self.style.SQL_KEYWORD(connection.ops.start_transaction_sql()),
output,
self.style.SQL_KEYWORD(connection.ops.end_transaction_sql()),
)
self.stdout.write(output)
return output
def check(self, app_configs=None, tags=None, display_num_errors=False,
include_deployment_checks=False, fail_level=checks.ERROR,
databases=None):
"""
Use the system check framework to validate entire Django project.
Raise CommandError for any serious message (error or critical errors).
If there are only light messages (like warnings), print them to stderr
and don't raise an exception.
"""
all_issues = checks.run_checks(
app_configs=app_configs,
tags=tags,
include_deployment_checks=include_deployment_checks,
databases=databases,
)
header, body, footer = "", "", ""
visible_issue_count = 0 # excludes silenced warnings
if all_issues:
debugs = [e for e in all_issues if e.level < checks.INFO and not e.is_silenced()]
infos = [e for e in all_issues if checks.INFO <= e.level < checks.WARNING and not e.is_silenced()]
warnings = [e for e in all_issues if checks.WARNING <= e.level < checks.ERROR and not e.is_silenced()]
errors = [e for e in all_issues if checks.ERROR <= e.level < checks.CRITICAL and not e.is_silenced()]
criticals = [e for e in all_issues if checks.CRITICAL <= e.level and not e.is_silenced()]
sorted_issues = [
(criticals, 'CRITICALS'),
(errors, 'ERRORS'),
(warnings, 'WARNINGS'),
(infos, 'INFOS'),
(debugs, 'DEBUGS'),
]
for issues, group_name in sorted_issues:
if issues:
visible_issue_count += len(issues)
formatted = (
self.style.ERROR(str(e))
if e.is_serious()
else self.style.WARNING(str(e))
for e in issues)
formatted = "\n".join(sorted(formatted))
body += '\n%s:\n%s\n' % (group_name, formatted)
if visible_issue_count:
header = "System check identified some issues:\n"
if display_num_errors:
if visible_issue_count:
footer += '\n'
footer += "System check identified %s (%s silenced)." % (
"no issues" if visible_issue_count == 0 else
"1 issue" if visible_issue_count == 1 else
"%s issues" % visible_issue_count,
len(all_issues) - visible_issue_count,
)
if any(e.is_serious(fail_level) and not e.is_silenced() for e in all_issues):
msg = self.style.ERROR("SystemCheckError: %s" % header) + body + footer
raise SystemCheckError(msg)
else:
msg = header + body + footer
if msg:
if visible_issue_count:
self.stderr.write(msg, lambda x: x)
else:
self.stdout.write(msg)
def check_migrations(self):
"""
Print a warning if the set of migrations on disk don't match the
migrations in the database.
"""
from django.db.migrations.executor import MigrationExecutor
try:
executor = MigrationExecutor(connections[DEFAULT_DB_ALIAS])
except ImproperlyConfigured:
# No databases are configured (or the dummy one)
return
plan = executor.migration_plan(executor.loader.graph.leaf_nodes())
if plan:
apps_waiting_migration = sorted({migration.app_label for migration, backwards in plan})
self.stdout.write(
self.style.NOTICE(
"\nYou have %(unapplied_migration_count)s unapplied migration(s). "
"Your project may not work properly until you apply the "
"migrations for app(s): %(apps_waiting_migration)s." % {
"unapplied_migration_count": len(plan),
"apps_waiting_migration": ", ".join(apps_waiting_migration),
}
)
)
self.stdout.write(self.style.NOTICE("Run 'python manage.py migrate' to apply them."))
def handle(self, *args, **options):
"""
The actual logic of the command. Subclasses must implement
this method.
"""
raise NotImplementedError('subclasses of BaseCommand must provide a handle() method')
class AppCommand(BaseCommand):
"""
A management command which takes one or more installed application labels
as arguments, and does something with each of them.
Rather than implementing ``handle()``, subclasses must implement
``handle_app_config()``, which will be called once for each application.
"""
missing_args_message = "Enter at least one application label."
def add_arguments(self, parser):
parser.add_argument('args', metavar='app_label', nargs='+', help='One or more application label.')
def handle(self, *app_labels, **options):
from django.apps import apps
try:
app_configs = [apps.get_app_config(app_label) for app_label in app_labels]
except (LookupError, ImportError) as e:
raise CommandError("%s. Are you sure your INSTALLED_APPS setting is correct?" % e)
output = []
for app_config in app_configs:
app_output = self.handle_app_config(app_config, **options)
if app_output:
output.append(app_output)
return '\n'.join(output)
def handle_app_config(self, app_config, **options):
"""
Perform the command's actions for app_config, an AppConfig instance
corresponding to an application label given on the command line.
"""
raise NotImplementedError(
"Subclasses of AppCommand must provide"
"a handle_app_config() method.")
class LabelCommand(BaseCommand):
"""
A management command which takes one or more arbitrary arguments
(labels) on the command line, and does something with each of
them.
Rather than implementing ``handle()``, subclasses must implement
``handle_label()``, which will be called once for each label.
If the arguments should be names of installed applications, use
``AppCommand`` instead.
"""
label = 'label'
missing_args_message = "Enter at least one %s." % label
def add_arguments(self, parser):
parser.add_argument('args', metavar=self.label, nargs='+')
def handle(self, *labels, **options):
output = []
for label in labels:
label_output = self.handle_label(label, **options)
if label_output:
output.append(label_output)
return '\n'.join(output)
def handle_label(self, label, **options):
"""
Perform the command's actions for ``label``, which will be the
string as given on the command line.
"""
raise NotImplementedError('subclasses of LabelCommand must provide a handle_label() method')
|
8d6c8570dd1e0cc1444fe846b0967416974a00d8bf146f9e9f676fc512ff9afc | import cgi
import mimetypes
import os
import posixpath
import shutil
import stat
import tempfile
from importlib import import_module
from urllib.request import urlretrieve
import django
from django.conf import settings
from django.core.management.base import BaseCommand, CommandError
from django.core.management.utils import handle_extensions
from django.template import Context, Engine
from django.utils import archive
from django.utils.version import get_docs_version
class TemplateCommand(BaseCommand):
"""
Copy either a Django application layout template or a Django project
layout template into the specified directory.
:param style: A color style object (see django.core.management.color).
:param app_or_project: The string 'app' or 'project'.
:param name: The name of the application or project.
:param directory: The directory to which the template should be copied.
:param options: The additional variables passed to project or app templates
"""
requires_system_checks = False
# The supported URL schemes
url_schemes = ['http', 'https', 'ftp']
# Rewrite the following suffixes when determining the target filename.
rewrite_template_suffixes = (
# Allow shipping invalid .py files without byte-compilation.
('.py-tpl', '.py'),
)
def add_arguments(self, parser):
parser.add_argument('name', help='Name of the application or project.')
parser.add_argument('directory', nargs='?', help='Optional destination directory')
parser.add_argument('--template', help='The path or URL to load the template from.')
parser.add_argument(
'--extension', '-e', dest='extensions',
action='append', default=['py'],
help='The file extension(s) to render (default: "py"). '
'Separate multiple extensions with commas, or use '
'-e multiple times.'
)
parser.add_argument(
'--name', '-n', dest='files',
action='append', default=[],
help='The file name(s) to render. Separate multiple file names '
'with commas, or use -n multiple times.'
)
def handle(self, app_or_project, name, target=None, **options):
self.app_or_project = app_or_project
self.a_or_an = 'an' if app_or_project == 'app' else 'a'
self.paths_to_remove = []
self.verbosity = options['verbosity']
self.validate_name(name)
# if some directory is given, make sure it's nicely expanded
if target is None:
top_dir = os.path.join(os.getcwd(), name)
try:
os.makedirs(top_dir)
except FileExistsError:
raise CommandError("'%s' already exists" % top_dir)
except OSError as e:
raise CommandError(e)
else:
if app_or_project == 'app':
self.validate_name(os.path.basename(target), 'directory')
top_dir = os.path.abspath(os.path.expanduser(target))
if not os.path.exists(top_dir):
raise CommandError("Destination directory '%s' does not "
"exist, please create it first." % top_dir)
extensions = tuple(handle_extensions(options['extensions']))
extra_files = []
for file in options['files']:
extra_files.extend(map(lambda x: x.strip(), file.split(',')))
if self.verbosity >= 2:
self.stdout.write(
'Rendering %s template files with extensions: %s'
% (app_or_project, ', '.join(extensions))
)
self.stdout.write(
'Rendering %s template files with filenames: %s'
% (app_or_project, ', '.join(extra_files))
)
base_name = '%s_name' % app_or_project
base_subdir = '%s_template' % app_or_project
base_directory = '%s_directory' % app_or_project
camel_case_name = 'camel_case_%s_name' % app_or_project
camel_case_value = ''.join(x for x in name.title() if x != '_')
context = Context({
**options,
base_name: name,
base_directory: top_dir,
camel_case_name: camel_case_value,
'docs_version': get_docs_version(),
'django_version': django.__version__,
}, autoescape=False)
# Setup a stub settings environment for template rendering
if not settings.configured:
settings.configure()
django.setup()
template_dir = self.handle_template(options['template'],
base_subdir)
prefix_length = len(template_dir) + 1
for root, dirs, files in os.walk(template_dir):
path_rest = root[prefix_length:]
relative_dir = path_rest.replace(base_name, name)
if relative_dir:
target_dir = os.path.join(top_dir, relative_dir)
os.makedirs(target_dir, exist_ok=True)
for dirname in dirs[:]:
if dirname.startswith('.') or dirname == '__pycache__':
dirs.remove(dirname)
for filename in files:
if filename.endswith(('.pyo', '.pyc', '.py.class')):
# Ignore some files as they cause various breakages.
continue
old_path = os.path.join(root, filename)
new_path = os.path.join(
top_dir, relative_dir, filename.replace(base_name, name)
)
for old_suffix, new_suffix in self.rewrite_template_suffixes:
if new_path.endswith(old_suffix):
new_path = new_path[:-len(old_suffix)] + new_suffix
break # Only rewrite once
if os.path.exists(new_path):
raise CommandError(
"%s already exists. Overlaying %s %s into an existing "
"directory won't replace conflicting files." % (
new_path, self.a_or_an, app_or_project,
)
)
# Only render the Python files, as we don't want to
# accidentally render Django templates files
if new_path.endswith(extensions) or filename in extra_files:
with open(old_path, encoding='utf-8') as template_file:
content = template_file.read()
template = Engine().from_string(content)
content = template.render(context)
with open(new_path, 'w', encoding='utf-8') as new_file:
new_file.write(content)
else:
shutil.copyfile(old_path, new_path)
if self.verbosity >= 2:
self.stdout.write('Creating %s' % new_path)
try:
shutil.copymode(old_path, new_path)
self.make_writeable(new_path)
except OSError:
self.stderr.write(
"Notice: Couldn't set permission bits on %s. You're "
"probably using an uncommon filesystem setup. No "
"problem." % new_path, self.style.NOTICE)
if self.paths_to_remove:
if self.verbosity >= 2:
self.stdout.write('Cleaning up temporary files.')
for path_to_remove in self.paths_to_remove:
if os.path.isfile(path_to_remove):
os.remove(path_to_remove)
else:
shutil.rmtree(path_to_remove)
def handle_template(self, template, subdir):
"""
Determine where the app or project templates are.
Use django.__path__[0] as the default because the Django install
directory isn't known.
"""
if template is None:
return os.path.join(django.__path__[0], 'conf', subdir)
else:
if template.startswith('file://'):
template = template[7:]
expanded_template = os.path.expanduser(template)
expanded_template = os.path.normpath(expanded_template)
if os.path.isdir(expanded_template):
return expanded_template
if self.is_url(template):
# downloads the file and returns the path
absolute_path = self.download(template)
else:
absolute_path = os.path.abspath(expanded_template)
if os.path.exists(absolute_path):
return self.extract(absolute_path)
raise CommandError("couldn't handle %s template %s." %
(self.app_or_project, template))
def validate_name(self, name, name_or_dir='name'):
if name is None:
raise CommandError('you must provide {an} {app} name'.format(
an=self.a_or_an,
app=self.app_or_project,
))
# Check it's a valid directory name.
if not name.isidentifier():
raise CommandError(
"'{name}' is not a valid {app} {type}. Please make sure the "
"{type} is a valid identifier.".format(
name=name,
app=self.app_or_project,
type=name_or_dir,
)
)
# Check it cannot be imported.
try:
import_module(name)
except ImportError:
pass
else:
raise CommandError(
"'{name}' conflicts with the name of an existing Python "
"module and cannot be used as {an} {app} {type}. Please try "
"another {type}.".format(
name=name,
an=self.a_or_an,
app=self.app_or_project,
type=name_or_dir,
)
)
def download(self, url):
"""
Download the given URL and return the file name.
"""
def cleanup_url(url):
tmp = url.rstrip('/')
filename = tmp.split('/')[-1]
if url.endswith('/'):
display_url = tmp + '/'
else:
display_url = url
return filename, display_url
prefix = 'django_%s_template_' % self.app_or_project
tempdir = tempfile.mkdtemp(prefix=prefix, suffix='_download')
self.paths_to_remove.append(tempdir)
filename, display_url = cleanup_url(url)
if self.verbosity >= 2:
self.stdout.write('Downloading %s' % display_url)
try:
the_path, info = urlretrieve(url, os.path.join(tempdir, filename))
except OSError as e:
raise CommandError("couldn't download URL %s to %s: %s" %
(url, filename, e))
used_name = the_path.split('/')[-1]
# Trying to get better name from response headers
content_disposition = info.get('content-disposition')
if content_disposition:
_, params = cgi.parse_header(content_disposition)
guessed_filename = params.get('filename') or used_name
else:
guessed_filename = used_name
# Falling back to content type guessing
ext = self.splitext(guessed_filename)[1]
content_type = info.get('content-type')
if not ext and content_type:
ext = mimetypes.guess_extension(content_type)
if ext:
guessed_filename += ext
# Move the temporary file to a filename that has better
# chances of being recognized by the archive utils
if used_name != guessed_filename:
guessed_path = os.path.join(tempdir, guessed_filename)
shutil.move(the_path, guessed_path)
return guessed_path
# Giving up
return the_path
def splitext(self, the_path):
"""
Like os.path.splitext, but takes off .tar, too
"""
base, ext = posixpath.splitext(the_path)
if base.lower().endswith('.tar'):
ext = base[-4:] + ext
base = base[:-4]
return base, ext
def extract(self, filename):
"""
Extract the given file to a temporarily and return
the path of the directory with the extracted content.
"""
prefix = 'django_%s_template_' % self.app_or_project
tempdir = tempfile.mkdtemp(prefix=prefix, suffix='_extract')
self.paths_to_remove.append(tempdir)
if self.verbosity >= 2:
self.stdout.write('Extracting %s' % filename)
try:
archive.extract(filename, tempdir)
return tempdir
except (archive.ArchiveException, OSError) as e:
raise CommandError("couldn't extract file %s to %s: %s" %
(filename, tempdir, e))
def is_url(self, template):
"""Return True if the name looks like a URL."""
if ':' not in template:
return False
scheme = template.split(':', 1)[0].lower()
return scheme in self.url_schemes
def make_writeable(self, filename):
"""
Make sure that the file is writeable.
Useful if our source is read-only.
"""
if not os.access(filename, os.W_OK):
st = os.stat(filename)
new_permissions = stat.S_IMODE(st.st_mode) | stat.S_IWUSR
os.chmod(filename, new_permissions)
|
79a7c8766edd30fe2e3f0ba3706b4d640e799a70741fd5f80191f853b42a7fe4 | from django.apps import apps
from django.db import models
def sql_flush(style, connection, only_django=False, reset_sequences=True, allow_cascade=False):
"""
Return a list of the SQL statements used to flush the database.
If only_django is True, only include the table names that have associated
Django models and are in INSTALLED_APPS .
"""
if only_django:
tables = connection.introspection.django_table_names(only_existing=True, include_views=False)
else:
tables = connection.introspection.table_names(include_views=False)
return connection.ops.sql_flush(
style,
tables,
reset_sequences=reset_sequences,
allow_cascade=allow_cascade,
)
def emit_pre_migrate_signal(verbosity, interactive, db, **kwargs):
# Emit the pre_migrate signal for every application.
for app_config in apps.get_app_configs():
if app_config.models_module is None:
continue
if verbosity >= 2:
print("Running pre-migrate handlers for application %s" % app_config.label)
models.signals.pre_migrate.send(
sender=app_config,
app_config=app_config,
verbosity=verbosity,
interactive=interactive,
using=db,
**kwargs
)
def emit_post_migrate_signal(verbosity, interactive, db, **kwargs):
# Emit the post_migrate signal for every application.
for app_config in apps.get_app_configs():
if app_config.models_module is None:
continue
if verbosity >= 2:
print("Running post-migrate handlers for application %s" % app_config.label)
models.signals.post_migrate.send(
sender=app_config,
app_config=app_config,
verbosity=verbosity,
interactive=interactive,
using=db,
**kwargs
)
|
34c72b5e73db8c6d3a0456d283bb9ab804a2192e3854ed0576a04365fdbbb724 | """
Sets up the terminal color scheme.
"""
import functools
import os
import sys
from django.utils import termcolors
def supports_color():
"""
Return True if the running system's terminal supports color,
and False otherwise.
"""
supported_platform = sys.platform != 'win32' or 'ANSICON' in os.environ
# isatty is not always implemented, #6223.
is_a_tty = hasattr(sys.stdout, 'isatty') and sys.stdout.isatty()
return supported_platform and is_a_tty
class Style:
pass
def make_style(config_string=''):
"""
Create a Style object from the given config_string.
If config_string is empty django.utils.termcolors.DEFAULT_PALETTE is used.
"""
style = Style()
color_settings = termcolors.parse_color_setting(config_string)
# The nocolor palette has all available roles.
# Use that palette as the basis for populating
# the palette as defined in the environment.
for role in termcolors.PALETTES[termcolors.NOCOLOR_PALETTE]:
if color_settings:
format = color_settings.get(role, {})
style_func = termcolors.make_style(**format)
else:
def style_func(x):
return x
setattr(style, role, style_func)
# For backwards compatibility,
# set style for ERROR_OUTPUT == ERROR
style.ERROR_OUTPUT = style.ERROR
return style
@functools.lru_cache(maxsize=None)
def no_style():
"""
Return a Style object with no color scheme.
"""
return make_style('nocolor')
def color_style(force_color=False):
"""
Return a Style object from the Django color scheme.
"""
if not force_color and not supports_color():
return no_style()
return make_style(os.environ.get('DJANGO_COLORS', ''))
|
098740283d0632dfbdfbb455d9ed2cdaf299c0fb0f8f0d6fcb2598f1527aba8c | """
Caching framework.
This package defines set of cache backends that all conform to a simple API.
In a nutshell, a cache is a set of values -- which can be any object that
may be pickled -- identified by string keys. For the complete API, see
the abstract BaseCache class in django.core.cache.backends.base.
Client code should use the `cache` variable defined here to access the default
cache backend and look up non-default cache backends in the `caches` dict-like
object.
See docs/topics/cache.txt for information on the public API.
"""
from asgiref.local import Local
from django.conf import settings
from django.core import signals
from django.core.cache.backends.base import (
BaseCache, CacheKeyWarning, InvalidCacheBackendError,
)
from django.utils.module_loading import import_string
__all__ = [
'cache', 'caches', 'DEFAULT_CACHE_ALIAS', 'InvalidCacheBackendError',
'CacheKeyWarning', 'BaseCache',
]
DEFAULT_CACHE_ALIAS = 'default'
def _create_cache(backend, **kwargs):
try:
# Try to get the CACHES entry for the given backend name first
try:
conf = settings.CACHES[backend]
except KeyError:
try:
# Trying to import the given backend, in case it's a dotted path
import_string(backend)
except ImportError as e:
raise InvalidCacheBackendError("Could not find backend '%s': %s" % (
backend, e))
location = kwargs.pop('LOCATION', '')
params = kwargs
else:
params = {**conf, **kwargs}
backend = params.pop('BACKEND')
location = params.pop('LOCATION', '')
backend_cls = import_string(backend)
except ImportError as e:
raise InvalidCacheBackendError(
"Could not find backend '%s': %s" % (backend, e))
return backend_cls(location, params)
class CacheHandler:
"""
A Cache Handler to manage access to Cache instances.
Ensure only one instance of each alias exists per thread.
"""
def __init__(self):
self._caches = Local()
def __getitem__(self, alias):
try:
return self._caches.caches[alias]
except AttributeError:
self._caches.caches = {}
except KeyError:
pass
if alias not in settings.CACHES:
raise InvalidCacheBackendError(
"Could not find config for '%s' in settings.CACHES" % alias
)
cache = _create_cache(alias)
self._caches.caches[alias] = cache
return cache
def all(self):
return getattr(self._caches, 'caches', {}).values()
caches = CacheHandler()
class DefaultCacheProxy:
"""
Proxy access to the default Cache object's attributes.
This allows the legacy `cache` object to be thread-safe using the new
``caches`` API.
"""
def __getattr__(self, name):
return getattr(caches[DEFAULT_CACHE_ALIAS], name)
def __setattr__(self, name, value):
return setattr(caches[DEFAULT_CACHE_ALIAS], name, value)
def __delattr__(self, name):
return delattr(caches[DEFAULT_CACHE_ALIAS], name)
def __contains__(self, key):
return key in caches[DEFAULT_CACHE_ALIAS]
def __eq__(self, other):
return caches[DEFAULT_CACHE_ALIAS] == other
cache = DefaultCacheProxy()
def close_caches(**kwargs):
# Some caches -- python-memcached in particular -- need to do a cleanup at the
# end of a request cycle. If not implemented in a particular backend
# cache.close is a no-op
for cache in caches.all():
cache.close()
signals.request_finished.connect(close_caches)
|
2d81617a6fa5609228d178385e0ba76df369e944d6ee2ae3580527d1fb16c011 | """
Interfaces for serializing Django objects.
Usage::
from django.core import serializers
json = serializers.serialize("json", some_queryset)
objects = list(serializers.deserialize("json", json))
To add your own serializers, use the SERIALIZATION_MODULES setting::
SERIALIZATION_MODULES = {
"csv": "path.to.csv.serializer",
"txt": "path.to.txt.serializer",
}
"""
import importlib
from django.apps import apps
from django.conf import settings
from django.core.serializers.base import SerializerDoesNotExist
# Built-in serializers
BUILTIN_SERIALIZERS = {
"xml": "django.core.serializers.xml_serializer",
"python": "django.core.serializers.python",
"json": "django.core.serializers.json",
"yaml": "django.core.serializers.pyyaml",
}
_serializers = {}
class BadSerializer:
"""
Stub serializer to hold exception raised during registration
This allows the serializer registration to cache serializers and if there
is an error raised in the process of creating a serializer it will be
raised and passed along to the caller when the serializer is used.
"""
internal_use_only = False
def __init__(self, exception):
self.exception = exception
def __call__(self, *args, **kwargs):
raise self.exception
def register_serializer(format, serializer_module, serializers=None):
"""Register a new serializer.
``serializer_module`` should be the fully qualified module name
for the serializer.
If ``serializers`` is provided, the registration will be added
to the provided dictionary.
If ``serializers`` is not provided, the registration will be made
directly into the global register of serializers. Adding serializers
directly is not a thread-safe operation.
"""
if serializers is None and not _serializers:
_load_serializers()
try:
module = importlib.import_module(serializer_module)
except ImportError as exc:
bad_serializer = BadSerializer(exc)
module = type('BadSerializerModule', (), {
'Deserializer': bad_serializer,
'Serializer': bad_serializer,
})
if serializers is None:
_serializers[format] = module
else:
serializers[format] = module
def unregister_serializer(format):
"Unregister a given serializer. This is not a thread-safe operation."
if not _serializers:
_load_serializers()
if format not in _serializers:
raise SerializerDoesNotExist(format)
del _serializers[format]
def get_serializer(format):
if not _serializers:
_load_serializers()
if format not in _serializers:
raise SerializerDoesNotExist(format)
return _serializers[format].Serializer
def get_serializer_formats():
if not _serializers:
_load_serializers()
return list(_serializers)
def get_public_serializer_formats():
if not _serializers:
_load_serializers()
return [k for k, v in _serializers.items() if not v.Serializer.internal_use_only]
def get_deserializer(format):
if not _serializers:
_load_serializers()
if format not in _serializers:
raise SerializerDoesNotExist(format)
return _serializers[format].Deserializer
def serialize(format, queryset, **options):
"""
Serialize a queryset (or any iterator that returns database objects) using
a certain serializer.
"""
s = get_serializer(format)()
s.serialize(queryset, **options)
return s.getvalue()
def deserialize(format, stream_or_string, **options):
"""
Deserialize a stream or a string. Return an iterator that yields ``(obj,
m2m_relation_dict)``, where ``obj`` is an instantiated -- but *unsaved* --
object, and ``m2m_relation_dict`` is a dictionary of ``{m2m_field_name :
list_of_related_objects}``.
"""
d = get_deserializer(format)
return d(stream_or_string, **options)
def _load_serializers():
"""
Register built-in and settings-defined serializers. This is done lazily so
that user code has a chance to (e.g.) set up custom settings without
needing to be careful of import order.
"""
global _serializers
serializers = {}
for format in BUILTIN_SERIALIZERS:
register_serializer(format, BUILTIN_SERIALIZERS[format], serializers)
if hasattr(settings, "SERIALIZATION_MODULES"):
for format in settings.SERIALIZATION_MODULES:
register_serializer(format, settings.SERIALIZATION_MODULES[format], serializers)
_serializers = serializers
def sort_dependencies(app_list, allow_cycles=False):
"""Sort a list of (app_config, models) pairs into a single list of models.
The single list of models is sorted so that any model with a natural key
is serialized before a normal model, and any model with a natural key
dependency has it's dependencies serialized first.
If allow_cycles is True, return the best-effort ordering that will respect
most of dependencies but ignore some of them to break the cycles.
"""
# Process the list of models, and get the list of dependencies
model_dependencies = []
models = set()
for app_config, model_list in app_list:
if model_list is None:
model_list = app_config.get_models()
for model in model_list:
models.add(model)
# Add any explicitly defined dependencies
if hasattr(model, 'natural_key'):
deps = getattr(model.natural_key, 'dependencies', [])
if deps:
deps = [apps.get_model(dep) for dep in deps]
else:
deps = []
# Now add a dependency for any FK relation with a model that
# defines a natural key
for field in model._meta.fields:
if field.remote_field:
rel_model = field.remote_field.model
if hasattr(rel_model, 'natural_key') and rel_model != model:
deps.append(rel_model)
# Also add a dependency for any simple M2M relation with a model
# that defines a natural key. M2M relations with explicit through
# models don't count as dependencies.
for field in model._meta.many_to_many:
if field.remote_field.through._meta.auto_created:
rel_model = field.remote_field.model
if hasattr(rel_model, 'natural_key') and rel_model != model:
deps.append(rel_model)
model_dependencies.append((model, deps))
model_dependencies.reverse()
# Now sort the models to ensure that dependencies are met. This
# is done by repeatedly iterating over the input list of models.
# If all the dependencies of a given model are in the final list,
# that model is promoted to the end of the final list. This process
# continues until the input list is empty, or we do a full iteration
# over the input models without promoting a model to the final list.
# If we do a full iteration without a promotion, that means there are
# circular dependencies in the list.
model_list = []
while model_dependencies:
skipped = []
changed = False
while model_dependencies:
model, deps = model_dependencies.pop()
# If all of the models in the dependency list are either already
# on the final model list, or not on the original serialization list,
# then we've found another model with all it's dependencies satisfied.
if all(d not in models or d in model_list for d in deps):
model_list.append(model)
changed = True
else:
skipped.append((model, deps))
if not changed:
if allow_cycles:
# If cycles are allowed, add the last skipped model and ignore
# its dependencies. This could be improved by some graph
# analysis to ignore as few dependencies as possible.
model, _ = skipped.pop()
model_list.append(model)
else:
raise RuntimeError(
"Can't resolve dependencies for %s in serialized app list."
