| # 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. |
| |
| """Invocation-side implementation of gRPC Python.""" |
| |
| import sys |
| import threading |
| import time |
| |
| import grpc |
| from grpc import _common |
| from grpc import _grpcio_metadata |
| from grpc.framework.foundation import callable_util |
| from grpc._cython import cygrpc |
| |
| _USER_AGENT = 'Python-gRPC-{}'.format(_grpcio_metadata.__version__) |
| |
| _EMPTY_FLAGS = 0 |
| _INFINITE_FUTURE = cygrpc.Timespec(float('+inf')) |
| _EMPTY_METADATA = cygrpc.Metadata(()) |
| |
| _UNARY_UNARY_INITIAL_DUE = ( |
| cygrpc.OperationType.send_initial_metadata, |
| cygrpc.OperationType.send_message, |
| cygrpc.OperationType.send_close_from_client, |
| cygrpc.OperationType.receive_initial_metadata, |
| cygrpc.OperationType.receive_message, |
| cygrpc.OperationType.receive_status_on_client, |
| ) |
| _UNARY_STREAM_INITIAL_DUE = ( |
| cygrpc.OperationType.send_initial_metadata, |
| cygrpc.OperationType.send_message, |
| cygrpc.OperationType.send_close_from_client, |
| cygrpc.OperationType.receive_initial_metadata, |
| cygrpc.OperationType.receive_status_on_client, |
| ) |
| _STREAM_UNARY_INITIAL_DUE = ( |
| cygrpc.OperationType.send_initial_metadata, |
| cygrpc.OperationType.receive_initial_metadata, |
| cygrpc.OperationType.receive_message, |
| cygrpc.OperationType.receive_status_on_client, |
| ) |
| _STREAM_STREAM_INITIAL_DUE = ( |
| cygrpc.OperationType.send_initial_metadata, |
| cygrpc.OperationType.receive_initial_metadata, |
| cygrpc.OperationType.receive_status_on_client, |
| ) |
| |
| _CHANNEL_SUBSCRIPTION_CALLBACK_ERROR_LOG_MESSAGE = ( |
| 'Exception calling channel subscription callback!') |
| |
| |
| def _deadline(timeout): |
| if timeout is None: |
| return None, _INFINITE_FUTURE |
| else: |
| deadline = time.time() + timeout |
| return deadline, cygrpc.Timespec(deadline) |
| |
| |
| def _unknown_code_details(unknown_cygrpc_code, details): |
| return 'Server sent unknown code {} and details "{}"'.format( |
| unknown_cygrpc_code, details) |
| |
| |
| def _wait_once_until(condition, until): |
| if until is None: |
| condition.wait() |
| else: |
| remaining = until - time.time() |
| if remaining < 0: |
| raise grpc.FutureTimeoutError() |
| else: |
| condition.wait(timeout=remaining) |
| |
| |
| class _RPCState(object): |
| |
| def __init__(self, due, initial_metadata, trailing_metadata, code, details): |
| self.condition = threading.Condition() |
| # The cygrpc.OperationType objects representing events due from the RPC's |
| # completion queue. |
| self.due = set(due) |
| self.initial_metadata = initial_metadata |
| self.response = None |
| self.trailing_metadata = trailing_metadata |
| self.code = code |
| self.details = details |
| # The semantics of grpc.Future.cancel and grpc.Future.cancelled are |
| # slightly wonky, so they have to be tracked separately from the rest of the |
| # result of the RPC. This field tracks whether cancellation was requested |
| # prior to termination of the RPC. |
| self.cancelled = False |
| self.callbacks = [] |
| |
| |
| def _abort(state, code, details): |
| if state.code is None: |
| state.code = code |
| state.details = details |
| if state.initial_metadata is None: |
| state.initial_metadata = _EMPTY_METADATA |
| state.trailing_metadata = _EMPTY_METADATA |
| |
| |
| def _handle_event(event, state, response_deserializer): |
| callbacks = [] |
| for batch_operation in event.batch_operations: |
| operation_type = batch_operation.type |
| state.due.remove(operation_type) |
| if operation_type == cygrpc.OperationType.receive_initial_metadata: |
| state.initial_metadata = batch_operation.received_metadata |
| elif operation_type == cygrpc.OperationType.receive_message: |
| serialized_response = batch_operation.received_message.bytes() |
| if serialized_response is not None: |
