114 lines
4.1 KiB
Python
114 lines
4.1 KiB
Python
# 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.
|
|
|
|
"""Provides a factory class for generating dynamic messages."""
|
|
|
|
__author__ = 'matthewtoia@google.com (Matt Toia)'
|
|
|
|
from google.protobuf import descriptor_database
|
|
from google.protobuf import descriptor_pool
|
|
from google.protobuf import message
|
|
from google.protobuf import reflection
|
|
|
|
|
|
class MessageFactory(object):
|
|
"""Factory for creating Proto2 messages from descriptors in a pool."""
|
|
|
|
def __init__(self):
|
|
"""Initializes a new factory."""
|
|
self._classes = {}
|
|
|
|
def GetPrototype(self, descriptor):
|
|
"""Builds a proto2 message class based on the passed in descriptor.
|
|
|
|
Passing a descriptor with a fully qualified name matching a previous
|
|
invocation will cause the same class to be returned.
|
|
|
|
Args:
|
|
descriptor: The descriptor to build from.
|
|
|
|
Returns:
|
|
A class describing the passed in descriptor.
|
|
"""
|
|
|
|
if descriptor.full_name not in self._classes:
|
|
result_class = reflection.GeneratedProtocolMessageType(
|
|
descriptor.name.encode('ascii', 'ignore'),
|
|
(message.Message,),
|
|
{'DESCRIPTOR': descriptor})
|
|
self._classes[descriptor.full_name] = result_class
|
|
for field in descriptor.fields:
|
|
if field.message_type:
|
|
self.GetPrototype(field.message_type)
|
|
return self._classes[descriptor.full_name]
|
|
|
|
|
|
_DB = descriptor_database.DescriptorDatabase()
|
|
_POOL = descriptor_pool.DescriptorPool(_DB)
|
|
_FACTORY = MessageFactory()
|
|
|
|
|
|
def GetMessages(file_protos):
|
|
"""Builds a dictionary of all the messages available in a set of files.
|
|
|
|
Args:
|
|
file_protos: A sequence of file protos to build messages out of.
|
|
|
|
Returns:
|
|
A dictionary containing all the message types in the files mapping the
|
|
fully qualified name to a Message subclass for the descriptor.
|
|
"""
|
|
|
|
result = {}
|
|
for file_proto in file_protos:
|
|
_DB.Add(file_proto)
|
|
for file_proto in file_protos:
|
|
for desc in _GetAllDescriptors(file_proto.message_type, file_proto.package):
|
|
result[desc.full_name] = _FACTORY.GetPrototype(desc)
|
|
return result
|
|
|
|
|
|
def _GetAllDescriptors(desc_protos, package):
|
|
"""Gets all levels of nested message types as a flattened list of descriptors.
|
|
|
|
Args:
|
|
desc_protos: The descriptor protos to process.
|
|
package: The package where the protos are defined.
|
|
|
|
Yields:
|
|
Each message descriptor for each nested type.
|
|
"""
|
|
|
|
for desc_proto in desc_protos:
|
|
name = '.'.join((package, desc_proto.name))
|
|
yield _POOL.FindMessageTypeByName(name)
|
|
for nested_desc in _GetAllDescriptors(desc_proto.nested_type, name):
|
|
yield nested_desc
|