Spaces:
Running
Running
File size: 34,204 Bytes
2a0bc63 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 |
# Copyright DataStax, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from copy import deepcopy, copy
from datetime import date, datetime, timedelta
import logging
from uuid import UUID as _UUID
from cassandra import util
from cassandra.cqltypes import SimpleDateType, _cqltypes, UserType
from cassandra.cqlengine import ValidationError
from cassandra.cqlengine.functions import get_total_seconds
from cassandra.util import Duration as _Duration
log = logging.getLogger(__name__)
class BaseValueManager(object):
def __init__(self, instance, column, value):
self.instance = instance
self.column = column
self.value = value
self.previous_value = None
self.explicit = False
@property
def deleted(self):
return self.column._val_is_null(self.value) and (self.explicit or not self.column._val_is_null(self.previous_value))
@property
def changed(self):
"""
Indicates whether or not this value has changed.
:rtype: boolean
"""
if self.explicit:
return self.value != self.previous_value
if isinstance(self.column, BaseContainerColumn):
default_value = self.column.get_default()
if self.column._val_is_null(default_value):
return not self.column._val_is_null(self.value) and self.value != self.previous_value
elif self.previous_value is None:
return self.value != default_value
return self.value != self.previous_value
return False
def reset_previous_value(self):
self.previous_value = deepcopy(self.value)
def getval(self):
return self.value
def setval(self, val):
self.value = val
self.explicit = True
def delval(self):
self.value = None
def get_property(self):
_get = lambda slf: self.getval()
_set = lambda slf, val: self.setval(val)
_del = lambda slf: self.delval()
if self.column.can_delete:
return property(_get, _set, _del)
else:
return property(_get, _set)
class Column(object):
# the cassandra type this column maps to
db_type = None
value_manager = BaseValueManager
instance_counter = 0
_python_type_hashable = True
primary_key = False
"""
bool flag, indicates this column is a primary key. The first primary key defined
on a model is the partition key (unless partition keys are set), all others are cluster keys
"""
partition_key = False
"""
indicates that this column should be the partition key, defining
more than one partition key column creates a compound partition key
"""
index = False
"""
bool flag, indicates an index should be created for this column
"""
custom_index = False
"""
bool flag, indicates an index is managed outside of cqlengine. This is
useful if you want to do filter queries on fields that have custom
indexes.
"""
db_field = None
"""
the fieldname this field will map to in the database
"""
default = None
"""
the default value, can be a value or a callable (no args)
"""
required = False
"""
boolean, is the field required? Model validation will raise and
exception if required is set to True and there is a None value assigned
"""
clustering_order = None
"""
only applicable on clustering keys (primary keys that are not partition keys)
determines the order that the clustering keys are sorted on disk
"""
discriminator_column = False
"""
boolean, if set to True, this column will be used for discriminating records
of inherited models.
Should only be set on a column of an abstract model being used for inheritance.
There may only be one discriminator column per model. See :attr:`~.__discriminator_value__`
for how to specify the value of this column on specialized models.