| response = _common.deserialize( |
| serialized_response, response_deserializer) |
| if response is None: |
| details = 'Exception deserializing response!' |
| _abort(state, grpc.StatusCode.INTERNAL, details) |
| else: |
| state.response = response |
| elif operation_type == cygrpc.OperationType.receive_status_on_client: |
| state.trailing_metadata = batch_operation.received_metadata |
| if state.code is None: |
| code = _common.CYGRPC_STATUS_CODE_TO_STATUS_CODE.get( |
| batch_operation.received_status_code) |
| if code is None: |
| state.code = grpc.StatusCode.UNKNOWN |
| state.details = _unknown_code_details( |
| batch_operation.received_status_code, |
| batch_operation.received_status_details) |
| else: |
| state.code = code |
| state.details = batch_operation.received_status_details |
| callbacks.extend(state.callbacks) |
| state.callbacks = None |
| return callbacks |
| |
| |
| def _event_handler(state, call, response_deserializer): |
| def handle_event(event): |
| with state.condition: |
| callbacks = _handle_event(event, state, response_deserializer) |
| state.condition.notify_all() |
| done = not state.due |
| for callback in callbacks: |
| callback() |
| return call if done else None |
| return handle_event |
| |
| |
| def _consume_request_iterator( |
| request_iterator, state, call, request_serializer): |
| event_handler = _event_handler(state, call, None) |
| |
| def consume_request_iterator(): |
| for request in request_iterator: |
| serialized_request = _common.serialize(request, request_serializer) |
| with state.condition: |
| if state.code is None and not state.cancelled: |
| if serialized_request is None: |
| call.cancel() |
| details = 'Exception serializing request!' |
| _abort(state, grpc.StatusCode.INTERNAL, details) |
| return |
| else: |
| operations = ( |
| cygrpc.operation_send_message( |
| serialized_request, _EMPTY_FLAGS), |
| ) |
| call.start_client_batch(cygrpc.Operations(operations), |
| event_handler) |
| state.due.add(cygrpc.OperationType.send_message) |
| while True: |
| state.condition.wait() |
| if state.code is None: |
| if cygrpc.OperationType.send_message not in state.due: |
| break |
| else: |
| return |
| else: |
| return |
| with state.condition: |
| if state.code is None: |
| operations = ( |
| cygrpc.operation_send_close_from_client(_EMPTY_FLAGS), |
| ) |
| call.start_client_batch(cygrpc.Operations(operations), event_handler) |
| state.due.add(cygrpc.OperationType.send_close_from_client) |
| |
| def stop_consumption_thread(timeout): |
| with state.condition: |
| if state.code is None: |
| call.cancel() |
| state.cancelled = True |
| _abort(state, grpc.StatusCode.CANCELLED, 'Cancelled!') |
| state.condition.notify_all() |
| |
| consumption_thread = _common.CleanupThread( |
| stop_consumption_thread, target=consume_request_iterator) |
| consumption_thread.start() |
| |
| |
| class _Rendezvous(grpc.RpcError, grpc.Future, grpc.Call): |
| |
| def __init__(self, state, call, response_deserializer, deadline): |
| super(_Rendezvous, self).__init__() |
| self._state = state |
| self._call = call |
| self._response_deserializer = response_deserializer |
| self._deadline = deadline |
| |
| def cancel(self): |
| with self._state.condition: |
| if self._state.code is None: |
| self._call.cancel() |
| self._state.cancelled = True |
| _abort(self._state, grpc.StatusCode.CANCELLED, 'Cancelled!') |
| self._state.condition.notify_all() |
| return False |
| |
| def cancelled(self): |
| with self._state.condition: |
| return self._state.cancelled |
| |
| def running(self): |
| with self._state.condition: |
| return self._state.code is None |
| |
| def done(self): |
| with self._state.condition: |
| return self._state.code is not None |
| |
| def result(self, timeout=None): |
| until = None if timeout is None else time.time() + timeout |
| with self._state.condition: |
