Renamed google.protobuf to protobuf26

third_party/google/protobuf/descriptor.py

-# Protocol Buffers - Google's data interchange format
-# Copyright 2008 Google Inc.  All rights reserved.
-# http://code.google.com/p/protobuf/
-#
-# 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,
-# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-# Needs to stay compatible with Python 2.5 due to GAE.
-#
-# Copyright 2007 Google Inc. All Rights Reserved.
-
-"""Descriptors essentially contain exactly the information found in a .proto
-file, in types that make this information accessible in Python.
-"""
-
-__author__ = 'robinson@google.com (Will Robinson)'
-
-from google.protobuf.internal import api_implementation
-
-
-if api_implementation.Type() == 'cpp':
-  # Used by MakeDescriptor in cpp mode
-  import os
-  import uuid
-
-  if api_implementation.Version() == 2:
-    from google.protobuf.pyext import _message
-  else:
-    from google.protobuf.internal import cpp_message
-
-
-class Error(Exception):
-  """Base error for this module."""
-
-
-class TypeTransformationError(Error):
-  """Error transforming between python proto type and corresponding C++ type."""
-
-
-class DescriptorBase(object):
-
-  """Descriptors base class.
-
-  This class is the base of all descriptor classes. It provides common options
-  related functionaility.
-
-  Attributes:
-    has_options:  True if the descriptor has non-default options.  Usually it
-        is not necessary to read this -- just call GetOptions() which will
-        happily return the default instance.  However, it's sometimes useful
-        for efficiency, and also useful inside the protobuf implementation to
-        avoid some bootstrapping issues.
-  """
-
-  def __init__(self, options, options_class_name):
-    """Initialize the descriptor given its options message and the name of the
-    class of the options message. The name of the class is required in case
-    the options message is None and has to be created.
-    """
-    self._options = options
-    self._options_class_name = options_class_name
-
-    # Does this descriptor have non-default options?
-    self.has_options = options is not None
-
-  def _SetOptions(self, options, options_class_name):
-    """Sets the descriptor's options
-
-    This function is used in generated proto2 files to update descriptor
-    options. It must not be used outside proto2.
-    """
-    self._options = options
-    self._options_class_name = options_class_name
-
-    # Does this descriptor have non-default options?
-    self.has_options = options is not None
-
-  def GetOptions(self):
-    """Retrieves descriptor options.
-
-    This method returns the options set or creates the default options for the
-    descriptor.
-    """
-    if self._options:
-      return self._options
-    from google.protobuf import descriptor_pb2
-    try:
-      options_class = getattr(descriptor_pb2, self._options_class_name)
-    except AttributeError:
-      raise RuntimeError('Unknown options class name %s!' %
-                         (self._options_class_name))
-    self._options = options_class()
-    return self._options
-
-
-class _NestedDescriptorBase(DescriptorBase):
-  """Common class for descriptors that can be nested."""
-
-  def __init__(self, options, options_class_name, name, full_name,
-               file, containing_type, serialized_start=None,
-               serialized_end=None):
-    """Constructor.
-
-    Args:
-      options: Protocol message options or None
-        to use default message options.
-      options_class_name: (str) The class name of the above options.
-
-      name: (str) Name of this protocol message type.
-      full_name: (str) Fully-qualified name of this protocol message type,
-        which will include protocol "package" name and the name of any
-        enclosing types.
-      file: (FileDescriptor) Reference to file info.
-      containing_type: if provided, this is a nested descriptor, with this
-        descriptor as parent, otherwise None.
-      serialized_start: The start index (inclusive) in block in the
-        file.serialized_pb that describes this descriptor.
-      serialized_end: The end index (exclusive) in block in the
-        file.serialized_pb that describes this descriptor.
-    """
-    super(_NestedDescriptorBase, self).__init__(
-        options, options_class_name)
-
-    self.name = name
-    # TODO(falk): Add function to calculate full_name instead of having it in
-    #             memory?