% ', '.join(
model._meta.label
for model, deps in sorted(skipped, key=lambda obj: obj[0].__name__)
),
)
model_dependencies = skipped
return model_list
|
a5e59151bbe3173acc2a5ef0745e60b9cc86ebc7a7f03bccaca29df58faa341f | """
Serialize data to/from JSON
"""
import datetime
import decimal
import json
import uuid
from django.core.serializers.base import DeserializationError
from django.core.serializers.python import (
Deserializer as PythonDeserializer, Serializer as PythonSerializer,
)
from django.utils.duration import duration_iso_string
from django.utils.functional import Promise
from django.utils.timezone import is_aware
class Serializer(PythonSerializer):
"""Convert a queryset to JSON."""
internal_use_only = False
def _init_options(self):
self._current = None
self.json_kwargs = self.options.copy()
self.json_kwargs.pop('stream', None)
self.json_kwargs.pop('fields', None)
if self.options.get('indent'):
# Prevent trailing spaces
self.json_kwargs['separators'] = (',', ': ')
self.json_kwargs.setdefault('cls', DjangoJSONEncoder)
self.json_kwargs.setdefault('ensure_ascii', False)
def start_serialization(self):
self._init_options()
self.stream.write("[")
def end_serialization(self):
if self.options.get("indent"):
self.stream.write("\n")
self.stream.write("]")
if self.options.get("indent"):
self.stream.write("\n")
def end_object(self, obj):
# self._current has the field data
indent = self.options.get("indent")
if not self.first:
self.stream.write(",")
if not indent:
self.stream.write(" ")
if indent:
self.stream.write("\n")
json.dump(self.get_dump_object(obj), self.stream, **self.json_kwargs)
self._current = None
def getvalue(self):
# Grandparent super
return super(PythonSerializer, self).getvalue()
def Deserializer(stream_or_string, **options):
"""Deserialize a stream or string of JSON data."""
if not isinstance(stream_or_string, (bytes, str)):
stream_or_string = stream_or_string.read()
if isinstance(stream_or_string, bytes):
stream_or_string = stream_or_string.decode()
try:
objects = json.loads(stream_or_string)
yield from PythonDeserializer(objects, **options)
except (GeneratorExit, DeserializationError):
raise
except Exception as exc:
raise DeserializationError() from exc
class DjangoJSONEncoder(json.JSONEncoder):
"""
JSONEncoder subclass that knows how to encode date/time, decimal types, and
UUIDs.
"""
def default(self, o):
# See "Date Time String Format" in the ECMA-262 specification.
if isinstance(o, datetime.datetime):
r = o.isoformat()
if o.microsecond:
r = r[:23] + r[26:]
if r.endswith('+00:00'):
r = r[:-6] + 'Z'
return r
elif isinstance(o, datetime.date):
return o.isoformat()
elif isinstance(o, datetime.time):
if is_aware(o):
raise ValueError("JSON can't represent timezone-aware times.")
r = o.isoformat()
if o.microsecond:
r = r[:12]
return r
elif isinstance(o, datetime.timedelta):
return duration_iso_string(o)
elif isinstance(o, (decimal.Decimal, uuid.UUID, Promise)):
return str(o)
else:
return super().default(o)
|
5f521beb5764302d4abf469836cefa8cd703ca6df84be405934e1db3a7690257 | """
YAML serializer.
Requires PyYaml (https://pyyaml.org/), but that's checked for in __init__.
"""
import collections
import decimal
from io import StringIO
import yaml
from django.core.serializers.base import DeserializationError
from django.core.serializers.python import (
Deserializer as PythonDeserializer, Serializer as PythonSerializer,
)
from django.db import models
# Use the C (faster) implementation if possible
try:
from yaml import CSafeLoader as SafeLoader
from yaml import CSafeDumper as SafeDumper
except ImportError:
from yaml import SafeLoader, SafeDumper
class DjangoSafeDumper(SafeDumper):
def represent_decimal(self, data):
return self.represent_scalar('tag:yaml.org,2002:str', str(data))
def represent_ordered_dict(self, data):
return self.represent_mapping('tag:yaml.org,2002:map', data.items())
DjangoSafeDumper.add_representer(decimal.Decimal, DjangoSafeDumper.represent_decimal)
DjangoSafeDumper.add_representer(collections.OrderedDict, DjangoSafeDumper.represent_ordered_dict)
# Workaround to represent dictionaries in insertion order.
# See https://github.com/yaml/pyyaml/pull/143.
DjangoSafeDumper.add_representer(dict, DjangoSafeDumper.represent_ordered_dict)
class Serializer(PythonSerializer):
"""Convert a queryset to YAML."""
internal_use_only = False
def handle_field(self, obj, field):
# A nasty special case: base YAML doesn't support serialization of time
# types (as opposed to dates or datetimes, which it does support). Since
# we want to use the "safe" serializer for better interoperability, we
# need to do something with those pesky times. Converting 'em to strings
# isn't perfect, but it's better than a "!!python/time" type which would
# halt deserialization under any other language.
if isinstance(field, models.TimeField) and getattr(obj, field.name) is not None:
self._current[field.name] = str(getattr(obj, field.name))
else:
super().handle_field(obj, field)
def end_serialization(self):
self.options.setdefault('allow_unicode', True)
yaml.dump(self.objects, self.stream, Dumper=DjangoSafeDumper, **self.options)
def getvalue(self):
# Grandparent super
return super(PythonSerializer, self).getvalue()
def Deserializer(stream_or_string, **options):
"""Deserialize a stream or string of YAML data."""
if isinstance(stream_or_string, bytes):
stream_or_string = stream_or_string.decode()
if isinstance(stream_or_string, str):
stream = StringIO(stream_or_string)
else:
stream = stream_or_string
try:
yield from PythonDeserializer(yaml.load(stream, Loader=SafeLoader), **options)
except (GeneratorExit, DeserializationError):
raise
except Exception as exc:
raise DeserializationError() from exc
|
4bb4938be778ffeda7a7f8ea8dd659a58b94ff67a7adf3e71824d9bec4ee61da | import logging
import sys
import tempfile
import traceback
from asgiref.sync import sync_to_async
from django.conf import settings
from django.core import signals
from django.core.exceptions import RequestAborted, RequestDataTooBig
from django.core.handlers import base
from django.http import (
FileResponse, HttpRequest, HttpResponse, HttpResponseBadRequest,
HttpResponseServerError, QueryDict, parse_cookie,
)
from django.urls import set_script_prefix
from django.utils.functional import cached_property
logger = logging.getLogger('django.request')
class ASGIRequest(HttpRequest):
"""
Custom request subclass that decodes from an ASGI-standard request dict
and wraps request body handling.
"""
# Number of seconds until a Request gives up on trying to read a request
# body and aborts.
body_receive_timeout = 60
def __init__(self, scope, body_file):
self.scope = scope
self._post_parse_error = False
self._read_started = False
self.resolver_match = None
self.script_name = self.scope.get('root_path', '')
if self.script_name and scope['path'].startswith(self.script_name):
# TODO: Better is-prefix checking, slash handling?
self.path_info = scope['path'][len(self.script_name):]
else:
self.path_info = scope['path']
# The Django path is different from ASGI scope path args, it should
# combine with script name.
if self.script_name:
self.path = '%s/%s' % (
self.script_name.rstrip('/'),
self.path_info.replace('/', '', 1),
)
else:
self.path = scope['path']
# HTTP basics.
self.method = self.scope['method'].upper()
# Ensure query string is encoded correctly.
query_string = self.scope.get('query_string', '')
if isinstance(query_string, bytes):
query_string = query_string.decode()
self.META = {
'REQUEST_METHOD': self.method,
'QUERY_STRING': query_string,
'SCRIPT_NAME': self.script_name,
'PATH_INFO': self.path_info,
# WSGI-expecting code will need these for a while
'wsgi.multithread': True,
'wsgi.multiprocess': True,
}
if self.scope.get('client'):
self.META['REMOTE_ADDR'] = self.scope['client'][0]
self.META['REMOTE_HOST'] = self.META['REMOTE_ADDR']
self.META['REMOTE_PORT'] = self.scope['client'][1]
if self.scope.get('server'):
self.META['SERVER_NAME'] = self.scope['server'][0]
self.META['SERVER_PORT'] = str(self.scope['server'][1])
else:
self.META['SERVER_NAME'] = 'unknown'
self.META['SERVER_PORT'] = '0'
# Headers go into META.
for name, value in self.scope.get('headers', []):
name = name.decode('latin1')
if name == 'content-length':
corrected_name = 'CONTENT_LENGTH'
elif name == 'content-type':
corrected_name = 'CONTENT_TYPE'
else:
corrected_name = 'HTTP_%s' % name.upper().replace('-', '_')
# HTTP/2 say only ASCII chars are allowed in headers, but decode
# latin1 just in case.
value = value.decode('latin1')
if corrected_name in self.META:
value = self.META[corrected_name] + ',' + value
self.META[corrected_name] = value
# Pull out request encoding, if provided.
self._set_content_type_params(self.META)
# Directly assign the body file to be our stream.
self._stream = body_file
# Other bits.
self.resolver_match = None
@cached_property
def GET(self):
return QueryDict(self.META['QUERY_STRING'])
def _get_scheme(self):
return self.scope.get('scheme') or super()._get_scheme()
def _get_post(self):
if not hasattr(self, '_post'):
self._load_post_and_files()
return self._post
def _set_post(self, post):
self._post = post
def _get_files(self):
if not hasattr(self, '_files'):
self._load_post_and_files()
return self._files
POST = property(_get_post, _set_post)
FILES = property(_get_files)
@cached_property
def COOKIES(self):
return parse_cookie(self.META.get('HTTP_COOKIE', ''))
class ASGIHandler(base.BaseHandler):
"""Handler for ASGI requests."""
request_class = ASGIRequest
# Size to chunk response bodies into for multiple response messages.
chunk_size = 2 ** 16
def __init__(self):
super().__init__()
self.load_middleware(is_async=True)
async def __call__(self, scope, receive, send):
"""
Async entrypoint - parses the request and hands off to get_response.
"""
# Serve only HTTP connections.
# FIXME: Allow to override this.
if scope['type'] != 'http':
raise ValueError(
'Django can only handle ASGI/HTTP connections, not %s.'
% scope['type']
)
# Receive the HTTP request body as a stream object.
try:
body_file = await self.read_body(receive)
except RequestAborted:
return
# Request is complete and can be served.
set_script_prefix(self.get_script_prefix(scope))
await sync_to_async(signals.request_started.send, thread_sensitive=True)(sender=self.__class__, scope=scope)
# Get the request and check for basic issues.
request, error_response = self.create_request(scope, body_file)
if request is None:
await self.send_response(error_response, send)
return
# Get the response, using the async mode of BaseHandler.
response = await self.get_response_async(request)
response._handler_class = self.__class__
# Increase chunk size on file responses (ASGI servers handles low-level
# chunking).
if isinstance(response, FileResponse):
response.block_size = self.chunk_size
# Send the response.
await self.send_response(response, send)
async def read_body(self, receive):
"""Reads a HTTP body from an ASGI connection."""
# Use the tempfile that auto rolls-over to a disk file as it fills up.
body_file = tempfile.SpooledTemporaryFile(max_size=settings.FILE_UPLOAD_MAX_MEMORY_SIZE, mode='w+b')
while True:
message = await receive()
if message['type'] == 'http.disconnect':
# Early client disconnect.
raise RequestAborted()
# Add a body chunk from the message, if provided.
if 'body' in message:
body_file.write(message['body'])
# Quit out if that's the end.
if not message.get('more_body', False):
break
body_file.seek(0)
return body_file
def create_request(self, scope, body_file):
"""
Create the Request object and returns either (request, None) or
(None, response) if there is an error response.
"""
try:
return self.request_class(scope, body_file), None
except UnicodeDecodeError:
logger.warning(
'Bad Request (UnicodeDecodeError)',
exc_info=sys.exc_info(),
extra={'status_code': 400},
)
return None, HttpResponseBadRequest()
except RequestDataTooBig:
return None, HttpResponse('413 Payload too large', status=413)
def handle_uncaught_exception(self, request, resolver, exc_info):
"""Last-chance handler for exceptions."""
# There's no WSGI server to catch the exception further up
# if this fails, so translate it into a plain text response.
try:
return super().handle_uncaught_exception(request, resolver, exc_info)
except Exception:
return HttpResponseServerError(
traceback.format_exc() if settings.DEBUG else 'Internal Server Error',
content_type='text/plain',
)
async def send_response(self, response, send):
"""Encode and send a response out over ASGI."""
# Collect cookies into headers. Have to preserve header case as there
# are some non-RFC compliant clients that require e.g. Content-Type.
response_headers = []
for header, value in response.items():
if isinstance(header, str):
header = header.encode('ascii')
if isinstance(value, str):
value = value.encode('latin1')
response_headers.append((bytes(header), bytes(value)))
for c in response.cookies.values():
response_headers.append(
(b'Set-Cookie', c.output(header='').encode('ascii').strip())
)
# Initial response message.
await send({
'type': 'http.response.start',
'status': response.status_code,
'headers': response_headers,
})
# Streaming responses need to be pinned to their iterator.
if response.streaming:
# Access `__iter__` and not `streaming_content` directly in case
# it has been overridden in a subclass.
for part in response:
for chunk, _ in self.chunk_bytes(part):
await send({
'type': 'http.response.body',
'body': chunk,
# Ignore "more" as there may be more parts; instead,
# use an empty final closing message with False.
'more_body': True,
})
# Final closing message.
await send({'type': 'http.response.body'})
# Other responses just need chunking.
else:
# Yield chunks of response.
for chunk, last in self.chunk_bytes(response.content):
await send({
'type': 'http.response.body',
'body': chunk,
'more_body': not last,
})
await sync_to_async(response.close, thread_sensitive=True)()
@classmethod
def chunk_bytes(cls, data):
"""
Chunks some data up so it can be sent in reasonable size messages.
Yields (chunk, last_chunk) tuples.
"""
position = 0
if not data:
yield data, True
return
while position < len(data):
yield (
data[position:position + cls.chunk_size],
(position + cls.chunk_size) >= len(data),
)
position += cls.chunk_size
def get_script_prefix(self, scope):
"""
Return the script prefix to use from either the scope or a setting.
"""
if settings.FORCE_SCRIPT_NAME:
return settings.FORCE_SCRIPT_NAME
return scope.get('root_path', '') or ''
|
a887e2788c996a97e9211d469ae21a05e8ee23d6ebaeffcfa3749ecc077e8254 | from io import BytesIO
from django.conf import settings
from django.core import signals
from django.core.handlers import base
from django.http import HttpRequest, QueryDict, parse_cookie
from django.urls import set_script_prefix
from django.utils.encoding import repercent_broken_unicode
from django.utils.functional import cached_property
from django.utils.regex_helper import _lazy_re_compile
_slashes_re = _lazy_re_compile(br'/+')
class LimitedStream:
"""Wrap another stream to disallow reading it past a number of bytes."""
def __init__(self, stream, limit, buf_size=64 * 1024 * 1024):
self.stream = stream
self.remaining = limit
self.buffer = b''
self.buf_size = buf_size
def _read_limited(self, size=None):
if size is None or size > self.remaining:
size = self.remaining
if size == 0:
return b''
result = self.stream.read(size)
self.remaining -= len(result)
return result
def read(self, size=None):
if size is None:
result = self.buffer + self._read_limited()
self.buffer = b''
elif size < len(self.buffer):
result = self.buffer[:size]
self.buffer = self.buffer[size:]
else: # size >= len(self.buffer)
result = self.buffer + self._read_limited(size - len(self.buffer))
self.buffer = b''
return result
def readline(self, size=None):
while b'\n' not in self.buffer and \
(size is None or len(self.buffer) < size):
if size:
# since size is not None here, len(self.buffer) < size
chunk = self._read_limited(size - len(self.buffer))
else:
chunk = self._read_limited()
if not chunk:
break
self.buffer += chunk
sio = BytesIO(self.buffer)
if size:
line = sio.readline(size)
else:
line = sio.readline()
self.buffer = sio.read()
return line
class WSGIRequest(HttpRequest):
def __init__(self, environ):
script_name = get_script_name(environ)
# If PATH_INFO is empty (e.g. accessing the SCRIPT_NAME URL without a
# trailing slash), operate as if '/' was requested.
path_info = get_path_info(environ) or '/'
self.environ = environ
self.path_info = path_info
# be careful to only replace the first slash in the path because of
# http://test/something and http://test//something being different as
# stated in https://www.ietf.org/rfc/rfc2396.txt
self.path = '%s/%s' % (script_name.rstrip('/'),
path_info.replace('/', '', 1))
self.META = environ
self.META['PATH_INFO'] = path_info
self.META['SCRIPT_NAME'] = script_name
self.method = environ['REQUEST_METHOD'].upper()
# Set content_type, content_params, and encoding.
self._set_content_type_params(environ)
try:
content_length = int(environ.get('CONTENT_LENGTH'))
except (ValueError, TypeError):
content_length = 0
self._stream = LimitedStream(self.environ['wsgi.input'], content_length)
self._read_started = False
self.resolver_match = None
def _get_scheme(self):
return self.environ.get('wsgi.url_scheme')
@cached_property
def GET(self):
# The WSGI spec says 'QUERY_STRING' may be absent.
raw_query_string = get_bytes_from_wsgi(self.environ, 'QUERY_STRING', '')
return QueryDict(raw_query_string, encoding=self._encoding)
def _get_post(self):
if not hasattr(self, '_post'):
self._load_post_and_files()
return self._post
def _set_post(self, post):
self._post = post
@cached_property
def COOKIES(self):
raw_cookie = get_str_from_wsgi(self.environ, 'HTTP_COOKIE', '')
return parse_cookie(raw_cookie)
@property
def FILES(self):
if not hasattr(self, '_files'):
self._load_post_and_files()
return self._files
POST = property(_get_post, _set_post)
class WSGIHandler(base.BaseHandler):
request_class = WSGIRequest
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.load_middleware()
def __call__(self, environ, start_response):
set_script_prefix(get_script_name(environ))
signals.request_started.send(sender=self.__class__, environ=environ)
request = self.request_class(environ)
response = self.get_response(request)
response._handler_class = self.__class__
status = '%d %s' % (response.status_code, response.reason_phrase)
response_headers = [
*response.items(),
*(('Set-Cookie', c.output(header='')) for c in response.cookies.values()),
]
start_response(status, response_headers)
if getattr(response, 'file_to_stream', None) is not None and environ.get('wsgi.file_wrapper'):
# If `wsgi.file_wrapper` is used the WSGI server does not call
# .close on the response, but on the file wrapper. Patch it to use
# response.close instead which takes care of closing all files.
response.file_to_stream.close = response.close
response = environ['wsgi.file_wrapper'](response.file_to_stream, response.block_size)
return response
def get_path_info(environ):
"""Return the HTTP request's PATH_INFO as a string."""
path_info = get_bytes_from_wsgi(environ, 'PATH_INFO', '/')
return repercent_broken_unicode(path_info).decode()
def get_script_name(environ):
"""
Return the equivalent of the HTTP request's SCRIPT_NAME environment
variable. If Apache mod_rewrite is used, return what would have been
the script name prior to any rewriting (so it's the script name as seen
from the client's perspective), unless the FORCE_SCRIPT_NAME setting is
set (to anything).
"""
if settings.FORCE_SCRIPT_NAME is not None:
return settings.FORCE_SCRIPT_NAME
# If Apache's mod_rewrite had a whack at the URL, Apache set either
# SCRIPT_URL or REDIRECT_URL to the full resource URL before applying any
# rewrites. Unfortunately not every Web server (lighttpd!) passes this
# information through all the time, so FORCE_SCRIPT_NAME, above, is still
# needed.
script_url = get_bytes_from_wsgi(environ, 'SCRIPT_URL', '') or get_bytes_from_wsgi(environ, 'REDIRECT_URL', '')
if script_url:
if b'//' in script_url:
# mod_wsgi squashes multiple successive slashes in PATH_INFO,
# do the same with script_url before manipulating paths (#17133).
script_url = _slashes_re.sub(b'/', script_url)
path_info = get_bytes_from_wsgi(environ, 'PATH_INFO', '')
script_name = script_url[:-len(path_info)] if path_info else script_url
else:
script_name = get_bytes_from_wsgi(environ, 'SCRIPT_NAME', '')
return script_name.decode()
def get_bytes_from_wsgi(environ, key, default):
"""
Get a value from the WSGI environ dictionary as bytes.
key and default should be strings.
"""
value = environ.get(key, default)
# Non-ASCII values in the WSGI environ are arbitrarily decoded with
# ISO-8859-1. This is wrong for Django websites where UTF-8 is the default.
# Re-encode to recover the original bytestring.
return value.encode('iso-8859-1')
def get_str_from_wsgi(environ, key, default):
"""
Get a value from the WSGI environ dictionary as str.
key and default should be str objects.
"""
value = get_bytes_from_wsgi(environ, key, default)
return value.decode(errors='replace')
|
af94ae12b20349a41e2cc2674db796ce9b099e27d68272ebd3e2211b9d657432 | import asyncio
import logging
import sys
from functools import wraps
from asgiref.sync import sync_to_async
from django.conf import settings
from django.core import signals
from django.core.exceptions import (
PermissionDenied, RequestDataTooBig, SuspiciousOperation,
TooManyFieldsSent,
)
from django.http import Http404
from django.http.multipartparser import MultiPartParserError
from django.urls import get_resolver, get_urlconf
from django.utils.log import log_response
from django.views import debug
def convert_exception_to_response(get_response):
"""
Wrap the given get_response callable in exception-to-response conversion.
All exceptions will be converted. All known 4xx exceptions (Http404,
PermissionDenied, MultiPartParserError, SuspiciousOperation) will be
converted to the appropriate response, and all other exceptions will be
converted to 500 responses.
This decorator is automatically applied to all middleware to ensure that
no middleware leaks an exception and that the next middleware in the stack
can rely on getting a response instead of an exception.
"""
if asyncio.iscoroutinefunction(get_response):
@wraps(get_response)
async def inner(request):
try:
response = await get_response(request)
except Exception as exc:
response = await sync_to_async(response_for_exception)(request, exc)
return response
return inner
else:
@wraps(get_response)
def inner(request):
try:
response = get_response(request)
except Exception as exc:
response = response_for_exception(request, exc)
return response
return inner
def response_for_exception(request, exc):
if isinstance(exc, Http404):
if settings.DEBUG:
response = debug.technical_404_response(request, exc)
else:
response = get_exception_response(request, get_resolver(get_urlconf()), 404, exc)
elif isinstance(exc, PermissionDenied):
response = get_exception_response(request, get_resolver(get_urlconf()), 403, exc)
log_response(
'Forbidden (Permission denied): %s', request.path,
response=response,
request=request,
exc_info=sys.exc_info(),
)
elif isinstance(exc, MultiPartParserError):
response = get_exception_response(request, get_resolver(get_urlconf()), 400, exc)
log_response(
'Bad request (Unable to parse request body): %s', request.path,
response=response,
request=request,
exc_info=sys.exc_info(),
)
elif isinstance(exc, SuspiciousOperation):
if isinstance(exc, (RequestDataTooBig, TooManyFieldsSent)):
# POST data can't be accessed again, otherwise the original
# exception would be raised.
request._mark_post_parse_error()
# The request logger receives events for any problematic request
# The security logger receives events for all SuspiciousOperations
security_logger = logging.getLogger('django.security.%s' % exc.__class__.__name__)
security_logger.error(
str(exc),
extra={'status_code': 400, 'request': request},
)
if settings.DEBUG:
response = debug.technical_500_response(request, *sys.exc_info(), status_code=400)
else:
response = get_exception_response(request, get_resolver(get_urlconf()), 400, exc)
elif isinstance(exc, SystemExit):
# Allow sys.exit() to actually exit. See tickets #1023 and #4701
raise
else:
signals.got_request_exception.send(sender=None, request=request)
response = handle_uncaught_exception(request, get_resolver(get_urlconf()), sys.exc_info())
log_response(
'%s: %s', response.reason_phrase, request.path,
response=response,
request=request,
exc_info=sys.exc_info(),
)
# Force a TemplateResponse to be rendered.
if not getattr(response, 'is_rendered', True) and callable(getattr(response, 'render', None)):
response = response.render()
return response
def get_exception_response(request, resolver, status_code, exception):
try:
callback, param_dict = resolver.resolve_error_handler(status_code)
response = callback(request, **{**param_dict, 'exception': exception})
except Exception:
signals.got_request_exception.send(sender=None, request=request)
response = handle_uncaught_exception(request, resolver, sys.exc_info())
return response
def handle_uncaught_exception(request, resolver, exc_info):
"""
Processing for any otherwise uncaught exceptions (those that will
generate HTTP 500 responses).
"""
if settings.DEBUG_PROPAGATE_EXCEPTIONS:
raise
if settings.DEBUG:
return debug.technical_500_response(request, *exc_info)
# Return an HttpResponse that displays a friendly error message.
callback, param_dict = resolver.resolve_error_handler(500)
return callback(request, **param_dict)
|
97f87282c5d645448c4a11273424626a9bf34473512d6b965533d0e45d469a97 | import asyncio
import logging
import types
from asgiref.sync import async_to_sync, sync_to_async
from django.conf import settings
from django.core.exceptions import ImproperlyConfigured, MiddlewareNotUsed
from django.core.signals import request_finished
from django.db import connections, transaction
from django.urls import get_resolver, set_urlconf
from django.utils.log import log_response
from django.utils.module_loading import import_string
from .exception import convert_exception_to_response
logger = logging.getLogger('django.request')
class BaseHandler:
_view_middleware = None
_template_response_middleware = None
_exception_middleware = None
_middleware_chain = None
def load_middleware(self, is_async=False):
"""
Populate middleware lists from settings.MIDDLEWARE.
Must be called after the environment is fixed (see __call__ in subclasses).
"""
self._view_middleware = []
self._template_response_middleware = []
self._exception_middleware = []
get_response = self._get_response_async if is_async else self._get_response
handler = convert_exception_to_response(get_response)
handler_is_async = is_async
for middleware_path in reversed(settings.MIDDLEWARE):
middleware = import_string(middleware_path)
middleware_can_sync = getattr(middleware, 'sync_capable', True)
middleware_can_async = getattr(middleware, 'async_capable', False)
if not middleware_can_sync and not middleware_can_async:
raise RuntimeError(
'Middleware %s must have at least one of '
'sync_capable/async_capable set to True.' % middleware_path
)
elif not handler_is_async and middleware_can_sync:
middleware_is_async = False
else:
middleware_is_async = middleware_can_async
try:
# Adapt handler, if needed.
handler = self.adapt_method_mode(
middleware_is_async, handler, handler_is_async,
debug=settings.DEBUG, name='middleware %s' % middleware_path,
)
mw_instance = middleware(handler)
except MiddlewareNotUsed as exc:
if settings.DEBUG:
if str(exc):
logger.debug('MiddlewareNotUsed(%r): %s', middleware_path, exc)
else:
logger.debug('MiddlewareNotUsed: %r', middleware_path)
continue
if mw_instance is None:
raise ImproperlyConfigured(
'Middleware factory %s returned None.' % middleware_path
)
if hasattr(mw_instance, 'process_view'):
self._view_middleware.insert(
0,
self.adapt_method_mode(is_async, mw_instance.process_view),
)
if hasattr(mw_instance, 'process_template_response'):
self._template_response_middleware.append(
self.adapt_method_mode(is_async, mw_instance.process_template_response),
)
if hasattr(mw_instance, 'process_exception'):
# The exception-handling stack is still always synchronous for
# now, so adapt that way.
self._exception_middleware.append(
self.adapt_method_mode(False, mw_instance.process_exception),
)
handler = convert_exception_to_response(mw_instance)
handler_is_async = middleware_is_async
# Adapt the top of the stack, if needed.
handler = self.adapt_method_mode(is_async, handler, handler_is_async)
# We only assign to this when initialization is complete as it is used
# as a flag for initialization being complete.
self._middleware_chain = handler
def adapt_method_mode(
self, is_async, method, method_is_async=None, debug=False, name=None,
):
"""
Adapt a method to be in the correct "mode":
- If is_async is False:
- Synchronous methods are left alone
- Asynchronous methods are wrapped with async_to_sync
- If is_async is True:
- Synchronous methods are wrapped with sync_to_async()
- Asynchronous methods are left alone
"""
if method_is_async is None:
method_is_async = asyncio.iscoroutinefunction(method)
if debug and not name:
name = name or 'method %s()' % method.__qualname__
if is_async:
if not method_is_async:
if debug:
logger.debug('Synchronous %s adapted.', name)
return sync_to_async(method, thread_sensitive=True)
elif method_is_async:
if debug:
logger.debug('Asynchronous %s adapted.' % name)
return async_to_sync(method)
return method
def get_response(self, request):
"""Return an HttpResponse object for the given HttpRequest."""
# Setup default url resolver for this thread
set_urlconf(settings.ROOT_URLCONF)
response = self._middleware_chain(request)
response._resource_closers.append(request.close)
if response.status_code >= 400:
log_response(
'%s: %s', response.reason_phrase, request.path,
response=response,
request=request,
)
return response
async def get_response_async(self, request):
"""
Asynchronous version of get_response.
Funneling everything, including WSGI, into a single async
get_response() is too slow. Avoid the context switch by using
a separate async response path.
"""
# Setup default url resolver for this thread.
set_urlconf(settings.ROOT_URLCONF)
response = await self._middleware_chain(request)
response._resource_closers.append(request.close)
if response.status_code >= 400:
await sync_to_async(log_response)(
'%s: %s', response.reason_phrase, request.path,
response=response,
request=request,
)
return response
def _get_response(self, request):
"""
Resolve and call the view, then apply view, exception, and
template_response middleware. This method is everything that happens
inside the request/response middleware.