| while True: |
| if self._state.code is None: |
| _wait_once_until(self._state.condition, until) |
| elif self._state.code is grpc.StatusCode.OK: |
| return self._state.response |
| elif self._state.cancelled: |
| raise grpc.FutureCancelledError() |
| else: |
| raise self |
| |
| def exception(self, timeout=None): |
| until = None if timeout is None else time.time() + timeout |
| with self._state.condition: |
| while True: |
| if self._state.code is None: |
| _wait_once_until(self._state.condition, until) |
| elif self._state.code is grpc.StatusCode.OK: |
| return None |
| elif self._state.cancelled: |
| raise grpc.FutureCancelledError() |
| else: |
| return self |
| |
| def traceback(self, timeout=None): |
| until = None if timeout is None else time.time() + timeout |
| with self._state.condition: |
| while True: |
| if self._state.code is None: |
| _wait_once_until(self._state.condition, until) |
| elif self._state.code is grpc.StatusCode.OK: |
| return None |
| elif self._state.cancelled: |
| raise grpc.FutureCancelledError() |
| else: |
| try: |
| raise self |
| except grpc.RpcError: |
| return sys.exc_info()[2] |
| |
| def add_done_callback(self, fn): |
| with self._state.condition: |
| if self._state.code is None: |
| self._state.callbacks.append(lambda: fn(self)) |
| return |
| |
| fn(self) |
| |
| def _next(self): |
| with self._state.condition: |
| if self._state.code is None: |
| event_handler = _event_handler( |
| self._state, self._call, self._response_deserializer) |
| self._call.start_client_batch( |
| cygrpc.Operations( |
| (cygrpc.operation_receive_message(_EMPTY_FLAGS),)), |
| event_handler) |
| self._state.due.add(cygrpc.OperationType.receive_message) |
| elif self._state.code is grpc.StatusCode.OK: |
| raise StopIteration() |
| else: |
| raise self |
| while True: |
| self._state.condition.wait() |
| if self._state.response is not None: |
| response = self._state.response |
| self._state.response = None |
| return response |
| elif cygrpc.OperationType.receive_message not in self._state.due: |
| if self._state.code is grpc.StatusCode.OK: |
| raise StopIteration() |
| elif self._state.code is not None: |
| raise self |
| |
| def __iter__(self): |
| return self |
| |
| def __next__(self): |
| return self._next() |
| |
| def next(self): |
| return self._next() |
| |
| def is_active(self): |
| with self._state.condition: |
| return self._state.code is None |
| |
| def time_remaining(self): |
| if self._deadline is None: |
| return None |
| else: |
| return max(self._deadline - time.time(), 0) |
| |
| def add_callback(self, callback): |
| with self._state.condition: |
| if self._state.callbacks is None: |
| return False |
| else: |
| self._state.callbacks.append(lambda: callback()) |
| return True |
| |
| def initial_metadata(self): |
| with self._state.condition: |
| while self._state.initial_metadata is None: |
| self._state.condition.wait() |
| return _common.application_metadata(self._state.initial_metadata) |
| |
| def trailing_metadata(self): |
| with self._state.condition: |
| while self._state.trailing_metadata is None: |
| self._state.condition.wait() |
| return _common.application_metadata(self._state.trailing_metadata) |
| |
| def code(self): |
| with self._state.condition: |
| while self._state.code is None: |
| self._state.condition.wait() |
| return self._state.code |
| |
| def details(self): |
| with self._state.condition: |
| while self._state.details is None: |
| self._state.condition.wait() |
| return _common.decode(self._state.details) |
| |
| def _repr(self): |
| with self._state.condition: |
| if self._state.code is None: |
| return '<_Rendezvous object of in-flight RPC>' |
| else: |
| return '<_Rendezvous of RPC that terminated with ({}, {})>'.format( |
| self._state.code, _common.decode(self._state.details)) |
| |
| def __repr__(self): |
| return self._repr() |
