Current File : /lib/python2.7/site-packages/google/protobuf/internal//type_checkers.py
# Protocol Buffers - Google's data interchange format
# Copyright 2008 Google Inc. All rights reserved.
# https://developers.google.com/protocol-buffers/
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above
# copyright notice, this list of conditions and the following disclaimer
# in the documentation and/or other materials provided with the
# distribution.
# * Neither the name of Google Inc. nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
"""Provides type checking routines.
This module defines type checking utilities in the forms of dictionaries:
VALUE_CHECKERS: A dictionary of field types and a value validation object.
TYPE_TO_BYTE_SIZE_FN: A dictionary with field types and a size computing
function.
TYPE_TO_SERIALIZE_METHOD: A dictionary with field types and serialization
function.
FIELD_TYPE_TO_WIRE_TYPE: A dictionary with field typed and their
coresponding wire types.
TYPE_TO_DESERIALIZE_METHOD: A dictionary with field types and deserialization
function.
"""
__author__ = '[email protected] (Will Robinson)'
import numbers
import six
if six.PY3:
long = int
from google.protobuf.internal import api_implementation
from google.protobuf.internal import decoder
from google.protobuf.internal import encoder
from google.protobuf.internal import wire_format
from google.protobuf import descriptor
_FieldDescriptor = descriptor.FieldDescriptor
def SupportsOpenEnums(field_descriptor):
return field_descriptor.containing_type.syntax == "proto3"
def GetTypeChecker(field):
"""Returns a type checker for a message field of the specified types.
Args:
field: FieldDescriptor object for this field.
Returns:
An instance of TypeChecker which can be used to verify the types
of values assigned to a field of the specified type.
"""
if (field.cpp_type == _FieldDescriptor.CPPTYPE_STRING and
field.type == _FieldDescriptor.TYPE_STRING):
return UnicodeValueChecker()
if field.cpp_type == _FieldDescriptor.CPPTYPE_ENUM:
if SupportsOpenEnums(field):
# When open enums are supported, any int32 can be assigned.
return _VALUE_CHECKERS[_FieldDescriptor.CPPTYPE_INT32]
else:
return EnumValueChecker(field.enum_type)
return _VALUE_CHECKERS[field.cpp_type]
# None of the typecheckers below make any attempt to guard against people
# subclassing builtin types and doing weird things. We're not trying to
# protect against malicious clients here, just people accidentally shooting
# themselves in the foot in obvious ways.
class TypeChecker(object):
"""Type checker used to catch type errors as early as possible
when the client is setting scalar fields in protocol messages.
"""
def __init__(self, *acceptable_types):
self._acceptable_types = acceptable_types
def CheckValue(self, proposed_value):
"""Type check the provided value and return it.
The returned value might have been normalized to another type.
"""
if not isinstance(proposed_value, self._acceptable_types):
message = ('%.1024r has type %s, but expected one of: %s' %
(proposed_value, type(proposed_value), self._acceptable_types))
raise TypeError(message)
return proposed_value
class TypeCheckerWithDefault(TypeChecker):
def __init__(self, default_value, *acceptable_types):
TypeChecker.__init__(self, acceptable_types)
self._default_value = default_value
def DefaultValue(self):
return self._default_value
# IntValueChecker and its subclasses perform integer type-checks
# and bounds-checks.
class IntValueChecker(object):
"""Checker used for integer fields. Performs type-check and range check."""
def CheckValue(self, proposed_value):
if not isinstance(proposed_value, numbers.Integral):
message = ('%.1024r has type %s, but expected one of: %s' %
(proposed_value, type(proposed_value), six.integer_types))
raise TypeError(message)
if not self._MIN <= int(proposed_value) <= self._MAX:
raise ValueError('Value out of range: %d' % proposed_value)
# We force 32-bit values to int and 64-bit values to long to make
# alternate implementations where the distinction is more significant
# (e.g. the C++ implementation) simpler.
proposed_value = self._TYPE(proposed_value)
return proposed_value
def DefaultValue(self):
return 0
class EnumValueChecker(object):
"""Checker used for enum fields. Performs type-check and range check."""