"""
response = None
callback, callback_args, callback_kwargs = self.resolve_request(request)
# Apply view middleware
for middleware_method in self._view_middleware:
response = middleware_method(request, callback, callback_args, callback_kwargs)
if response:
break
if response is None:
wrapped_callback = self.make_view_atomic(callback)
# If it is an asynchronous view, run it in a subthread.
if asyncio.iscoroutinefunction(wrapped_callback):
wrapped_callback = async_to_sync(wrapped_callback)
try:
response = wrapped_callback(request, *callback_args, **callback_kwargs)
except Exception as e:
response = self.process_exception_by_middleware(e, request)
# Complain if the view returned None (a common error).
self.check_response(response, callback)
# If the response supports deferred rendering, apply template
# response middleware and then render the response
if hasattr(response, 'render') and callable(response.render):
for middleware_method in self._template_response_middleware:
response = middleware_method(request, response)
# Complain if the template response middleware returned None (a common error).
self.check_response(
response,
middleware_method,
name='%s.process_template_response' % (
middleware_method.__self__.__class__.__name__,
)
)
try:
response = response.render()
except Exception as e:
response = self.process_exception_by_middleware(e, request)
return response
async def _get_response_async(self, request):
"""
Resolve and call the view, then apply view, exception, and
template_response middleware. This method is everything that happens
inside the request/response middleware.
"""
response = None
callback, callback_args, callback_kwargs = self.resolve_request(request)
# Apply view middleware.
for middleware_method in self._view_middleware:
response = await middleware_method(request, callback, callback_args, callback_kwargs)
if response:
break
if response is None:
wrapped_callback = self.make_view_atomic(callback)
# If it is a synchronous view, run it in a subthread
if not asyncio.iscoroutinefunction(wrapped_callback):
wrapped_callback = sync_to_async(wrapped_callback, thread_sensitive=True)
try:
response = await wrapped_callback(request, *callback_args, **callback_kwargs)
except Exception as e:
response = await sync_to_async(
self.process_exception_by_middleware,
thread_sensitive=True,
)(e, request)
# Complain if the view returned None or an uncalled coroutine.
self.check_response(response, callback)
# If the response supports deferred rendering, apply template
# response middleware and then render the response
if hasattr(response, 'render') and callable(response.render):
for middleware_method in self._template_response_middleware:
response = await middleware_method(request, response)
# Complain if the template response middleware returned None or
# an uncalled coroutine.
self.check_response(
response,
middleware_method,
name='%s.process_template_response' % (
middleware_method.__self__.__class__.__name__,
)
)
try:
if asyncio.iscoroutinefunction(response.render):
response = await response.render()
else:
response = await sync_to_async(response.render, thread_sensitive=True)()
except Exception as e:
response = await sync_to_async(
self.process_exception_by_middleware,
thread_sensitive=True,
)(e, request)
# Make sure the response is not a coroutine
if asyncio.iscoroutine(response):
raise RuntimeError('Response is still a coroutine.')
return response
def resolve_request(self, request):
"""
Retrieve/set the urlconf for the request. Return the view resolved,
with its args and kwargs.
"""
# Work out the resolver.
if hasattr(request, 'urlconf'):
urlconf = request.urlconf
set_urlconf(urlconf)
resolver = get_resolver(urlconf)
else:
resolver = get_resolver()
# Resolve the view, and assign the match object back to the request.
resolver_match = resolver.resolve(request.path_info)
request.resolver_match = resolver_match
return resolver_match
def check_response(self, response, callback, name=None):
"""
Raise an error if the view returned None or an uncalled coroutine.
"""
if not(response is None or asyncio.iscoroutine(response)):
return
if not name:
if isinstance(callback, types.FunctionType): # FBV
name = 'The view %s.%s' % (callback.__module__, callback.__name__)
else: # CBV
name = 'The view %s.%s.__call__' % (
callback.__module__,
callback.__class__.__name__,
)
if response is None:
raise ValueError(
"%s didn't return an HttpResponse object. It returned None "
"instead." % name
)
elif asyncio.iscoroutine(response):
raise ValueError(
"%s didn't return an HttpResponse object. It returned an "
"unawaited coroutine instead. You may need to add an 'await' "
"into your view." % name
)
# Other utility methods.
def make_view_atomic(self, view):
non_atomic_requests = getattr(view, '_non_atomic_requests', set())
for db in connections.all():
if db.settings_dict['ATOMIC_REQUESTS'] and db.alias not in non_atomic_requests:
if asyncio.iscoroutinefunction(view):
raise RuntimeError(
'You cannot use ATOMIC_REQUESTS with async views.'
)
view = transaction.atomic(using=db.alias)(view)
return view
def process_exception_by_middleware(self, exception, request):
"""
Pass the exception to the exception middleware. If no middleware
return a response for this exception, raise it.
"""
for middleware_method in self._exception_middleware:
response = middleware_method(request, exception)
if response:
return response
raise
def reset_urlconf(sender, **kwargs):
"""Reset the URLconf after each request is finished."""
set_urlconf(None)
request_finished.connect(reset_urlconf)
|
2d2e7da09d02d6f1ac36d55c0281322e06250c80075671cc2dfaa23036ae41f1 | """
Tools for sending email.
"""
from django.conf import settings
# Imported for backwards compatibility and for the sake
# of a cleaner namespace. These symbols used to be in
# django/core/mail.py before the introduction of email
# backends and the subsequent reorganization (See #10355)
from django.core.mail.message import (
DEFAULT_ATTACHMENT_MIME_TYPE, BadHeaderError, EmailMessage,
EmailMultiAlternatives, SafeMIMEMultipart, SafeMIMEText,
forbid_multi_line_headers, make_msgid,
)
from django.core.mail.utils import DNS_NAME, CachedDnsName
from django.utils.module_loading import import_string
__all__ = [
'CachedDnsName', 'DNS_NAME', 'EmailMessage', 'EmailMultiAlternatives',
'SafeMIMEText', 'SafeMIMEMultipart', 'DEFAULT_ATTACHMENT_MIME_TYPE',
'make_msgid', 'BadHeaderError', 'forbid_multi_line_headers',
'get_connection', 'send_mail', 'send_mass_mail', 'mail_admins',
'mail_managers',
]
def get_connection(backend=None, fail_silently=False, **kwds):
"""Load an email backend and return an instance of it.
If backend is None (default), use settings.EMAIL_BACKEND.
Both fail_silently and other keyword arguments are used in the
constructor of the backend.
"""
klass = import_string(backend or settings.EMAIL_BACKEND)
return klass(fail_silently=fail_silently, **kwds)
def send_mail(subject, message, from_email, recipient_list,
fail_silently=False, auth_user=None, auth_password=None,
connection=None, html_message=None):
"""
Easy wrapper for sending a single message to a recipient list. All members
of the recipient list will see the other recipients in the 'To' field.
If from_email is None, use the DEFAULT_FROM_EMAIL setting.
If auth_user is None, use the EMAIL_HOST_USER setting.
If auth_password is None, use the EMAIL_HOST_PASSWORD setting.
Note: The API for this method is frozen. New code wanting to extend the
functionality should use the EmailMessage class directly.
"""
connection = connection or get_connection(
username=auth_user,
password=auth_password,
fail_silently=fail_silently,
)
mail = EmailMultiAlternatives(subject, message, from_email, recipient_list, connection=connection)
if html_message:
mail.attach_alternative(html_message, 'text/html')
return mail.send()
def send_mass_mail(datatuple, fail_silently=False, auth_user=None,
auth_password=None, connection=None):
"""
Given a datatuple of (subject, message, from_email, recipient_list), send
each message to each recipient list. Return the number of emails sent.
If from_email is None, use the DEFAULT_FROM_EMAIL setting.
If auth_user and auth_password are set, use them to log in.
If auth_user is None, use the EMAIL_HOST_USER setting.
If auth_password is None, use the EMAIL_HOST_PASSWORD setting.
Note: The API for this method is frozen. New code wanting to extend the
functionality should use the EmailMessage class directly.
"""
connection = connection or get_connection(
username=auth_user,
password=auth_password,
fail_silently=fail_silently,
)
messages = [
EmailMessage(subject, message, sender, recipient, connection=connection)
for subject, message, sender, recipient in datatuple
]
return connection.send_messages(messages)
def mail_admins(subject, message, fail_silently=False, connection=None,
html_message=None):
"""Send a message to the admins, as defined by the ADMINS setting."""
if not settings.ADMINS:
return
if not all(isinstance(a, (list, tuple)) and len(a) == 2 for a in settings.ADMINS):
raise ValueError('The ADMINS setting must be a list of 2-tuples.')
mail = EmailMultiAlternatives(
'%s%s' % (settings.EMAIL_SUBJECT_PREFIX, subject), message,
settings.SERVER_EMAIL, [a[1] for a in settings.ADMINS],
connection=connection,
)
if html_message:
mail.attach_alternative(html_message, 'text/html')
mail.send(fail_silently=fail_silently)
def mail_managers(subject, message, fail_silently=False, connection=None,
html_message=None):
"""Send a message to the managers, as defined by the MANAGERS setting."""
if not settings.MANAGERS:
return
if not all(isinstance(a, (list, tuple)) and len(a) == 2 for a in settings.MANAGERS):
raise ValueError('The MANAGERS setting must be a list of 2-tuples.')
mail = EmailMultiAlternatives(
'%s%s' % (settings.EMAIL_SUBJECT_PREFIX, subject), message,
settings.SERVER_EMAIL, [a[1] for a in settings.MANAGERS],
connection=connection,
)
if html_message:
mail.attach_alternative(html_message, 'text/html')
mail.send(fail_silently=fail_silently)
|
035014899ca50471ab2f015a54fae3828583e770ae59d5815f1c5743c4b6d406 | import sys
import time
from importlib import import_module
from django.apps import apps
from django.core.management.base import (
BaseCommand, CommandError, no_translations,
)
from django.core.management.sql import (
emit_post_migrate_signal, emit_pre_migrate_signal,
)
from django.db import DEFAULT_DB_ALIAS, connections, router
from django.db.migrations.autodetector import MigrationAutodetector
from django.db.migrations.executor import MigrationExecutor
from django.db.migrations.loader import AmbiguityError
from django.db.migrations.state import ModelState, ProjectState
from django.utils.module_loading import module_has_submodule
from django.utils.text import Truncator
class Command(BaseCommand):
help = "Updates database schema. Manages both apps with migrations and those without."
requires_system_checks = False
def add_arguments(self, parser):
parser.add_argument(
'--skip-checks', action='store_true',
help='Skip system checks.',
)
parser.add_argument(
'app_label', nargs='?',
help='App label of an application to synchronize the state.',
)
parser.add_argument(
'migration_name', nargs='?',
help='Database state will be brought to the state after that '
'migration. Use the name "zero" to unapply all migrations.',
)
parser.add_argument(
'--noinput', '--no-input', action='store_false', dest='interactive',
help='Tells Django to NOT prompt the user for input of any kind.',
)
parser.add_argument(
'--database',
default=DEFAULT_DB_ALIAS,
help='Nominates a database to synchronize. Defaults to the "default" database.',
)
parser.add_argument(
'--fake', action='store_true',
help='Mark migrations as run without actually running them.',
)
parser.add_argument(
'--fake-initial', action='store_true',
help='Detect if tables already exist and fake-apply initial migrations if so. Make sure '
'that the current database schema matches your initial migration before using this '
'flag. Django will only check for an existing table name.',
)
parser.add_argument(
'--plan', action='store_true',
help='Shows a list of the migration actions that will be performed.',
)
parser.add_argument(
'--run-syncdb', action='store_true',
help='Creates tables for apps without migrations.',
)
parser.add_argument(
'--check', action='store_true', dest='check_unapplied',
help='Exits with a non-zero status if unapplied migrations exist.',
)
@no_translations
def handle(self, *args, **options):
database = options['database']
if not options['skip_checks']:
self.check(databases=[database])
self.verbosity = options['verbosity']
self.interactive = options['interactive']
# Import the 'management' module within each installed app, to register
# dispatcher events.
for app_config in apps.get_app_configs():
if module_has_submodule(app_config.module, "management"):
import_module('.management', app_config.name)
# Get the database we're operating from
connection = connections[database]
# Hook for backends needing any database preparation
connection.prepare_database()
# Work out which apps have migrations and which do not
executor = MigrationExecutor(connection, self.migration_progress_callback)
# Raise an error if any migrations are applied before their dependencies.
executor.loader.check_consistent_history(connection)
# Before anything else, see if there's conflicting apps and drop out
# hard if there are any
conflicts = executor.loader.detect_conflicts()
if conflicts:
name_str = "; ".join(
"%s in %s" % (", ".join(names), app)
for app, names in conflicts.items()
)
raise CommandError(
"Conflicting migrations detected; multiple leaf nodes in the "
"migration graph: (%s).\nTo fix them run "
"'python manage.py makemigrations --merge'" % name_str
)
# If they supplied command line arguments, work out what they mean.
run_syncdb = options['run_syncdb']
target_app_labels_only = True
if options['app_label']:
# Validate app_label.
app_label = options['app_label']
try:
apps.get_app_config(app_label)
except LookupError as err:
raise CommandError(str(err))
if run_syncdb:
if app_label in executor.loader.migrated_apps:
raise CommandError("Can't use run_syncdb with app '%s' as it has migrations." % app_label)
elif app_label not in executor.loader.migrated_apps:
raise CommandError("App '%s' does not have migrations." % app_label)
if options['app_label'] and options['migration_name']:
migration_name = options['migration_name']
if migration_name == "zero":
targets = [(app_label, None)]
else:
try:
migration = executor.loader.get_migration_by_prefix(app_label, migration_name)
except AmbiguityError:
raise CommandError(
"More than one migration matches '%s' in app '%s'. "
"Please be more specific." %
(migration_name, app_label)
)
except KeyError:
raise CommandError("Cannot find a migration matching '%s' from app '%s'." % (
migration_name, app_label))
targets = [(app_label, migration.name)]
target_app_labels_only = False
elif options['app_label']:
targets = [key for key in executor.loader.graph.leaf_nodes() if key[0] == app_label]
else:
targets = executor.loader.graph.leaf_nodes()
plan = executor.migration_plan(targets)
exit_dry = plan and options['check_unapplied']
if options['plan']:
self.stdout.write('Planned operations:', self.style.MIGRATE_LABEL)
if not plan:
self.stdout.write(' No planned migration operations.')
for migration, backwards in plan:
self.stdout.write(str(migration), self.style.MIGRATE_HEADING)
for operation in migration.operations:
message, is_error = self.describe_operation(operation, backwards)
style = self.style.WARNING if is_error else None
self.stdout.write(' ' + message, style)
if exit_dry:
sys.exit(1)
return
if exit_dry:
sys.exit(1)
# At this point, ignore run_syncdb if there aren't any apps to sync.
run_syncdb = options['run_syncdb'] and executor.loader.unmigrated_apps
# Print some useful info
if self.verbosity >= 1:
self.stdout.write(self.style.MIGRATE_HEADING("Operations to perform:"))
if run_syncdb:
if options['app_label']:
self.stdout.write(
self.style.MIGRATE_LABEL(" Synchronize unmigrated app: %s" % app_label)
)
else:
self.stdout.write(
self.style.MIGRATE_LABEL(" Synchronize unmigrated apps: ") +
(", ".join(sorted(executor.loader.unmigrated_apps)))
)
if target_app_labels_only:
self.stdout.write(
self.style.MIGRATE_LABEL(" Apply all migrations: ") +
(", ".join(sorted({a for a, n in targets})) or "(none)")
)
else:
if targets[0][1] is None:
self.stdout.write(
self.style.MIGRATE_LABEL(' Unapply all migrations: ') +
str(targets[0][0])
)
else:
self.stdout.write(self.style.MIGRATE_LABEL(
" Target specific migration: ") + "%s, from %s"
% (targets[0][1], targets[0][0])
)
pre_migrate_state = executor._create_project_state(with_applied_migrations=True)
pre_migrate_apps = pre_migrate_state.apps
emit_pre_migrate_signal(
self.verbosity, self.interactive, connection.alias, apps=pre_migrate_apps, plan=plan,
)
# Run the syncdb phase.
if run_syncdb:
if self.verbosity >= 1:
self.stdout.write(self.style.MIGRATE_HEADING("Synchronizing apps without migrations:"))
if options['app_label']:
self.sync_apps(connection, [app_label])
else:
self.sync_apps(connection, executor.loader.unmigrated_apps)
# Migrate!
if self.verbosity >= 1:
self.stdout.write(self.style.MIGRATE_HEADING("Running migrations:"))
if not plan:
if self.verbosity >= 1:
self.stdout.write(" No migrations to apply.")
# If there's changes that aren't in migrations yet, tell them how to fix it.
autodetector = MigrationAutodetector(
executor.loader.project_state(),
ProjectState.from_apps(apps),
)
changes = autodetector.changes(graph=executor.loader.graph)
if changes:
self.stdout.write(self.style.NOTICE(
" Your models have changes that are not yet reflected "
"in a migration, and so won't be applied."
))
self.stdout.write(self.style.NOTICE(
" Run 'manage.py makemigrations' to make new "
"migrations, and then re-run 'manage.py migrate' to "
"apply them."
))
fake = False
fake_initial = False
else:
fake = options['fake']
fake_initial = options['fake_initial']
post_migrate_state = executor.migrate(
targets, plan=plan, state=pre_migrate_state.clone(), fake=fake,
fake_initial=fake_initial,
)
# post_migrate signals have access to all models. Ensure that all models
# are reloaded in case any are delayed.
post_migrate_state.clear_delayed_apps_cache()
post_migrate_apps = post_migrate_state.apps
# Re-render models of real apps to include relationships now that
# we've got a final state. This wouldn't be necessary if real apps
# models were rendered with relationships in the first place.
with post_migrate_apps.bulk_update():
model_keys = []
for model_state in post_migrate_apps.real_models:
model_key = model_state.app_label, model_state.name_lower
model_keys.append(model_key)
post_migrate_apps.unregister_model(*model_key)
post_migrate_apps.render_multiple([
ModelState.from_model(apps.get_model(*model)) for model in model_keys
])
# Send the post_migrate signal, so individual apps can do whatever they need
# to do at this point.
emit_post_migrate_signal(
self.verbosity, self.interactive, connection.alias, apps=post_migrate_apps, plan=plan,
)
def migration_progress_callback(self, action, migration=None, fake=False):
if self.verbosity >= 1:
compute_time = self.verbosity > 1
if action == "apply_start":
if compute_time:
self.start = time.monotonic()
self.stdout.write(" Applying %s..." % migration, ending="")
self.stdout.flush()
elif action == "apply_success":
elapsed = " (%.3fs)" % (time.monotonic() - self.start) if compute_time else ""
if fake:
self.stdout.write(self.style.SUCCESS(" FAKED" + elapsed))
else:
self.stdout.write(self.style.SUCCESS(" OK" + elapsed))
elif action == "unapply_start":
if compute_time:
self.start = time.monotonic()
self.stdout.write(" Unapplying %s..." % migration, ending="")
self.stdout.flush()
elif action == "unapply_success":
elapsed = " (%.3fs)" % (time.monotonic() - self.start) if compute_time else ""
if fake:
self.stdout.write(self.style.SUCCESS(" FAKED" + elapsed))
else:
self.stdout.write(self.style.SUCCESS(" OK" + elapsed))
elif action == "render_start":
if compute_time:
self.start = time.monotonic()
self.stdout.write(" Rendering model states...", ending="")
self.stdout.flush()
elif action == "render_success":
elapsed = " (%.3fs)" % (time.monotonic() - self.start) if compute_time else ""
self.stdout.write(self.style.SUCCESS(" DONE" + elapsed))
def sync_apps(self, connection, app_labels):
"""Run the old syncdb-style operation on a list of app_labels."""
with connection.cursor() as cursor:
tables = connection.introspection.table_names(cursor)
# Build the manifest of apps and models that are to be synchronized.
all_models = [
(
app_config.label,
router.get_migratable_models(app_config, connection.alias, include_auto_created=False),
)
for app_config in apps.get_app_configs()
if app_config.models_module is not None and app_config.label in app_labels
]
def model_installed(model):
opts = model._meta
converter = connection.introspection.identifier_converter
return not (
(converter(opts.db_table) in tables) or
(opts.auto_created and converter(opts.auto_created._meta.db_table) in tables)
)
manifest = {
app_name: list(filter(model_installed, model_list))
for app_name, model_list in all_models
}
# Create the tables for each model
if self.verbosity >= 1:
self.stdout.write(' Creating tables...')
with connection.schema_editor() as editor:
for app_name, model_list in manifest.items():
for model in model_list:
# Never install unmanaged models, etc.
if not model._meta.can_migrate(connection):
continue
if self.verbosity >= 3:
self.stdout.write(
' Processing %s.%s model' % (app_name, model._meta.object_name)
)
if self.verbosity >= 1:
self.stdout.write(' Creating table %s' % model._meta.db_table)
editor.create_model(model)
# Deferred SQL is executed when exiting the editor's context.
if self.verbosity >= 1:
self.stdout.write(' Running deferred SQL...')
@staticmethod
def describe_operation(operation, backwards):
"""Return a string that describes a migration operation for --plan."""
prefix = ''
is_error = False
if hasattr(operation, 'code'):
code = operation.reverse_code if backwards else operation.code
action = (code.__doc__ or '') if code else None
elif hasattr(operation, 'sql'):
action = operation.reverse_sql if backwards else operation.sql
else:
action = ''
if backwards:
prefix = 'Undo '
if action is not None:
action = str(action).replace('\n', '')
elif backwards:
action = 'IRREVERSIBLE'
is_error = True
if action:
action = ' -> ' + action
truncated = Truncator(action)
return prefix + operation.describe() + truncated.chars(40), is_error
|
430f8f2d7c9b06e5d23a77353cbbb622dd620d2bf1320e2d7dba596489fe9427 | from django.apps import apps
from django.core import checks
from django.core.checks.registry import registry
from django.core.management.base import BaseCommand, CommandError
class Command(BaseCommand):
help = "Checks the entire Django project for potential problems."
requires_system_checks = False
def add_arguments(self, parser):
parser.add_argument('args', metavar='app_label', nargs='*')
parser.add_argument(
'--tag', '-t', action='append', dest='tags',
help='Run only checks labeled with given tag.',
)
parser.add_argument(
'--list-tags', action='store_true',
help='List available tags.',
)
parser.add_argument(
'--deploy', action='store_true',
help='Check deployment settings.',
)
parser.add_argument(
'--fail-level',
default='ERROR',
choices=['CRITICAL', 'ERROR', 'WARNING', 'INFO', 'DEBUG'],
help=(
'Message level that will cause the command to exit with a '
'non-zero status. Default is ERROR.'
),
)
parser.add_argument(
'--database', action='append', dest='databases',
help='Run database related checks against these aliases.',
)
def handle(self, *app_labels, **options):
include_deployment_checks = options['deploy']
if options['list_tags']:
self.stdout.write('\n'.join(sorted(registry.tags_available(include_deployment_checks))))
return
if app_labels:
app_configs = [apps.get_app_config(app_label) for app_label in app_labels]
else:
app_configs = None
tags = options['tags']
if tags:
try:
invalid_tag = next(
tag for tag in tags if not checks.tag_exists(tag, include_deployment_checks)
)
except StopIteration:
# no invalid tags
pass
else:
raise CommandError('There is no system check with the "%s" tag.' % invalid_tag)
self.check(
app_configs=app_configs,
tags=tags,
display_num_errors=True,
include_deployment_checks=include_deployment_checks,
fail_level=getattr(checks, options['fail_level']),
databases=options['databases'],
)
|
ddd7dc0aa1a7a592967f1f3f30c02ac78eeca0c46a8e1c971df805a5bc9b5e17 | from importlib import import_module
from django.apps import apps
from django.core.management.base import BaseCommand, CommandError
from django.core.management.color import no_style
from django.core.management.sql import emit_post_migrate_signal, sql_flush
from django.db import DEFAULT_DB_ALIAS, connections
class Command(BaseCommand):
help = (
'Removes ALL DATA from the database, including data added during '
'migrations. Does not achieve a "fresh install" state.'
)
stealth_options = ('reset_sequences', 'allow_cascade', 'inhibit_post_migrate')
def add_arguments(self, parser):
parser.add_argument(
'--noinput', '--no-input', action='store_false', dest='interactive',
help='Tells Django to NOT prompt the user for input of any kind.',
)
parser.add_argument(
'--database', default=DEFAULT_DB_ALIAS,
help='Nominates a database to flush. Defaults to the "default" database.',
)
def handle(self, **options):
database = options['database']
connection = connections[database]
verbosity = options['verbosity']
interactive = options['interactive']
# The following are stealth options used by Django's internals.
reset_sequences = options.get('reset_sequences', True)
allow_cascade = options.get('allow_cascade', False)
inhibit_post_migrate = options.get('inhibit_post_migrate', False)
self.style = no_style()
# Import the 'management' module within each installed app, to register
# dispatcher events.
for app_config in apps.get_app_configs():
try:
import_module('.management', app_config.name)
except ImportError:
pass
sql_list = sql_flush(self.style, connection, only_django=True,
reset_sequences=reset_sequences,
allow_cascade=allow_cascade)
if interactive:
confirm = input("""You have requested a flush of the database.
This will IRREVERSIBLY DESTROY all data currently in the "%s" database,
and return each table to an empty state.
Are you sure you want to do this?
Type 'yes' to continue, or 'no' to cancel: """ % connection.settings_dict['NAME'])
else:
confirm = 'yes'
if confirm == 'yes':
try:
connection.ops.execute_sql_flush(sql_list)
except Exception as exc:
raise CommandError(
"Database %s couldn't be flushed. Possible reasons:\n"
" * The database isn't running or isn't configured correctly.\n"
" * At least one of the expected database tables doesn't exist.\n"
" * The SQL was invalid.\n"
"Hint: Look at the output of 'django-admin sqlflush'. "
"That's the SQL this command wasn't able to run." % (
connection.settings_dict['NAME'],
)
) from exc
# Empty sql_list may signify an empty database and post_migrate would then crash
if sql_list and not inhibit_post_migrate:
# Emit the post migrate signal. This allows individual applications to
# respond as if the database had been migrated from scratch.
emit_post_migrate_signal(verbosity, interactive, database)
else:
self.stdout.write('Flush cancelled.')
|
5dd49d32e0e1472b29c135f766da30e4671596539a96aefa5e7089f3e6dd6a26 | import warnings
from django.apps import apps
from django.core import serializers
from django.core.management.base import BaseCommand, CommandError
from django.core.management.utils import parse_apps_and_model_labels
from django.db import DEFAULT_DB_ALIAS, router
class ProxyModelWarning(Warning):
pass
class Command(BaseCommand):
help = (
"Output the contents of the database as a fixture of the given format "
"(using each model's default manager unless --all is specified)."
)
def add_arguments(self, parser):
parser.add_argument(
'args', metavar='app_label[.ModelName]', nargs='*',
help='Restricts dumped data to the specified app_label or app_label.ModelName.',
)
parser.add_argument(
'--format', default='json',
help='Specifies the output serialization format for fixtures.',
)
parser.add_argument(
'--indent', type=int,
help='Specifies the indent level to use when pretty-printing output.',
)
parser.add_argument(
'--database',
default=DEFAULT_DB_ALIAS,
help='Nominates a specific database to dump fixtures from. '
'Defaults to the "default" database.',
)
parser.add_argument(
'-e', '--exclude', action='append', default=[],
help='An app_label or app_label.ModelName to exclude '
'(use multiple --exclude to exclude multiple apps/models).',
)
parser.add_argument(
'--natural-foreign', action='store_true', dest='use_natural_foreign_keys',
help='Use natural foreign keys if they are available.',
)
parser.add_argument(
'--natural-primary', action='store_true', dest='use_natural_primary_keys',
help='Use natural primary keys if they are available.',
)
parser.add_argument(
'-a', '--all', action='store_true', dest='use_base_manager',
help="Use Django's base manager to dump all models stored in the database, "
"including those that would otherwise be filtered or modified by a custom manager.",
)
parser.add_argument(
'--pks', dest='primary_keys',
help="Only dump objects with given primary keys. Accepts a comma-separated "
"list of keys. This option only works when you specify one model.",
)
parser.add_argument(
'-o', '--output',
help='Specifies file to which the output is written.'