| |
| def __str__(self): |
| return self._repr() |
| |
| def __del__(self): |
| with self._state.condition: |
| if self._state.code is None: |
| self._call.cancel() |
| self._state.cancelled = True |
| self._state.code = grpc.StatusCode.CANCELLED |
| self._state.condition.notify_all() |
| |
| |
| def _start_unary_request(request, timeout, request_serializer): |
| deadline, deadline_timespec = _deadline(timeout) |
| serialized_request = _common.serialize(request, request_serializer) |
| if serialized_request is None: |
| state = _RPCState( |
| (), _EMPTY_METADATA, _EMPTY_METADATA, grpc.StatusCode.INTERNAL, |
| 'Exception serializing request!') |
| rendezvous = _Rendezvous(state, None, None, deadline) |
| return deadline, deadline_timespec, None, rendezvous |
| else: |
| return deadline, deadline_timespec, serialized_request, None |
| |
| |
| def _end_unary_response_blocking(state, with_call, deadline): |
| if state.code is grpc.StatusCode.OK: |
| if with_call: |
| rendezvous = _Rendezvous(state, None, None, deadline) |
| return state.response, rendezvous |
| else: |
| return state.response |
| else: |
| raise _Rendezvous(state, None, None, deadline) |
| |
| |
| class _UnaryUnaryMultiCallable(grpc.UnaryUnaryMultiCallable): |
| |
| def __init__( |
| self, channel, create_managed_call, method, request_serializer, |
| response_deserializer): |
| self._channel = channel |
| self._create_managed_call = create_managed_call |
| self._method = method |
| self._request_serializer = request_serializer |
| self._response_deserializer = response_deserializer |
| |
| def _prepare(self, request, timeout, metadata): |
| deadline, deadline_timespec, serialized_request, rendezvous = ( |
| _start_unary_request(request, timeout, self._request_serializer)) |
| if serialized_request is None: |
| return None, None, None, None, rendezvous |
| else: |
| state = _RPCState(_UNARY_UNARY_INITIAL_DUE, None, None, None, None) |
| operations = ( |
| cygrpc.operation_send_initial_metadata( |
| _common.cygrpc_metadata(metadata), _EMPTY_FLAGS), |
| cygrpc.operation_send_message(serialized_request, _EMPTY_FLAGS), |
| cygrpc.operation_send_close_from_client(_EMPTY_FLAGS), |
| cygrpc.operation_receive_initial_metadata(_EMPTY_FLAGS), |
| cygrpc.operation_receive_message(_EMPTY_FLAGS), |
| cygrpc.operation_receive_status_on_client(_EMPTY_FLAGS), |
| ) |
| return state, operations, deadline, deadline_timespec, None |
| |
| def _blocking(self, request, timeout, metadata, credentials): |
| state, operations, deadline, deadline_timespec, rendezvous = self._prepare( |
| request, timeout, metadata) |
| if rendezvous: |
| raise rendezvous |
| else: |
| completion_queue = cygrpc.CompletionQueue() |
| call = self._channel.create_call( |
| None, 0, completion_queue, self._method, None, deadline_timespec) |
| if credentials is not None: |
| call.set_credentials(credentials._credentials) |
| call.start_client_batch(cygrpc.Operations(operations), None) |
| _handle_event(completion_queue.poll(), state, self._response_deserializer) |
| return state, deadline |
| |
| def __call__(self, request, timeout=None, metadata=None, credentials=None): |
| state, deadline, = self._blocking(request, timeout, metadata, credentials) |
| return _end_unary_response_blocking(state, False, deadline) |
| |
| def with_call(self, request, timeout=None, metadata=None, credentials=None): |
| state, deadline, = self._blocking(request, timeout, metadata, credentials) |
| return _end_unary_response_blocking(state, True, deadline) |
| |
| def future(self, request, timeout=None, metadata=None, credentials=None): |
| state, operations, deadline, deadline_timespec, rendezvous = self._prepare( |
| request, timeout, metadata) |
| if rendezvous: |
| return rendezvous |
| else: |
| call = self._create_managed_call( |
| None, 0, self._method, None, deadline_timespec) |