-    self.full_name = full_name
-    self.file = file
-    self.containing_type = containing_type
-
-    self._serialized_start = serialized_start
-    self._serialized_end = serialized_end
-
-  def GetTopLevelContainingType(self):
-    """Returns the root if this is a nested type, or itself if its the root."""
-    desc = self
-    while desc.containing_type is not None:
-      desc = desc.containing_type
-    return desc
-
-  def CopyToProto(self, proto):
-    """Copies this to the matching proto in descriptor_pb2.
-
-    Args:
-      proto: An empty proto instance from descriptor_pb2.
-
-    Raises:
-      Error: If self couldnt be serialized, due to to few constructor arguments.
-    """
-    if (self.file is not None and
-        self._serialized_start is not None and
-        self._serialized_end is not None):
-      proto.ParseFromString(self.file.serialized_pb[
-          self._serialized_start:self._serialized_end])
-    else:
-      raise Error('Descriptor does not contain serialization.')
-
-
-class Descriptor(_NestedDescriptorBase):
-
-  """Descriptor for a protocol message type.
-
-  A Descriptor instance has the following attributes:
-
-    name: (str) Name of this protocol message type.
-    full_name: (str) Fully-qualified name of this protocol message type,
-      which will include protocol "package" name and the name of any
-      enclosing types.
-
-    containing_type: (Descriptor) Reference to the descriptor of the
-      type containing us, or None if this is top-level.
-
-    fields: (list of FieldDescriptors) Field descriptors for all
-      fields in this type.
-    fields_by_number: (dict int -> FieldDescriptor) Same FieldDescriptor
-      objects as in |fields|, but indexed by "number" attribute in each
-      FieldDescriptor.
-    fields_by_name: (dict str -> FieldDescriptor) Same FieldDescriptor
-      objects as in |fields|, but indexed by "name" attribute in each
-      FieldDescriptor.
-
-    nested_types: (list of Descriptors) Descriptor references
-      for all protocol message types nested within this one.
-    nested_types_by_name: (dict str -> Descriptor) Same Descriptor
-      objects as in |nested_types|, but indexed by "name" attribute
-      in each Descriptor.
-
-    enum_types: (list of EnumDescriptors) EnumDescriptor references
-      for all enums contained within this type.
-    enum_types_by_name: (dict str ->EnumDescriptor) Same EnumDescriptor
-      objects as in |enum_types|, but indexed by "name" attribute
-      in each EnumDescriptor.
-    enum_values_by_name: (dict str -> EnumValueDescriptor) Dict mapping
-      from enum value name to EnumValueDescriptor for that value.
-
-    extensions: (list of FieldDescriptor) All extensions defined directly
-      within this message type (NOT within a nested type).
-    extensions_by_name: (dict, string -> FieldDescriptor) Same FieldDescriptor
-      objects as |extensions|, but indexed by "name" attribute of each
-      FieldDescriptor.
-
-    is_extendable:  Does this type define any extension ranges?
-
-    options: (descriptor_pb2.MessageOptions) Protocol message options or None
-      to use default message options.
-
-    oneofs: (list of OneofDescriptor) The list of descriptors for oneof fields
-      in this message.
-    oneofs_by_name: (dict str -> OneofDescriptor) Same objects as in |oneofs|,
-      but indexed by "name" attribute.
-
-    file: (FileDescriptor) Reference to file descriptor.
-  """
-
-  # NOTE(tmarek): The file argument redefining a builtin is nothing we can
-  # fix right now since we don't know how many clients already rely on the
-  # name of the argument.
-  def __init__(self, name, full_name, filename, containing_type, fields,
-               nested_types, enum_types, extensions, options=None,
-               is_extendable=True, extension_ranges=None, oneofs=None,
-               file=None, serialized_start=None, serialized_end=None):  # pylint:disable=redefined-builtin
-    """Arguments to __init__() are as described in the description
-    of Descriptor fields above.
-
-    Note that filename is an obsolete argument, that is not used anymore.
-    Please use file.name to access this as an attribute.