)
def handle(self, *app_labels, **options):
format = options['format']
indent = options['indent']
using = options['database']
excludes = options['exclude']
output = options['output']
show_traceback = options['traceback']
use_natural_foreign_keys = options['use_natural_foreign_keys']
use_natural_primary_keys = options['use_natural_primary_keys']
use_base_manager = options['use_base_manager']
pks = options['primary_keys']
if pks:
primary_keys = [pk.strip() for pk in pks.split(',')]
else:
primary_keys = []
excluded_models, excluded_apps = parse_apps_and_model_labels(excludes)
if not app_labels:
if primary_keys:
raise CommandError("You can only use --pks option with one model")
app_list = dict.fromkeys(
app_config for app_config in apps.get_app_configs()
if app_config.models_module is not None and app_config not in excluded_apps
)
else:
if len(app_labels) > 1 and primary_keys:
raise CommandError("You can only use --pks option with one model")
app_list = {}
for label in app_labels:
try:
app_label, model_label = label.split('.')
try:
app_config = apps.get_app_config(app_label)
except LookupError as e:
raise CommandError(str(e))
if app_config.models_module is None or app_config in excluded_apps:
continue
try:
model = app_config.get_model(model_label)
except LookupError:
raise CommandError("Unknown model: %s.%s" % (app_label, model_label))
app_list_value = app_list.setdefault(app_config, [])
# We may have previously seen an "all-models" request for
# this app (no model qualifier was given). In this case
# there is no need adding specific models to the list.
if app_list_value is not None:
if model not in app_list_value:
app_list_value.append(model)
except ValueError:
if primary_keys:
raise CommandError("You can only use --pks option with one model")
# This is just an app - no model qualifier
app_label = label
try:
app_config = apps.get_app_config(app_label)
except LookupError as e:
raise CommandError(str(e))
if app_config.models_module is None or app_config in excluded_apps:
continue
app_list[app_config] = None
# Check that the serialization format exists; this is a shortcut to
# avoid collating all the objects and _then_ failing.
if format not in serializers.get_public_serializer_formats():
try:
serializers.get_serializer(format)
except serializers.SerializerDoesNotExist:
pass
raise CommandError("Unknown serialization format: %s" % format)
def get_objects(count_only=False):
"""
Collate the objects to be serialized. If count_only is True, just
count the number of objects to be serialized.
"""
if use_natural_foreign_keys:
models = serializers.sort_dependencies(app_list.items(), allow_cycles=True)
else:
# There is no need to sort dependencies when natural foreign
# keys are not used.
models = []
for (app_config, model_list) in app_list.items():
if model_list is None:
models.extend(app_config.get_models())
else:
models.extend(model_list)
for model in models:
if model in excluded_models:
continue
if model._meta.proxy and model._meta.proxy_for_model not in models:
warnings.warn(
"%s is a proxy model and won't be serialized." % model._meta.label,
category=ProxyModelWarning,
)
if not model._meta.proxy and router.allow_migrate_model(using, model):
if use_base_manager:
objects = model._base_manager
else:
objects = model._default_manager
queryset = objects.using(using).order_by(model._meta.pk.name)
if primary_keys:
queryset = queryset.filter(pk__in=primary_keys)
if count_only:
yield queryset.order_by().count()
else:
yield from queryset.iterator()
try:
self.stdout.ending = None
progress_output = None
object_count = 0
# If dumpdata is outputting to stdout, there is no way to display progress
if output and self.stdout.isatty() and options['verbosity'] > 0:
progress_output = self.stdout
object_count = sum(get_objects(count_only=True))
stream = open(output, 'w') if output else None
try:
serializers.serialize(
format, get_objects(), indent=indent,
use_natural_foreign_keys=use_natural_foreign_keys,
use_natural_primary_keys=use_natural_primary_keys,
stream=stream or self.stdout, progress_output=progress_output,
object_count=object_count,
)
finally:
if stream:
stream.close()
except Exception as e:
if show_traceback:
raise
raise CommandError("Unable to serialize database: %s" % e)
|
75ea755e299279dd563fa7ac499274e2ab6eae73b3bc360a780acabec16d500b | import errno
import os
import re
import socket
import sys
from datetime import datetime
from django.conf import settings
from django.core.management.base import BaseCommand, CommandError
from django.core.servers.basehttp import (
WSGIServer, get_internal_wsgi_application, run,
)
from django.utils import autoreload
from django.utils.regex_helper import _lazy_re_compile
naiveip_re = _lazy_re_compile(r"""^(?:
(?P<addr>
(?P<ipv4>\d{1,3}(?:\.\d{1,3}){3}) | # IPv4 address
(?P<ipv6>\[[a-fA-F0-9:]+\]) | # IPv6 address
(?P<fqdn>[a-zA-Z0-9-]+(?:\.[a-zA-Z0-9-]+)*) # FQDN
):)?(?P<port>\d+)$""", re.X)
class Command(BaseCommand):
help = "Starts a lightweight Web server for development."
# Validation is called explicitly each time the server is reloaded.
requires_system_checks = False
stealth_options = ('shutdown_message',)
default_addr = '127.0.0.1'
default_addr_ipv6 = '::1'
default_port = '8000'
protocol = 'http'
server_cls = WSGIServer
def add_arguments(self, parser):
parser.add_argument(
'addrport', nargs='?',
help='Optional port number, or ipaddr:port'
)
parser.add_argument(
'--ipv6', '-6', action='store_true', dest='use_ipv6',
help='Tells Django to use an IPv6 address.',
)
parser.add_argument(
'--nothreading', action='store_false', dest='use_threading',
help='Tells Django to NOT use threading.',
)
parser.add_argument(
'--noreload', action='store_false', dest='use_reloader',
help='Tells Django to NOT use the auto-reloader.',
)
def execute(self, *args, **options):
if options['no_color']:
# We rely on the environment because it's currently the only
# way to reach WSGIRequestHandler. This seems an acceptable
# compromise considering `runserver` runs indefinitely.
os.environ["DJANGO_COLORS"] = "nocolor"
super().execute(*args, **options)
def get_handler(self, *args, **options):
"""Return the default WSGI handler for the runner."""
return get_internal_wsgi_application()
def handle(self, *args, **options):
if not settings.DEBUG and not settings.ALLOWED_HOSTS:
raise CommandError('You must set settings.ALLOWED_HOSTS if DEBUG is False.')
self.use_ipv6 = options['use_ipv6']
if self.use_ipv6 and not socket.has_ipv6:
raise CommandError('Your Python does not support IPv6.')
self._raw_ipv6 = False
if not options['addrport']:
self.addr = ''
self.port = self.default_port
else:
m = re.match(naiveip_re, options['addrport'])
if m is None:
raise CommandError('"%s" is not a valid port number '
'or address:port pair.' % options['addrport'])
self.addr, _ipv4, _ipv6, _fqdn, self.port = m.groups()
if not self.port.isdigit():
raise CommandError("%r is not a valid port number." % self.port)
if self.addr:
if _ipv6:
self.addr = self.addr[1:-1]
self.use_ipv6 = True
self._raw_ipv6 = True
elif self.use_ipv6 and not _fqdn:
raise CommandError('"%s" is not a valid IPv6 address.' % self.addr)
if not self.addr:
self.addr = self.default_addr_ipv6 if self.use_ipv6 else self.default_addr
self._raw_ipv6 = self.use_ipv6
self.run(**options)
def run(self, **options):
"""Run the server, using the autoreloader if needed."""
use_reloader = options['use_reloader']
if use_reloader:
autoreload.run_with_reloader(self.inner_run, **options)
else:
self.inner_run(None, **options)
def inner_run(self, *args, **options):
# If an exception was silenced in ManagementUtility.execute in order
# to be raised in the child process, raise it now.
autoreload.raise_last_exception()
threading = options['use_threading']
# 'shutdown_message' is a stealth option.
shutdown_message = options.get('shutdown_message', '')
quit_command = 'CTRL-BREAK' if sys.platform == 'win32' else 'CONTROL-C'
self.stdout.write("Performing system checks...\n\n")
self.check(display_num_errors=True)
# Need to check migrations here, so can't use the
# requires_migrations_check attribute.
self.check_migrations()
now = datetime.now().strftime('%B %d, %Y - %X')
self.stdout.write(now)
self.stdout.write((
"Django version %(version)s, using settings %(settings)r\n"
"Starting development server at %(protocol)s://%(addr)s:%(port)s/\n"
"Quit the server with %(quit_command)s."
) % {
"version": self.get_version(),
"settings": settings.SETTINGS_MODULE,
"protocol": self.protocol,
"addr": '[%s]' % self.addr if self._raw_ipv6 else self.addr,
"port": self.port,
"quit_command": quit_command,
})
try:
handler = self.get_handler(*args, **options)
run(self.addr, int(self.port), handler,
ipv6=self.use_ipv6, threading=threading, server_cls=self.server_cls)
except OSError as e:
# Use helpful error messages instead of ugly tracebacks.
ERRORS = {
errno.EACCES: "You don't have permission to access that port.",
errno.EADDRINUSE: "That port is already in use.",
errno.EADDRNOTAVAIL: "That IP address can't be assigned to.",
}
try:
error_text = ERRORS[e.errno]
except KeyError:
error_text = e
self.stderr.write("Error: %s" % error_text)
# Need to use an OS exit because sys.exit doesn't work in a thread
os._exit(1)
except KeyboardInterrupt:
if shutdown_message:
self.stdout.write(shutdown_message)
sys.exit(0)
|
4e329f462e5ffe85c926c4d2e5ad33e52f513fe3de6f4d03a9ffee6a225d1478 | from django.apps import apps
from django.conf import settings
from django.core.management.base import BaseCommand, CommandError
from django.db import DEFAULT_DB_ALIAS, connections, migrations
from django.db.migrations.loader import AmbiguityError, MigrationLoader
from django.db.migrations.migration import SwappableTuple
from django.db.migrations.optimizer import MigrationOptimizer
from django.db.migrations.writer import MigrationWriter
from django.utils.version import get_docs_version
class Command(BaseCommand):
help = "Squashes an existing set of migrations (from first until specified) into a single new one."
def add_arguments(self, parser):
parser.add_argument(
'app_label',
help='App label of the application to squash migrations for.',
)
parser.add_argument(
'start_migration_name', nargs='?',
help='Migrations will be squashed starting from and including this migration.',
)
parser.add_argument(
'migration_name',
help='Migrations will be squashed until and including this migration.',
)
parser.add_argument(
'--no-optimize', action='store_true',
help='Do not try to optimize the squashed operations.',
)
parser.add_argument(
'--noinput', '--no-input', action='store_false', dest='interactive',
help='Tells Django to NOT prompt the user for input of any kind.',
)
parser.add_argument(
'--squashed-name',
help='Sets the name of the new squashed migration.',
)
parser.add_argument(
'--no-header', action='store_false', dest='include_header',
help='Do not add a header comment to the new squashed migration.',
)
def handle(self, **options):
self.verbosity = options['verbosity']
self.interactive = options['interactive']
app_label = options['app_label']
start_migration_name = options['start_migration_name']
migration_name = options['migration_name']
no_optimize = options['no_optimize']
squashed_name = options['squashed_name']
include_header = options['include_header']
# Validate app_label.
try:
apps.get_app_config(app_label)
except LookupError as err:
raise CommandError(str(err))
# Load the current graph state, check the app and migration they asked for exists
loader = MigrationLoader(connections[DEFAULT_DB_ALIAS])
if app_label not in loader.migrated_apps:
raise CommandError(
"App '%s' does not have migrations (so squashmigrations on "
"it makes no sense)" % app_label
)
migration = self.find_migration(loader, app_label, migration_name)
# Work out the list of predecessor migrations
migrations_to_squash = [
loader.get_migration(al, mn)
for al, mn in loader.graph.forwards_plan((migration.app_label, migration.name))
if al == migration.app_label
]
if start_migration_name:
start_migration = self.find_migration(loader, app_label, start_migration_name)
start = loader.get_migration(start_migration.app_label, start_migration.name)
try:
start_index = migrations_to_squash.index(start)
migrations_to_squash = migrations_to_squash[start_index:]
except ValueError:
raise CommandError(
"The migration '%s' cannot be found. Maybe it comes after "
"the migration '%s'?\n"
"Have a look at:\n"
" python manage.py showmigrations %s\n"
"to debug this issue." % (start_migration, migration, app_label)
)
# Tell them what we're doing and optionally ask if we should proceed
if self.verbosity > 0 or self.interactive:
self.stdout.write(self.style.MIGRATE_HEADING("Will squash the following migrations:"))
for migration in migrations_to_squash:
self.stdout.write(" - %s" % migration.name)
if self.interactive:
answer = None
while not answer or answer not in "yn":
answer = input("Do you wish to proceed? [yN] ")
if not answer:
answer = "n"
break
else:
answer = answer[0].lower()
if answer != "y":
return
# Load the operations from all those migrations and concat together,
# along with collecting external dependencies and detecting
# double-squashing
operations = []
dependencies = set()
# We need to take all dependencies from the first migration in the list
# as it may be 0002 depending on 0001
first_migration = True
for smigration in migrations_to_squash:
if smigration.replaces:
raise CommandError(
"You cannot squash squashed migrations! Please transition "
"it to a normal migration first: "
"https://docs.djangoproject.com/en/%s/topics/migrations/#squashing-migrations" % get_docs_version()
)
operations.extend(smigration.operations)
for dependency in smigration.dependencies:
if isinstance(dependency, SwappableTuple):
if settings.AUTH_USER_MODEL == dependency.setting:
dependencies.add(("__setting__", "AUTH_USER_MODEL"))
else:
dependencies.add(dependency)
elif dependency[0] != smigration.app_label or first_migration:
dependencies.add(dependency)
first_migration = False
if no_optimize:
if self.verbosity > 0:
self.stdout.write(self.style.MIGRATE_HEADING("(Skipping optimization.)"))
new_operations = operations
else:
if self.verbosity > 0:
self.stdout.write(self.style.MIGRATE_HEADING("Optimizing..."))
optimizer = MigrationOptimizer()
new_operations = optimizer.optimize(operations, migration.app_label)
if self.verbosity > 0:
if len(new_operations) == len(operations):
self.stdout.write(" No optimizations possible.")
else:
self.stdout.write(
" Optimized from %s operations to %s operations." %
(len(operations), len(new_operations))
)
# Work out the value of replaces (any squashed ones we're re-squashing)
# need to feed their replaces into ours
replaces = []
for migration in migrations_to_squash:
if migration.replaces:
replaces.extend(migration.replaces)
else:
replaces.append((migration.app_label, migration.name))
# Make a new migration with those operations
subclass = type("Migration", (migrations.Migration,), {
"dependencies": dependencies,
"operations": new_operations,
"replaces": replaces,
})
if start_migration_name:
if squashed_name:
# Use the name from --squashed-name.
prefix, _ = start_migration.name.split('_', 1)
name = '%s_%s' % (prefix, squashed_name)
else:
# Generate a name.
name = '%s_squashed_%s' % (start_migration.name, migration.name)
new_migration = subclass(name, app_label)
else:
name = '0001_%s' % (squashed_name or 'squashed_%s' % migration.name)
new_migration = subclass(name, app_label)
new_migration.initial = True
# Write out the new migration file
writer = MigrationWriter(new_migration, include_header)
with open(writer.path, "w", encoding='utf-8') as fh:
fh.write(writer.as_string())
if self.verbosity > 0:
self.stdout.write(
self.style.MIGRATE_HEADING('Created new squashed migration %s' % writer.path) + '\n'
' You should commit this migration but leave the old ones in place;\n'
' the new migration will be used for new installs. Once you are sure\n'
' all instances of the codebase have applied the migrations you squashed,\n'
' you can delete them.'
)
if writer.needs_manual_porting:
self.stdout.write(
self.style.MIGRATE_HEADING('Manual porting required') + '\n'
' Your migrations contained functions that must be manually copied over,\n'
' as we could not safely copy their implementation.\n'
' See the comment at the top of the squashed migration for details.'
)
def find_migration(self, loader, app_label, name):
try:
return loader.get_migration_by_prefix(app_label, name)
except AmbiguityError:
raise CommandError(
"More than one migration matches '%s' in app '%s'. Please be "
"more specific." % (name, app_label)
)
except KeyError:
raise CommandError(
"Cannot find a migration matching '%s' from app '%s'." %
(name, app_label)
)
|
a6a1cff9f44586730dd800021dd2420a4fcbe97c157277acb2098769fd34909f | import codecs
import concurrent.futures
import glob
import os
from django.core.management.base import BaseCommand, CommandError
from django.core.management.utils import (
find_command, is_ignored_path, popen_wrapper,
)
def has_bom(fn):
with open(fn, 'rb') as f:
sample = f.read(4)
return sample.startswith((codecs.BOM_UTF8, codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE))
def is_writable(path):
# Known side effect: updating file access/modified time to current time if
# it is writable.
try:
with open(path, 'a'):
os.utime(path, None)
except OSError:
return False
return True
class Command(BaseCommand):
help = 'Compiles .po files to .mo files for use with builtin gettext support.'
requires_system_checks = False
program = 'msgfmt'
program_options = ['--check-format']
def add_arguments(self, parser):
parser.add_argument(
'--locale', '-l', action='append', default=[],
help='Locale(s) to process (e.g. de_AT). Default is to process all. '
'Can be used multiple times.',
)
parser.add_argument(
'--exclude', '-x', action='append', default=[],
help='Locales to exclude. Default is none. Can be used multiple times.',
)
parser.add_argument(
'--use-fuzzy', '-f', dest='fuzzy', action='store_true',
help='Use fuzzy translations.',
)
parser.add_argument(
'--ignore', '-i', action='append', dest='ignore_patterns',
default=[], metavar='PATTERN',
help='Ignore directories matching this glob-style pattern. '
'Use multiple times to ignore more.',
)
def handle(self, **options):
locale = options['locale']
exclude = options['exclude']
ignore_patterns = set(options['ignore_patterns'])
self.verbosity = options['verbosity']
if options['fuzzy']:
self.program_options = self.program_options + ['-f']
if find_command(self.program) is None:
raise CommandError("Can't find %s. Make sure you have GNU gettext "
"tools 0.15 or newer installed." % self.program)
basedirs = [os.path.join('conf', 'locale'), 'locale']
if os.environ.get('DJANGO_SETTINGS_MODULE'):
from django.conf import settings
basedirs.extend(settings.LOCALE_PATHS)
# Walk entire tree, looking for locale directories
for dirpath, dirnames, filenames in os.walk('.', topdown=True):
for dirname in dirnames:
if is_ignored_path(os.path.normpath(os.path.join(dirpath, dirname)), ignore_patterns):
dirnames.remove(dirname)
elif dirname == 'locale':
basedirs.append(os.path.join(dirpath, dirname))
# Gather existing directories.
basedirs = set(map(os.path.abspath, filter(os.path.isdir, basedirs)))
if not basedirs:
raise CommandError("This script should be run from the Django Git "
"checkout or your project or app tree, or with "
"the settings module specified.")
# Build locale list
all_locales = []
for basedir in basedirs:
locale_dirs = filter(os.path.isdir, glob.glob('%s/*' % basedir))
all_locales.extend(map(os.path.basename, locale_dirs))
# Account for excluded locales
locales = locale or all_locales
locales = set(locales).difference(exclude)
self.has_errors = False
for basedir in basedirs:
if locales:
dirs = [os.path.join(basedir, l, 'LC_MESSAGES') for l in locales]
else:
dirs = [basedir]
locations = []
for ldir in dirs:
for dirpath, dirnames, filenames in os.walk(ldir):
locations.extend((dirpath, f) for f in filenames if f.endswith('.po'))
if locations:
self.compile_messages(locations)
if self.has_errors:
raise CommandError('compilemessages generated one or more errors.')
def compile_messages(self, locations):
"""
Locations is a list of tuples: [(directory, file), ...]
"""
with concurrent.futures.ThreadPoolExecutor() as executor:
futures = []
for i, (dirpath, f) in enumerate(locations):
if self.verbosity > 0:
self.stdout.write('processing file %s in %s' % (f, dirpath))
po_path = os.path.join(dirpath, f)
if has_bom(po_path):
self.stderr.write(
'The %s file has a BOM (Byte Order Mark). Django only '
'supports .po files encoded in UTF-8 and without any BOM.' % po_path
)
self.has_errors = True
continue
base_path = os.path.splitext(po_path)[0]
# Check writability on first location
if i == 0 and not is_writable(base_path + '.mo'):
self.stderr.write(
'The po files under %s are in a seemingly not writable location. '
'mo files will not be updated/created.' % dirpath
)
self.has_errors = True
return
args = [self.program] + self.program_options + [
'-o', base_path + '.mo', base_path + '.po'
]
futures.append(executor.submit(popen_wrapper, args))
for future in concurrent.futures.as_completed(futures):
output, errors, status = future.result()
if status:
if self.verbosity > 0:
if errors:
self.stderr.write("Execution of %s failed: %s" % (self.program, errors))
else:
self.stderr.write("Execution of %s failed" % self.program)
self.has_errors = True
|
56d5d42a2d7da4b9cf5d66644830ab9829d229f5007c9650d8c13ea0ce3ae416 | import functools
import glob
import gzip
import os
import sys
import warnings
import zipfile
from itertools import product
from django.apps import apps
from django.conf import settings
from django.core import serializers
from django.core.exceptions import ImproperlyConfigured
from django.core.management.base import BaseCommand, CommandError
from django.core.management.color import no_style
from django.core.management.utils import parse_apps_and_model_labels
from django.db import (
DEFAULT_DB_ALIAS, DatabaseError, IntegrityError, connections, router,
transaction,
)
from django.utils.functional import cached_property
try:
import bz2
has_bz2 = True
except ImportError:
has_bz2 = False
READ_STDIN = '-'
class Command(BaseCommand):
help = 'Installs the named fixture(s) in the database.'
missing_args_message = (
"No database fixture specified. Please provide the path of at least "
"one fixture in the command line."
)
def add_arguments(self, parser):
parser.add_argument('args', metavar='fixture', nargs='+', help='Fixture labels.')
parser.add_argument(
'--database', default=DEFAULT_DB_ALIAS,
help='Nominates a specific database to load fixtures into. Defaults to the "default" database.',
)
parser.add_argument(
'--app', dest='app_label',
help='Only look for fixtures in the specified app.',
)
parser.add_argument(
'--ignorenonexistent', '-i', action='store_true', dest='ignore',
help='Ignores entries in the serialized data for fields that do not '
'currently exist on the model.',
)
parser.add_argument(
'-e', '--exclude', action='append', default=[],
help='An app_label or app_label.ModelName to exclude. Can be used multiple times.',
)
parser.add_argument(
'--format',
help='Format of serialized data when reading from stdin.',
)
def handle(self, *fixture_labels, **options):
self.ignore = options['ignore']
self.using = options['database']
self.app_label = options['app_label']
self.verbosity = options['verbosity']
self.excluded_models, self.excluded_apps = parse_apps_and_model_labels(options['exclude'])
self.format = options['format']
with transaction.atomic(using=self.using):
self.loaddata(fixture_labels)
# Close the DB connection -- unless we're still in a transaction. This
# is required as a workaround for an edge case in MySQL: if the same
# connection is used to create tables, load data, and query, the query
# can return incorrect results. See Django #7572, MySQL #37735.
if transaction.get_autocommit(self.using):
connections[self.using].close()
def loaddata(self, fixture_labels):
connection = connections[self.using]
# Keep a count of the installed objects and fixtures
self.fixture_count = 0
self.loaded_object_count = 0
self.fixture_object_count = 0
self.models = set()
self.serialization_formats = serializers.get_public_serializer_formats()
# Forcing binary mode may be revisited after dropping Python 2 support (see #22399)
self.compression_formats = {
None: (open, 'rb'),
'gz': (gzip.GzipFile, 'rb'),
'zip': (SingleZipReader, 'r'),
'stdin': (lambda *args: sys.stdin, None),
}
if has_bz2:
self.compression_formats['bz2'] = (bz2.BZ2File, 'r')
# Django's test suite repeatedly tries to load initial_data fixtures
# from apps that don't have any fixtures. Because disabling constraint
# checks can be expensive on some database (especially MSSQL), bail
# out early if no fixtures are found.
for fixture_label in fixture_labels:
if self.find_fixtures(fixture_label):
break
else:
return
with connection.constraint_checks_disabled():
self.objs_with_deferred_fields = []
for fixture_label in fixture_labels:
self.load_label(fixture_label)
for obj in self.objs_with_deferred_fields:
obj.save_deferred_fields(using=self.using)
# Since we disabled constraint checks, we must manually check for
# any invalid keys that might have been added
table_names = [model._meta.db_table for model in self.models]
try:
connection.check_constraints(table_names=table_names)
except Exception as e:
e.args = ("Problem installing fixtures: %s" % e,)
raise
# If we found even one object in a fixture, we need to reset the
# database sequences.
if self.loaded_object_count > 0:
sequence_sql = connection.ops.sequence_reset_sql(no_style(), self.models)
if sequence_sql:
if self.verbosity >= 2:
self.stdout.write('Resetting sequences')
with connection.cursor() as cursor:
for line in sequence_sql:
cursor.execute(line)
if self.verbosity >= 1:
if self.fixture_object_count == self.loaded_object_count:
self.stdout.write(
"Installed %d object(s) from %d fixture(s)"
% (self.loaded_object_count, self.fixture_count)
)
else:
self.stdout.write(
"Installed %d object(s) (of %d) from %d fixture(s)"
% (self.loaded_object_count, self.fixture_object_count, self.fixture_count)
)
def load_label(self, fixture_label):
"""Load fixtures files for a given label."""
show_progress = self.verbosity >= 3
for fixture_file, fixture_dir, fixture_name in self.find_fixtures(fixture_label):
_, ser_fmt, cmp_fmt = self.parse_name(os.path.basename(fixture_file))
open_method, mode = self.compression_formats[cmp_fmt]
fixture = open_method(fixture_file, mode)
try:
self.fixture_count += 1
objects_in_fixture = 0
loaded_objects_in_fixture = 0
if self.verbosity >= 2:
self.stdout.write(
"Installing %s fixture '%s' from %s."
% (ser_fmt, fixture_name, humanize(fixture_dir))
)
objects = serializers.deserialize(
ser_fmt, fixture, using=self.using, ignorenonexistent=self.ignore,
handle_forward_references=True,
)
for obj in objects:
objects_in_fixture += 1
if (obj.object._meta.app_config in self.excluded_apps or
type(obj.object) in self.excluded_models):
continue
if router.allow_migrate_model(self.using, obj.object.__class__):
loaded_objects_in_fixture += 1
self.models.add(obj.object.__class__)
try:
obj.save(using=self.using)
if show_progress:
self.stdout.write(
'\rProcessed %i object(s).' % loaded_objects_in_fixture,
ending=''
)
# psycopg2 raises ValueError if data contains NUL chars.
except (DatabaseError, IntegrityError, ValueError) as e:
e.args = ("Could not load %(app_label)s.%(object_name)s(pk=%(pk)s): %(error_msg)s" % {
'app_label': obj.object._meta.app_label,
'object_name': obj.object._meta.object_name,
'pk': obj.object.pk,
'error_msg': e,
},)
raise
if obj.deferred_fields:
self.objs_with_deferred_fields.append(obj)
if objects and show_progress:
self.stdout.write() # Add a newline after progress indicator.
self.loaded_object_count += loaded_objects_in_fixture
self.fixture_object_count += objects_in_fixture
except Exception as e:
if not isinstance(e, CommandError):
e.args = ("Problem installing fixture '%s': %s" % (fixture_file, e),)
raise
finally:
fixture.close()
# Warn if the fixture we loaded contains 0 objects.
if objects_in_fixture == 0:
warnings.warn(
"No fixture data found for '%s'. (File format may be "
"invalid.)" % fixture_name,
RuntimeWarning
)
@functools.lru_cache(maxsize=None)
def find_fixtures(self, fixture_label):
"""Find fixture files for a given label."""
if fixture_label == READ_STDIN:
return [(READ_STDIN, None, READ_STDIN)]
fixture_name, ser_fmt, cmp_fmt = self.parse_name(fixture_label)
databases = [self.using, None]
cmp_fmts = list(self.compression_formats) if cmp_fmt is None else [cmp_fmt]
ser_fmts = serializers.get_public_serializer_formats() if ser_fmt is None else [ser_fmt]
if self.verbosity >= 2:
self.stdout.write("Loading '%s' fixtures..." % fixture_name)
if os.path.isabs(fixture_name):
fixture_dirs = [os.path.dirname(fixture_name)]
fixture_name = os.path.basename(fixture_name)
else:
fixture_dirs = self.fixture_dirs
if os.path.sep in os.path.normpath(fixture_name):
fixture_dirs = [os.path.join(dir_, os.path.dirname(fixture_name))
for dir_ in fixture_dirs]
fixture_name = os.path.basename(fixture_name)
suffixes = (
'.'.join(ext for ext in combo if ext)
for combo in product(databases, ser_fmts, cmp_fmts)
)
targets = {'.'.join((fixture_name, suffix)) for suffix in suffixes}
fixture_files = []
for fixture_dir in fixture_dirs:
if self.verbosity >= 2:
self.stdout.write("Checking %s for fixtures..." % humanize(fixture_dir))
fixture_files_in_dir = []
path = os.path.join(fixture_dir, fixture_name)
for candidate in glob.iglob(glob.escape(path) + '*'):
if os.path.basename(candidate) in targets:
# Save the fixture_dir and fixture_name for future error messages.
fixture_files_in_dir.append((candidate, fixture_dir, fixture_name))
if self.verbosity >= 2 and not fixture_files_in_dir:
self.stdout.write("No fixture '%s' in %s." %
(fixture_name, humanize(fixture_dir)))
# Check kept for backwards-compatibility; it isn't clear why
# duplicates are only allowed in different directories.
if len(fixture_files_in_dir) > 1:
raise CommandError(
"Multiple fixtures named '%s' in %s. Aborting." %
(fixture_name, humanize(fixture_dir)))
fixture_files.extend(fixture_files_in_dir)
if not fixture_files:
raise CommandError("No fixture named '%s' found." % fixture_name)
return fixture_files
@cached_property
def fixture_dirs(self):
"""
Return a list of fixture directories.