| if credentials is not None: |
| call.set_credentials(credentials._credentials) |
| event_handler = _event_handler(state, call, self._response_deserializer) |
| with state.condition: |
| call.start_client_batch(cygrpc.Operations(operations), event_handler) |
| return _Rendezvous(state, call, self._response_deserializer, deadline) |
| |
| |
| class _UnaryStreamMultiCallable(grpc.UnaryStreamMultiCallable): |
| |
| def __init__( |
| self, channel, create_managed_call, method, request_serializer, |
| response_deserializer): |
| self._channel = channel |
| self._create_managed_call = create_managed_call |
| self._method = method |
| self._request_serializer = request_serializer |
| self._response_deserializer = response_deserializer |
| |
| def __call__(self, request, timeout=None, metadata=None, credentials=None): |
| deadline, deadline_timespec, serialized_request, rendezvous = ( |
| _start_unary_request(request, timeout, self._request_serializer)) |
| if serialized_request is None: |
| raise rendezvous |
| else: |
| state = _RPCState(_UNARY_STREAM_INITIAL_DUE, None, None, None, None) |
| call = self._create_managed_call( |
| None, 0, self._method, None, deadline_timespec) |
| if credentials is not None: |
| call.set_credentials(credentials._credentials) |
| event_handler = _event_handler(state, call, self._response_deserializer) |
| with state.condition: |
| call.start_client_batch( |
| cygrpc.Operations( |
| (cygrpc.operation_receive_initial_metadata(_EMPTY_FLAGS),)), |
| event_handler) |
| operations = ( |
| cygrpc.operation_send_initial_metadata( |
| _common.cygrpc_metadata(metadata), _EMPTY_FLAGS), |
| cygrpc.operation_send_message(serialized_request, _EMPTY_FLAGS), |
| cygrpc.operation_send_close_from_client(_EMPTY_FLAGS), |
| cygrpc.operation_receive_status_on_client(_EMPTY_FLAGS), |
| ) |
| call.start_client_batch(cygrpc.Operations(operations), event_handler) |
| return _Rendezvous(state, call, self._response_deserializer, deadline) |
| |
| |
| class _StreamUnaryMultiCallable(grpc.StreamUnaryMultiCallable): |
| |
| def __init__( |
| self, channel, create_managed_call, method, request_serializer, |
| response_deserializer): |
| self._channel = channel |
| self._create_managed_call = create_managed_call |
| self._method = method |
| self._request_serializer = request_serializer |
| self._response_deserializer = response_deserializer |
| |
| def _blocking(self, request_iterator, timeout, metadata, credentials): |
| deadline, deadline_timespec = _deadline(timeout) |
| state = _RPCState(_STREAM_UNARY_INITIAL_DUE, None, None, None, None) |
| completion_queue = cygrpc.CompletionQueue() |
| call = self._channel.create_call( |
| None, 0, completion_queue, self._method, None, deadline_timespec) |
| if credentials is not None: |
| call.set_credentials(credentials._credentials) |
| with state.condition: |
| call.start_client_batch( |
| cygrpc.Operations( |
| (cygrpc.operation_receive_initial_metadata(_EMPTY_FLAGS),)), |
| None) |
| operations = ( |
| cygrpc.operation_send_initial_metadata( |
| _common.cygrpc_metadata(metadata), _EMPTY_FLAGS), |
| cygrpc.operation_receive_message(_EMPTY_FLAGS), |
| cygrpc.operation_receive_status_on_client(_EMPTY_FLAGS), |
| ) |
| call.start_client_batch(cygrpc.Operations(operations), None) |
| _consume_request_iterator( |
| request_iterator, state, call, self._request_serializer) |
| while True: |
| event = completion_queue.poll() |
| with state.condition: |
| _handle_event(event, state, self._response_deserializer) |
| state.condition.notify_all() |
| if not state.due: |
| break |
| return state, deadline |
| |
| def __call__( |
| self, request_iterator, timeout=None, metadata=None, credentials=None): |
| state, deadline, = self._blocking( |
| request_iterator, timeout, metadata, credentials) |
| return _end_unary_response_blocking(state, False, deadline) |