-    """
-    super(Descriptor, self).__init__(
-        options, 'MessageOptions', name, full_name, file,
-        containing_type, serialized_start=serialized_start,
-        serialized_end=serialized_end)
-
-    # We have fields in addition to fields_by_name and fields_by_number,
-    # so that:
-    #   1. Clients can index fields by "order in which they're listed."
-    #   2. Clients can easily iterate over all fields with the terse
-    #      syntax: for f in descriptor.fields: ...
-    self.fields = fields
-    for field in self.fields:
-      field.containing_type = self
-    self.fields_by_number = dict((f.number, f) for f in fields)
-    self.fields_by_name = dict((f.name, f) for f in fields)
-
-    self.nested_types = nested_types
-    for nested_type in nested_types:
-      nested_type.containing_type = self
-    self.nested_types_by_name = dict((t.name, t) for t in nested_types)
-
-    self.enum_types = enum_types
-    for enum_type in self.enum_types:
-      enum_type.containing_type = self
-    self.enum_types_by_name = dict((t.name, t) for t in enum_types)
-    self.enum_values_by_name = dict(
-        (v.name, v) for t in enum_types for v in t.values)
-
-    self.extensions = extensions
-    for extension in self.extensions:
-      extension.extension_scope = self
-    self.extensions_by_name = dict((f.name, f) for f in extensions)
-    self.is_extendable = is_extendable
-    self.extension_ranges = extension_ranges
-    self.oneofs = oneofs if oneofs is not None else []
-    self.oneofs_by_name = dict((o.name, o) for o in self.oneofs)
-    for oneof in self.oneofs:
-      oneof.containing_type = self
-
-  def EnumValueName(self, enum, value):
-    """Returns the string name of an enum value.
-
-    This is just a small helper method to simplify a common operation.
-
-    Args:
-      enum: string name of the Enum.
-      value: int, value of the enum.
-
-    Returns:
-      string name of the enum value.
-
-    Raises:
-      KeyError if either the Enum doesn't exist or the value is not a valid
-        value for the enum.
-    """
-    return self.enum_types_by_name[enum].values_by_number[value].name
-
-  def CopyToProto(self, proto):
-    """Copies this to a descriptor_pb2.DescriptorProto.
-
-    Args:
-      proto: An empty descriptor_pb2.DescriptorProto.
-    """
-    # This function is overriden to give a better doc comment.
-    super(Descriptor, self).CopyToProto(proto)
-
-
-# TODO(robinson): We should have aggressive checking here,
-# for example:
-#   * If you specify a repeated field, you should not be allowed
-#     to specify a default value.
-#   * [Other examples here as needed].
-#
-# TODO(robinson): for this and other *Descriptor classes, we
-# might also want to lock things down aggressively (e.g.,
-# prevent clients from setting the attributes).  Having
-# stronger invariants here in general will reduce the number
-# of runtime checks we must do in reflection.py...
-class FieldDescriptor(DescriptorBase):
-
-  """Descriptor for a single field in a .proto file.
-
-  A FieldDescriptor instance has the following attributes:
-
-    name: (str) Name of this field, exactly as it appears in .proto.
-    full_name: (str) Name of this field, including containing scope.  This is
-      particularly relevant for extensions.
-    index: (int) Dense, 0-indexed index giving the order that this
-      field textually appears within its message in the .proto file.
-    number: (int) Tag number declared for this field in the .proto file.
-
-    type: (One of the TYPE_* constants below) Declared type.
-    cpp_type: (One of the CPPTYPE_* constants below) C++ type used to
-      represent this field.
-
-    label: (One of the LABEL_* constants below) Tells whether this
-      field is optional, required, or repeated.
-    has_default_value: (bool) True if this field has a default value defined,
-      otherwise false.
-    default_value: (Varies) Default value of this field.  Only
-      meaningful for non-repeated scalar fields.  Repeated fields
-      should always set this to [], and non-repeated composite
-      fields should always set this to None.