The list contains the 'fixtures' subdirectory of each installed
application, if it exists, the directories in FIXTURE_DIRS, and the
current directory.
"""
dirs = []
fixture_dirs = settings.FIXTURE_DIRS
if len(fixture_dirs) != len(set(fixture_dirs)):
raise ImproperlyConfigured("settings.FIXTURE_DIRS contains duplicates.")
for app_config in apps.get_app_configs():
app_label = app_config.label
app_dir = os.path.join(app_config.path, 'fixtures')
if app_dir in fixture_dirs:
raise ImproperlyConfigured(
"'%s' is a default fixture directory for the '%s' app "
"and cannot be listed in settings.FIXTURE_DIRS." % (app_dir, app_label)
)
if self.app_label and app_label != self.app_label:
continue
if os.path.isdir(app_dir):
dirs.append(app_dir)
dirs.extend(fixture_dirs)
dirs.append('')
return [os.path.realpath(d) for d in dirs]
def parse_name(self, fixture_name):
"""
Split fixture name in name, serialization format, compression format.
"""
if fixture_name == READ_STDIN:
if not self.format:
raise CommandError('--format must be specified when reading from stdin.')
return READ_STDIN, self.format, 'stdin'
parts = fixture_name.rsplit('.', 2)
if len(parts) > 1 and parts[-1] in self.compression_formats:
cmp_fmt = parts[-1]
parts = parts[:-1]
else:
cmp_fmt = None
if len(parts) > 1:
if parts[-1] in self.serialization_formats:
ser_fmt = parts[-1]
parts = parts[:-1]
else:
raise CommandError(
"Problem installing fixture '%s': %s is not a known "
"serialization format." % ('.'.join(parts[:-1]), parts[-1]))
else:
ser_fmt = None
name = '.'.join(parts)
return name, ser_fmt, cmp_fmt
class SingleZipReader(zipfile.ZipFile):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
if len(self.namelist()) != 1:
raise ValueError("Zip-compressed fixtures must contain one file.")
def read(self):
return zipfile.ZipFile.read(self, self.namelist()[0])
def humanize(dirname):
return "'%s'" % dirname if dirname else 'absolute path'
|
a07fea28c86c11c9de8a6d3226005e347ab8eb1537996716a5e71e2b67289179 | from django.conf import settings
from django.core.cache import caches
from django.core.cache.backends.db import BaseDatabaseCache
from django.core.management.base import BaseCommand, CommandError
from django.db import (
DEFAULT_DB_ALIAS, DatabaseError, connections, models, router, transaction,
)
class Command(BaseCommand):
help = "Creates the tables needed to use the SQL cache backend."
requires_system_checks = False
def add_arguments(self, parser):
parser.add_argument(
'args', metavar='table_name', nargs='*',
help='Optional table names. Otherwise, settings.CACHES is used to find cache tables.',
)
parser.add_argument(
'--database',
default=DEFAULT_DB_ALIAS,
help='Nominates a database onto which the cache tables will be '
'installed. Defaults to the "default" database.',
)
parser.add_argument(
'--dry-run', action='store_true',
help='Does not create the table, just prints the SQL that would be run.',
)
def handle(self, *tablenames, **options):
db = options['database']
self.verbosity = options['verbosity']
dry_run = options['dry_run']
if tablenames:
# Legacy behavior, tablename specified as argument
for tablename in tablenames:
self.create_table(db, tablename, dry_run)
else:
for cache_alias in settings.CACHES:
cache = caches[cache_alias]
if isinstance(cache, BaseDatabaseCache):
self.create_table(db, cache._table, dry_run)
def create_table(self, database, tablename, dry_run):
cache = BaseDatabaseCache(tablename, {})
if not router.allow_migrate_model(database, cache.cache_model_class):
return
connection = connections[database]
if tablename in connection.introspection.table_names():
if self.verbosity > 0:
self.stdout.write("Cache table '%s' already exists." % tablename)
return
fields = (
# "key" is a reserved word in MySQL, so use "cache_key" instead.
models.CharField(name='cache_key', max_length=255, unique=True, primary_key=True),
models.TextField(name='value'),
models.DateTimeField(name='expires', db_index=True),
)
table_output = []
index_output = []
qn = connection.ops.quote_name
for f in fields:
field_output = [
qn(f.name),
f.db_type(connection=connection),
'%sNULL' % ('NOT ' if not f.null else ''),
]
if f.primary_key:
field_output.append("PRIMARY KEY")
elif f.unique:
field_output.append("UNIQUE")
if f.db_index:
unique = "UNIQUE " if f.unique else ""
index_output.append(
"CREATE %sINDEX %s ON %s (%s);" %
(unique, qn('%s_%s' % (tablename, f.name)), qn(tablename), qn(f.name))
)
table_output.append(" ".join(field_output))
full_statement = ["CREATE TABLE %s (" % qn(tablename)]
for i, line in enumerate(table_output):
full_statement.append(' %s%s' % (line, ',' if i < len(table_output) - 1 else ''))
full_statement.append(');')
full_statement = "\n".join(full_statement)
if dry_run:
self.stdout.write(full_statement)
for statement in index_output:
self.stdout.write(statement)
return
with transaction.atomic(using=database, savepoint=connection.features.can_rollback_ddl):
with connection.cursor() as curs:
try:
curs.execute(full_statement)
except DatabaseError as e:
raise CommandError(
"Cache table '%s' could not be created.\nThe error was: %s." %
(tablename, e))
for statement in index_output:
curs.execute(statement)
if self.verbosity > 1:
self.stdout.write("Cache table '%s' created." % tablename)
|
c1c49f41a9bcdf8828df55b3ec19b3afb67717e879a004f1f1935a7b7c4ea28c | import subprocess
from django.core.management.base import BaseCommand, CommandError
from django.db import DEFAULT_DB_ALIAS, connections
class Command(BaseCommand):
help = (
"Runs the command-line client for specified database, or the "
"default database if none is provided."
)
requires_system_checks = False
def add_arguments(self, parser):
parser.add_argument(
'--database', default=DEFAULT_DB_ALIAS,
help='Nominates a database onto which to open a shell. Defaults to the "default" database.',
)
parameters = parser.add_argument_group('parameters', prefix_chars='--')
parameters.add_argument('parameters', nargs='*')
def handle(self, **options):
connection = connections[options['database']]
try:
connection.client.runshell(options['parameters'])
except FileNotFoundError:
# Note that we're assuming the FileNotFoundError relates to the
# command missing. It could be raised for some other reason, in
# which case this error message would be inaccurate. Still, this
# message catches the common case.
raise CommandError(
'You appear not to have the %r program installed or on your path.' %
connection.client.executable_name
)
except subprocess.CalledProcessError as e:
raise CommandError(
'"%s" returned non-zero exit status %s.' % (
' '.join(e.cmd),
e.returncode,
),
returncode=e.returncode,
)
|
a8150f9c2b2a662bbe2f187ed549f729f4f99150db3621f35e07527698cd64aa | import glob
import os
import re
import sys
from functools import total_ordering
from itertools import dropwhile
import django
from django.conf import settings
from django.core.exceptions import ImproperlyConfigured
from django.core.files.temp import NamedTemporaryFile
from django.core.management.base import BaseCommand, CommandError
from django.core.management.utils import (
find_command, handle_extensions, is_ignored_path, popen_wrapper,
)
from django.utils.encoding import DEFAULT_LOCALE_ENCODING
from django.utils.functional import cached_property
from django.utils.jslex import prepare_js_for_gettext
from django.utils.regex_helper import _lazy_re_compile
from django.utils.text import get_text_list
from django.utils.translation import templatize
plural_forms_re = _lazy_re_compile(r'^(?P<value>"Plural-Forms.+?\\n")\s*$', re.MULTILINE | re.DOTALL)
STATUS_OK = 0
NO_LOCALE_DIR = object()
def check_programs(*programs):
for program in programs:
if find_command(program) is None:
raise CommandError(
"Can't find %s. Make sure you have GNU gettext tools 0.15 or "
"newer installed." % program
)
@total_ordering
class TranslatableFile:
def __init__(self, dirpath, file_name, locale_dir):
self.file = file_name
self.dirpath = dirpath
self.locale_dir = locale_dir
def __repr__(self):
return "<%s: %s>" % (
self.__class__.__name__,
os.sep.join([self.dirpath, self.file]),
)
def __eq__(self, other):
return self.path == other.path
def __lt__(self, other):
return self.path < other.path
@property
def path(self):
return os.path.join(self.dirpath, self.file)
class BuildFile:
"""
Represent the state of a translatable file during the build process.
"""
def __init__(self, command, domain, translatable):
self.command = command
self.domain = domain
self.translatable = translatable
@cached_property
def is_templatized(self):
if self.domain == 'djangojs':
return self.command.gettext_version < (0, 18, 3)
elif self.domain == 'django':
file_ext = os.path.splitext(self.translatable.file)[1]
return file_ext != '.py'
return False
@cached_property
def path(self):
return self.translatable.path
@cached_property
def work_path(self):
"""
Path to a file which is being fed into GNU gettext pipeline. This may
be either a translatable or its preprocessed version.
"""
if not self.is_templatized:
return self.path
extension = {
'djangojs': 'c',
'django': 'py',
}.get(self.domain)
filename = '%s.%s' % (self.translatable.file, extension)
return os.path.join(self.translatable.dirpath, filename)
def preprocess(self):
"""
Preprocess (if necessary) a translatable file before passing it to
xgettext GNU gettext utility.
"""
if not self.is_templatized:
return
with open(self.path, encoding='utf-8') as fp:
src_data = fp.read()
if self.domain == 'djangojs':
content = prepare_js_for_gettext(src_data)
elif self.domain == 'django':
content = templatize(src_data, origin=self.path[2:])
with open(self.work_path, 'w', encoding='utf-8') as fp:
fp.write(content)
def postprocess_messages(self, msgs):
"""
Postprocess messages generated by xgettext GNU gettext utility.
Transform paths as if these messages were generated from original
translatable files rather than from preprocessed versions.
"""
if not self.is_templatized:
return msgs
# Remove '.py' suffix
if os.name == 'nt':
# Preserve '.\' prefix on Windows to respect gettext behavior
old_path = self.work_path
new_path = self.path
else:
old_path = self.work_path[2:]
new_path = self.path[2:]
return re.sub(
r'^(#: .*)(' + re.escape(old_path) + r')',
lambda match: match.group().replace(old_path, new_path),
msgs,
flags=re.MULTILINE
)
def cleanup(self):
"""
Remove a preprocessed copy of a translatable file (if any).
"""
if self.is_templatized:
# This check is needed for the case of a symlinked file and its
# source being processed inside a single group (locale dir);
# removing either of those two removes both.
if os.path.exists(self.work_path):
os.unlink(self.work_path)
def normalize_eols(raw_contents):
"""
Take a block of raw text that will be passed through str.splitlines() to
get universal newlines treatment.
Return the resulting block of text with normalized `\n` EOL sequences ready
to be written to disk using current platform's native EOLs.
"""
lines_list = raw_contents.splitlines()
# Ensure last line has its EOL
if lines_list and lines_list[-1]:
lines_list.append('')
return '\n'.join(lines_list)
def write_pot_file(potfile, msgs):
"""
Write the `potfile` with the `msgs` contents, making sure its format is
valid.
"""
pot_lines = msgs.splitlines()
if os.path.exists(potfile):
# Strip the header
lines = dropwhile(len, pot_lines)
else:
lines = []
found, header_read = False, False
for line in pot_lines:
if not found and not header_read:
if 'charset=CHARSET' in line:
found = True
line = line.replace('charset=CHARSET', 'charset=UTF-8')
if not line and not found:
header_read = True
lines.append(line)
msgs = '\n'.join(lines)
# Force newlines of POT files to '\n' to work around
# https://savannah.gnu.org/bugs/index.php?52395
with open(potfile, 'a', encoding='utf-8', newline='\n') as fp:
fp.write(msgs)
class Command(BaseCommand):
help = (
"Runs over the entire source tree of the current directory and "
"pulls out all strings marked for translation. It creates (or updates) a message "
"file in the conf/locale (in the django tree) or locale (for projects and "
"applications) directory.\n\nYou must run this command with one of either the "
"--locale, --exclude, or --all options."
)
translatable_file_class = TranslatableFile
build_file_class = BuildFile
requires_system_checks = False
msgmerge_options = ['-q', '--previous']
msguniq_options = ['--to-code=utf-8']
msgattrib_options = ['--no-obsolete']
xgettext_options = ['--from-code=UTF-8', '--add-comments=Translators']
def add_arguments(self, parser):
parser.add_argument(
'--locale', '-l', default=[], action='append',
help='Creates or updates the message files for the given locale(s) (e.g. pt_BR). '
'Can be used multiple times.',
)
parser.add_argument(
'--exclude', '-x', default=[], action='append',
help='Locales to exclude. Default is none. Can be used multiple times.',
)
parser.add_argument(
'--domain', '-d', default='django',
help='The domain of the message files (default: "django").',
)
parser.add_argument(
'--all', '-a', action='store_true',
help='Updates the message files for all existing locales.',
)
parser.add_argument(
'--extension', '-e', dest='extensions', action='append',
help='The file extension(s) to examine (default: "html,txt,py", or "js" '
'if the domain is "djangojs"). Separate multiple extensions with '
'commas, or use -e multiple times.',
)
parser.add_argument(
'--symlinks', '-s', action='store_true',
help='Follows symlinks to directories when examining source code '
'and templates for translation strings.',
)
parser.add_argument(
'--ignore', '-i', action='append', dest='ignore_patterns',
default=[], metavar='PATTERN',
help='Ignore files or directories matching this glob-style pattern. '
'Use multiple times to ignore more.',
)
parser.add_argument(
'--no-default-ignore', action='store_false', dest='use_default_ignore_patterns',
help="Don't ignore the common glob-style patterns 'CVS', '.*', '*~' and '*.pyc'.",
)
parser.add_argument(
'--no-wrap', action='store_true',
help="Don't break long message lines into several lines.",
)
parser.add_argument(
'--no-location', action='store_true',
help="Don't write '#: filename:line' lines.",
)
parser.add_argument(
'--add-location',
choices=('full', 'file', 'never'), const='full', nargs='?',
help=(
"Controls '#: filename:line' lines. If the option is 'full' "
"(the default if not given), the lines include both file name "
"and line number. If it's 'file', the line number is omitted. If "
"it's 'never', the lines are suppressed (same as --no-location). "
"--add-location requires gettext 0.19 or newer."
),
)
parser.add_argument(
'--no-obsolete', action='store_true',
help="Remove obsolete message strings.",
)
parser.add_argument(
'--keep-pot', action='store_true',
help="Keep .pot file after making messages. Useful when debugging.",
)
def handle(self, *args, **options):
locale = options['locale']
exclude = options['exclude']
self.domain = options['domain']
self.verbosity = options['verbosity']
process_all = options['all']
extensions = options['extensions']
self.symlinks = options['symlinks']
ignore_patterns = options['ignore_patterns']
if options['use_default_ignore_patterns']:
ignore_patterns += ['CVS', '.*', '*~', '*.pyc']
self.ignore_patterns = list(set(ignore_patterns))
# Avoid messing with mutable class variables
if options['no_wrap']:
self.msgmerge_options = self.msgmerge_options[:] + ['--no-wrap']
self.msguniq_options = self.msguniq_options[:] + ['--no-wrap']
self.msgattrib_options = self.msgattrib_options[:] + ['--no-wrap']
self.xgettext_options = self.xgettext_options[:] + ['--no-wrap']
if options['no_location']:
self.msgmerge_options = self.msgmerge_options[:] + ['--no-location']
self.msguniq_options = self.msguniq_options[:] + ['--no-location']
self.msgattrib_options = self.msgattrib_options[:] + ['--no-location']
self.xgettext_options = self.xgettext_options[:] + ['--no-location']
if options['add_location']:
if self.gettext_version < (0, 19):
raise CommandError(
"The --add-location option requires gettext 0.19 or later. "
"You have %s." % '.'.join(str(x) for x in self.gettext_version)
)
arg_add_location = "--add-location=%s" % options['add_location']
self.msgmerge_options = self.msgmerge_options[:] + [arg_add_location]
self.msguniq_options = self.msguniq_options[:] + [arg_add_location]
self.msgattrib_options = self.msgattrib_options[:] + [arg_add_location]
self.xgettext_options = self.xgettext_options[:] + [arg_add_location]
self.no_obsolete = options['no_obsolete']
self.keep_pot = options['keep_pot']
if self.domain not in ('django', 'djangojs'):
raise CommandError("currently makemessages only supports domains "
"'django' and 'djangojs'")
if self.domain == 'djangojs':
exts = extensions or ['js']
else:
exts = extensions or ['html', 'txt', 'py']
self.extensions = handle_extensions(exts)
if (not locale and not exclude and not process_all) or self.domain is None:
raise CommandError(
"Type '%s help %s' for usage information."
% (os.path.basename(sys.argv[0]), sys.argv[1])
)
if self.verbosity > 1:
self.stdout.write(
'examining files with the extensions: %s'
% get_text_list(list(self.extensions), 'and')
)
self.invoked_for_django = False
self.locale_paths = []
self.default_locale_path = None
if os.path.isdir(os.path.join('conf', 'locale')):
self.locale_paths = [os.path.abspath(os.path.join('conf', 'locale'))]
self.default_locale_path = self.locale_paths[0]
self.invoked_for_django = True
else:
if self.settings_available:
self.locale_paths.extend(settings.LOCALE_PATHS)
# Allow to run makemessages inside an app dir
if os.path.isdir('locale'):
self.locale_paths.append(os.path.abspath('locale'))
if self.locale_paths:
self.default_locale_path = self.locale_paths[0]
os.makedirs(self.default_locale_path, exist_ok=True)
# Build locale list
looks_like_locale = re.compile(r'[a-z]{2}')
locale_dirs = filter(os.path.isdir, glob.glob('%s/*' % self.default_locale_path))
all_locales = [
lang_code for lang_code in map(os.path.basename, locale_dirs)
if looks_like_locale.match(lang_code)
]
# Account for excluded locales
if process_all:
locales = all_locales
else:
locales = locale or all_locales
locales = set(locales).difference(exclude)
if locales:
check_programs('msguniq', 'msgmerge', 'msgattrib')
check_programs('xgettext')
try:
potfiles = self.build_potfiles()
# Build po files for each selected locale
for locale in locales:
if self.verbosity > 0:
self.stdout.write('processing locale %s' % locale)
for potfile in potfiles:
self.write_po_file(potfile, locale)
finally:
if not self.keep_pot:
self.remove_potfiles()
@cached_property
def gettext_version(self):
# Gettext tools will output system-encoded bytestrings instead of UTF-8,
# when looking up the version. It's especially a problem on Windows.
out, err, status = popen_wrapper(
['xgettext', '--version'],
stdout_encoding=DEFAULT_LOCALE_ENCODING,
)
m = re.search(r'(\d+)\.(\d+)\.?(\d+)?', out)
if m:
return tuple(int(d) for d in m.groups() if d is not None)
else:
raise CommandError("Unable to get gettext version. Is it installed?")
@cached_property
def settings_available(self):
try:
settings.LOCALE_PATHS
except ImproperlyConfigured:
if self.verbosity > 1:
self.stderr.write("Running without configured settings.")
return False
return True
def build_potfiles(self):
"""
Build pot files and apply msguniq to them.
"""
file_list = self.find_files(".")
self.remove_potfiles()
self.process_files(file_list)
potfiles = []
for path in self.locale_paths:
potfile = os.path.join(path, '%s.pot' % self.domain)
if not os.path.exists(potfile):
continue
args = ['msguniq'] + self.msguniq_options + [potfile]
msgs, errors, status = popen_wrapper(args)
if errors:
if status != STATUS_OK:
raise CommandError(
"errors happened while running msguniq\n%s" % errors)
elif self.verbosity > 0:
self.stdout.write(errors)
msgs = normalize_eols(msgs)
with open(potfile, 'w', encoding='utf-8') as fp:
fp.write(msgs)
potfiles.append(potfile)
return potfiles
def remove_potfiles(self):
for path in self.locale_paths:
pot_path = os.path.join(path, '%s.pot' % self.domain)
if os.path.exists(pot_path):
os.unlink(pot_path)
def find_files(self, root):
"""
Get all files in the given root. Also check that there is a matching
locale dir for each file.
"""
all_files = []
ignored_roots = []
if self.settings_available:
ignored_roots = [os.path.normpath(p) for p in (settings.MEDIA_ROOT, settings.STATIC_ROOT) if p]
for dirpath, dirnames, filenames in os.walk(root, topdown=True, followlinks=self.symlinks):
for dirname in dirnames[:]:
if (is_ignored_path(os.path.normpath(os.path.join(dirpath, dirname)), self.ignore_patterns) or
os.path.join(os.path.abspath(dirpath), dirname) in ignored_roots):
dirnames.remove(dirname)
if self.verbosity > 1:
self.stdout.write('ignoring directory %s' % dirname)
elif dirname == 'locale':
dirnames.remove(dirname)
self.locale_paths.insert(0, os.path.join(os.path.abspath(dirpath), dirname))
for filename in filenames:
file_path = os.path.normpath(os.path.join(dirpath, filename))
file_ext = os.path.splitext(filename)[1]
if file_ext not in self.extensions or is_ignored_path(file_path, self.ignore_patterns):
if self.verbosity > 1:
self.stdout.write('ignoring file %s in %s' % (filename, dirpath))
else:
locale_dir = None
for path in self.locale_paths:
if os.path.abspath(dirpath).startswith(os.path.dirname(path)):
locale_dir = path
break
locale_dir = locale_dir or self.default_locale_path or NO_LOCALE_DIR
all_files.append(self.translatable_file_class(dirpath, filename, locale_dir))
return sorted(all_files)
def process_files(self, file_list):
"""
Group translatable files by locale directory and run pot file build
process for each group.
"""
file_groups = {}
for translatable in file_list:
file_group = file_groups.setdefault(translatable.locale_dir, [])
file_group.append(translatable)
for locale_dir, files in file_groups.items():
self.process_locale_dir(locale_dir, files)
def process_locale_dir(self, locale_dir, files):
"""
Extract translatable literals from the specified files, creating or
updating the POT file for a given locale directory.
Use the xgettext GNU gettext utility.
"""
build_files = []
for translatable in files:
if self.verbosity > 1:
self.stdout.write('processing file %s in %s' % (
translatable.file, translatable.dirpath
))
if self.domain not in ('djangojs', 'django'):
continue
build_file = self.build_file_class(self, self.domain, translatable)
try:
build_file.preprocess()
except UnicodeDecodeError as e:
self.stdout.write(
'UnicodeDecodeError: skipped file %s in %s (reason: %s)' % (
translatable.file, translatable.dirpath, e,
)
)
continue
build_files.append(build_file)
if self.domain == 'djangojs':
is_templatized = build_file.is_templatized
args = [
'xgettext',
'-d', self.domain,
'--language=%s' % ('C' if is_templatized else 'JavaScript',),
'--keyword=gettext_noop',
'--keyword=gettext_lazy',
'--keyword=ngettext_lazy:1,2',
'--keyword=pgettext:1c,2',
'--keyword=npgettext:1c,2,3',
'--output=-',
]
elif self.domain == 'django':
args = [
'xgettext',
'-d', self.domain,
'--language=Python',
'--keyword=gettext_noop',
'--keyword=gettext_lazy',
'--keyword=ngettext_lazy:1,2',
'--keyword=ugettext_noop',
'--keyword=ugettext_lazy',
'--keyword=ungettext_lazy:1,2',
'--keyword=pgettext:1c,2',
'--keyword=npgettext:1c,2,3',
'--keyword=pgettext_lazy:1c,2',
'--keyword=npgettext_lazy:1c,2,3',
'--output=-',
]
else:
return
input_files = [bf.work_path for bf in build_files]
with NamedTemporaryFile(mode='w+') as input_files_list:
input_files_list.write('\n'.join(input_files))
input_files_list.flush()
args.extend(['--files-from', input_files_list.name])
args.extend(self.xgettext_options)
msgs, errors, status = popen_wrapper(args)
if errors:
if status != STATUS_OK:
for build_file in build_files:
build_file.cleanup()
raise CommandError(
'errors happened while running xgettext on %s\n%s' %
('\n'.join(input_files), errors)
)
elif self.verbosity > 0:
# Print warnings
self.stdout.write(errors)
if msgs:
if locale_dir is NO_LOCALE_DIR:
file_path = os.path.normpath(build_files[0].path)
raise CommandError(
'Unable to find a locale path to store translations for '
'file %s' % file_path
)
for build_file in build_files:
msgs = build_file.postprocess_messages(msgs)
potfile = os.path.join(locale_dir, '%s.pot' % self.domain)
write_pot_file(potfile, msgs)
for build_file in build_files:
build_file.cleanup()
def write_po_file(self, potfile, locale):
"""
Create or update the PO file for self.domain and `locale`.
Use contents of the existing `potfile`.
Use msgmerge and msgattrib GNU gettext utilities.
"""
basedir = os.path.join(os.path.dirname(potfile), locale, 'LC_MESSAGES')
os.makedirs(basedir, exist_ok=True)
pofile = os.path.join(basedir, '%s.po' % self.domain)
if os.path.exists(pofile):
args = ['msgmerge'] + self.msgmerge_options + [pofile, potfile]
msgs, errors, status = popen_wrapper(args)
if errors:
if status != STATUS_OK:
raise CommandError(
"errors happened while running msgmerge\n%s" % errors)
elif self.verbosity > 0:
self.stdout.write(errors)
else:
with open(potfile, encoding='utf-8') as fp:
msgs = fp.read()
if not self.invoked_for_django:
msgs = self.copy_plural_forms(msgs, locale)
msgs = normalize_eols(msgs)
msgs = msgs.replace(
"#. #-#-#-#-# %s.pot (PACKAGE VERSION) #-#-#-#-#\n" % self.domain, "")
with open(pofile, 'w', encoding='utf-8') as fp:
fp.write(msgs)
if self.no_obsolete:
args = ['msgattrib'] + self.msgattrib_options + ['-o', pofile, pofile]
msgs, errors, status = popen_wrapper(args)
if errors:
if status != STATUS_OK:
raise CommandError(
"errors happened while running msgattrib\n%s" % errors)
elif self.verbosity > 0:
self.stdout.write(errors)
def copy_plural_forms(self, msgs, locale):
"""
Copy plural forms header contents from a Django catalog of locale to
the msgs string, inserting it at the right place. msgs should be the
contents of a newly created .po file.