def __init__(self, enum_type):
self._enum_type = enum_type
def CheckValue(self, proposed_value):
if not isinstance(proposed_value, numbers.Integral):
message = ('%.1024r has type %s, but expected one of: %s' %
(proposed_value, type(proposed_value), six.integer_types))
raise TypeError(message)
if int(proposed_value) not in self._enum_type.values_by_number:
raise ValueError('Unknown enum value: %d' % proposed_value)
return proposed_value
def DefaultValue(self):
return self._enum_type.values[0].number
class UnicodeValueChecker(object):
"""Checker used for string fields.
Always returns a unicode value, even if the input is of type str.
"""
def CheckValue(self, proposed_value):
if not isinstance(proposed_value, (bytes, six.text_type)):
message = ('%.1024r has type %s, but expected one of: %s' %
(proposed_value, type(proposed_value), (bytes, six.text_type)))
raise TypeError(message)
# If the value is of type 'bytes' make sure that it is valid UTF-8 data.
if isinstance(proposed_value, bytes):
try:
proposed_value = proposed_value.decode('utf-8')
except UnicodeDecodeError:
raise ValueError('%.1024r has type bytes, but isn\'t valid UTF-8 '
'encoding. Non-UTF-8 strings must be converted to '
'unicode objects before being added.' %
(proposed_value))
return proposed_value
def DefaultValue(self):
return u""
class Int32ValueChecker(IntValueChecker):
# We're sure to use ints instead of longs here since comparison may be more
# efficient.
_MIN = -2147483648
_MAX = 2147483647
_TYPE = int
class Uint32ValueChecker(IntValueChecker):
_MIN = 0
_MAX = (1 << 32) - 1
_TYPE = int
class Int64ValueChecker(IntValueChecker):
_MIN = -(1 << 63)
_MAX = (1 << 63) - 1
_TYPE = long
class Uint64ValueChecker(IntValueChecker):