| |
| def with_call( |
| self, request_iterator, timeout=None, metadata=None, credentials=None): |
| state, deadline, = self._blocking( |
| request_iterator, timeout, metadata, credentials) |
| return _end_unary_response_blocking(state, True, deadline) |
| |
| def future( |
| self, request_iterator, timeout=None, metadata=None, credentials=None): |
| deadline, deadline_timespec = _deadline(timeout) |
| state = _RPCState(_STREAM_UNARY_INITIAL_DUE, None, None, None, None) |
| call = self._create_managed_call( |
| None, 0, self._method, None, deadline_timespec) |
| if credentials is not None: |
| call.set_credentials(credentials._credentials) |
| event_handler = _event_handler(state, call, self._response_deserializer) |
| with state.condition: |
| call.start_client_batch( |
| cygrpc.Operations( |
| (cygrpc.operation_receive_initial_metadata(_EMPTY_FLAGS),)), |
| event_handler) |
| operations = ( |
| cygrpc.operation_send_initial_metadata( |
| _common.cygrpc_metadata(metadata), _EMPTY_FLAGS), |
| cygrpc.operation_receive_message(_EMPTY_FLAGS), |
| cygrpc.operation_receive_status_on_client(_EMPTY_FLAGS), |
| ) |
| call.start_client_batch(cygrpc.Operations(operations), event_handler) |
| _consume_request_iterator( |
| request_iterator, state, call, self._request_serializer) |
| return _Rendezvous(state, call, self._response_deserializer, deadline) |
| |
| |
| class _StreamStreamMultiCallable(grpc.StreamStreamMultiCallable): |
| |
| def __init__( |
| self, channel, create_managed_call, method, request_serializer, |
| response_deserializer): |
| self._channel = channel |
| self._create_managed_call = create_managed_call |
| self._method = method |
| self._request_serializer = request_serializer |
| self._response_deserializer = response_deserializer |
| |
| def __call__( |
| self, request_iterator, timeout=None, metadata=None, credentials=None): |
| deadline, deadline_timespec = _deadline(timeout) |
| state = _RPCState(_STREAM_STREAM_INITIAL_DUE, None, None, None, None) |
| call = self._create_managed_call( |
| None, 0, self._method, None, deadline_timespec) |
| if credentials is not None: |
| call.set_credentials(credentials._credentials) |
| event_handler = _event_handler(state, call, self._response_deserializer) |
| with state.condition: |
| call.start_client_batch( |
| cygrpc.Operations( |
| (cygrpc.operation_receive_initial_metadata(_EMPTY_FLAGS),)), |
| event_handler) |
| operations = ( |
| cygrpc.operation_send_initial_metadata( |
| _common.cygrpc_metadata(metadata), _EMPTY_FLAGS), |
| cygrpc.operation_receive_status_on_client(_EMPTY_FLAGS), |
| ) |
| call.start_client_batch(cygrpc.Operations(operations), event_handler) |
| _consume_request_iterator( |
| request_iterator, state, call, self._request_serializer) |
| return _Rendezvous(state, call, self._response_deserializer, deadline) |
| |
| |
| class _ChannelCallState(object): |
| |
| def __init__(self, channel): |
| self.lock = threading.Lock() |
| self.channel = channel |
| self.completion_queue = cygrpc.CompletionQueue() |
| self.managed_calls = None |
| |
| |
| def _run_channel_spin_thread(state): |
| def channel_spin(): |
| while True: |
| event = state.completion_queue.poll() |
| completed_call = event.tag(event) |
| if completed_call is not None: |
| with state.lock: |
| state.managed_calls.remove(completed_call) |
| if not state.managed_calls: |
| state.managed_calls = None |
| return |
| |
| def stop_channel_spin(timeout): |
| with state.lock: |
| if state.managed_calls is not None: |
| for call in state.managed_calls: |
| call.cancel() |
| |
| channel_spin_thread = _common.CleanupThread( |
| stop_channel_spin, target=channel_spin) |
| channel_spin_thread.start() |
| |
| |
| def _create_channel_managed_call(state): |
| def create_channel_managed_call(parent, flags, method, host, deadline): |
| """Creates a managed cygrpc.Call. |