"""
django_dir = os.path.normpath(os.path.join(os.path.dirname(django.__file__)))
if self.domain == 'djangojs':
domains = ('djangojs', 'django')
else:
domains = ('django',)
for domain in domains:
django_po = os.path.join(django_dir, 'conf', 'locale', locale, 'LC_MESSAGES', '%s.po' % domain)
if os.path.exists(django_po):
with open(django_po, encoding='utf-8') as fp:
m = plural_forms_re.search(fp.read())
if m:
plural_form_line = m.group('value')
if self.verbosity > 1:
self.stdout.write('copying plural forms: %s' % plural_form_line)
lines = []
found = False
for line in msgs.splitlines():
if not found and (not line or plural_forms_re.search(line)):
line = plural_form_line
found = True
lines.append(line)
msgs = '\n'.join(lines)
break
return msgs
|
892685d773a83b98d2796e262bef1696751a62491bd90d6624eff87513e81cf7 | from django.apps import apps
from django.core.management.base import BaseCommand, CommandError
from django.db import DEFAULT_DB_ALIAS, connections
from django.db.migrations.loader import AmbiguityError, MigrationLoader
class Command(BaseCommand):
help = "Prints the SQL statements for the named migration."
output_transaction = True
def add_arguments(self, parser):
parser.add_argument('app_label', help='App label of the application containing the migration.')
parser.add_argument('migration_name', help='Migration name to print the SQL for.')
parser.add_argument(
'--database', default=DEFAULT_DB_ALIAS,
help='Nominates a database to create SQL for. Defaults to the "default" database.',
)
parser.add_argument(
'--backwards', action='store_true',
help='Creates SQL to unapply the migration, rather than to apply it',
)
def execute(self, *args, **options):
# sqlmigrate doesn't support coloring its output but we need to force
# no_color=True so that the BEGIN/COMMIT statements added by
# output_transaction don't get colored either.
options['no_color'] = True
return super().execute(*args, **options)
def handle(self, *args, **options):
# Get the database we're operating from
connection = connections[options['database']]
# Load up an loader to get all the migration data, but don't replace
# migrations.
loader = MigrationLoader(connection, replace_migrations=False)
# Resolve command-line arguments into a migration
app_label, migration_name = options['app_label'], options['migration_name']
# Validate app_label
try:
apps.get_app_config(app_label)
except LookupError as err:
raise CommandError(str(err))
if app_label not in loader.migrated_apps:
raise CommandError("App '%s' does not have migrations" % app_label)
try:
migration = loader.get_migration_by_prefix(app_label, migration_name)
except AmbiguityError:
raise CommandError("More than one migration matches '%s' in app '%s'. Please be more specific." % (
migration_name, app_label))
except KeyError:
raise CommandError("Cannot find a migration matching '%s' from app '%s'. Is it in INSTALLED_APPS?" % (
migration_name, app_label))
target = (app_label, migration.name)
# Show begin/end around output for atomic migrations, if the database
# supports transactional DDL.
self.output_transaction = migration.atomic and connection.features.can_rollback_ddl
# Make a plan that represents just the requested migrations and show SQL
# for it
plan = [(loader.graph.nodes[target], options['backwards'])]
sql_statements = loader.collect_sql(plan)
if not sql_statements and options['verbosity'] >= 1:
self.stderr.write('No operations found.')
return '\n'.join(sql_statements)
|
fb6264c20337fcfe3f3386490b9eed8ecc2f4985178ab9bde29889633211a69e | import keyword
import re
from django.core.management.base import BaseCommand, CommandError
from django.db import DEFAULT_DB_ALIAS, connections
from django.db.models.constants import LOOKUP_SEP
class Command(BaseCommand):
help = "Introspects the database tables in the given database and outputs a Django model module."
requires_system_checks = False
stealth_options = ('table_name_filter',)
db_module = 'django.db'
def add_arguments(self, parser):
parser.add_argument(
'table', nargs='*', type=str,
help='Selects what tables or views should be introspected.',
)
parser.add_argument(
'--database', default=DEFAULT_DB_ALIAS,
help='Nominates a database to introspect. Defaults to using the "default" database.',
)
parser.add_argument(
'--include-partitions', action='store_true', help='Also output models for partition tables.',
)
parser.add_argument(
'--include-views', action='store_true', help='Also output models for database views.',
)
def handle(self, **options):
try:
for line in self.handle_inspection(options):
self.stdout.write(line)
except NotImplementedError:
raise CommandError("Database inspection isn't supported for the currently selected database backend.")
def handle_inspection(self, options):
connection = connections[options['database']]
# 'table_name_filter' is a stealth option
table_name_filter = options.get('table_name_filter')
def table2model(table_name):
return re.sub(r'[^a-zA-Z0-9]', '', table_name.title())
with connection.cursor() as cursor:
yield "# This is an auto-generated Django model module."
yield "# You'll have to do the following manually to clean this up:"
yield "# * Rearrange models' order"
yield "# * Make sure each model has one field with primary_key=True"
yield "# * Make sure each ForeignKey and OneToOneField has `on_delete` set to the desired behavior"
yield (
"# * Remove `managed = False` lines if you wish to allow "
"Django to create, modify, and delete the table"
)
yield "# Feel free to rename the models, but don't rename db_table values or field names."
yield 'from %s import models' % self.db_module
known_models = []
table_info = connection.introspection.get_table_list(cursor)
# Determine types of tables and/or views to be introspected.
types = {'t'}
if options['include_partitions']:
types.add('p')
if options['include_views']:
types.add('v')
for table_name in (options['table'] or sorted(info.name for info in table_info if info.type in types)):
if table_name_filter is not None and callable(table_name_filter):
if not table_name_filter(table_name):
continue
try:
try:
relations = connection.introspection.get_relations(cursor, table_name)
except NotImplementedError:
relations = {}
try:
constraints = connection.introspection.get_constraints(cursor, table_name)
except NotImplementedError:
constraints = {}
primary_key_column = connection.introspection.get_primary_key_column(cursor, table_name)
unique_columns = [
c['columns'][0] for c in constraints.values()
if c['unique'] and len(c['columns']) == 1
]
table_description = connection.introspection.get_table_description(cursor, table_name)
except Exception as e:
yield "# Unable to inspect table '%s'" % table_name
yield "# The error was: %s" % e
continue
yield ''
yield ''
yield 'class %s(models.Model):' % table2model(table_name)
known_models.append(table2model(table_name))
used_column_names = [] # Holds column names used in the table so far
column_to_field_name = {} # Maps column names to names of model fields
for row in table_description:
comment_notes = [] # Holds Field notes, to be displayed in a Python comment.
extra_params = {} # Holds Field parameters such as 'db_column'.
column_name = row.name
is_relation = column_name in relations
att_name, params, notes = self.normalize_col_name(
column_name, used_column_names, is_relation)
extra_params.update(params)
comment_notes.extend(notes)
used_column_names.append(att_name)
column_to_field_name[column_name] = att_name
# Add primary_key and unique, if necessary.
if column_name == primary_key_column:
extra_params['primary_key'] = True
elif column_name in unique_columns:
extra_params['unique'] = True
if is_relation:
if extra_params.pop('unique', False) or extra_params.get('primary_key'):
rel_type = 'OneToOneField'
else:
rel_type = 'ForeignKey'
rel_to = (
"self" if relations[column_name][1] == table_name
else table2model(relations[column_name][1])
)
if rel_to in known_models:
field_type = '%s(%s' % (rel_type, rel_to)
else:
field_type = "%s('%s'" % (rel_type, rel_to)
else:
# Calling `get_field_type` to get the field type string and any
# additional parameters and notes.
field_type, field_params, field_notes = self.get_field_type(connection, table_name, row)
extra_params.update(field_params)
comment_notes.extend(field_notes)
field_type += '('
# Don't output 'id = meta.AutoField(primary_key=True)', because
# that's assumed if it doesn't exist.
if att_name == 'id' and extra_params == {'primary_key': True}:
if field_type == 'AutoField(':
continue
elif field_type == 'IntegerField(' and not connection.features.can_introspect_autofield:
comment_notes.append('AutoField?')
# Add 'null' and 'blank', if the 'null_ok' flag was present in the
# table description.
if row.null_ok: # If it's NULL...
extra_params['blank'] = True
extra_params['null'] = True
field_desc = '%s = %s%s' % (
att_name,
# Custom fields will have a dotted path
'' if '.' in field_type else 'models.',
field_type,
)
if field_type.startswith(('ForeignKey(', 'OneToOneField(')):
field_desc += ', models.DO_NOTHING'
if extra_params:
if not field_desc.endswith('('):
field_desc += ', '
field_desc += ', '.join('%s=%r' % (k, v) for k, v in extra_params.items())
field_desc += ')'
if comment_notes:
field_desc += ' # ' + ' '.join(comment_notes)
yield ' %s' % field_desc
is_view = any(info.name == table_name and info.type == 'v' for info in table_info)
is_partition = any(info.name == table_name and info.type == 'p' for info in table_info)
yield from self.get_meta(table_name, constraints, column_to_field_name, is_view, is_partition)
def normalize_col_name(self, col_name, used_column_names, is_relation):
"""
Modify the column name to make it Python-compatible as a field name
"""
field_params = {}
field_notes = []
new_name = col_name.lower()
if new_name != col_name:
field_notes.append('Field name made lowercase.')
if is_relation:
if new_name.endswith('_id'):
new_name = new_name[:-3]
else:
field_params['db_column'] = col_name
new_name, num_repl = re.subn(r'\W', '_', new_name)
if num_repl > 0:
field_notes.append('Field renamed to remove unsuitable characters.')
if new_name.find(LOOKUP_SEP) >= 0:
while new_name.find(LOOKUP_SEP) >= 0:
new_name = new_name.replace(LOOKUP_SEP, '_')
if col_name.lower().find(LOOKUP_SEP) >= 0:
# Only add the comment if the double underscore was in the original name
field_notes.append("Field renamed because it contained more than one '_' in a row.")
if new_name.startswith('_'):
new_name = 'field%s' % new_name
field_notes.append("Field renamed because it started with '_'.")
if new_name.endswith('_'):
new_name = '%sfield' % new_name
field_notes.append("Field renamed because it ended with '_'.")
if keyword.iskeyword(new_name):
new_name += '_field'
field_notes.append('Field renamed because it was a Python reserved word.')
if new_name[0].isdigit():
new_name = 'number_%s' % new_name
field_notes.append("Field renamed because it wasn't a valid Python identifier.")
if new_name in used_column_names:
num = 0
while '%s_%d' % (new_name, num) in used_column_names:
num += 1
new_name = '%s_%d' % (new_name, num)
field_notes.append('Field renamed because of name conflict.')
if col_name != new_name and field_notes:
field_params['db_column'] = col_name
return new_name, field_params, field_notes
def get_field_type(self, connection, table_name, row):
"""
Given the database connection, the table name, and the cursor row
description, this routine will return the given field type name, as
well as any additional keyword parameters and notes for the field.
"""
field_params = {}
field_notes = []
try:
field_type = connection.introspection.get_field_type(row.type_code, row)
except KeyError:
field_type = 'TextField'
field_notes.append('This field type is a guess.')
# Add max_length for all CharFields.
if field_type == 'CharField' and row.internal_size:
field_params['max_length'] = int(row.internal_size)
if field_type == 'DecimalField':
if row.precision is None or row.scale is None:
field_notes.append(
'max_digits and decimal_places have been guessed, as this '
'database handles decimal fields as float')
field_params['max_digits'] = row.precision if row.precision is not None else 10
field_params['decimal_places'] = row.scale if row.scale is not None else 5
else:
field_params['max_digits'] = row.precision
field_params['decimal_places'] = row.scale
return field_type, field_params, field_notes
def get_meta(self, table_name, constraints, column_to_field_name, is_view, is_partition):
"""
Return a sequence comprising the lines of code necessary
to construct the inner Meta class for the model corresponding
to the given database table name.
"""
unique_together = []
has_unsupported_constraint = False
for params in constraints.values():
if params['unique']:
columns = params['columns']
if None in columns:
has_unsupported_constraint = True
columns = [x for x in columns if x is not None]
if len(columns) > 1:
unique_together.append(str(tuple(column_to_field_name[c] for c in columns)))
if is_view:
managed_comment = " # Created from a view. Don't remove."
elif is_partition:
managed_comment = " # Created from a partition. Don't remove."
else:
managed_comment = ''
meta = ['']
if has_unsupported_constraint:
meta.append(' # A unique constraint could not be introspected.')
meta += [
' class Meta:',
' managed = False%s' % managed_comment,
' db_table = %r' % table_name
]
if unique_together:
tup = '(' + ', '.join(unique_together) + ',)'
meta += [" unique_together = %s" % tup]
return meta
|
7bd9cc7f7d870ea5b6f339bf8764c43d052e0dd585b3941b86dcdef28c6f6eec | import os
import sys
from itertools import takewhile
from django.apps import apps
from django.conf import settings
from django.core.management.base import (
BaseCommand, CommandError, no_translations,
)
from django.db import DEFAULT_DB_ALIAS, connections, router
from django.db.migrations import Migration
from django.db.migrations.autodetector import MigrationAutodetector
from django.db.migrations.loader import MigrationLoader
from django.db.migrations.questioner import (
InteractiveMigrationQuestioner, MigrationQuestioner,
NonInteractiveMigrationQuestioner,
)
from django.db.migrations.state import ProjectState
from django.db.migrations.utils import get_migration_name_timestamp
from django.db.migrations.writer import MigrationWriter
class Command(BaseCommand):
help = "Creates new migration(s) for apps."
def add_arguments(self, parser):
parser.add_argument(
'args', metavar='app_label', nargs='*',
help='Specify the app label(s) to create migrations for.',
)
parser.add_argument(
'--dry-run', action='store_true',
help="Just show what migrations would be made; don't actually write them.",
)
parser.add_argument(
'--merge', action='store_true',
help="Enable fixing of migration conflicts.",
)
parser.add_argument(
'--empty', action='store_true',
help="Create an empty migration.",
)
parser.add_argument(
'--noinput', '--no-input', action='store_false', dest='interactive',
help='Tells Django to NOT prompt the user for input of any kind.',
)
parser.add_argument(
'-n', '--name',
help="Use this name for migration file(s).",
)
parser.add_argument(
'--no-header', action='store_false', dest='include_header',
help='Do not add header comments to new migration file(s).',
)
parser.add_argument(
'--check', action='store_true', dest='check_changes',
help='Exit with a non-zero status if model changes are missing migrations.',
)
@no_translations
def handle(self, *app_labels, **options):
self.verbosity = options['verbosity']
self.interactive = options['interactive']
self.dry_run = options['dry_run']
self.merge = options['merge']
self.empty = options['empty']
self.migration_name = options['name']
if self.migration_name and not self.migration_name.isidentifier():
raise CommandError('The migration name must be a valid Python identifier.')
self.include_header = options['include_header']
check_changes = options['check_changes']
# Make sure the app they asked for exists
app_labels = set(app_labels)
has_bad_labels = False
for app_label in app_labels:
try:
apps.get_app_config(app_label)
except LookupError as err:
self.stderr.write(str(err))
has_bad_labels = True
if has_bad_labels:
sys.exit(2)
# Load the current graph state. Pass in None for the connection so
# the loader doesn't try to resolve replaced migrations from DB.
loader = MigrationLoader(None, ignore_no_migrations=True)
# Raise an error if any migrations are applied before their dependencies.
consistency_check_labels = {config.label for config in apps.get_app_configs()}
# Non-default databases are only checked if database routers used.
aliases_to_check = connections if settings.DATABASE_ROUTERS else [DEFAULT_DB_ALIAS]
for alias in sorted(aliases_to_check):
connection = connections[alias]
if (connection.settings_dict['ENGINE'] != 'django.db.backends.dummy' and any(
# At least one model must be migrated to the database.
router.allow_migrate(connection.alias, app_label, model_name=model._meta.object_name)
for app_label in consistency_check_labels
for model in apps.get_app_config(app_label).get_models()
)):
loader.check_consistent_history(connection)
# Before anything else, see if there's conflicting apps and drop out
# hard if there are any and they don't want to merge
conflicts = loader.detect_conflicts()
# If app_labels is specified, filter out conflicting migrations for unspecified apps
if app_labels:
conflicts = {
app_label: conflict for app_label, conflict in conflicts.items()
if app_label in app_labels
}
if conflicts and not self.merge:
name_str = "; ".join(
"%s in %s" % (", ".join(names), app)
for app, names in conflicts.items()
)
raise CommandError(
"Conflicting migrations detected; multiple leaf nodes in the "
"migration graph: (%s).\nTo fix them run "
"'python manage.py makemigrations --merge'" % name_str
)
# If they want to merge and there's nothing to merge, then politely exit
if self.merge and not conflicts:
self.stdout.write("No conflicts detected to merge.")
return
# If they want to merge and there is something to merge, then
# divert into the merge code
if self.merge and conflicts:
return self.handle_merge(loader, conflicts)
if self.interactive:
questioner = InteractiveMigrationQuestioner(specified_apps=app_labels, dry_run=self.dry_run)
else:
questioner = NonInteractiveMigrationQuestioner(specified_apps=app_labels, dry_run=self.dry_run)
# Set up autodetector
autodetector = MigrationAutodetector(
loader.project_state(),
ProjectState.from_apps(apps),
questioner,
)
# If they want to make an empty migration, make one for each app
if self.empty:
if not app_labels:
raise CommandError("You must supply at least one app label when using --empty.")
# Make a fake changes() result we can pass to arrange_for_graph
changes = {
app: [Migration("custom", app)]
for app in app_labels
}
changes = autodetector.arrange_for_graph(
changes=changes,
graph=loader.graph,
migration_name=self.migration_name,
)
self.write_migration_files(changes)
return
# Detect changes
changes = autodetector.changes(
graph=loader.graph,
trim_to_apps=app_labels or None,
convert_apps=app_labels or None,
migration_name=self.migration_name,
)
if not changes:
# No changes? Tell them.
if self.verbosity >= 1:
if app_labels:
if len(app_labels) == 1:
self.stdout.write("No changes detected in app '%s'" % app_labels.pop())
else:
self.stdout.write("No changes detected in apps '%s'" % ("', '".join(app_labels)))
else:
self.stdout.write("No changes detected")
else:
self.write_migration_files(changes)
if check_changes:
sys.exit(1)
def write_migration_files(self, changes):
"""
Take a changes dict and write them out as migration files.
"""
directory_created = {}
for app_label, app_migrations in changes.items():
if self.verbosity >= 1:
self.stdout.write(self.style.MIGRATE_HEADING("Migrations for '%s':" % app_label))
for migration in app_migrations:
# Describe the migration
writer = MigrationWriter(migration, self.include_header)
if self.verbosity >= 1:
# Display a relative path if it's below the current working
# directory, or an absolute path otherwise.
try:
migration_string = os.path.relpath(writer.path)
except ValueError:
migration_string = writer.path
if migration_string.startswith('..'):
migration_string = writer.path
self.stdout.write(' %s\n' % self.style.MIGRATE_LABEL(migration_string))
for operation in migration.operations:
self.stdout.write(' - %s' % operation.describe())
if not self.dry_run:
# Write the migrations file to the disk.
migrations_directory = os.path.dirname(writer.path)
if not directory_created.get(app_label):
os.makedirs(migrations_directory, exist_ok=True)
init_path = os.path.join(migrations_directory, "__init__.py")
if not os.path.isfile(init_path):
open(init_path, "w").close()
# We just do this once per app
directory_created[app_label] = True
migration_string = writer.as_string()
with open(writer.path, "w", encoding='utf-8') as fh:
fh.write(migration_string)
elif self.verbosity == 3:
# Alternatively, makemigrations --dry-run --verbosity 3
# will output the migrations to stdout rather than saving
# the file to the disk.
self.stdout.write(self.style.MIGRATE_HEADING(
"Full migrations file '%s':" % writer.filename
))
self.stdout.write(writer.as_string())
def handle_merge(self, loader, conflicts):
"""
Handles merging together conflicted migrations interactively,
if it's safe; otherwise, advises on how to fix it.
"""
if self.interactive:
questioner = InteractiveMigrationQuestioner()
else:
questioner = MigrationQuestioner(defaults={'ask_merge': True})
for app_label, migration_names in conflicts.items():
# Grab out the migrations in question, and work out their
# common ancestor.
merge_migrations = []
for migration_name in migration_names:
migration = loader.get_migration(app_label, migration_name)
migration.ancestry = [
mig for mig in loader.graph.forwards_plan((app_label, migration_name))
if mig[0] == migration.app_label
]
merge_migrations.append(migration)
def all_items_equal(seq):
return all(item == seq[0] for item in seq[1:])
merge_migrations_generations = zip(*(m.ancestry for m in merge_migrations))
common_ancestor_count = sum(1 for common_ancestor_generation
in takewhile(all_items_equal, merge_migrations_generations))
if not common_ancestor_count:
raise ValueError("Could not find common ancestor of %s" % migration_names)
# Now work out the operations along each divergent branch
for migration in merge_migrations:
migration.branch = migration.ancestry[common_ancestor_count:]
migrations_ops = (loader.get_migration(node_app, node_name).operations
for node_app, node_name in migration.branch)
migration.merged_operations = sum(migrations_ops, [])
# In future, this could use some of the Optimizer code
# (can_optimize_through) to automatically see if they're
# mergeable. For now, we always just prompt the user.
if self.verbosity > 0:
self.stdout.write(self.style.MIGRATE_HEADING("Merging %s" % app_label))
for migration in merge_migrations:
self.stdout.write(self.style.MIGRATE_LABEL(" Branch %s" % migration.name))
for operation in migration.merged_operations:
self.stdout.write(' - %s' % operation.describe())
if questioner.ask_merge(app_label):
# If they still want to merge it, then write out an empty
# file depending on the migrations needing merging.
numbers = [
MigrationAutodetector.parse_number(migration.name)
for migration in merge_migrations
]
try:
biggest_number = max(x for x in numbers if x is not None)
except ValueError:
biggest_number = 1
subclass = type("Migration", (Migration,), {
"dependencies": [(app_label, migration.name) for migration in merge_migrations],
})
migration_name = "%04i_%s" % (
biggest_number + 1,
self.migration_name or ("merge_%s" % get_migration_name_timestamp())
)
new_migration = subclass(migration_name, app_label)
writer = MigrationWriter(new_migration, self.include_header)
if not self.dry_run:
# Write the merge migrations file to the disk
with open(writer.path, "w", encoding='utf-8') as fh:
fh.write(writer.as_string())
if self.verbosity > 0:
self.stdout.write("\nCreated new merge migration %s" % writer.path)
elif self.verbosity == 3:
# Alternatively, makemigrations --merge --dry-run --verbosity 3
# will output the merge migrations to stdout rather than saving
# the file to the disk.
self.stdout.write(self.style.MIGRATE_HEADING(
"Full merge migrations file '%s':" % writer.filename
))
self.stdout.write(writer.as_string())
|
8a1b6c72ce4c9db99ed5d065de95dd0d73437ba0b6581cea00df86bae8a1482c | import inspect
from importlib import import_module
from inspect import cleandoc
from pathlib import Path
from django.apps import apps
from django.conf import settings
from django.contrib import admin
from django.contrib.admin.views.decorators import staff_member_required
from django.contrib.admindocs import utils
from django.contrib.admindocs.utils import (
replace_named_groups, replace_unnamed_groups,
)
from django.core.exceptions import ImproperlyConfigured, ViewDoesNotExist
from django.db import models
from django.http import Http404
from django.template.engine import Engine
from django.urls import get_mod_func, get_resolver, get_urlconf
from django.utils.decorators import method_decorator
from django.utils.inspect import (
func_accepts_kwargs, func_accepts_var_args, get_func_full_args,
method_has_no_args,
)
from django.utils.translation import gettext as _
from django.views.generic import TemplateView
from .utils import get_view_name
# Exclude methods starting with these strings from documentation
MODEL_METHODS_EXCLUDE = ('_', 'add_', 'delete', 'save', 'set_')
class BaseAdminDocsView(TemplateView):
"""
Base view for admindocs views.
"""
@method_decorator(staff_member_required)
def dispatch(self, request, *args, **kwargs):
if not utils.docutils_is_available:
# Display an error message for people without docutils
self.template_name = 'admin_doc/missing_docutils.html'
return self.render_to_response(admin.site.each_context(request))
return super().dispatch(request, *args, **kwargs)
def get_context_data(self, **kwargs):
return super().get_context_data(**{
**kwargs,
**admin.site.each_context(self.request),
})
class BookmarkletsView(BaseAdminDocsView):
template_name = 'admin_doc/bookmarklets.html'
class TemplateTagIndexView(BaseAdminDocsView):
template_name = 'admin_doc/template_tag_index.html'
def get_context_data(self, **kwargs):
tags = []
try:
engine = Engine.get_default()
except ImproperlyConfigured:
# Non-trivial TEMPLATES settings aren't supported (#24125).
pass
else:
app_libs = sorted(engine.template_libraries.items())
builtin_libs = [('', lib) for lib in engine.template_builtins]
for module_name, library in builtin_libs + app_libs:
for tag_name, tag_func in library.tags.items():
title, body, metadata = utils.parse_docstring(tag_func.__doc__)
title = title and utils.parse_rst(title, 'tag', _('tag:') + tag_name)
body = body and utils.parse_rst(body, 'tag', _('tag:') + tag_name)
for key in metadata:
metadata[key] = utils.parse_rst(metadata[key], 'tag', _('tag:') + tag_name)
tag_library = module_name.split('.')[-1]
tags.append({
'name': tag_name,
'title': title,
'body': body,
'meta': metadata,
'library': tag_library,
})
return super().get_context_data(**{**kwargs, 'tags': tags})
class TemplateFilterIndexView(BaseAdminDocsView):
template_name = 'admin_doc/template_filter_index.html'
def get_context_data(self, **kwargs):
filters = []
try:
engine = Engine.get_default()
except ImproperlyConfigured:
# Non-trivial TEMPLATES settings aren't supported (#24125).
pass
else:
app_libs = sorted(engine.template_libraries.items())
builtin_libs = [('', lib) for lib in engine.template_builtins]
for module_name, library in builtin_libs + app_libs:
for filter_name, filter_func in library.filters.items():
title, body, metadata = utils.parse_docstring(filter_func.__doc__)
title = title and utils.parse_rst(title, 'filter', _('filter:') + filter_name)
body = body and utils.parse_rst(body, 'filter', _('filter:') + filter_name)
for key in metadata:
metadata[key] = utils.parse_rst(metadata[key], 'filter', _('filter:') + filter_name)
tag_library = module_name.split('.')[-1]
filters.append({
'name': filter_name,
'title': title,
'body': body,
'meta': metadata,
'library': tag_library,
})
return super().get_context_data(**{**kwargs, 'filters': filters})
class ViewIndexView(BaseAdminDocsView):
template_name = 'admin_doc/view_index.html'
def get_context_data(self, **kwargs):
views = []
urlconf = import_module(settings.ROOT_URLCONF)
view_functions = extract_views_from_urlpatterns(urlconf.urlpatterns)
for (func, regex, namespace, name) in view_functions:
views.append({
'full_name': get_view_name(func),
'url': simplify_regex(regex),
'url_name': ':'.join((namespace or []) + (name and [name] or [])),
'namespace': ':'.join(namespace or []),
'name': name,
})
return super().get_context_data(**{**kwargs, 'views': views})
class ViewDetailView(BaseAdminDocsView):
template_name = 'admin_doc/view_detail.html'
@staticmethod
def _get_view_func(view):
urlconf = get_urlconf()
if get_resolver(urlconf)._is_callback(view):
mod, func = get_mod_func(view)
try:
# Separate the module and function, e.g.
# 'mymodule.views.myview' -> 'mymodule.views', 'myview').
return getattr(import_module(mod), func)
except ImportError:
# Import may fail because view contains a class name, e.g.
# 'mymodule.views.ViewContainer.my_view', so mod takes the form
# 'mymodule.views.ViewContainer'. Parse it again to separate
# the module and class.
mod, klass = get_mod_func(mod)
return getattr(getattr(import_module(mod), klass), func)
def get_context_data(self, **kwargs):
view = self.kwargs['view']
view_func = self._get_view_func(view)
if view_func is None:
raise Http404
title, body, metadata = utils.parse_docstring(view_func.__doc__)
title = title and utils.parse_rst(title, 'view', _('view:') + view)
body = body and utils.parse_rst(body, 'view', _('view:') + view)
for key in metadata:
metadata[key] = utils.parse_rst(metadata[key], 'model', _('view:') + view)
return super().get_context_data(**{
**kwargs,
'name': view,
'summary': title,
'body': body,
'meta': metadata,
})
class ModelIndexView(BaseAdminDocsView):
template_name = 'admin_doc/model_index.html'
def get_context_data(self, **kwargs):
m_list = [m._meta for m in apps.get_models()]
return super().get_context_data(**{**kwargs, 'models': m_list})
class ModelDetailView(BaseAdminDocsView):
template_name = 'admin_doc/model_detail.html'
def get_context_data(self, **kwargs):
model_name = self.kwargs['model_name']
# Get the model class.
try:
app_config = apps.get_app_config(self.kwargs['app_label'])
except LookupError:
raise Http404(_("App %(app_label)r not found") % self.kwargs)
try:
model = app_config.get_model(model_name)
except LookupError:
raise Http404(_("Model %(model_name)r not found in app %(app_label)r") % self.kwargs)
opts = model._meta
title, body, metadata = utils.parse_docstring(model.__doc__)
title = title and utils.parse_rst(title, 'model', _('model:') + model_name)
body = body and utils.parse_rst(body, 'model', _('model:') + model_name)
# Gather fields/field descriptions.
fields = []
for field in opts.fields:
# ForeignKey is a special case since the field will actually be a
# descriptor that returns the other object
if isinstance(field, models.ForeignKey):
data_type = field.remote_field.model.__name__
app_label = field.remote_field.model._meta.app_label
verbose = utils.parse_rst(
(_("the related `%(app_label)s.%(data_type)s` object") % {
'app_label': app_label, 'data_type': data_type,
}),
'model',
_('model:') + data_type,
)
else:
data_type = get_readable_field_data_type(field)
verbose = field.verbose_name
fields.append({
'name': field.name,
'data_type': data_type,
'verbose': verbose or '',
'help_text': field.help_text,
})
# Gather many-to-many fields.
for field in opts.many_to_many:
data_type = field.remote_field.model.__name__
app_label = field.remote_field.model._meta.app_label
verbose = _("related `%(app_label)s.%(object_name)s` objects") % {
'app_label': app_label,
'object_name': data_type,
}
fields.append({
'name': "%s.all" % field.name,
"data_type": 'List',
'verbose': utils.parse_rst(_("all %s") % verbose, 'model', _('model:') + opts.model_name),
})
fields.append({
'name': "%s.count" % field.name,
'data_type': 'Integer',
'verbose': utils.parse_rst(_("number of %s") % verbose, 'model', _('model:') + opts.model_name),
})
methods = []
# Gather model methods.
for func_name, func in model.__dict__.items():
if inspect.isfunction(func) or isinstance(func, property):
try:
for exclude in MODEL_METHODS_EXCLUDE:
if func_name.startswith(exclude):
raise StopIteration
except StopIteration:
continue
verbose = func.__doc__
verbose = verbose and (
utils.parse_rst(cleandoc(verbose), 'model', _('model:') + opts.model_name)
)
# Show properties and methods without arguments as fields.
# Otherwise, show as a 'method with arguments'.
if isinstance(func, property):
fields.append({
'name': func_name,
'data_type': get_return_data_type(func_name),
'verbose': verbose or ''
})
elif method_has_no_args(func) and not func_accepts_kwargs(func) and not func_accepts_var_args(func):
fields.append({
'name': func_name,
'data_type': get_return_data_type(func_name),
'verbose': verbose or '',
})
else:
arguments = get_func_full_args(func)
# Join arguments with ', ' and in case of default value,
# join it with '='. Use repr() so that strings will be
# correctly displayed.
print_arguments = ', '.join([
'='.join([arg_el[0], *map(repr, arg_el[1:])])
for arg_el in arguments
])
methods.append({
'name': func_name,
'arguments': print_arguments,
'verbose': verbose or '',
})
# Gather related objects
for rel in opts.related_objects:
verbose = _("related `%(app_label)s.%(object_name)s` objects") % {
'app_label': rel.related_model._meta.app_label,
'object_name': rel.related_model._meta.object_name,
}
accessor = rel.get_accessor_name()
fields.append({
'name': "%s.all" % accessor,
'data_type': 'List',
'verbose': utils.parse_rst(_("all %s") % verbose, 'model', _('model:') + opts.model_name),
})
fields.append({
'name': "%s.count" % accessor,
'data_type': 'Integer',
'verbose': utils.parse_rst(_("number of %s") % verbose, 'model', _('model:') + opts.model_name),
})
return super().get_context_data(**{
**kwargs,
'name': opts.label,
'summary': title,
'description': body,
'fields': fields,
'methods': methods,
})
class TemplateDetailView(BaseAdminDocsView):
template_name = 'admin_doc/template_detail.html'
def get_context_data(self, **kwargs):
template = self.kwargs['template']
templates = []
try:
default_engine = Engine.get_default()
except ImproperlyConfigured:
# Non-trivial TEMPLATES settings aren't supported (#24125).
pass
else:
# This doesn't account for template loaders (#24128).
for index, directory in enumerate(default_engine.dirs):
template_file = Path(directory) / template
if template_file.exists():
template_contents = template_file.read_text()
else:
template_contents = ''
templates.append({
'file': template_file,
'exists': template_file.exists(),
'contents': template_contents,
'order': index,
})
return super().get_context_data(**{
**kwargs,
'name': template,
'templates': templates,
})
####################
# Helper functions #
####################
def get_return_data_type(func_name):
"""Return a somewhat-helpful data type given a function name"""
if func_name.startswith('get_'):
if func_name.endswith('_list'):
return 'List'
elif func_name.endswith('_count'):
return 'Integer'
return ''
def get_readable_field_data_type(field):
"""
Return the description for a given field type, if it exists. Fields'
descriptions can contain format strings, which will be interpolated with
the values of field.__dict__ before being output.
