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Diffstat (limited to 'src/python/grpcio/grpc/beta/_server_adaptations.py')
-rw-r--r-- | src/python/grpcio/grpc/beta/_server_adaptations.py | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/src/python/grpcio/grpc/beta/_server_adaptations.py b/src/python/grpcio/grpc/beta/_server_adaptations.py new file mode 100644 index 0000000000..1e1f80156a --- /dev/null +++ b/src/python/grpcio/grpc/beta/_server_adaptations.py @@ -0,0 +1,374 @@ +# Copyright 2016, Google Inc. +# All rights reserved. +# +# 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. + +"""Translates gRPC's server-side API into gRPC's server-side Beta API.""" + +import collections +import threading + +import grpc +from grpc import _common +from grpc.beta import interfaces +from grpc.framework.common import cardinality +from grpc.framework.common import style +from grpc.framework.foundation import abandonment +from grpc.framework.foundation import logging_pool +from grpc.framework.foundation import stream +from grpc.framework.interfaces.face import face + +_DEFAULT_POOL_SIZE = 8 + + +class _ServerProtocolContext(interfaces.GRPCServicerContext): + + def __init__(self, servicer_context): + self._servicer_context = servicer_context + + def peer(self): + return self._servicer_context.peer() + + def disable_next_response_compression(self): + pass # TODO(https://github.com/grpc/grpc/issues/4078): design, implement. + + +class _FaceServicerContext(face.ServicerContext): + + def __init__(self, servicer_context): + self._servicer_context = servicer_context + + def is_active(self): + return self._servicer_context.is_active() + + def time_remaining(self): + return self._servicer_context.time_remaining() + + def add_abortion_callback(self, abortion_callback): + raise NotImplementedError( + 'add_abortion_callback no longer supported server-side!') + + def cancel(self): + self._servicer_context.cancel() + + def protocol_context(self): + return _ServerProtocolContext(self._servicer_context) + + def invocation_metadata(self): + return _common.cygrpc_metadata( + self._servicer_context.invocation_metadata()) + + def initial_metadata(self, initial_metadata): + self._servicer_context.send_initial_metadata(initial_metadata) + + def terminal_metadata(self, terminal_metadata): + self._servicer_context.set_terminal_metadata(terminal_metadata) + + def code(self, code): + self._servicer_context.set_code(code) + + def details(self, details): + self._servicer_context.set_details(details) + + +def _adapt_unary_request_inline(unary_request_inline): + def adaptation(request, servicer_context): + return unary_request_inline(request, _FaceServicerContext(servicer_context)) + return adaptation + + +def _adapt_stream_request_inline(stream_request_inline): + def adaptation(request_iterator, servicer_context): + return stream_request_inline( + request_iterator, _FaceServicerContext(servicer_context)) + return adaptation + + +class _Callback(stream.Consumer): + + def __init__(self): + self._condition = threading.Condition() + self._values = [] + self._terminated = False + self._cancelled = False + + def consume(self, value): + with self._condition: + self._values.append(value) + self._condition.notify_all() + + def terminate(self): + with self._condition: + self._terminated = True + self._condition.notify_all() + + def consume_and_terminate(self, value): + with self._condition: + self._values.append(value) + self._terminated = True + self._condition.notify_all() + + def cancel(self): + with self._condition: + self._cancelled = True + self._condition.notify_all() + + def draw_one_value(self): + with self._condition: + while True: + if self._cancelled: + raise abandonment.Abandoned() + elif self._values: + return self._values.pop(0) + elif self._terminated: + return None + else: + self._condition.wait() + + def draw_all_values(self): + with self._condition: + while True: + if self._cancelled: + raise abandonment.Abandoned() + elif self._terminated: + all_values = tuple(self._values) + self._values = None + return all_values + else: + self._condition.wait() + + +def _run_request_pipe_thread(request_iterator, request_consumer, + servicer_context): + thread_joined = threading.Event() + def pipe_requests(): + for request in request_iterator: + if not servicer_context.is_active() or thread_joined.is_set(): + return + request_consumer.consume(request) + if not servicer_context.is_active() or thread_joined.is_set(): + return + request_consumer.terminate() + + def stop_request_pipe(timeout): + thread_joined.set() + + request_pipe_thread = _common.CleanupThread( + stop_request_pipe, target=pipe_requests) + request_pipe_thread.start() + + +def _adapt_unary_unary_event(unary_unary_event): + def adaptation(request, servicer_context): + callback = _Callback() + if not servicer_context.add_callback(callback.cancel): + raise abandonment.Abandoned() + unary_unary_event( + request, callback.consume_and_terminate, + _FaceServicerContext(servicer_context)) + return callback.draw_all_values()[0] + return adaptation + + +def _adapt_unary_stream_event(unary_stream_event): + def adaptation(request, servicer_context): + callback = _Callback() + if not servicer_context.add_callback(callback.cancel): + raise abandonment.Abandoned() + unary_stream_event( + request, callback, _FaceServicerContext(servicer_context)) + while True: + response = callback.draw_one_value() + if response is None: + return + else: + yield response + return adaptation + + +def _adapt_stream_unary_event(stream_unary_event): + def adaptation(request_iterator, servicer_context): + callback = _Callback() + if not servicer_context.add_callback(callback.cancel): + raise abandonment.Abandoned() + request_consumer = stream_unary_event( + callback.consume_and_terminate, _FaceServicerContext(servicer_context)) + _run_request_pipe_thread( + request_iterator, request_consumer, servicer_context) + return callback.draw_all_values()[0] + return adaptation + + +def _adapt_stream_stream_event(stream_stream_event): + def adaptation(request_iterator, servicer_context): + callback = _Callback() + if not servicer_context.add_callback(callback.cancel): + raise abandonment.Abandoned() + request_consumer = stream_stream_event( + callback, _FaceServicerContext(servicer_context)) + _run_request_pipe_thread( + request_iterator, request_consumer, servicer_context) + while True: + response = callback.draw_one_value() + if response is None: + return + else: + yield response + return adaptation + + +class _SimpleMethodHandler( + collections.namedtuple( + '_MethodHandler', + ('request_streaming', 'response_streaming', 'request_deserializer', + 'response_serializer', 'unary_unary', 'unary_stream', 'stream_unary', + 'stream_stream',)), + grpc.RpcMethodHandler): + pass + + +def _simple_method_handler( + implementation, request_deserializer, response_serializer): + if implementation.style is style.Service.INLINE: + if implementation.cardinality is cardinality.Cardinality.UNARY_UNARY: + return _SimpleMethodHandler( + False, False, request_deserializer, response_serializer, + _adapt_unary_request_inline(implementation.unary_unary_inline), None, + None, None) + elif implementation.cardinality is cardinality.Cardinality.UNARY_STREAM: + return _SimpleMethodHandler( + False, True, request_deserializer, response_serializer, None, + _adapt_unary_request_inline(implementation.unary_stream_inline), None, + None) + elif implementation.cardinality is cardinality.Cardinality.STREAM_UNARY: + return _SimpleMethodHandler( + True, False, request_deserializer, response_serializer, None, None, + _adapt_stream_request_inline(implementation.stream_unary_inline), + None) + elif implementation.cardinality is cardinality.Cardinality.STREAM_STREAM: + return _SimpleMethodHandler( + True, True, request_deserializer, response_serializer, None, None, + None, + _adapt_stream_request_inline(implementation.stream_stream_inline)) + elif implementation.style is style.Service.EVENT: + if implementation.cardinality is cardinality.Cardinality.UNARY_UNARY: + return _SimpleMethodHandler( + False, False, request_deserializer, response_serializer, + _adapt_unary_unary_event(implementation.unary_unary_event), None, + None, None) + elif implementation.cardinality is cardinality.Cardinality.UNARY_STREAM: + return _SimpleMethodHandler( + False, True, request_deserializer, response_serializer, None, + _adapt_unary_stream_event(implementation.unary_stream_event), None, + None) + elif implementation.cardinality is cardinality.Cardinality.STREAM_UNARY: + return _SimpleMethodHandler( + True, False, request_deserializer, response_serializer, None, None, + _adapt_stream_unary_event(implementation.stream_unary_event), None) + elif implementation.cardinality is cardinality.Cardinality.STREAM_STREAM: + return _SimpleMethodHandler( + True, True, request_deserializer, response_serializer, None, None, + None, _adapt_stream_stream_event(implementation.stream_stream_event)) + + +def _flatten_method_pair_map(method_pair_map): + method_pair_map = method_pair_map or {} + flat_map = {} + for method_pair in method_pair_map: + method = _common.fully_qualified_method(method_pair[0], method_pair[1]) + flat_map[method] = method_pair_map[method_pair] + return flat_map + + +class _GenericRpcHandler(grpc.GenericRpcHandler): + + def __init__( + self, method_implementations, multi_method_implementation, + request_deserializers, response_serializers): + self._method_implementations = _flatten_method_pair_map( + method_implementations) + self._request_deserializers = _flatten_method_pair_map( + request_deserializers) + self._response_serializers = _flatten_method_pair_map( + response_serializers) + self._multi_method_implementation = multi_method_implementation + + def service(self, handler_call_details): + method_implementation = self._method_implementations.get( + handler_call_details.method) + if method_implementation is not None: + return _simple_method_handler( + method_implementation, + self._request_deserializers.get(handler_call_details.method), + self._response_serializers.get(handler_call_details.method)) + elif self._multi_method_implementation is None: + return None + else: + try: + return None #TODO(nathaniel): call the multimethod. + except face.NoSuchMethodError: + return None + + +class _Server(interfaces.Server): + + def __init__(self, server): + self._server = server + + def add_insecure_port(self, address): + return self._server.add_insecure_port(address) + + def add_secure_port(self, address, server_credentials): + return self._server.add_secure_port(address, server_credentials) + + def start(self): + self._server.start() + + def stop(self, grace): + return self._server.stop(grace) + + def __enter__(self): + self._server.start() + return self + + def __exit__(self, exc_type, exc_val, exc_tb): + self._server.stop(None) + return False + + +def server( + service_implementations, multi_method_implementation, request_deserializers, + response_serializers, thread_pool, thread_pool_size): + generic_rpc_handler = _GenericRpcHandler( + service_implementations, multi_method_implementation, + request_deserializers, response_serializers) + if thread_pool is None: + effective_thread_pool = logging_pool.pool( + _DEFAULT_POOL_SIZE if thread_pool_size is None else thread_pool_size) + else: + effective_thread_pool = thread_pool + return _Server(grpc.server((generic_rpc_handler,), effective_thread_pool)) |