"""
static = False
"""
boolean, if set to True, this is a static column, with a single value per partition
"""
def __init__(self,
primary_key=False,
partition_key=False,
index=False,
db_field=None,
default=None,
required=False,
clustering_order=None,
discriminator_column=False,
static=False,
custom_index=False):
self.partition_key = partition_key
self.primary_key = partition_key or primary_key
self.index = index
self.custom_index = custom_index
self.db_field = db_field
self.default = default
self.required = required
self.clustering_order = clustering_order
self.discriminator_column = discriminator_column
# the column name in the model definition
self.column_name = None
self._partition_key_index = None
self.static = static
self.value = None
# keep track of instantiation order
self.position = Column.instance_counter
Column.instance_counter += 1
def __ne__(self, other):
if isinstance(other, Column):
return self.position != other.position
return NotImplemented
def __eq__(self, other):
if isinstance(other, Column):
return self.position == other.position
return NotImplemented
def __lt__(self, other):
if isinstance(other, Column):
return self.position < other.position
return NotImplemented
def __le__(self, other):
if isinstance(other, Column):
return self.position <= other.position
return NotImplemented
def __gt__(self, other):
if isinstance(other, Column):
return self.position > other.position
return NotImplemented
def __ge__(self, other):
if isinstance(other, Column):
return self.position >= other.position
return NotImplemented
def __hash__(self):
return id(self)
def validate(self, value):
"""
Returns a cleaned and validated value. Raises a ValidationError
if there's a problem
"""
if value is None:
if self.required:
raise ValidationError('{0} - None values are not allowed'.format(self.column_name or self.db_field))
return value
def to_python(self, value):
"""
Converts data from the database into python values
raises a ValidationError if the value can't be converted
"""
return value
def to_database(self, value):
"""
Converts python value into database value
"""
return value
@property
def has_default(self):
return self.default is not None
@property
def is_primary_key(self):
return self.primary_key
@property
def can_delete(self):
return not self.primary_key
def get_default(self):
if self.has_default:
if callable(self.default):
return self.default()
else:
return self.default
def get_column_def(self):
"""
Returns a column definition for CQL table definition
"""
static = "static" if self.static else ""
return '{0} {1} {2}'.format(self.cql, self.db_type, static)
# TODO: make columns use cqltypes under the hood
# until then, this bridges the gap in using types along with cassandra.metadata for CQL generation
def cql_parameterized_type(self):
return self.db_type
def set_column_name(self, name):
"""
Sets the column name during document class construction
This value will be ignored if db_field is set in __init__
"""
self.column_name = name
@property
def db_field_name(self):
""" Returns the name of the cql name of this column """
return self.db_field if self.db_field is not None else self.column_name
@property
def db_index_name(self):
""" Returns the name of the cql index """
return 'index_{0}'.format(self.db_field_name)
@property
def has_index(self):
return self.index or self.custom_index
@property
def cql(self):
return self.get_cql()
def get_cql(self):
return '"{0}"'.format(self.db_field_name)
def _val_is_null(self, val):
""" determines if the given value equates to a null value for the given column type """
return val is None
@property
def sub_types(self):
return []
@property
def cql_type(self):
return _cqltypes[self.db_type]
class Blob(Column):
"""
Stores a raw binary value
"""
db_type = 'blob'
def to_database(self, value):
if not isinstance(value, (bytes, bytearray)):
raise Exception("expecting a binary, got a %s" % type(value))
val = super(Bytes, self).to_database(value)
return bytearray(val)
Bytes = Blob
class Inet(Column):
"""
Stores an IP address in IPv4 or IPv6 format
"""
db_type = 'inet'
class Text(Column):
"""
Stores a UTF-8 encoded string
"""
db_type = 'text'
def __init__(self, min_length=None, max_length=None, **kwargs):
"""
:param int min_length: Sets the minimum length of this string, for validation purposes.
Defaults to 1 if this is a ``required`` column. Otherwise, None.
:param int max_length: Sets the maximum length of this string, for validation purposes.
"""
self.min_length = (
1 if min_length is None and kwargs.get('required', False)
else min_length)
self.max_length = max_length
if self.min_length is not None:
if self.min_length < 0:
raise ValueError(
'Minimum length is not allowed to be negative.')
if self.max_length is not None:
if self.max_length < 0:
raise ValueError(
'Maximum length is not allowed to be negative.')
if self.min_length is not None and self.max_length is not None:
if self.max_length < self.min_length:
raise ValueError(
'Maximum length must be greater or equal '
'to minimum length.')
super(Text, self).__init__(**kwargs)
def validate(self, value):
value = super(Text, self).validate(value)
if not isinstance(value, (str, bytearray)) and value is not None:
raise ValidationError('{0} {1} is not a string'.format(self.column_name, type(value)))
if self.max_length is not None:
if value and len(value) > self.max_length:
raise ValidationError('{0} is longer than {1} characters'.format(self.column_name, self.max_length))
if self.min_length:
if (self.min_length and not value) or len(value) < self.min_length:
raise ValidationError('{0} is shorter than {1} characters'.format(self.column_name, self.min_length))
return value
class Ascii(Text):
"""
Stores a US-ASCII character string
"""
db_type = 'ascii'
def validate(self, value):
""" Only allow ASCII and None values.
Check against US-ASCII, a.k.a. 7-bit ASCII, a.k.a. ISO646-US, a.k.a.
the Basic Latin block of the Unicode character set.