"""
return field.description % field.__dict__
def extract_views_from_urlpatterns(urlpatterns, base='', namespace=None):
"""
Return a list of views from a list of urlpatterns.
Each object in the returned list is a two-tuple: (view_func, regex)
"""
views = []
for p in urlpatterns:
if hasattr(p, 'url_patterns'):
try:
patterns = p.url_patterns
except ImportError:
continue
views.extend(extract_views_from_urlpatterns(
patterns,
base + str(p.pattern),
(namespace or []) + (p.namespace and [p.namespace] or [])
))
elif hasattr(p, 'callback'):
try:
views.append((p.callback, base + str(p.pattern), namespace, p.name))
except ViewDoesNotExist:
continue
else:
raise TypeError(_("%s does not appear to be a urlpattern object") % p)
return views
def simplify_regex(pattern):
r"""
Clean up urlpattern regexes into something more readable by humans. For
example, turn "^(?P<sport_slug>\w+)/athletes/(?P<athlete_slug>\w+)/$"
into "/<sport_slug>/athletes/<athlete_slug>/".
"""
pattern = replace_named_groups(pattern)
pattern = replace_unnamed_groups(pattern)
# clean up any outstanding regex-y characters.
pattern = pattern.replace('^', '').replace('$', '').replace('?', '')
if not pattern.startswith('/'):
pattern = '/' + pattern
return pattern
|
927756a4c6c9874a0c01ac4a9e4bfc27b4a1911498e00266c6ab448205020a96 | from django.db import NotSupportedError
from django.db.models import Index
from django.utils.functional import cached_property
__all__ = [
'BloomIndex', 'BrinIndex', 'BTreeIndex', 'GinIndex', 'GistIndex',
'HashIndex', 'SpGistIndex',
]
class PostgresIndex(Index):
@cached_property
def max_name_length(self):
# Allow an index name longer than 30 characters when the suffix is
# longer than the usual 3 character limit. The 30 character limit for
# cross-database compatibility isn't applicable to PostgreSQL-specific
# indexes.
return Index.max_name_length - len(Index.suffix) + len(self.suffix)
def create_sql(self, model, schema_editor, using='', **kwargs):
self.check_supported(schema_editor)
statement = super().create_sql(model, schema_editor, using=' USING %s' % self.suffix, **kwargs)
with_params = self.get_with_params()
if with_params:
statement.parts['extra'] = 'WITH (%s) %s' % (
', '.join(with_params),
statement.parts['extra'],
)
return statement
def check_supported(self, schema_editor):
pass
def get_with_params(self):
return []
class BloomIndex(PostgresIndex):
suffix = 'bloom'
def __init__(self, *, length=None, columns=(), **kwargs):
super().__init__(**kwargs)
if len(self.fields) > 32:
raise ValueError('Bloom indexes support a maximum of 32 fields.')
if not isinstance(columns, (list, tuple)):
raise ValueError('BloomIndex.columns must be a list or tuple.')
if len(columns) > len(self.fields):
raise ValueError(
'BloomIndex.columns cannot have more values than fields.'
)
if not all(0 < col <= 4095 for col in columns):
raise ValueError(
'BloomIndex.columns must contain integers from 1 to 4095.',
)
if length is not None and not 0 < length <= 4096:
raise ValueError(
'BloomIndex.length must be None or an integer from 1 to 4096.',
)
self.length = length
self.columns = columns
def deconstruct(self):
path, args, kwargs = super().deconstruct()
if self.length is not None:
kwargs['length'] = self.length
if self.columns:
kwargs['columns'] = self.columns
return path, args, kwargs
def check_supported(self, schema_editor):
if not schema_editor.connection.features.has_bloom_index:
raise NotSupportedError('Bloom indexes require PostgreSQL 9.6+.')
def get_with_params(self):
with_params = []
if self.length is not None:
with_params.append('length = %d' % self.length)
if self.columns:
with_params.extend(
'col%d = %d' % (i, v)
for i, v in enumerate(self.columns, start=1)
)
return with_params
class BrinIndex(PostgresIndex):
suffix = 'brin'
def __init__(self, *, autosummarize=None, pages_per_range=None, **kwargs):
if pages_per_range is not None and pages_per_range <= 0:
raise ValueError('pages_per_range must be None or a positive integer')
self.autosummarize = autosummarize
self.pages_per_range = pages_per_range
super().__init__(**kwargs)
def deconstruct(self):
path, args, kwargs = super().deconstruct()
if self.autosummarize is not None:
kwargs['autosummarize'] = self.autosummarize
if self.pages_per_range is not None:
kwargs['pages_per_range'] = self.pages_per_range
return path, args, kwargs
def check_supported(self, schema_editor):
if self.autosummarize and not schema_editor.connection.features.has_brin_autosummarize:
raise NotSupportedError('BRIN option autosummarize requires PostgreSQL 10+.')
def get_with_params(self):
with_params = []
if self.autosummarize is not None:
with_params.append('autosummarize = %s' % ('on' if self.autosummarize else 'off'))
if self.pages_per_range is not None:
with_params.append('pages_per_range = %d' % self.pages_per_range)
return with_params
class BTreeIndex(PostgresIndex):
suffix = 'btree'
def __init__(self, *, fillfactor=None, **kwargs):
self.fillfactor = fillfactor
super().__init__(**kwargs)
def deconstruct(self):
path, args, kwargs = super().deconstruct()
if self.fillfactor is not None:
kwargs['fillfactor'] = self.fillfactor
return path, args, kwargs
def get_with_params(self):
with_params = []
if self.fillfactor is not None:
with_params.append('fillfactor = %d' % self.fillfactor)
return with_params
class GinIndex(PostgresIndex):
suffix = 'gin'
def __init__(self, *, fastupdate=None, gin_pending_list_limit=None, **kwargs):
self.fastupdate = fastupdate
self.gin_pending_list_limit = gin_pending_list_limit
super().__init__(**kwargs)
def deconstruct(self):
path, args, kwargs = super().deconstruct()
if self.fastupdate is not None:
kwargs['fastupdate'] = self.fastupdate
if self.gin_pending_list_limit is not None:
kwargs['gin_pending_list_limit'] = self.gin_pending_list_limit
return path, args, kwargs
def get_with_params(self):
with_params = []
if self.gin_pending_list_limit is not None:
with_params.append('gin_pending_list_limit = %d' % self.gin_pending_list_limit)
if self.fastupdate is not None:
with_params.append('fastupdate = %s' % ('on' if self.fastupdate else 'off'))
return with_params
class GistIndex(PostgresIndex):
suffix = 'gist'
def __init__(self, *, buffering=None, fillfactor=None, **kwargs):
self.buffering = buffering
self.fillfactor = fillfactor
super().__init__(**kwargs)
def deconstruct(self):
path, args, kwargs = super().deconstruct()
if self.buffering is not None:
kwargs['buffering'] = self.buffering
if self.fillfactor is not None:
kwargs['fillfactor'] = self.fillfactor
return path, args, kwargs
def get_with_params(self):
with_params = []
if self.buffering is not None:
with_params.append('buffering = %s' % ('on' if self.buffering else 'off'))
if self.fillfactor is not None:
with_params.append('fillfactor = %d' % self.fillfactor)
return with_params
class HashIndex(PostgresIndex):
suffix = 'hash'
def __init__(self, *, fillfactor=None, **kwargs):
self.fillfactor = fillfactor
super().__init__(**kwargs)
def deconstruct(self):
path, args, kwargs = super().deconstruct()
if self.fillfactor is not None:
kwargs['fillfactor'] = self.fillfactor
return path, args, kwargs
def get_with_params(self):
with_params = []
if self.fillfactor is not None:
with_params.append('fillfactor = %d' % self.fillfactor)
return with_params
class SpGistIndex(PostgresIndex):
suffix = 'spgist'
def __init__(self, *, fillfactor=None, **kwargs):
self.fillfactor = fillfactor
super().__init__(**kwargs)
def deconstruct(self):
path, args, kwargs = super().deconstruct()
if self.fillfactor is not None:
kwargs['fillfactor'] = self.fillfactor
return path, args, kwargs
def get_with_params(self):
with_params = []
if self.fillfactor is not None:
with_params.append('fillfactor = %d' % self.fillfactor)
return with_params
|
f0cb5453adbbf11a2fd6a40bb9b65a9f1dced43293ed184a46b9b86d64ba9dfd | import psycopg2
from django.db.models import (
CharField, Expression, Field, FloatField, Func, Lookup, TextField, Value,
)
from django.db.models.expressions import CombinedExpression
from django.db.models.functions import Cast, Coalesce
class SearchVectorExact(Lookup):
lookup_name = 'exact'
def process_rhs(self, qn, connection):
if not isinstance(self.rhs, (SearchQuery, CombinedSearchQuery)):
config = getattr(self.lhs, 'config', None)
self.rhs = SearchQuery(self.rhs, config=config)
rhs, rhs_params = super().process_rhs(qn, connection)
return rhs, rhs_params
def as_sql(self, qn, connection):
lhs, lhs_params = self.process_lhs(qn, connection)
rhs, rhs_params = self.process_rhs(qn, connection)
params = lhs_params + rhs_params
return '%s @@ %s' % (lhs, rhs), params
class SearchVectorField(Field):
def db_type(self, connection):
return 'tsvector'
class SearchQueryField(Field):
def db_type(self, connection):
return 'tsquery'
class SearchConfig(Expression):
def __init__(self, config):
super().__init__()
if not hasattr(config, 'resolve_expression'):
config = Value(config)
self.config = config
@classmethod
def from_parameter(cls, config):
if config is None or isinstance(config, cls):
return config
return cls(config)
def get_source_expressions(self):
return [self.config]
def set_source_expressions(self, exprs):
self.config, = exprs
def as_sql(self, compiler, connection):
sql, params = compiler.compile(self.config)
return '%s::regconfig' % sql, params
class SearchVectorCombinable:
ADD = '||'
def _combine(self, other, connector, reversed):
if not isinstance(other, SearchVectorCombinable):
raise TypeError(
'SearchVector can only be combined with other SearchVector '
'instances, got %s.' % type(other).__name__
)
if reversed:
return CombinedSearchVector(other, connector, self, self.config)
return CombinedSearchVector(self, connector, other, self.config)
class SearchVector(SearchVectorCombinable, Func):
function = 'to_tsvector'
arg_joiner = " || ' ' || "
output_field = SearchVectorField()
def __init__(self, *expressions, config=None, weight=None):
super().__init__(*expressions)
self.config = SearchConfig.from_parameter(config)
if weight is not None and not hasattr(weight, 'resolve_expression'):
weight = Value(weight)
self.weight = weight
def resolve_expression(self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False):
resolved = super().resolve_expression(query, allow_joins, reuse, summarize, for_save)
if self.config:
resolved.config = self.config.resolve_expression(query, allow_joins, reuse, summarize, for_save)
return resolved
def as_sql(self, compiler, connection, function=None, template=None):
clone = self.copy()
clone.set_source_expressions([
Coalesce(
expression
if isinstance(expression.output_field, (CharField, TextField))
else Cast(expression, TextField()),
Value('')
) for expression in clone.get_source_expressions()
])
config_sql = None
config_params = []
if template is None:
if clone.config:
config_sql, config_params = compiler.compile(clone.config)
template = '%(function)s(%(config)s, %(expressions)s)'
else:
template = clone.template
sql, params = super(SearchVector, clone).as_sql(
compiler, connection, function=function, template=template,
config=config_sql,
)
extra_params = []
if clone.weight:
weight_sql, extra_params = compiler.compile(clone.weight)
sql = 'setweight({}, {})'.format(sql, weight_sql)
return sql, config_params + params + extra_params
class CombinedSearchVector(SearchVectorCombinable, CombinedExpression):
def __init__(self, lhs, connector, rhs, config, output_field=None):
self.config = config
super().__init__(lhs, connector, rhs, output_field)
class SearchQueryCombinable:
BITAND = '&&'
BITOR = '||'
def _combine(self, other, connector, reversed):
if not isinstance(other, SearchQueryCombinable):
raise TypeError(
'SearchQuery can only be combined with other SearchQuery '
'instances, got %s.' % type(other).__name__
)
if reversed:
return CombinedSearchQuery(other, connector, self, self.config)
return CombinedSearchQuery(self, connector, other, self.config)
# On Combinable, these are not implemented to reduce confusion with Q. In
# this case we are actually (ab)using them to do logical combination so
# it's consistent with other usage in Django.
def __or__(self, other):
return self._combine(other, self.BITOR, False)
def __ror__(self, other):
return self._combine(other, self.BITOR, True)
def __and__(self, other):
return self._combine(other, self.BITAND, False)
def __rand__(self, other):
return self._combine(other, self.BITAND, True)
class SearchQuery(SearchQueryCombinable, Func):
output_field = SearchQueryField()
SEARCH_TYPES = {
'plain': 'plainto_tsquery',
'phrase': 'phraseto_tsquery',
'raw': 'to_tsquery',
'websearch': 'websearch_to_tsquery',
}
def __init__(self, value, output_field=None, *, config=None, invert=False, search_type='plain'):
self.function = self.SEARCH_TYPES.get(search_type)
if self.function is None:
raise ValueError("Unknown search_type argument '%s'." % search_type)
if not hasattr(value, 'resolve_expression'):
value = Value(value)
expressions = (value,)
self.config = SearchConfig.from_parameter(config)
if self.config is not None:
expressions = (self.config,) + expressions
self.invert = invert
super().__init__(*expressions, output_field=output_field)
def as_sql(self, compiler, connection, function=None, template=None):
sql, params = super().as_sql(compiler, connection, function, template)
if self.invert:
sql = '!!(%s)' % sql
return sql, params
def __invert__(self):
clone = self.copy()
clone.invert = not self.invert
return clone
def __str__(self):
result = super().__str__()
return ('~%s' % result) if self.invert else result
class CombinedSearchQuery(SearchQueryCombinable, CombinedExpression):
def __init__(self, lhs, connector, rhs, config, output_field=None):
self.config = config
super().__init__(lhs, connector, rhs, output_field)
def __str__(self):
return '(%s)' % super().__str__()
class SearchRank(Func):
function = 'ts_rank'
output_field = FloatField()
def __init__(
self, vector, query, weights=None, normalization=None,
cover_density=False,
):
if not hasattr(vector, 'resolve_expression'):
vector = SearchVector(vector)
if not hasattr(query, 'resolve_expression'):
query = SearchQuery(query)
expressions = (vector, query)
if weights is not None:
if not hasattr(weights, 'resolve_expression'):
weights = Value(weights)
expressions = (weights,) + expressions
if normalization is not None:
if not hasattr(normalization, 'resolve_expression'):
normalization = Value(normalization)
expressions += (normalization,)
if cover_density:
self.function = 'ts_rank_cd'
super().__init__(*expressions)
class SearchHeadline(Func):
function = 'ts_headline'
template = '%(function)s(%(expressions)s%(options)s)'
output_field = TextField()
def __init__(
self, expression, query, *, config=None, start_sel=None, stop_sel=None,
max_words=None, min_words=None, short_word=None, highlight_all=None,
max_fragments=None, fragment_delimiter=None,
):
if not hasattr(query, 'resolve_expression'):
query = SearchQuery(query)
options = {
'StartSel': start_sel,
'StopSel': stop_sel,
'MaxWords': max_words,
'MinWords': min_words,
'ShortWord': short_word,
'HighlightAll': highlight_all,
'MaxFragments': max_fragments,
'FragmentDelimiter': fragment_delimiter,
}
self.options = {
option: value
for option, value in options.items() if value is not None
}
expressions = (expression, query)
if config is not None:
config = SearchConfig.from_parameter(config)
expressions = (config,) + expressions
super().__init__(*expressions)
def as_sql(self, compiler, connection, function=None, template=None):
options_sql = ''
options_params = []
if self.options:
# getquoted() returns a quoted bytestring of the adapted value.
options_params.append(', '.join(
'%s=%s' % (
option,
psycopg2.extensions.adapt(value).getquoted().decode(),
) for option, value in self.options.items()
))
options_sql = ', %s'
sql, params = super().as_sql(
compiler, connection, function=function, template=template,
options=options_sql,
)
return sql, params + options_params
SearchVectorField.register_lookup(SearchVectorExact)
class TrigramBase(Func):
output_field = FloatField()
def __init__(self, expression, string, **extra):
if not hasattr(string, 'resolve_expression'):
string = Value(string)
super().__init__(expression, string, **extra)
class TrigramSimilarity(TrigramBase):
function = 'SIMILARITY'
class TrigramDistance(TrigramBase):
function = ''
arg_joiner = ' <-> '
|
7b040bdb8fb360a3eeda1d308d4f2b26bf5ab280d281ba441257fb6f8a6a6bdd | from psycopg2.extras import (
DateRange, DateTimeRange, DateTimeTZRange, NumericRange,
)
from django.apps import AppConfig
from django.db import connections
from django.db.backends.signals import connection_created
from django.db.migrations.writer import MigrationWriter
from django.db.models import CharField, TextField
from django.test.signals import setting_changed
from django.utils.translation import gettext_lazy as _
from .lookups import SearchLookup, TrigramSimilar, Unaccent
from .serializers import RangeSerializer
from .signals import register_type_handlers
RANGE_TYPES = (DateRange, DateTimeRange, DateTimeTZRange, NumericRange)
def uninstall_if_needed(setting, value, enter, **kwargs):
"""
Undo the effects of PostgresConfig.ready() when django.contrib.postgres
is "uninstalled" by override_settings().
"""
if not enter and setting == 'INSTALLED_APPS' and 'django.contrib.postgres' not in set(value):
connection_created.disconnect(register_type_handlers)
CharField._unregister_lookup(Unaccent)
TextField._unregister_lookup(Unaccent)
CharField._unregister_lookup(SearchLookup)
TextField._unregister_lookup(SearchLookup)
CharField._unregister_lookup(TrigramSimilar)
TextField._unregister_lookup(TrigramSimilar)
# Disconnect this receiver until the next time this app is installed
# and ready() connects it again to prevent unnecessary processing on
# each setting change.
setting_changed.disconnect(uninstall_if_needed)
MigrationWriter.unregister_serializer(RANGE_TYPES)
class PostgresConfig(AppConfig):
name = 'django.contrib.postgres'
verbose_name = _('PostgreSQL extensions')
def ready(self):
setting_changed.connect(uninstall_if_needed)
# Connections may already exist before we are called.
for conn in connections.all():
if conn.vendor == 'postgresql':
conn.introspection.data_types_reverse.update({
3904: 'django.contrib.postgres.fields.IntegerRangeField',
3906: 'django.contrib.postgres.fields.DecimalRangeField',
3910: 'django.contrib.postgres.fields.DateTimeRangeField',
3912: 'django.contrib.postgres.fields.DateRangeField',
3926: 'django.contrib.postgres.fields.BigIntegerRangeField',
})
if conn.connection is not None:
register_type_handlers(conn)
connection_created.connect(register_type_handlers)
CharField.register_lookup(Unaccent)
TextField.register_lookup(Unaccent)
CharField.register_lookup(SearchLookup)
TextField.register_lookup(SearchLookup)
CharField.register_lookup(TrigramSimilar)
TextField.register_lookup(TrigramSimilar)
MigrationWriter.register_serializer(RANGE_TYPES, RangeSerializer)
|
7bb97d063faa51c685a0b97b2fef60b160ce25f80ea272dbf79286e4d7dd3cd0 | from django.contrib.postgres.signals import (
get_citext_oids, get_hstore_oids, register_type_handlers,
)
from django.db import NotSupportedError, router
from django.db.migrations import AddIndex, RemoveIndex
from django.db.migrations.operations.base import Operation
class CreateExtension(Operation):
reversible = True
def __init__(self, name):
self.name = name
def state_forwards(self, app_label, state):
pass
def database_forwards(self, app_label, schema_editor, from_state, to_state):
if (
schema_editor.connection.vendor != 'postgresql' or
not router.allow_migrate(schema_editor.connection.alias, app_label)
):
return
schema_editor.execute("CREATE EXTENSION IF NOT EXISTS %s" % schema_editor.quote_name(self.name))
# Clear cached, stale oids.
get_hstore_oids.cache_clear()
get_citext_oids.cache_clear()
# Registering new type handlers cannot be done before the extension is
# installed, otherwise a subsequent data migration would use the same
# connection.
register_type_handlers(schema_editor.connection)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
if not router.allow_migrate(schema_editor.connection.alias, app_label):
return
schema_editor.execute("DROP EXTENSION %s" % schema_editor.quote_name(self.name))
# Clear cached, stale oids.
get_hstore_oids.cache_clear()
get_citext_oids.cache_clear()
def describe(self):
return "Creates extension %s" % self.name
class BloomExtension(CreateExtension):
def __init__(self):
self.name = 'bloom'
class BtreeGinExtension(CreateExtension):
def __init__(self):
self.name = 'btree_gin'
class BtreeGistExtension(CreateExtension):
def __init__(self):
self.name = 'btree_gist'
class CITextExtension(CreateExtension):
def __init__(self):
self.name = 'citext'
class CryptoExtension(CreateExtension):
def __init__(self):
self.name = 'pgcrypto'
class HStoreExtension(CreateExtension):
def __init__(self):
self.name = 'hstore'
class TrigramExtension(CreateExtension):
def __init__(self):
self.name = 'pg_trgm'
class UnaccentExtension(CreateExtension):
def __init__(self):
self.name = 'unaccent'
class NotInTransactionMixin:
def _ensure_not_in_transaction(self, schema_editor):
if schema_editor.connection.in_atomic_block:
raise NotSupportedError(
'The %s operation cannot be executed inside a transaction '
'(set atomic = False on the migration).'
% self.__class__.__name__
)
class AddIndexConcurrently(NotInTransactionMixin, AddIndex):
"""Create an index using PostgreSQL's CREATE INDEX CONCURRENTLY syntax."""
atomic = False
def describe(self):
return 'Concurrently create index %s on field(s) %s of model %s' % (
self.index.name,
', '.join(self.index.fields),
self.model_name,
)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
self._ensure_not_in_transaction(schema_editor)
model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
schema_editor.add_index(model, self.index, concurrently=True)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
self._ensure_not_in_transaction(schema_editor)
model = from_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
schema_editor.remove_index(model, self.index, concurrently=True)
class RemoveIndexConcurrently(NotInTransactionMixin, RemoveIndex):
"""Remove an index using PostgreSQL's DROP INDEX CONCURRENTLY syntax."""
atomic = False
def describe(self):
return 'Concurrently remove index %s from %s' % (self.name, self.model_name)
def database_forwards(self, app_label, schema_editor, from_state, to_state):
self._ensure_not_in_transaction(schema_editor)
model = from_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
from_model_state = from_state.models[app_label, self.model_name_lower]
index = from_model_state.get_index_by_name(self.name)
schema_editor.remove_index(model, index, concurrently=True)
def database_backwards(self, app_label, schema_editor, from_state, to_state):
self._ensure_not_in_transaction(schema_editor)
model = to_state.apps.get_model(app_label, self.model_name)
if self.allow_migrate_model(schema_editor.connection.alias, model):
to_model_state = to_state.models[app_label, self.model_name_lower]
index = to_model_state.get_index_by_name(self.name)
schema_editor.add_index(model, index, concurrently=True)
|
3f35a8a5493187925192a028cc937e45a2ecee0c1a2a15f31e4204ef9c90fa0e | from django.db.models import Transform
from django.db.models.lookups import PostgresOperatorLookup
from .search import SearchVector, SearchVectorExact, SearchVectorField
class DataContains(PostgresOperatorLookup):
lookup_name = 'contains'
postgres_operator = '@>'
class ContainedBy(PostgresOperatorLookup):
lookup_name = 'contained_by'
postgres_operator = '<@'
class Overlap(PostgresOperatorLookup):
lookup_name = 'overlap'
postgres_operator = '&&'
class HasKey(PostgresOperatorLookup):
lookup_name = 'has_key'
postgres_operator = '?'
prepare_rhs = False
class HasKeys(PostgresOperatorLookup):
lookup_name = 'has_keys'
postgres_operator = '?&'
def get_prep_lookup(self):
return [str(item) for item in self.rhs]
class HasAnyKeys(HasKeys):
lookup_name = 'has_any_keys'
postgres_operator = '?|'
class Unaccent(Transform):
bilateral = True
lookup_name = 'unaccent'
function = 'UNACCENT'
class SearchLookup(SearchVectorExact):
lookup_name = 'search'
def process_lhs(self, qn, connection):
if not isinstance(self.lhs.output_field, SearchVectorField):
config = getattr(self.rhs, 'config', None)
self.lhs = SearchVector(self.lhs, config=config)
lhs, lhs_params = super().process_lhs(qn, connection)
return lhs, lhs_params
class TrigramSimilar(PostgresOperatorLookup):
lookup_name = 'trigram_similar'
postgres_operator = '%%'
|
f40971d33831e4d6e15944d21022678880c88878a511d7f5c0bf8f5d8cfa2605 | from django.db.backends.ddl_references import Statement, Table
from django.db.models import Deferrable, F, Q
from django.db.models.constraints import BaseConstraint
from django.db.models.sql import Query
__all__ = ['ExclusionConstraint']
class ExclusionConstraint(BaseConstraint):
template = 'CONSTRAINT %(name)s EXCLUDE USING %(index_type)s (%(expressions)s)%(where)s%(deferrable)s'
def __init__(
self, *, name, expressions, index_type=None, condition=None,
deferrable=None,
):
if index_type and index_type.lower() not in {'gist', 'spgist'}:
raise ValueError(
'Exclusion constraints only support GiST or SP-GiST indexes.'
)
if not expressions:
raise ValueError(
'At least one expression is required to define an exclusion '
'constraint.'
)
if not all(
isinstance(expr, (list, tuple)) and len(expr) == 2
for expr in expressions
):
raise ValueError('The expressions must be a list of 2-tuples.')
if not isinstance(condition, (type(None), Q)):
raise ValueError(
'ExclusionConstraint.condition must be a Q instance.'
)
if condition and deferrable:
raise ValueError(
'ExclusionConstraint with conditions cannot be deferred.'
)
if not isinstance(deferrable, (type(None), Deferrable)):
raise ValueError(
'ExclusionConstraint.deferrable must be a Deferrable instance.'