_MIN = 0
_MAX = (1 << 64) - 1
_TYPE = long
# Type-checkers for all scalar CPPTYPEs.
_VALUE_CHECKERS = {
_FieldDescriptor.CPPTYPE_INT32: Int32ValueChecker(),
_FieldDescriptor.CPPTYPE_INT64: Int64ValueChecker(),
_FieldDescriptor.CPPTYPE_UINT32: Uint32ValueChecker(),
_FieldDescriptor.CPPTYPE_UINT64: Uint64ValueChecker(),
_FieldDescriptor.CPPTYPE_DOUBLE: TypeCheckerWithDefault(
0.0, numbers.Real),
_FieldDescriptor.CPPTYPE_FLOAT: TypeCheckerWithDefault(
0.0, numbers.Real),
_FieldDescriptor.CPPTYPE_BOOL: TypeCheckerWithDefault(
False, bool, numbers.Integral),
_FieldDescriptor.CPPTYPE_STRING: TypeCheckerWithDefault(b'', bytes),
}
# Map from field type to a function F, such that F(field_num, value)
# gives the total byte size for a value of the given type. This
# byte size includes tag information and any other additional space
# associated with serializing "value".
TYPE_TO_BYTE_SIZE_FN = {
_FieldDescriptor.TYPE_DOUBLE: wire_format.DoubleByteSize,
_FieldDescriptor.TYPE_FLOAT: wire_format.FloatByteSize,
_FieldDescriptor.TYPE_INT64: wire_format.Int64ByteSize,
_FieldDescriptor.TYPE_UINT64: wire_format.UInt64ByteSize,
_FieldDescriptor.TYPE_INT32: wire_format.Int32ByteSize,
_FieldDescriptor.TYPE_FIXED64: wire_format.Fixed64ByteSize,
_FieldDescriptor.TYPE_FIXED32: wire_format.Fixed32ByteSize,
_FieldDescriptor.TYPE_BOOL: wire_format.BoolByteSize,
_FieldDescriptor.TYPE_STRING: wire_format.StringByteSize,
_FieldDescriptor.TYPE_GROUP: wire_format.GroupByteSize,
_FieldDescriptor.TYPE_MESSAGE: wire_format.MessageByteSize,
_FieldDescriptor.TYPE_BYTES: wire_format.BytesByteSize,
_FieldDescriptor.TYPE_UINT32: wire_format.UInt32ByteSize,
_FieldDescriptor.TYPE_ENUM: wire_format.EnumByteSize,
_FieldDescriptor.TYPE_SFIXED32: wire_format.SFixed32ByteSize,
_FieldDescriptor.TYPE_SFIXED64: wire_format.SFixed64ByteSize,
_FieldDescriptor.TYPE_SINT32: wire_format.SInt32ByteSize,
_FieldDescriptor.TYPE_SINT64: wire_format.SInt64ByteSize
}
# Maps from field types to encoder constructors.
TYPE_TO_ENCODER = {
_FieldDescriptor.TYPE_DOUBLE: encoder.DoubleEncoder,
_FieldDescriptor.TYPE_FLOAT: encoder.FloatEncoder,
_FieldDescriptor.TYPE_INT64: encoder.Int64Encoder,
_FieldDescriptor.TYPE_UINT64: encoder.UInt64Encoder,
_FieldDescriptor.TYPE_INT32: encoder.Int32Encoder,
_FieldDescriptor.TYPE_FIXED64: encoder.Fixed64Encoder,
_FieldDescriptor.TYPE_FIXED32: encoder.Fixed32Encoder,
_FieldDescriptor.TYPE_BOOL: encoder.BoolEncoder,
_FieldDescriptor.TYPE_STRING: encoder.StringEncoder,
_FieldDescriptor.TYPE_GROUP: encoder.GroupEncoder,
_FieldDescriptor.TYPE_MESSAGE: encoder.MessageEncoder,
_FieldDescriptor.TYPE_BYTES: encoder.BytesEncoder,
_FieldDescriptor.TYPE_UINT32: encoder.UInt32Encoder,
_FieldDescriptor.TYPE_ENUM: encoder.EnumEncoder,
_FieldDescriptor.TYPE_SFIXED32: encoder.SFixed32Encoder,
_FieldDescriptor.TYPE_SFIXED64: encoder.SFixed64Encoder,
_FieldDescriptor.TYPE_SINT32: encoder.SInt32Encoder,
_FieldDescriptor.TYPE_SINT64: encoder.SInt64Encoder,
}
# Maps from field types to sizer constructors.
TYPE_TO_SIZER = {
_FieldDescriptor.TYPE_DOUBLE: encoder.DoubleSizer,