Source: https://github.com/apache/cassandra/blob
/3dcbe90e02440e6ee534f643c7603d50ca08482b/src/java/org/apache/cassandra
/serializers/AsciiSerializer.java#L29
"""
value = super(Ascii, self).validate(value)
if value:
charset = value if isinstance(
value, (bytearray, )) else map(ord, value)
if not set(range(128)).issuperset(charset):
raise ValidationError(
'{!r} is not an ASCII string.'.format(value))
return value
class Integer(Column):
"""
Stores a 32-bit signed integer value
"""
db_type = 'int'
def validate(self, value):
val = super(Integer, self).validate(value)
if val is None:
return
try:
return int(val)
except (TypeError, ValueError):
raise ValidationError("{0} {1} can't be converted to integral value".format(self.column_name, value))
def to_python(self, value):
return self.validate(value)
def to_database(self, value):
return self.validate(value)
class TinyInt(Integer):
"""
Stores an 8-bit signed integer value
.. versionadded:: 2.6.0
requires C* 2.2+ and protocol v4+
"""
db_type = 'tinyint'
class SmallInt(Integer):
"""
Stores a 16-bit signed integer value
.. versionadded:: 2.6.0
requires C* 2.2+ and protocol v4+
"""
db_type = 'smallint'
class BigInt(Integer):
"""
Stores a 64-bit signed integer value
"""
db_type = 'bigint'
class VarInt(Column):
"""
Stores an arbitrary-precision integer
"""
db_type = 'varint'
def validate(self, value):
val = super(VarInt, self).validate(value)
if val is None:
return
try:
return int(val)
except (TypeError, ValueError):
raise ValidationError(
"{0} {1} can't be converted to integral value".format(self.column_name, value))
def to_python(self, value):
return self.validate(value)
def to_database(self, value):
return self.validate(value)
class CounterValueManager(BaseValueManager):
def __init__(self, instance, column, value):
super(CounterValueManager, self).__init__(instance, column, value)
self.value = self.value or 0
self.previous_value = self.previous_value or 0
class Counter(Integer):
"""
Stores a counter that can be incremented and decremented
"""
db_type = 'counter'
value_manager = CounterValueManager
def __init__(self,
index=False,
db_field=None,
required=False):
super(Counter, self).__init__(
primary_key=False,
partition_key=False,
index=index,
db_field=db_field,
default=0,
required=required,
)
class DateTime(Column):
"""
Stores a datetime value
"""
db_type = 'timestamp'
truncate_microseconds = False
"""
Set this ``True`` to have model instances truncate the date, quantizing it in the same way it will be in the database.
This allows equality comparison between assigned values and values read back from the database::
DateTime.truncate_microseconds = True
assert Model.create(id=0, d=datetime.utcnow()) == Model.objects(id=0).first()
Defaults to ``False`` to preserve legacy behavior. May change in the future.
"""
def to_python(self, value):
if value is None:
return
if isinstance(value, datetime):
if DateTime.truncate_microseconds:
us = value.microsecond
truncated_us = us // 1000 * 1000
return value - timedelta(microseconds=us - truncated_us)
else:
return value
elif isinstance(value, date):
return datetime(*(value.timetuple()[:6]))
return datetime.utcfromtimestamp(value)
def to_database(self, value):
value = super(DateTime, self).to_database(value)
if value is None:
return
if not isinstance(value, datetime):
if isinstance(value, date):
value = datetime(value.year, value.month, value.day)
else:
raise ValidationError("{0} '{1}' is not a datetime object".format(self.column_name, value))
epoch = datetime(1970, 1, 1, tzinfo=value.tzinfo)
offset = get_total_seconds(epoch.tzinfo.utcoffset(epoch)) if epoch.tzinfo else 0
return int((get_total_seconds(value - epoch) - offset) * 1000)
class Date(Column):
"""
Stores a simple date, with no time-of-day
.. versionchanged:: 2.6.0
removed overload of Date and DateTime. DateTime is a drop-in replacement for legacy models
requires C* 2.2+ and protocol v4+
"""
db_type = 'date'
def to_database(self, value):
if value is None:
return
# need to translate to int version because some dates are not representable in
# string form (datetime limitation)
d = value if isinstance(value, util.Date) else util.Date(value)