-
-    containing_type: (Descriptor) Descriptor of the protocol message
-      type that contains this field.  Set by the Descriptor constructor
-      if we're passed into one.
-      Somewhat confusingly, for extension fields, this is the
-      descriptor of the EXTENDED message, not the descriptor
-      of the message containing this field.  (See is_extension and
-      extension_scope below).
-    message_type: (Descriptor) If a composite field, a descriptor
-      of the message type contained in this field.  Otherwise, this is None.
-    enum_type: (EnumDescriptor) If this field contains an enum, a
-      descriptor of that enum.  Otherwise, this is None.
-
-    is_extension: True iff this describes an extension field.
-    extension_scope: (Descriptor) Only meaningful if is_extension is True.
-      Gives the message that immediately contains this extension field.
-      Will be None iff we're a top-level (file-level) extension field.
-
-    options: (descriptor_pb2.FieldOptions) Protocol message field options or
-      None to use default field options.
-
-    containing_oneof: (OneofDescriptor) If the field is a member of a oneof
-      union, contains its descriptor. Otherwise, None.
-  """
-
-  # Must be consistent with C++ FieldDescriptor::Type enum in
-  # descriptor.h.
-  #
-  # TODO(robinson): Find a way to eliminate this repetition.
-  TYPE_DOUBLE         = 1
-  TYPE_FLOAT          = 2
-  TYPE_INT64          = 3
-  TYPE_UINT64         = 4
-  TYPE_INT32          = 5
-  TYPE_FIXED64        = 6
-  TYPE_FIXED32        = 7
-  TYPE_BOOL           = 8
-  TYPE_STRING         = 9
-  TYPE_GROUP          = 10
-  TYPE_MESSAGE        = 11
-  TYPE_BYTES          = 12
-  TYPE_UINT32         = 13
-  TYPE_ENUM           = 14
-  TYPE_SFIXED32       = 15
-  TYPE_SFIXED64       = 16
-  TYPE_SINT32         = 17
-  TYPE_SINT64         = 18
-  MAX_TYPE            = 18
-
-  # Must be consistent with C++ FieldDescriptor::CppType enum in
-  # descriptor.h.
-  #
-  # TODO(robinson): Find a way to eliminate this repetition.
-  CPPTYPE_INT32       = 1
-  CPPTYPE_INT64       = 2
-  CPPTYPE_UINT32      = 3
-  CPPTYPE_UINT64      = 4
-  CPPTYPE_DOUBLE      = 5
-  CPPTYPE_FLOAT       = 6
-  CPPTYPE_BOOL        = 7
-  CPPTYPE_ENUM        = 8
-  CPPTYPE_STRING      = 9
-  CPPTYPE_MESSAGE     = 10
-  MAX_CPPTYPE         = 10
-
-  _PYTHON_TO_CPP_PROTO_TYPE_MAP = {
-      TYPE_DOUBLE: CPPTYPE_DOUBLE,
-      TYPE_FLOAT: CPPTYPE_FLOAT,
-      TYPE_ENUM: CPPTYPE_ENUM,
-      TYPE_INT64: CPPTYPE_INT64,
-      TYPE_SINT64: CPPTYPE_INT64,
-      TYPE_SFIXED64: CPPTYPE_INT64,
-      TYPE_UINT64: CPPTYPE_UINT64,
-      TYPE_FIXED64: CPPTYPE_UINT64,
-      TYPE_INT32: CPPTYPE_INT32,
-      TYPE_SFIXED32: CPPTYPE_INT32,
-      TYPE_SINT32: CPPTYPE_INT32,
-      TYPE_UINT32: CPPTYPE_UINT32,
-      TYPE_FIXED32: CPPTYPE_UINT32,
-      TYPE_BYTES: CPPTYPE_STRING,
-      TYPE_STRING: CPPTYPE_STRING,
-      TYPE_BOOL: CPPTYPE_BOOL,
-      TYPE_MESSAGE: CPPTYPE_MESSAGE,
-      TYPE_GROUP: CPPTYPE_MESSAGE
-      }
-
-  # Must be consistent with C++ FieldDescriptor::Label enum in
-  # descriptor.h.
