Spaces:
Running
Running
File size: 3,825 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 |
# 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.
include "ioutils.pyx"
from cassandra import DriverException
from cassandra.bytesio cimport BytesIOReader
from cassandra.deserializers cimport Deserializer, from_binary
from cassandra.deserializers import find_deserializer
from cassandra.parsing cimport ParseDesc, ColumnParser, RowParser
from cassandra.tuple cimport tuple_new, tuple_set
from cpython.bytes cimport PyBytes_AsStringAndSize
cdef class ListParser(ColumnParser):
"""Decode a ResultMessage into a list of tuples (or other objects)"""
cpdef parse_rows(self, BytesIOReader reader, ParseDesc desc):
cdef Py_ssize_t i, rowcount
rowcount = read_int(reader)
cdef RowParser rowparser = TupleRowParser()
return [rowparser.unpack_row(reader, desc) for i in range(rowcount)]
cdef class LazyParser(ColumnParser):
"""Decode a ResultMessage lazily using a generator"""
cpdef parse_rows(self, BytesIOReader reader, ParseDesc desc):
# Use a little helper function as closures (generators) are not
# supported in cpdef methods
return parse_rows_lazy(reader, desc)
def parse_rows_lazy(BytesIOReader reader, ParseDesc desc):
cdef Py_ssize_t i, rowcount
rowcount = read_int(reader)
cdef RowParser rowparser = TupleRowParser()
return (rowparser.unpack_row(reader, desc) for i in range(rowcount))
cdef class TupleRowParser(RowParser):
"""
Parse a single returned row into a tuple of objects:
(obj1, ..., objN)
"""
cpdef unpack_row(self, BytesIOReader reader, ParseDesc desc):
assert desc.rowsize >= 0
cdef Buffer buf
cdef Buffer newbuf
cdef Py_ssize_t i, rowsize = desc.rowsize
cdef Deserializer deserializer
cdef tuple res = tuple_new(desc.rowsize)
ce_policy = desc.column_encryption_policy
for i in range(rowsize):
# Read the next few bytes
get_buf(reader, &buf)
# Deserialize bytes to python object
deserializer = desc.deserializers[i]
coldesc = desc.coldescs[i]
uses_ce = ce_policy and ce_policy.contains_column(coldesc)
try:
if uses_ce:
col_type = ce_policy.column_type(coldesc)
decrypted_bytes = ce_policy.decrypt(coldesc, to_bytes(&buf))
PyBytes_AsStringAndSize(decrypted_bytes, &newbuf.ptr, &newbuf.size)
deserializer = find_deserializer(ce_policy.column_type(coldesc))
val = from_binary(deserializer, &newbuf, desc.protocol_version)
else:
val = from_binary(deserializer, &buf, desc.protocol_version)
except Exception as e:
raise DriverException('Failed decoding result column "%s" of type %s: %s' % (desc.colnames[i],
desc.coltypes[i].cql_parameterized_type(),
str(e)))
# Insert new object into tuple
tuple_set(res, i, val)
return res
|