return d.days_from_epoch + SimpleDateType.EPOCH_OFFSET_DAYS
def to_python(self, value):
if value is None:
return
if isinstance(value, util.Date):
return value
if isinstance(value, datetime):
value = value.date()
return util.Date(value)
class Time(Column):
"""
Stores a timezone-naive time-of-day, with nanosecond precision
.. versionadded:: 2.6.0
requires C* 2.2+ and protocol v4+
"""
db_type = 'time'
def to_database(self, value):
value = super(Time, self).to_database(value)
if value is None:
return
# str(util.Time) yields desired CQL encoding
return value if isinstance(value, util.Time) else util.Time(value)
def to_python(self, value):
value = super(Time, self).to_database(value)
if value is None:
return
if isinstance(value, util.Time):
return value
return util.Time(value)
class Duration(Column):
"""
Stores a duration (months, days, nanoseconds)
.. versionadded:: 3.10.0
requires C* 3.10+ and protocol v4+
"""
db_type = 'duration'
def validate(self, value):
val = super(Duration, self).validate(value)
if val is None:
return
if not isinstance(val, _Duration):
raise TypeError('{0} {1} is not a valid Duration.'.format(self.column_name, value))
return val
class UUID(Column):
"""
Stores a type 1 or 4 UUID
"""
db_type = 'uuid'
def validate(self, value):
val = super(UUID, self).validate(value)
if val is None:
return
if isinstance(val, _UUID):
return val
if isinstance(val, str):
try:
return _UUID(val)
except ValueError:
# fall-through to error
pass
raise ValidationError("{0} {1} is not a valid uuid".format(
self.column_name, value))
def to_python(self, value):
return self.validate(value)
def to_database(self, value):
return self.validate(value)
class TimeUUID(UUID):
"""
UUID containing timestamp
"""
db_type = 'timeuuid'
class Boolean(Column):
"""
Stores a boolean True or False value
"""
db_type = 'boolean'
def validate(self, value):
""" Always returns a Python boolean. """
value = super(Boolean, self).validate(value)
if value is not None:
value = bool(value)
return value
def to_python(self, value):
return self.validate(value)
class BaseFloat(Column):
def validate(self, value):
value = super(BaseFloat, self).validate(value)
if value is None:
return
try:
return float(value)
except (TypeError, ValueError):
raise ValidationError("{0} {1} is not a valid float".format(self.column_name, value))
def to_python(self, value):
return self.validate(value)
def to_database(self, value):
return self.validate(value)
class Float(BaseFloat):
"""
Stores a single-precision floating-point value
"""
db_type = 'float'
class Double(BaseFloat):
"""
Stores a double-precision floating-point value
"""
db_type = 'double'
class Decimal(Column):
"""
Stores a variable precision decimal value
"""
db_type = 'decimal'
def validate(self, value):
from decimal import Decimal as _Decimal
from decimal import InvalidOperation
val = super(Decimal, self).validate(value)
if val is None:
return
try:
return _Decimal(repr(val)) if isinstance(val, float) else _Decimal(val)
except InvalidOperation:
raise ValidationError("{0} '{1}' can't be coerced to decimal".format(self.column_name, val))
def to_python(self, value):
return self.validate(value)
def to_database(self, value):
return self.validate(value)
class BaseCollectionColumn(Column):
"""
Base Container type for collection-like columns.
http://cassandra.apache.org/doc/cql3/CQL-3.0.html#collections
"""
def __init__(self, types, **kwargs):
"""
:param types: a sequence of sub types in this collection
"""
instances = []
for t in types:
inheritance_comparator = issubclass if isinstance(t, type) else isinstance
if not inheritance_comparator(t, Column):
raise ValidationError("%s is not a column class" % (t,))
if t.db_type is None:
raise ValidationError("%s is an abstract type" % (t,))
inst = t() if isinstance(t, type) else t
if isinstance(t, BaseCollectionColumn):
inst._freeze_db_type()
instances.append(inst)
self.types = instances
super(BaseCollectionColumn, self).__init__(**kwargs)
def validate(self, value):
value = super(BaseCollectionColumn, self).validate(value)