-  #
-  # TODO(robinson): Find a way to eliminate this repetition.
-  LABEL_OPTIONAL      = 1
-  LABEL_REQUIRED      = 2
-  LABEL_REPEATED      = 3
-  MAX_LABEL           = 3
-
-  # Must be consistent with C++ constants kMaxNumber, kFirstReservedNumber,
-  # and kLastReservedNumber in descriptor.h
-  MAX_FIELD_NUMBER = (1 << 29) - 1
-  FIRST_RESERVED_FIELD_NUMBER = 19000
-  LAST_RESERVED_FIELD_NUMBER = 19999
-
-  def __init__(self, name, full_name, index, number, type, cpp_type, label,
-               default_value, message_type, enum_type, containing_type,
-               is_extension, extension_scope, options=None,
-               has_default_value=True, containing_oneof=None):
-    """The arguments are as described in the description of FieldDescriptor
-    attributes above.
-
-    Note that containing_type may be None, and may be set later if necessary
-    (to deal with circular references between message types, for example).
-    Likewise for extension_scope.
-    """
-    super(FieldDescriptor, self).__init__(options, 'FieldOptions')
-    self.name = name
-    self.full_name = full_name
-    self.index = index
-    self.number = number
-    self.type = type
-    self.cpp_type = cpp_type
-    self.label = label
-    self.has_default_value = has_default_value
-    self.default_value = default_value
-    self.containing_type = containing_type
-    self.message_type = message_type
-    self.enum_type = enum_type
-    self.is_extension = is_extension
-    self.extension_scope = extension_scope
-    self.containing_oneof = containing_oneof
-    if api_implementation.Type() == 'cpp':
-      if is_extension:
-        if api_implementation.Version() == 2:
-          # pylint: disable=protected-access
-          self._cdescriptor = (
-              _message.Message._GetExtensionDescriptor(full_name))
-          # pylint: enable=protected-access
-        else:
-          self._cdescriptor = cpp_message.GetExtensionDescriptor(full_name)
-      else:
-        if api_implementation.Version() == 2:
-          # pylint: disable=protected-access
-          self._cdescriptor = _message.Message._GetFieldDescriptor(full_name)
-          # pylint: enable=protected-access
-        else:
-          self._cdescriptor = cpp_message.GetFieldDescriptor(full_name)
-    else:
-      self._cdescriptor = None
-
-  @staticmethod
-  def ProtoTypeToCppProtoType(proto_type):
-    """Converts from a Python proto type to a C++ Proto Type.
-
-    The Python ProtocolBuffer classes specify both the 'Python' datatype and the
-    'C++' datatype - and they're not the same. This helper method should
-    translate from one to another.
-
-    Args:
-      proto_type: the Python proto type (descriptor.FieldDescriptor.TYPE_*)
-    Returns:
-      descriptor.FieldDescriptor.CPPTYPE_*, the C++ type.
-    Raises:
-      TypeTransformationError: when the Python proto type isn't known.
-    """
-    try:
-      return FieldDescriptor._PYTHON_TO_CPP_PROTO_TYPE_MAP[proto_type]
-    except KeyError:
-      raise TypeTransformationError('Unknown proto_type: %s' % proto_type)
-
-
-class EnumDescriptor(_NestedDescriptorBase):
-
-  """Descriptor for an enum defined in a .proto file.
-
-  An EnumDescriptor instance has the following attributes:
-
-    name: (str) Name of the enum type.
-    full_name: (str) Full name of the type, including package name
-      and any enclosing type(s).
-
-    values: (list of EnumValueDescriptors) List of the values
-      in this enum.
-    values_by_name: (dict str -> EnumValueDescriptor) Same as |values|,
-      but indexed by the "name" field of each EnumValueDescriptor.
-    values_by_number: (dict int -> EnumValueDescriptor) Same as |values|,
-      but indexed by the "number" field of each EnumValueDescriptor.