| |
| Callers of this function must conduct at least one operation on the returned |
| call. The tags associated with operations conducted on the returned call |
| must be no-argument callables that return None to indicate that this channel |
| should continue polling for events associated with the call and return the |
| call itself to indicate that no more events associated with the call will be |
| generated. |
| |
| Args: |
| parent: A cygrpc.Call to be used as the parent of the created call. |
| flags: An integer bitfield of call flags. |
| method: The RPC method. |
| host: A host string for the created call. |
| deadline: A cygrpc.Timespec to be the deadline of the created call. |
| |
| Returns: |
| A cygrpc.Call with which to conduct an RPC. |
| """ |
| with state.lock: |
| call = state.channel.create_call( |
| parent, flags, state.completion_queue, method, host, deadline) |
| if state.managed_calls is None: |
| state.managed_calls = set((call,)) |
| _run_channel_spin_thread(state) |
| else: |
| state.managed_calls.add(call) |
| return call |
| return create_channel_managed_call |
| |
| |
| class _ChannelConnectivityState(object): |
| |
| def __init__(self, channel): |
| self.lock = threading.Lock() |
| self.channel = channel |
| self.polling = False |
| self.connectivity = None |
| self.try_to_connect = False |
| self.callbacks_and_connectivities = [] |
| self.delivering = False |
| |
| |
| def _deliveries(state): |
| callbacks_needing_update = [] |
| for callback_and_connectivity in state.callbacks_and_connectivities: |
| callback, callback_connectivity, = callback_and_connectivity |
| if callback_connectivity is not state.connectivity: |
| callbacks_needing_update.append(callback) |
| callback_and_connectivity[1] = state.connectivity |
| return callbacks_needing_update |
| |
| |
| def _deliver(state, initial_connectivity, initial_callbacks): |
| connectivity = initial_connectivity |
| callbacks = initial_callbacks |
| while True: |
| for callback in callbacks: |
| callable_util.call_logging_exceptions( |
| callback, _CHANNEL_SUBSCRIPTION_CALLBACK_ERROR_LOG_MESSAGE, |
| connectivity) |
| with state.lock: |
| callbacks = _deliveries(state) |
| if callbacks: |
| connectivity = state.connectivity |
| else: |
| state.delivering = False |
| return |
| |
| |
| def _spawn_delivery(state, callbacks): |
| delivering_thread = threading.Thread( |
| target=_deliver, args=(state, state.connectivity, callbacks,)) |
| delivering_thread.start() |
| state.delivering = True |
| |
| |
| # NOTE(https://github.com/grpc/grpc/issues/3064): We'd rather not poll. |
| def _poll_connectivity(state, channel, initial_try_to_connect): |
| try_to_connect = initial_try_to_connect |
| connectivity = channel.check_connectivity_state(try_to_connect) |
| with state.lock: |
| state.connectivity = ( |
| _common.CYGRPC_CONNECTIVITY_STATE_TO_CHANNEL_CONNECTIVITY[ |
| connectivity]) |
| callbacks = tuple( |
| callback for callback, unused_but_known_to_be_none_connectivity |
| in state.callbacks_and_connectivities) |
| for callback_and_connectivity in state.callbacks_and_connectivities: |
| callback_and_connectivity[1] = state.connectivity |
| if callbacks: |
| _spawn_delivery(state, callbacks) |
| completion_queue = cygrpc.CompletionQueue() |
| while True: |
| channel.watch_connectivity_state( |
| connectivity, cygrpc.Timespec(time.time() + 0.2), |
| completion_queue, None) |
| event = completion_queue.poll() |
| with state.lock: |
| if not state.callbacks_and_connectivities and not state.try_to_connect: |
| state.polling = False |
| state.connectivity = None |
| break |
| try_to_connect = state.try_to_connect |
| state.try_to_connect = False |
| if event.success or try_to_connect: |
| connectivity = channel.check_connectivity_state(try_to_connect) |
| with state.lock: |
| state.connectivity = ( |