# It is dangerous to let collections have more than 65535.
# See: https://issues.apache.org/jira/browse/CASSANDRA-5428
if value is not None and len(value) > 65535:
raise ValidationError("{0} Collection can't have more than 65535 elements.".format(self.column_name))
return value
def _val_is_null(self, val):
return not val
def _freeze_db_type(self):
if not self.db_type.startswith('frozen'):
self.db_type = "frozen<%s>" % (self.db_type,)
@property
def sub_types(self):
return self.types
@property
def cql_type(self):
return _cqltypes[self.__class__.__name__.lower()].apply_parameters([c.cql_type for c in self.types])
class Tuple(BaseCollectionColumn):
"""
Stores a fixed-length set of positional values
http://docs.datastax.com/en/cql/3.1/cql/cql_reference/tupleType.html
"""
def __init__(self, *args, **kwargs):
"""
:param args: column types representing tuple composition
"""
if not args:
raise ValueError("Tuple must specify at least one inner type")
super(Tuple, self).__init__(args, **kwargs)
self.db_type = 'tuple<{0}>'.format(', '.join(typ.db_type for typ in self.types))
def validate(self, value):
val = super(Tuple, self).validate(value)
if val is None:
return
if len(val) > len(self.types):
raise ValidationError("Value %r has more fields than tuple definition (%s)" %
(val, ', '.join(t for t in self.types)))
return tuple(t.validate(v) for t, v in zip(self.types, val))
def to_python(self, value):
if value is None:
return tuple()
return tuple(t.to_python(v) for t, v in zip(self.types, value))
def to_database(self, value):
if value is None:
return
return tuple(t.to_database(v) for t, v in zip(self.types, value))
class BaseContainerColumn(BaseCollectionColumn):
pass
class Set(BaseContainerColumn):
"""
Stores a set of unordered, unique values
http://www.datastax.com/documentation/cql/3.1/cql/cql_using/use_set_t.html
"""
_python_type_hashable = False
def __init__(self, value_type, strict=True, default=set, **kwargs):
"""
:param value_type: a column class indicating the types of the value
:param strict: sets whether non set values will be coerced to set
type on validation, or raise a validation error, defaults to True
"""
self.strict = strict
super(Set, self).__init__((value_type,), default=default, **kwargs)
self.value_col = self.types[0]
if not self.value_col._python_type_hashable:
raise ValidationError("Cannot create a Set with unhashable value type (see PYTHON-494)")
self.db_type = 'set<{0}>'.format(self.value_col.db_type)
def validate(self, value):
val = super(Set, self).validate(value)
if val is None:
return
types = (set, util.SortedSet) if self.strict else (set, util.SortedSet, list, tuple)
if not isinstance(val, types):
if self.strict:
raise ValidationError('{0} {1} is not a set object'.format(self.column_name, val))
else:
raise ValidationError('{0} {1} cannot be coerced to a set object'.format(self.column_name, val))
if None in val:
raise ValidationError("{0} None not allowed in a set".format(self.column_name))
# TODO: stop doing this conversion because it doesn't support non-hashable collections as keys (cassandra does)
# will need to start using the cassandra.util types in the next major rev (PYTHON-494)
return set(self.value_col.validate(v) for v in val)
def to_python(self, value):
if value is None:
return set()
return set(self.value_col.to_python(v) for v in value)
def to_database(self, value):
if value is None:
return None
return set(self.value_col.to_database(v) for v in value)
class List(BaseContainerColumn):
"""
Stores a list of ordered values
http://www.datastax.com/documentation/cql/3.1/cql/cql_using/use_list_t.html
"""
_python_type_hashable = False
def __init__(self, value_type, default=list, **kwargs):
"""
:param value_type: a column class indicating the types of the value
"""
super(List, self).__init__((value_type,), default=default, **kwargs)
self.value_col = self.types[0]
self.db_type = 'list<{0}>'.format(self.value_col.db_type)
def validate(self, value):
val = super(List, self).validate(value)
if val is None:
return
if not isinstance(val, (set, list, tuple)):
raise ValidationError('{0} {1} is not a list object'.format(self.column_name, val))
if None in val:
raise ValidationError("{0} None is not allowed in a list".format(self.column_name))
return [self.value_col.validate(v) for v in val]
def to_python(self, value):
if value is None:
return []
return [self.value_col.to_python(v) for v in value]
def to_database(self, value):
if value is None:
return None