-    containing_type: (Descriptor) Descriptor of the immediate containing
-      type of this enum, or None if this is an enum defined at the
-      top level in a .proto file.  Set by Descriptor's constructor
-      if we're passed into one.
-    file: (FileDescriptor) Reference to file descriptor.
-    options: (descriptor_pb2.EnumOptions) Enum options message or
-      None to use default enum options.
-  """
-
-  def __init__(self, name, full_name, filename, values,
-               containing_type=None, options=None, file=None,
-               serialized_start=None, serialized_end=None):
-    """Arguments are as described in the attribute description above.
-
-    Note that filename is an obsolete argument, that is not used anymore.
-    Please use file.name to access this as an attribute.
-    """
-    super(EnumDescriptor, self).__init__(
-        options, 'EnumOptions', name, full_name, file,
-        containing_type, serialized_start=serialized_start,
-        serialized_end=serialized_end)
-
-    self.values = values
-    for value in self.values:
-      value.type = self
-    self.values_by_name = dict((v.name, v) for v in values)
-    self.values_by_number = dict((v.number, v) for v in values)
-
-  def CopyToProto(self, proto):
-    """Copies this to a descriptor_pb2.EnumDescriptorProto.
-
-    Args:
-      proto: An empty descriptor_pb2.EnumDescriptorProto.
-    """
-    # This function is overriden to give a better doc comment.
-    super(EnumDescriptor, self).CopyToProto(proto)
-
-
-class EnumValueDescriptor(DescriptorBase):
-
-  """Descriptor for a single value within an enum.
-
-    name: (str) Name of this value.
-    index: (int) Dense, 0-indexed index giving the order that this
-      value appears textually within its enum in the .proto file.
-    number: (int) Actual number assigned to this enum value.
-    type: (EnumDescriptor) EnumDescriptor to which this value
-      belongs.  Set by EnumDescriptor's constructor if we're
-      passed into one.
-    options: (descriptor_pb2.EnumValueOptions) Enum value options message or
-      None to use default enum value options options.
-  """
-
-  def __init__(self, name, index, number, type=None, options=None):
-    """Arguments are as described in the attribute description above."""
-    super(EnumValueDescriptor, self).__init__(options, 'EnumValueOptions')
-    self.name = name
-    self.index = index
-    self.number = number
-    self.type = type
-
-
-class OneofDescriptor(object):
-  """Descriptor for a oneof field.
-
-    name: (str) Name of the oneof field.
-    full_name: (str) Full name of the oneof field, including package name.
-    index: (int) 0-based index giving the order of the oneof field inside
-      its containing type.
-    containing_type: (Descriptor) Descriptor of the protocol message
-      type that contains this field.  Set by the Descriptor constructor
-      if we're passed into one.
-    fields: (list of FieldDescriptor) The list of field descriptors this
-      oneof can contain.
-  """
-
-  def __init__(self, name, full_name, index, containing_type, fields):
-    """Arguments are as described in the attribute description above."""
-    self.name = name
-    self.full_name = full_name
-    self.index = index
-    self.containing_type = containing_type
-    self.fields = fields
-
-
-class ServiceDescriptor(_NestedDescriptorBase):
-
-  """Descriptor for a service.
-
-    name: (str) Name of the service.
-    full_name: (str) Full name of the service, including package name.
-    index: (int) 0-indexed index giving the order that this services
-      definition appears withing the .proto file.
-    methods: (list of MethodDescriptor) List of methods provided by this
-      service.
-    options: (descriptor_pb2.ServiceOptions) Service options message or
-      None to use default service options.
-    file: (FileDescriptor) Reference to file info.
-  """
-
-  def __init__(self, name, full_name, index, methods, options=None, file=None,
-               serialized_start=None, serialized_end=None):
-    super(ServiceDescriptor, self).__init__(
-        options, 'ServiceOptions', name, full_name, file,
-        None, serialized_start=serialized_start,
-        serialized_end=serialized_end)
-    self.index = index
-    self.methods = methods
-    # Set the containing service for each method in this service.