)
self.expressions = expressions
self.index_type = index_type or 'GIST'
self.condition = condition
self.deferrable = deferrable
super().__init__(name=name)
def _get_expression_sql(self, compiler, connection, query):
expressions = []
for expression, operator in self.expressions:
if isinstance(expression, str):
expression = F(expression)
expression = expression.resolve_expression(query=query)
sql, params = expression.as_sql(compiler, connection)
expressions.append('%s WITH %s' % (sql % params, operator))
return expressions
def _get_condition_sql(self, compiler, schema_editor, query):
if self.condition is None:
return None
where = query.build_where(self.condition)
sql, params = where.as_sql(compiler, schema_editor.connection)
return sql % tuple(schema_editor.quote_value(p) for p in params)
def constraint_sql(self, model, schema_editor):
query = Query(model, alias_cols=False)
compiler = query.get_compiler(connection=schema_editor.connection)
expressions = self._get_expression_sql(compiler, schema_editor.connection, query)
condition = self._get_condition_sql(compiler, schema_editor, query)
return self.template % {
'name': schema_editor.quote_name(self.name),
'index_type': self.index_type,
'expressions': ', '.join(expressions),
'where': ' WHERE (%s)' % condition if condition else '',
'deferrable': schema_editor._deferrable_constraint_sql(self.deferrable),
}
def create_sql(self, model, schema_editor):
return Statement(
'ALTER TABLE %(table)s ADD %(constraint)s',
table=Table(model._meta.db_table, schema_editor.quote_name),
constraint=self.constraint_sql(model, schema_editor),
)
def remove_sql(self, model, schema_editor):
return schema_editor._delete_constraint_sql(
schema_editor.sql_delete_check,
model,
schema_editor.quote_name(self.name),
)
def deconstruct(self):
path, args, kwargs = super().deconstruct()
kwargs['expressions'] = self.expressions
if self.condition is not None:
kwargs['condition'] = self.condition
if self.index_type.lower() != 'gist':
kwargs['index_type'] = self.index_type
if self.deferrable:
kwargs['deferrable'] = self.deferrable
return path, args, kwargs
def __eq__(self, other):
if isinstance(other, self.__class__):
return (
self.name == other.name and
self.index_type == other.index_type and
self.expressions == other.expressions and
self.condition == other.condition and
self.deferrable == other.deferrable
)
return super().__eq__(other)
def __repr__(self):
return '<%s: index_type=%s, expressions=%s%s%s>' % (
self.__class__.__qualname__,
self.index_type,
self.expressions,
'' if self.condition is None else ', condition=%s' % self.condition,
'' if self.deferrable is None else ', deferrable=%s' % self.deferrable,
)
|
6736df24c5426830f5ca9c93e8450f657d108853ee5017d909fff00a701ddad4 | import inspect
import re
from django.apps import apps as django_apps
from django.conf import settings
from django.core.exceptions import ImproperlyConfigured, PermissionDenied
from django.middleware.csrf import rotate_token
from django.utils.crypto import constant_time_compare
from django.utils.module_loading import import_string
from .signals import user_logged_in, user_logged_out, user_login_failed
SESSION_KEY = '_auth_user_id'
BACKEND_SESSION_KEY = '_auth_user_backend'
HASH_SESSION_KEY = '_auth_user_hash'
REDIRECT_FIELD_NAME = 'next'
def load_backend(path):
return import_string(path)()
def _get_backends(return_tuples=False):
backends = []
for backend_path in settings.AUTHENTICATION_BACKENDS:
backend = load_backend(backend_path)
backends.append((backend, backend_path) if return_tuples else backend)
if not backends:
raise ImproperlyConfigured(
'No authentication backends have been defined. Does '
'AUTHENTICATION_BACKENDS contain anything?'
)
return backends
def get_backends():
return _get_backends(return_tuples=False)
def _clean_credentials(credentials):
"""
Clean a dictionary of credentials of potentially sensitive info before
sending to less secure functions.
Not comprehensive - intended for user_login_failed signal
"""
SENSITIVE_CREDENTIALS = re.compile('api|token|key|secret|password|signature', re.I)
CLEANSED_SUBSTITUTE = '********************'
for key in credentials:
if SENSITIVE_CREDENTIALS.search(key):
credentials[key] = CLEANSED_SUBSTITUTE
return credentials
def _get_user_session_key(request):
# This value in the session is always serialized to a string, so we need
# to convert it back to Python whenever we access it.
return get_user_model()._meta.pk.to_python(request.session[SESSION_KEY])
def authenticate(request=None, **credentials):
"""
If the given credentials are valid, return a User object.
"""
for backend, backend_path in _get_backends(return_tuples=True):
backend_signature = inspect.signature(backend.authenticate)
try:
backend_signature.bind(request, **credentials)
except TypeError:
# This backend doesn't accept these credentials as arguments. Try the next one.
continue
try:
user = backend.authenticate(request, **credentials)
except PermissionDenied:
# This backend says to stop in our tracks - this user should not be allowed in at all.
break
if user is None:
continue
# Annotate the user object with the path of the backend.
user.backend = backend_path
return user
# The credentials supplied are invalid to all backends, fire signal
user_login_failed.send(sender=__name__, credentials=_clean_credentials(credentials), request=request)
def login(request, user, backend=None):
"""
Persist a user id and a backend in the request. This way a user doesn't
have to reauthenticate on every request. Note that data set during
the anonymous session is retained when the user logs in.
"""
session_auth_hash = ''
if user is None:
user = request.user
if hasattr(user, 'get_session_auth_hash'):
session_auth_hash = user.get_session_auth_hash()
if SESSION_KEY in request.session:
if _get_user_session_key(request) != user.pk or (
session_auth_hash and
not constant_time_compare(request.session.get(HASH_SESSION_KEY, ''), session_auth_hash)):
# To avoid reusing another user's session, create a new, empty
# session if the existing session corresponds to a different
# authenticated user.
request.session.flush()
else:
request.session.cycle_key()
try:
backend = backend or user.backend
except AttributeError:
backends = _get_backends(return_tuples=True)
if len(backends) == 1:
_, backend = backends[0]
else:
raise ValueError(
'You have multiple authentication backends configured and '
'therefore must provide the `backend` argument or set the '
'`backend` attribute on the user.'
)
else:
if not isinstance(backend, str):
raise TypeError('backend must be a dotted import path string (got %r).' % backend)
request.session[SESSION_KEY] = user._meta.pk.value_to_string(user)
request.session[BACKEND_SESSION_KEY] = backend
request.session[HASH_SESSION_KEY] = session_auth_hash
if hasattr(request, 'user'):
request.user = user
rotate_token(request)
user_logged_in.send(sender=user.__class__, request=request, user=user)
def logout(request):
"""
Remove the authenticated user's ID from the request and flush their session
data.
"""
# Dispatch the signal before the user is logged out so the receivers have a
# chance to find out *who* logged out.
user = getattr(request, 'user', None)
if not getattr(user, 'is_authenticated', True):
user = None
user_logged_out.send(sender=user.__class__, request=request, user=user)
request.session.flush()
if hasattr(request, 'user'):
from django.contrib.auth.models import AnonymousUser
request.user = AnonymousUser()
def get_user_model():
"""
Return the User model that is active in this project.
"""
try:
return django_apps.get_model(settings.AUTH_USER_MODEL, require_ready=False)
except ValueError:
raise ImproperlyConfigured("AUTH_USER_MODEL must be of the form 'app_label.model_name'")
except LookupError:
raise ImproperlyConfigured(
"AUTH_USER_MODEL refers to model '%s' that has not been installed" % settings.AUTH_USER_MODEL
)
def get_user(request):
"""
Return the user model instance associated with the given request session.
If no user is retrieved, return an instance of `AnonymousUser`.
"""
from .models import AnonymousUser
user = None
try:
user_id = _get_user_session_key(request)
backend_path = request.session[BACKEND_SESSION_KEY]
except KeyError:
pass
else:
if backend_path in settings.AUTHENTICATION_BACKENDS:
backend = load_backend(backend_path)
user = backend.get_user(user_id)
# Verify the session
if hasattr(user, 'get_session_auth_hash'):
session_hash = request.session.get(HASH_SESSION_KEY)
session_hash_verified = session_hash and constant_time_compare(
session_hash,
user.get_session_auth_hash()
)
if not session_hash_verified:
if not (
session_hash and
hasattr(user, '_legacy_get_session_auth_hash') and
constant_time_compare(session_hash, user._legacy_get_session_auth_hash())
):
request.session.flush()
user = None
return user or AnonymousUser()
def get_permission_codename(action, opts):
"""
Return the codename of the permission for the specified action.
"""
return '%s_%s' % (action, opts.model_name)
def update_session_auth_hash(request, user):
"""
Updating a user's password logs out all sessions for the user.
Take the current request and the updated user object from which the new
session hash will be derived and update the session hash appropriately to
prevent a password change from logging out the session from which the
password was changed.
"""
request.session.cycle_key()
if hasattr(user, 'get_session_auth_hash') and request.user == user:
request.session[HASH_SESSION_KEY] = user.get_session_auth_hash()
default_app_config = 'django.contrib.auth.apps.AuthConfig'
|
6df3c47cc7753c7f8ae87d5a308cd704359a5910beed89e7a1e17c205e17b2f7 | from itertools import chain
from types import MethodType
from django.apps import apps
from django.conf import settings
from django.core import checks
from .management import _get_builtin_permissions
def check_user_model(app_configs=None, **kwargs):
if app_configs is None:
cls = apps.get_model(settings.AUTH_USER_MODEL)
else:
app_label, model_name = settings.AUTH_USER_MODEL.split('.')
for app_config in app_configs:
if app_config.label == app_label:
cls = app_config.get_model(model_name)
break
else:
# Checks might be run against a set of app configs that don't
# include the specified user model. In this case we simply don't
# perform the checks defined below.
return []
errors = []
# Check that REQUIRED_FIELDS is a list
if not isinstance(cls.REQUIRED_FIELDS, (list, tuple)):
errors.append(
checks.Error(
"'REQUIRED_FIELDS' must be a list or tuple.",
obj=cls,
id='auth.E001',
)
)
# Check that the USERNAME FIELD isn't included in REQUIRED_FIELDS.
if cls.USERNAME_FIELD in cls.REQUIRED_FIELDS:
errors.append(
checks.Error(
"The field named as the 'USERNAME_FIELD' "
"for a custom user model must not be included in 'REQUIRED_FIELDS'.",
hint=(
"The 'USERNAME_FIELD' is currently set to '%s', you "
"should remove '%s' from the 'REQUIRED_FIELDS'."
% (cls.USERNAME_FIELD, cls.USERNAME_FIELD)
),
obj=cls,
id='auth.E002',
)
)
# Check that the username field is unique
if not cls._meta.get_field(cls.USERNAME_FIELD).unique:
if (settings.AUTHENTICATION_BACKENDS ==
['django.contrib.auth.backends.ModelBackend']):
errors.append(
checks.Error(
"'%s.%s' must be unique because it is named as the 'USERNAME_FIELD'." % (
cls._meta.object_name, cls.USERNAME_FIELD
),
obj=cls,
id='auth.E003',
)
)
else:
errors.append(
checks.Warning(
"'%s.%s' is named as the 'USERNAME_FIELD', but it is not unique." % (
cls._meta.object_name, cls.USERNAME_FIELD
),
hint='Ensure that your authentication backend(s) can handle non-unique usernames.',
obj=cls,
id='auth.W004',
)
)
if isinstance(cls().is_anonymous, MethodType):
errors.append(
checks.Critical(
'%s.is_anonymous must be an attribute or property rather than '
'a method. Ignoring this is a security issue as anonymous '
'users will be treated as authenticated!' % cls,
obj=cls,
id='auth.C009',
)
)
if isinstance(cls().is_authenticated, MethodType):
errors.append(
checks.Critical(
'%s.is_authenticated must be an attribute or property rather '
'than a method. Ignoring this is a security issue as anonymous '
'users will be treated as authenticated!' % cls,
obj=cls,
id='auth.C010',
)
)
return errors
def check_models_permissions(app_configs=None, **kwargs):
if app_configs is None:
models = apps.get_models()
else:
models = chain.from_iterable(app_config.get_models() for app_config in app_configs)
Permission = apps.get_model('auth', 'Permission')
permission_name_max_length = Permission._meta.get_field('name').max_length
permission_codename_max_length = Permission._meta.get_field('codename').max_length
errors = []
for model in models:
opts = model._meta
builtin_permissions = dict(_get_builtin_permissions(opts))
# Check builtin permission name length.
max_builtin_permission_name_length = (
max(len(name) for name in builtin_permissions.values())
if builtin_permissions else 0
)
if max_builtin_permission_name_length > permission_name_max_length:
verbose_name_max_length = (
permission_name_max_length - (max_builtin_permission_name_length - len(opts.verbose_name_raw))
)
errors.append(
checks.Error(
"The verbose_name of model '%s' must be at most %d "
"characters for its builtin permission names to be at "
"most %d characters." % (
opts.label, verbose_name_max_length, permission_name_max_length
),
obj=model,
id='auth.E007',
)
)
# Check builtin permission codename length.
max_builtin_permission_codename_length = (
max(len(codename) for codename in builtin_permissions.keys())
if builtin_permissions else 0
)
if max_builtin_permission_codename_length > permission_codename_max_length:
model_name_max_length = permission_codename_max_length - (
max_builtin_permission_codename_length - len(opts.model_name)
)
errors.append(
checks.Error(
"The name of model '%s' must be at most %d characters "
"for its builtin permission codenames to be at most %d "
"characters." % (
opts.label,
model_name_max_length,
permission_codename_max_length,
),
obj=model,
id='auth.E011',
)
)
codenames = set()
for codename, name in opts.permissions:
# Check custom permission name length.
if len(name) > permission_name_max_length:
errors.append(
checks.Error(
"The permission named '%s' of model '%s' is longer "
"than %d characters." % (
name, opts.label, permission_name_max_length,
),
obj=model,
id='auth.E008',
)
)
# Check custom permission codename length.
if len(codename) > permission_codename_max_length:
errors.append(
checks.Error(
"The permission codenamed '%s' of model '%s' is "
"longer than %d characters." % (
codename,
opts.label,
permission_codename_max_length,
),
obj=model,
id='auth.E012',
)
)
# Check custom permissions codename clashing.
if codename in builtin_permissions:
errors.append(
checks.Error(
"The permission codenamed '%s' clashes with a builtin permission "
"for model '%s'." % (codename, opts.label),
obj=model,
id='auth.E005',
)
)
elif codename in codenames:
errors.append(
checks.Error(
"The permission codenamed '%s' is duplicated for "
"model '%s'." % (codename, opts.label),
obj=model,
id='auth.E006',
)
)
codenames.add(codename)
return errors
|
de040690c10f1f0193368d9a3982c0cd049f9a7676c135a8db4250e227652f3f | from django.contrib import auth
from django.contrib.auth.base_user import AbstractBaseUser, BaseUserManager
from django.contrib.contenttypes.models import ContentType
from django.core.exceptions import PermissionDenied
from django.core.mail import send_mail
from django.db import models
from django.db.models.manager import EmptyManager
from django.utils import timezone
from django.utils.translation import gettext_lazy as _
from .validators import UnicodeUsernameValidator
def update_last_login(sender, user, **kwargs):
"""
A signal receiver which updates the last_login date for
the user logging in.
"""
user.last_login = timezone.now()
user.save(update_fields=['last_login'])
class PermissionManager(models.Manager):
use_in_migrations = True
def get_by_natural_key(self, codename, app_label, model):
return self.get(
codename=codename,
content_type=ContentType.objects.db_manager(self.db).get_by_natural_key(app_label, model),
)
class Permission(models.Model):
"""
The permissions system provides a way to assign permissions to specific
users and groups of users.
The permission system is used by the Django admin site, but may also be
useful in your own code. The Django admin site uses permissions as follows:
- The "add" permission limits the user's ability to view the "add" form
and add an object.
- The "change" permission limits a user's ability to view the change
list, view the "change" form and change an object.
- The "delete" permission limits the ability to delete an object.
- The "view" permission limits the ability to view an object.
Permissions are set globally per type of object, not per specific object
instance. It is possible to say "Mary may change news stories," but it's
not currently possible to say "Mary may change news stories, but only the
ones she created herself" or "Mary may only change news stories that have a
certain status or publication date."
The permissions listed above are automatically created for each model.
"""
name = models.CharField(_('name'), max_length=255)
content_type = models.ForeignKey(
ContentType,
models.CASCADE,
verbose_name=_('content type'),
)
codename = models.CharField(_('codename'), max_length=100)
objects = PermissionManager()
class Meta:
verbose_name = _('permission')
verbose_name_plural = _('permissions')
unique_together = [['content_type', 'codename']]
ordering = ['content_type__app_label', 'content_type__model', 'codename']
def __str__(self):
return '%s | %s' % (self.content_type, self.name)
def natural_key(self):
return (self.codename,) + self.content_type.natural_key()
natural_key.dependencies = ['contenttypes.contenttype']
class GroupManager(models.Manager):
"""
The manager for the auth's Group model.
"""
use_in_migrations = True
def get_by_natural_key(self, name):
return self.get(name=name)
class Group(models.Model):
"""
Groups are a generic way of categorizing users to apply permissions, or
some other label, to those users. A user can belong to any number of
groups.
A user in a group automatically has all the permissions granted to that
group. For example, if the group 'Site editors' has the permission
can_edit_home_page, any user in that group will have that permission.
Beyond permissions, groups are a convenient way to categorize users to
apply some label, or extended functionality, to them. For example, you
could create a group 'Special users', and you could write code that would
do special things to those users -- such as giving them access to a
members-only portion of your site, or sending them members-only email
messages.
"""
name = models.CharField(_('name'), max_length=150, unique=True)
permissions = models.ManyToManyField(
Permission,
verbose_name=_('permissions'),
blank=True,
)
objects = GroupManager()
class Meta:
verbose_name = _('group')
verbose_name_plural = _('groups')
def __str__(self):
return self.name
def natural_key(self):
return (self.name,)
class UserManager(BaseUserManager):
use_in_migrations = True
def _create_user(self, username, email, password, **extra_fields):
"""
Create and save a user with the given username, email, and password.
"""
if not username:
raise ValueError('The given username must be set')
email = self.normalize_email(email)
username = self.model.normalize_username(username)
user = self.model(username=username, email=email, **extra_fields)
user.set_password(password)
user.save(using=self._db)
return user
def create_user(self, username, email=None, password=None, **extra_fields):
extra_fields.setdefault('is_staff', False)
extra_fields.setdefault('is_superuser', False)
return self._create_user(username, email, password, **extra_fields)
def create_superuser(self, username, email=None, password=None, **extra_fields):
extra_fields.setdefault('is_staff', True)
extra_fields.setdefault('is_superuser', True)
if extra_fields.get('is_staff') is not True:
raise ValueError('Superuser must have is_staff=True.')
if extra_fields.get('is_superuser') is not True:
raise ValueError('Superuser must have is_superuser=True.')
return self._create_user(username, email, password, **extra_fields)
def with_perm(self, perm, is_active=True, include_superusers=True, backend=None, obj=None):
if backend is None:
backends = auth._get_backends(return_tuples=True)
if len(backends) == 1:
backend, _ = backends[0]
else:
raise ValueError(
'You have multiple authentication backends configured and '
'therefore must provide the `backend` argument.'
)
elif not isinstance(backend, str):
raise TypeError(
'backend must be a dotted import path string (got %r).'
% backend
)
else:
backend = auth.load_backend(backend)
if hasattr(backend, 'with_perm'):
return backend.with_perm(
perm,
is_active=is_active,
include_superusers=include_superusers,
obj=obj,
)
return self.none()
# A few helper functions for common logic between User and AnonymousUser.
def _user_get_permissions(user, obj, from_name):
permissions = set()
name = 'get_%s_permissions' % from_name
for backend in auth.get_backends():
if hasattr(backend, name):
permissions.update(getattr(backend, name)(user, obj))
return permissions
def _user_has_perm(user, perm, obj):
"""
A backend can raise `PermissionDenied` to short-circuit permission checking.
"""
for backend in auth.get_backends():
if not hasattr(backend, 'has_perm'):
continue
try:
if backend.has_perm(user, perm, obj):
return True
except PermissionDenied:
return False
return False
def _user_has_module_perms(user, app_label):
"""
A backend can raise `PermissionDenied` to short-circuit permission checking.
"""
for backend in auth.get_backends():
if not hasattr(backend, 'has_module_perms'):
continue
try:
if backend.has_module_perms(user, app_label):
return True
except PermissionDenied:
return False
return False
class PermissionsMixin(models.Model):
"""
Add the fields and methods necessary to support the Group and Permission
models using the ModelBackend.
"""
is_superuser = models.BooleanField(
_('superuser status'),
default=False,
help_text=_(
'Designates that this user has all permissions without '
'explicitly assigning them.'
),
)
groups = models.ManyToManyField(
Group,
verbose_name=_('groups'),
blank=True,
help_text=_(
'The groups this user belongs to. A user will get all permissions '
'granted to each of their groups.'
),
related_name="user_set",
related_query_name="user",
)
user_permissions = models.ManyToManyField(
Permission,
verbose_name=_('user permissions'),
blank=True,
help_text=_('Specific permissions for this user.'),
related_name="user_set",
related_query_name="user",
)
class Meta:
abstract = True
def get_user_permissions(self, obj=None):
"""
Return a list of permission strings that this user has directly.
Query all available auth backends. If an object is passed in,
return only permissions matching this object.
"""
return _user_get_permissions(self, obj, 'user')
def get_group_permissions(self, obj=None):
"""
Return a list of permission strings that this user has through their
groups. Query all available auth backends. If an object is passed in,
return only permissions matching this object.
"""
return _user_get_permissions(self, obj, 'group')
def get_all_permissions(self, obj=None):
return _user_get_permissions(self, obj, 'all')
def has_perm(self, perm, obj=None):
"""
Return True if the user has the specified permission. Query all
available auth backends, but return immediately if any backend returns
True. Thus, a user who has permission from a single auth backend is
assumed to have permission in general. If an object is provided, check
permissions for that object.
"""
# Active superusers have all permissions.
if self.is_active and self.is_superuser:
return True
# Otherwise we need to check the backends.
return _user_has_perm(self, perm, obj)
def has_perms(self, perm_list, obj=None):
"""
Return True if the user has each of the specified permissions. If
object is passed, check if the user has all required perms for it.
"""
return all(self.has_perm(perm, obj) for perm in perm_list)
def has_module_perms(self, app_label):
"""
Return True if the user has any permissions in the given app label.
Use similar logic as has_perm(), above.
"""
# Active superusers have all permissions.
if self.is_active and self.is_superuser:
return True
return _user_has_module_perms(self, app_label)
class AbstractUser(AbstractBaseUser, PermissionsMixin):
"""
An abstract base class implementing a fully featured User model with
admin-compliant permissions.
Username and password are required. Other fields are optional.
"""
username_validator = UnicodeUsernameValidator()
username = models.CharField(
_('username'),
max_length=150,
unique=True,
help_text=_('Required. 150 characters or fewer. Letters, digits and @/./+/-/_ only.'),
validators=[username_validator],
error_messages={
'unique': _("A user with that username already exists."),
},
)
first_name = models.CharField(_('first name'), max_length=150, blank=True)
last_name = models.CharField(_('last name'), max_length=150, blank=True)
email = models.EmailField(_('email address'), blank=True)
is_staff = models.BooleanField(
_('staff status'),
default=False,
help_text=_('Designates whether the user can log into this admin site.'),
)
is_active = models.BooleanField(
_('active'),
default=True,
help_text=_(
'Designates whether this user should be treated as active. '
'Unselect this instead of deleting accounts.'
),
)
date_joined = models.DateTimeField(_('date joined'), default=timezone.now)
objects = UserManager()
EMAIL_FIELD = 'email'
USERNAME_FIELD = 'username'
REQUIRED_FIELDS = ['email']
class Meta:
verbose_name = _('user')
verbose_name_plural = _('users')
abstract = True
def clean(self):
super().clean()
self.email = self.__class__.objects.normalize_email(self.email)
def get_full_name(self):
"""
Return the first_name plus the last_name, with a space in between.
"""
full_name = '%s %s' % (self.first_name, self.last_name)
return full_name.strip()
def get_short_name(self):
"""Return the short name for the user."""
return self.first_name
def email_user(self, subject, message, from_email=None, **kwargs):
"""Send an email to this user."""
send_mail(subject, message, from_email, [self.email], **kwargs)
class User(AbstractUser):
"""
Users within the Django authentication system are represented by this
model.
Username and password are required. Other fields are optional.
"""
class Meta(AbstractUser.Meta):
swappable = 'AUTH_USER_MODEL'
class AnonymousUser:
id = None
pk = None
username = ''
is_staff = False
is_active = False
is_superuser = False
_groups = EmptyManager(Group)
_user_permissions = EmptyManager(Permission)
def __str__(self):
return 'AnonymousUser'
def __eq__(self, other):
return isinstance(other, self.__class__)
def __hash__(self):
return 1 # instances always return the same hash value
def __int__(self):
raise TypeError('Cannot cast AnonymousUser to int. Are you trying to use it in place of User?')
def save(self):
raise NotImplementedError("Django doesn't provide a DB representation for AnonymousUser.")
def delete(self):
raise NotImplementedError("Django doesn't provide a DB representation for AnonymousUser.")
def set_password(self, raw_password):
raise NotImplementedError("Django doesn't provide a DB representation for AnonymousUser.")
def check_password(self, raw_password):
raise NotImplementedError("Django doesn't provide a DB representation for AnonymousUser.")
@property
def groups(self):
return self._groups
@property
def user_permissions(self):
return self._user_permissions
def get_user_permissions(self, obj=None):
return _user_get_permissions(self, obj, 'user')
def get_group_permissions(self, obj=None):
return set()
def get_all_permissions(self, obj=None):
return _user_get_permissions(self, obj, 'all')
def has_perm(self, perm, obj=None):
return _user_has_perm(self, perm, obj=obj)
def has_perms(self, perm_list, obj=None):
return all(self.has_perm(perm, obj) for perm in perm_list)
def has_module_perms(self, module):
return _user_has_module_perms(self, module)
@property
def is_anonymous(self):
return True
@property
def is_authenticated(self):
return False
def get_username(self):
return self.username
|
21a05e5e4ab36ddb853dcb3bf6cf3d7a13d6eef9299ec1ede9e89821b6b67d6b | from datetime import datetime
from django.conf import settings
from django.utils.crypto import constant_time_compare, salted_hmac
from django.utils.http import base36_to_int, int_to_base36
class PasswordResetTokenGenerator:
"""
Strategy object used to generate and check tokens for the password
reset mechanism.
"""
key_salt = "django.contrib.auth.tokens.PasswordResetTokenGenerator"
algorithm = 'sha256'
secret = settings.SECRET_KEY
def make_token(self, user):
"""
Return a token that can be used once to do a password reset
for the given user.
"""
return self._make_token_with_timestamp(user, self._num_seconds(self._now()))
def check_token(self, user, token):
"""
Check that a password reset token is correct for a given user.
"""
if not (user and token):
return False
# Parse the token
try:
ts_b36, _ = token.split("-")
except ValueError:
return False
try:
ts = base36_to_int(ts_b36)
except ValueError:
return False
# Check that the timestamp/uid has not been tampered with
if not constant_time_compare(self._make_token_with_timestamp(user, ts), token):
# RemovedInDjango40Warning: when the deprecation ends, replace
# with:
# return False
if not constant_time_compare(
self._make_token_with_timestamp(user, ts, legacy=True),
token,
):
return False
# Check the timestamp is within limit.
if (self._num_seconds(self._now()) - ts) > settings.PASSWORD_RESET_TIMEOUT:
return False
return True
def _make_token_with_timestamp(self, user, timestamp, legacy=False):
# timestamp is number of seconds since 2001-1-1. Converted to base 36,
# this gives us a 6 digit string until about 2069.
ts_b36 = int_to_base36(timestamp)
hash_string = salted_hmac(
self.key_salt,
self._make_hash_value(user, timestamp),
secret=self.secret,
# RemovedInDjango40Warning: when the deprecation ends, remove the
# legacy argument and replace with:
# algorithm=self.algorithm,
algorithm='sha1' if legacy else self.algorithm,
).hexdigest()[::2] # Limit to 20 characters to shorten the URL.
return "%s-%s" % (ts_b36, hash_string)
def _make_hash_value(self, user, timestamp):
"""
Hash the user's primary key and some user state that's sure to change
after a password reset to produce a token that invalidated when it's
used:
1. The password field will change upon a password reset (even if the
same password is chosen, due to password salting).
2. The last_login field will usually be updated very shortly after
a password reset.
Failing those things, settings.PASSWORD_RESET_TIMEOUT eventually
invalidates the token.
Running this data through salted_hmac() prevents password cracking
attempts using the reset token, provided the secret isn't compromised.
"""
# Truncate microseconds so that tokens are consistent even if the
# database doesn't support microseconds.
login_timestamp = '' if user.last_login is None else user.last_login.replace(microsecond=0, tzinfo=None)
return str(user.pk) + user.password + str(login_timestamp) + str(timestamp)
def _num_seconds(self, dt):
return int((dt - datetime(2001, 1, 1)).total_seconds())
def _now(self):
# Used for mocking in tests
return datetime.now()
default_token_generator = PasswordResetTokenGenerator()
|
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