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−#!/usr/bin/env python
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−#
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−# Copyright 2007 Google Inc.
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−#
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−# Licensed under the Apache License, Version 2.0 (the "License");
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−# you may not use this file except in compliance with the License.
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−# You may obtain a copy of the License at
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−#
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−#     http://www.apache.org/licenses/LICENSE-2.0
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−#
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−# Unless required by applicable law or agreed to in writing, software
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−# distributed under the License is distributed on an "AS IS" BASIS,
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−# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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−# See the License for the specific language governing permissions and
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−# limitations under the License.
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−#
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−
+
−"""Base class for implementing API proxy stubs."""
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−
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−
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−
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−
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−
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−from google.appengine.api import apiproxy_rpc
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−from google.appengine.runtime import apiproxy_errors
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−
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−
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−MAX_REQUEST_SIZE = 1 << 20
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−
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−
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−class APIProxyStub(object):
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−  """Base class for implementing API proxy stub classes.
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−
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−  To implement an API proxy stub:
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−    - Extend this class.
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−    - Override __init__ to pass in appropriate default service name.
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−    - Implement service methods as _Dynamic_<method>(request, response).
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−  """
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−
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−  def __init__(self, service_name, max_request_size=MAX_REQUEST_SIZE):
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−    """Constructor.
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−
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−    Args:
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−      service_name: Service name expected for all calls.
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−      max_request_size: int, maximum allowable size of the incoming request.  A
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−        apiproxy_errors.RequestTooLargeError will be raised if the inbound
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−        request exceeds this size.  Default is 1 MB.
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−    """
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−    self.__service_name = service_name
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−    self.__max_request_size = max_request_size
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−
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−  def CreateRPC(self):
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−    """Creates RPC object instance.
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−
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−    Returns:
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−      a instance of RPC.
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−    """
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−    return apiproxy_rpc.RPC(stub=self)
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−
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−  def MakeSyncCall(self, service, call, request, response):
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−    """The main RPC entry point.
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−
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−    Args:
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−      service: Must be name as provided to service_name of constructor.
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−      call: A string representing the rpc to make.  Must be part of
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−        the underlying services methods and impemented by _Dynamic_<call>.
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−      request: A protocol buffer of the type corresponding to 'call'.
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−      response: A protocol buffer of the type corresponding to 'call'.
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−    """
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−    assert service == self.__service_name, ('Expected "%s" service name, '
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−                                            'was "%s"' % (self.__service_name,
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−                                                          service))
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−    if request.ByteSize() > self.__max_request_size:
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−      raise apiproxy_errors.RequestTooLargeError(
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−          'The request to API call %s.%s() was too large.' % (service, call))
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−    messages = []
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−    assert request.IsInitialized(messages), messages
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−
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−    method = getattr(self, '_Dynamic_' + call)
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−    method(request, response)