-    for method in self.methods:
-      method.containing_service = self
-
-  def FindMethodByName(self, name):
-    """Searches for the specified method, and returns its descriptor."""
-    for method in self.methods:
-      if name == method.name:
-        return method
-    return None
-
-  def CopyToProto(self, proto):
-    """Copies this to a descriptor_pb2.ServiceDescriptorProto.
-
-    Args:
-      proto: An empty descriptor_pb2.ServiceDescriptorProto.
-    """
-    # This function is overriden to give a better doc comment.
-    super(ServiceDescriptor, self).CopyToProto(proto)
-
-
-class MethodDescriptor(DescriptorBase):
-
-  """Descriptor for a method in a service.
-
-  name: (str) Name of the method within the service.
-  full_name: (str) Full name of method.
-  index: (int) 0-indexed index of the method inside the service.
-  containing_service: (ServiceDescriptor) The service that contains this
-    method.
-  input_type: The descriptor of the message that this method accepts.
-  output_type: The descriptor of the message that this method returns.
-  options: (descriptor_pb2.MethodOptions) Method options message or
-    None to use default method options.
-  """
-
-  def __init__(self, name, full_name, index, containing_service,
-               input_type, output_type, options=None):
-    """The arguments are as described in the description of MethodDescriptor
-    attributes above.
-
-    Note that containing_service may be None, and may be set later if necessary.
-    """
-    super(MethodDescriptor, self).__init__(options, 'MethodOptions')
-    self.name = name
-    self.full_name = full_name
-    self.index = index
-    self.containing_service = containing_service
-    self.input_type = input_type
-    self.output_type = output_type
-
-
-class FileDescriptor(DescriptorBase):
-  """Descriptor for a file. Mimics the descriptor_pb2.FileDescriptorProto.
-
-  Note that enum_types_by_name, extensions_by_name, and dependencies
-  fields are only set by the message_factory module, and not by the
-  generated proto code.
-
-  name: name of file, relative to root of source tree.
-  package: name of the package
-  serialized_pb: (str) Byte string of serialized
-    descriptor_pb2.FileDescriptorProto.
-  dependencies: List of other FileDescriptors this FileDescriptor depends on.
-  message_types_by_name: Dict of message names of their descriptors.
-  enum_types_by_name: Dict of enum names and their descriptors.
-  extensions_by_name: Dict of extension names and their descriptors.
-  """
-
-  def __init__(self, name, package, options=None, serialized_pb=None,
-               dependencies=None):
-    """Constructor."""
-    super(FileDescriptor, self).__init__(options, 'FileOptions')
-
-    self.message_types_by_name = {}
-    self.name = name
-    self.package = package
-    self.serialized_pb = serialized_pb
-
-    self.enum_types_by_name = {}
-    self.extensions_by_name = {}
-    self.dependencies = (dependencies or [])
-
-    if (api_implementation.Type() == 'cpp' and
-        self.serialized_pb is not None):
-      if api_implementation.Version() == 2:
-        # pylint: disable=protected-access
-        _message.Message._BuildFile(self.serialized_pb)
-        # pylint: enable=protected-access
-      else:
-        cpp_message.BuildFile(self.serialized_pb)
-
-  def CopyToProto(self, proto):
-    """Copies this to a descriptor_pb2.FileDescriptorProto.
-
-    Args:
-      proto: An empty descriptor_pb2.FileDescriptorProto.
-    """
-    proto.ParseFromString(self.serialized_pb)
-
-
-def _ParseOptions(message, string):
-  """Parses serialized options.
-
-  This helper function is used to parse serialized options in generated
-  proto2 files. It must not be used outside proto2.
-  """
-  message.ParseFromString(string)
-  return message
-
-
-def MakeDescriptor(desc_proto, package='', build_file_if_cpp=True):
-  """Make a protobuf Descriptor given a DescriptorProto protobuf.
