Add missing file.

python/google/protobuf/internal/type_checkers.py

@@ -0,0 +1,216 @@
+# Protocol Buffers - Google's data interchange format
+# Copyright 2008 Google Inc.
+# http://code.google.com/p/protobuf/
+#
+# 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.
+
+"""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__ = 'robinson@google.com (Will Robinson)'
+
+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
+
+# 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):
+    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)
+
+
+# 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, (int, long)):
+      message = ('%.1024r has type %s, but expected one of: %s' %
+                 (proposed_value, type(proposed_value), (int, long)))
+      raise TypeError(message)
+    if not self._MIN <= proposed_value <= self._MAX:
+      raise ValueError('Value out of range: %d' % proposed_value)
+
+
+class Int32ValueChecker(IntValueChecker):
+  # We're sure to use ints instead of longs here since comparison may be more
+  # efficient.
+  _MIN = -2147483648
+  _MAX = 2147483647
+
+
+class Uint32ValueChecker(IntValueChecker):
+  _MIN = 0
+  _MAX = (1 << 32) - 1
+
+
+class Int64ValueChecker(IntValueChecker):
+  _MIN = -(1 << 63)
+  _MAX = (1 << 63) - 1
+
+
+class Uint64ValueChecker(IntValueChecker):
+  _MIN = 0
+  _MAX = (1 << 64) - 1
+
+
+# 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: TypeChecker(
+        float, int, long),
+    _FieldDescriptor.CPPTYPE_FLOAT: TypeChecker(
+        float, int, long),
+    _FieldDescriptor.CPPTYPE_BOOL: TypeChecker(bool, int),
+    _FieldDescriptor.CPPTYPE_ENUM: Int32ValueChecker(),
+    _FieldDescriptor.CPPTYPE_STRING: TypeChecker(str),
+    }
+
+
+# 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 type to an unbound Encoder method F, such that
+# F(encoder, field_number, value) will append the serialization
+# of a value of this type to the encoder.
+_Encoder = encoder.Encoder
+TYPE_TO_SERIALIZE_METHOD = {
+    _FieldDescriptor.TYPE_DOUBLE: _Encoder.AppendDouble,
+    _FieldDescriptor.TYPE_FLOAT: _Encoder.AppendFloat,
+    _FieldDescriptor.TYPE_INT64: _Encoder.AppendInt64,
+    _FieldDescriptor.TYPE_UINT64: _Encoder.AppendUInt64,
+    _FieldDescriptor.TYPE_INT32: _Encoder.AppendInt32,
+    _FieldDescriptor.TYPE_FIXED64: _Encoder.AppendFixed64,
+    _FieldDescriptor.TYPE_FIXED32: _Encoder.AppendFixed32,
+    _FieldDescriptor.TYPE_BOOL: _Encoder.AppendBool,
+    _FieldDescriptor.TYPE_STRING: _Encoder.AppendString,
+    _FieldDescriptor.TYPE_GROUP: _Encoder.AppendGroup,
+    _FieldDescriptor.TYPE_MESSAGE: _Encoder.AppendMessage,
+    _FieldDescriptor.TYPE_BYTES: _Encoder.AppendBytes,
+    _FieldDescriptor.TYPE_UINT32: _Encoder.AppendUInt32,
+    _FieldDescriptor.TYPE_ENUM: _Encoder.AppendEnum,
+    _FieldDescriptor.TYPE_SFIXED32: _Encoder.AppendSFixed32,
+    _FieldDescriptor.TYPE_SFIXED64: _Encoder.AppendSFixed64,
+    _FieldDescriptor.TYPE_SINT32: _Encoder.AppendSInt32,
+    _FieldDescriptor.TYPE_SINT64: _Encoder.AppendSInt64,
+    }
+
+
+# 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,
+    }
+
+
+# Maps from field type to an unbound Decoder method F,
+# such that F(decoder) will read a field of the requested type.
+#
+# Note that Message and Group are intentionally missing here.
+# They're handled by _RecursivelyMerge().
+_Decoder = decoder.Decoder
+TYPE_TO_DESERIALIZE_METHOD = {
+    _FieldDescriptor.TYPE_DOUBLE: _Decoder.ReadDouble,
+    _FieldDescriptor.TYPE_FLOAT: _Decoder.ReadFloat,
+    _FieldDescriptor.TYPE_INT64: _Decoder.ReadInt64,
+    _FieldDescriptor.TYPE_UINT64: _Decoder.ReadUInt64,
+    _FieldDescriptor.TYPE_INT32: _Decoder.ReadInt32,
+    _FieldDescriptor.TYPE_FIXED64: _Decoder.ReadFixed64,
+    _FieldDescriptor.TYPE_FIXED32: _Decoder.ReadFixed32,
+    _FieldDescriptor.TYPE_BOOL: _Decoder.ReadBool,
+    _FieldDescriptor.TYPE_STRING: _Decoder.ReadString,
+    _FieldDescriptor.TYPE_BYTES: _Decoder.ReadBytes,
+    _FieldDescriptor.TYPE_UINT32: _Decoder.ReadUInt32,
+    _FieldDescriptor.TYPE_ENUM: _Decoder.ReadEnum,
+    _FieldDescriptor.TYPE_SFIXED32: _Decoder.ReadSFixed32,
+    _FieldDescriptor.TYPE_SFIXED64: _Decoder.ReadSFixed64,
+    _FieldDescriptor.TYPE_SINT32: _Decoder.ReadSInt32,
+    _FieldDescriptor.TYPE_SINT64: _Decoder.ReadSInt64,
+    }