return [self.value_col.to_database(v) for v in value]
class Map(BaseContainerColumn):
"""
Stores a key -> value map (dictionary)
https://docs.datastax.com/en/dse/6.7/cql/cql/cql_using/useMap.html
"""
_python_type_hashable = False
def __init__(self, key_type, value_type, default=dict, **kwargs):
"""
:param key_type: a column class indicating the types of the key
:param value_type: a column class indicating the types of the value
"""
super(Map, self).__init__((key_type, value_type), default=default, **kwargs)
self.key_col = self.types[0]
self.value_col = self.types[1]
if not self.key_col._python_type_hashable:
raise ValidationError("Cannot create a Map with unhashable key type (see PYTHON-494)")
self.db_type = 'map<{0}, {1}>'.format(self.key_col.db_type, self.value_col.db_type)
def validate(self, value):
val = super(Map, self).validate(value)
if val is None:
return
if not isinstance(val, (dict, util.OrderedMap)):
raise ValidationError('{0} {1} is not a dict object'.format(self.column_name, val))
if None in val:
raise ValidationError("{0} None is not allowed in a map".format(self.column_name))
# TODO: stop doing this conversion because it doesn't support non-hashable collections as keys (cassandra does)
# will need to start using the cassandra.util types in the next major rev (PYTHON-494)
return dict((self.key_col.validate(k), self.value_col.validate(v)) for k, v in val.items())
def to_python(self, value):
if value is None:
return {}
if value is not None:
return dict((self.key_col.to_python(k), self.value_col.to_python(v)) for k, v in value.items())
def to_database(self, value):
if value is None:
return None
return dict((self.key_col.to_database(k), self.value_col.to_database(v)) for k, v in value.items())
class UDTValueManager(BaseValueManager):
@property
def changed(self):
if self.explicit:
return self.value != self.previous_value
default_value = self.column.get_default()
if not self.column._val_is_null(default_value):
return self.value != default_value
elif self.previous_value is None:
return not self.column._val_is_null(self.value) and self.value.has_changed_fields()
return False
def reset_previous_value(self):
if self.value is not None:
self.value.reset_changed_fields()
self.previous_value = copy(self.value)
class UserDefinedType(Column):
"""
User Defined Type column
http://www.datastax.com/documentation/cql/3.1/cql/cql_using/cqlUseUDT.html
These columns are represented by a specialization of :class:`cassandra.cqlengine.usertype.UserType`.
Please see :ref:`user_types` for examples and discussion.
"""
value_manager = UDTValueManager
def __init__(self, user_type, **kwargs):
"""
:param type user_type: specifies the :class:`~.cqlengine.usertype.UserType` model of the column
"""
self.user_type = user_type
self.db_type = "frozen<%s>" % user_type.type_name()
super(UserDefinedType, self).__init__(**kwargs)
@property
def sub_types(self):
return list(self.user_type._fields.values())
@property
def cql_type(self):
return UserType.make_udt_class(keyspace='', udt_name=self.user_type.type_name(),
field_names=[c.db_field_name for c in self.user_type._fields.values()],
field_types=[c.cql_type for c in self.user_type._fields.values()])
def validate(self, value):
val = super(UserDefinedType, self).validate(value)
if val is None:
return
val.validate()
return val
def to_python(self, value):
if value is None:
return
copied_value = deepcopy(value)
for name, field in self.user_type._fields.items():
if copied_value[name] is not None or isinstance(field, BaseContainerColumn):
copied_value[name] = field.to_python(copied_value[name])
return copied_value
def to_database(self, value):
if value is None:
return
copied_value = deepcopy(value)
for name, field in self.user_type._fields.items():
if copied_value[name] is not None or isinstance(field, BaseContainerColumn):
copied_value[name] = field.to_database(copied_value[name])
return copied_value
def resolve_udts(col_def, out_list):
for col in col_def.sub_types:
resolve_udts(col, out_list)
if isinstance(col_def, UserDefinedType):
out_list.append(col_def.user_type)
class _PartitionKeysToken(Column):
"""
virtual column representing token of partition columns.
Used by filter(pk__token=Token(...)) filters
"""
def __init__(self, model):
self.partition_columns = list(model._partition_keys.values())
super(_PartitionKeysToken, self).__init__(partition_key=True)
@property
def db_field_name(self):
return 'token({0})'.format(', '.join(['"{0}"'.format(c.db_field_name) for c in self.partition_columns]))
|