| _common.CYGRPC_CONNECTIVITY_STATE_TO_CHANNEL_CONNECTIVITY[ |
| connectivity]) |
| if not state.delivering: |
| callbacks = _deliveries(state) |
| if callbacks: |
| _spawn_delivery(state, callbacks) |
| |
| |
| def _moot(state): |
| with state.lock: |
| del state.callbacks_and_connectivities[:] |
| |
| |
| def _subscribe(state, callback, try_to_connect): |
| with state.lock: |
| if not state.callbacks_and_connectivities and not state.polling: |
| def cancel_all_subscriptions(timeout): |
| _moot(state) |
| polling_thread = _common.CleanupThread( |
| cancel_all_subscriptions, target=_poll_connectivity, |
| args=(state, state.channel, bool(try_to_connect))) |
| polling_thread.start() |
| state.polling = True |
| state.callbacks_and_connectivities.append([callback, None]) |
| elif not state.delivering and state.connectivity is not None: |
| _spawn_delivery(state, (callback,)) |
| state.try_to_connect |= bool(try_to_connect) |
| state.callbacks_and_connectivities.append( |
| [callback, state.connectivity]) |
| else: |
| state.try_to_connect |= bool(try_to_connect) |
| state.callbacks_and_connectivities.append([callback, None]) |
| |
| |
| def _unsubscribe(state, callback): |
| with state.lock: |
| for index, (subscribed_callback, unused_connectivity) in enumerate( |
| state.callbacks_and_connectivities): |
| if callback == subscribed_callback: |
| state.callbacks_and_connectivities.pop(index) |
| break |
| |
| |
| def _options(options): |
| if options is None: |
| pairs = ((cygrpc.ChannelArgKey.primary_user_agent_string, _USER_AGENT),) |
| else: |
| pairs = list(options) + [ |
| (cygrpc.ChannelArgKey.primary_user_agent_string, _USER_AGENT)] |
| encoded_pairs = [ |
| (_common.encode(arg_name), arg_value) if isinstance(arg_value, int) |
| else (_common.encode(arg_name), _common.encode(arg_value)) |
| for arg_name, arg_value in pairs] |
| return cygrpc.ChannelArgs([ |
| cygrpc.ChannelArg(arg_name, arg_value) |
| for arg_name, arg_value in encoded_pairs]) |
| |
| |
| class Channel(grpc.Channel): |
| |
| def __init__(self, target, options, credentials): |
| """Constructor. |
| |
| Args: |
| target: The target to which to connect. |
| options: Configuration options for the channel. |
| credentials: A cygrpc.ChannelCredentials or None. |
| """ |
| self._channel = cygrpc.Channel( |
| _common.encode(target), _options(options), credentials) |
| self._call_state = _ChannelCallState(self._channel) |
| self._connectivity_state = _ChannelConnectivityState(self._channel) |
| |
| def subscribe(self, callback, try_to_connect=None): |
| _subscribe(self._connectivity_state, callback, try_to_connect) |
| |
| def unsubscribe(self, callback): |
| _unsubscribe(self._connectivity_state, callback) |
| |
| def unary_unary( |
| self, method, request_serializer=None, response_deserializer=None): |
| return _UnaryUnaryMultiCallable( |
| self._channel, _create_channel_managed_call(self._call_state), |
| _common.encode(method), request_serializer, response_deserializer) |
| |
| def unary_stream( |
| self, method, request_serializer=None, response_deserializer=None): |
| return _UnaryStreamMultiCallable( |
| self._channel, _create_channel_managed_call(self._call_state), |
| _common.encode(method), request_serializer, response_deserializer) |
| |
| def stream_unary( |
| self, method, request_serializer=None, response_deserializer=None): |
| return _StreamUnaryMultiCallable( |
| self._channel, _create_channel_managed_call(self._call_state), |
| _common.encode(method), request_serializer, response_deserializer) |
| |
| def stream_stream( |
| self, method, request_serializer=None, response_deserializer=None): |
| return _StreamStreamMultiCallable( |
| self._channel, _create_channel_managed_call(self._call_state), |
| _common.encode(method), request_serializer, response_deserializer) |
| |
| def __del__(self): |
| _moot(self._connectivity_state) |