_FieldDescriptor.TYPE_FLOAT: encoder.FloatSizer,
_FieldDescriptor.TYPE_INT64: encoder.Int64Sizer,
_FieldDescriptor.TYPE_UINT64: encoder.UInt64Sizer,
_FieldDescriptor.TYPE_INT32: encoder.Int32Sizer,
_FieldDescriptor.TYPE_FIXED64: encoder.Fixed64Sizer,
_FieldDescriptor.TYPE_FIXED32: encoder.Fixed32Sizer,
_FieldDescriptor.TYPE_BOOL: encoder.BoolSizer,
_FieldDescriptor.TYPE_STRING: encoder.StringSizer,
_FieldDescriptor.TYPE_GROUP: encoder.GroupSizer,
_FieldDescriptor.TYPE_MESSAGE: encoder.MessageSizer,
_FieldDescriptor.TYPE_BYTES: encoder.BytesSizer,
_FieldDescriptor.TYPE_UINT32: encoder.UInt32Sizer,
_FieldDescriptor.TYPE_ENUM: encoder.EnumSizer,
_FieldDescriptor.TYPE_SFIXED32: encoder.SFixed32Sizer,
_FieldDescriptor.TYPE_SFIXED64: encoder.SFixed64Sizer,
_FieldDescriptor.TYPE_SINT32: encoder.SInt32Sizer,
_FieldDescriptor.TYPE_SINT64: encoder.SInt64Sizer,
}
# Maps from field type to a decoder constructor.
TYPE_TO_DECODER = {
_FieldDescriptor.TYPE_DOUBLE: decoder.DoubleDecoder,
_FieldDescriptor.TYPE_FLOAT: decoder.FloatDecoder,
_FieldDescriptor.TYPE_INT64: decoder.Int64Decoder,
_FieldDescriptor.TYPE_UINT64: decoder.UInt64Decoder,
_FieldDescriptor.TYPE_INT32: decoder.Int32Decoder,
_FieldDescriptor.TYPE_FIXED64: decoder.Fixed64Decoder,
_FieldDescriptor.TYPE_FIXED32: decoder.Fixed32Decoder,
_FieldDescriptor.TYPE_BOOL: decoder.BoolDecoder,
_FieldDescriptor.TYPE_STRING: decoder.StringDecoder,
_FieldDescriptor.TYPE_GROUP: decoder.GroupDecoder,
_FieldDescriptor.TYPE_MESSAGE: decoder.MessageDecoder,
_FieldDescriptor.TYPE_BYTES: decoder.BytesDecoder,
_FieldDescriptor.TYPE_UINT32: decoder.UInt32Decoder,
_FieldDescriptor.TYPE_ENUM: decoder.EnumDecoder,
_FieldDescriptor.TYPE_SFIXED32: decoder.SFixed32Decoder,
_FieldDescriptor.TYPE_SFIXED64: decoder.SFixed64Decoder,
_FieldDescriptor.TYPE_SINT32: decoder.SInt32Decoder,
_FieldDescriptor.TYPE_SINT64: decoder.SInt64Decoder,
}
# Maps from field type to expected wiretype.
FIELD_TYPE_TO_WIRE_TYPE = {
_FieldDescriptor.TYPE_DOUBLE: wire_format.WIRETYPE_FIXED64,
_FieldDescriptor.TYPE_FLOAT: wire_format.WIRETYPE_FIXED32,
_FieldDescriptor.TYPE_INT64: wire_format.WIRETYPE_VARINT,
_FieldDescriptor.TYPE_UINT64: wire_format.WIRETYPE_VARINT,
_FieldDescriptor.TYPE_INT32: wire_format.WIRETYPE_VARINT,
_FieldDescriptor.TYPE_FIXED64: wire_format.WIRETYPE_FIXED64,
_FieldDescriptor.TYPE_FIXED32: wire_format.WIRETYPE_FIXED32,
_FieldDescriptor.TYPE_BOOL: wire_format.WIRETYPE_VARINT,
_FieldDescriptor.TYPE_STRING:
wire_format.WIRETYPE_LENGTH_DELIMITED,
_FieldDescriptor.TYPE_GROUP: wire_format.WIRETYPE_START_GROUP,
_FieldDescriptor.TYPE_MESSAGE:
wire_format.WIRETYPE_LENGTH_DELIMITED,
_FieldDescriptor.TYPE_BYTES:
wire_format.WIRETYPE_LENGTH_DELIMITED,
_FieldDescriptor.TYPE_UINT32: wire_format.WIRETYPE_VARINT,
_FieldDescriptor.TYPE_ENUM: wire_format.WIRETYPE_VARINT,
_FieldDescriptor.TYPE_SFIXED32: wire_format.WIRETYPE_FIXED32,
_FieldDescriptor.TYPE_SFIXED64: wire_format.WIRETYPE_FIXED64,
_FieldDescriptor.TYPE_SINT32: wire_format.WIRETYPE_VARINT,
_FieldDescriptor.TYPE_SINT64: wire_format.WIRETYPE_VARINT,
}