-
-  Handles nested descriptors. Note that this is limited to the scope of defining
-  a message inside of another message. Composite fields can currently only be
-  resolved if the message is defined in the same scope as the field.
-
-  Args:
-    desc_proto: The descriptor_pb2.DescriptorProto protobuf message.
-    package: Optional package name for the new message Descriptor (string).
-    build_file_if_cpp: Update the C++ descriptor pool if api matches.
-                       Set to False on recursion, so no duplicates are created.
-  Returns:
-    A Descriptor for protobuf messages.
-  """
-  if api_implementation.Type() == 'cpp' and build_file_if_cpp:
-    # The C++ implementation requires all descriptors to be backed by the same
-    # definition in the C++ descriptor pool. To do this, we build a
-    # FileDescriptorProto with the same definition as this descriptor and build
-    # it into the pool.
-    from google.protobuf import descriptor_pb2
-    file_descriptor_proto = descriptor_pb2.FileDescriptorProto()
-    file_descriptor_proto.message_type.add().MergeFrom(desc_proto)
-
-    # Generate a random name for this proto file to prevent conflicts with
-    # any imported ones. We need to specify a file name so BuildFile accepts
-    # our FileDescriptorProto, but it is not important what that file name
-    # is actually set to.
-    proto_name = str(uuid.uuid4())
-
-    if package:
-      file_descriptor_proto.name = os.path.join(package.replace('.', '/'),
-                                                proto_name + '.proto')
-      file_descriptor_proto.package = package
-    else:
-      file_descriptor_proto.name = proto_name + '.proto'
-
-    if api_implementation.Version() == 2:
-      # pylint: disable=protected-access
-      _message.Message._BuildFile(file_descriptor_proto.SerializeToString())
-      # pylint: enable=protected-access
-    else:
-      cpp_message.BuildFile(file_descriptor_proto.SerializeToString())
-
-  full_message_name = [desc_proto.name]
-  if package: full_message_name.insert(0, package)
-
-  # Create Descriptors for enum types
-  enum_types = {}
-  for enum_proto in desc_proto.enum_type:
-    full_name = '.'.join(full_message_name + [enum_proto.name])
-    enum_desc = EnumDescriptor(
-      enum_proto.name, full_name, None, [
-          EnumValueDescriptor(enum_val.name, ii, enum_val.number)
-          for ii, enum_val in enumerate(enum_proto.value)])
-    enum_types[full_name] = enum_desc
-
-  # Create Descriptors for nested types
-  nested_types = {}
-  for nested_proto in desc_proto.nested_type:
-    full_name = '.'.join(full_message_name + [nested_proto.name])
-    # Nested types are just those defined inside of the message, not all types
-    # used by fields in the message, so no loops are possible here.
-    nested_desc = MakeDescriptor(nested_proto,
-                                 package='.'.join(full_message_name),
-                                 build_file_if_cpp=False)
-    nested_types[full_name] = nested_desc
-
-  fields = []
-  for field_proto in desc_proto.field:
-    full_name = '.'.join(full_message_name + [field_proto.name])
-    enum_desc = None
-    nested_desc = None
-    if field_proto.HasField('type_name'):
-      type_name = field_proto.type_name
-      full_type_name = '.'.join(full_message_name +
-                                [type_name[type_name.rfind('.')+1:]])
-      if full_type_name in nested_types:
-        nested_desc = nested_types[full_type_name]
-      elif full_type_name in enum_types:
-        enum_desc = enum_types[full_type_name]
-      # Else type_name references a non-local type, which isn't implemented
-    field = FieldDescriptor(
-        field_proto.name, full_name, field_proto.number - 1,
-        field_proto.number, field_proto.type,
-        FieldDescriptor.ProtoTypeToCppProtoType(field_proto.type),
-        field_proto.label, None, nested_desc, enum_desc, None, False, None,
-        has_default_value=False)
-    fields.append(field)
-
-  desc_name = '.'.join(full_message_name)
-  return Descriptor(desc_proto.name, desc_name, None, None, fields,
-                    nested_types.values(), enum_types.values(), [])