Vehicle-Anti-Theft-Face-Rec.../venv/Lib/site-packages/grpc/_channel.py

1461 lines
57 KiB
Python

# Copyright 2016 gRPC authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Invocation-side implementation of gRPC Python."""
import copy
import functools
import logging
import os
import sys
import threading
import time
import grpc
import grpc.experimental
from grpc import _compression
from grpc import _common
from grpc import _grpcio_metadata
from grpc._cython import cygrpc
_LOGGER = logging.getLogger(__name__)
_USER_AGENT = 'grpc-python/{}'.format(_grpcio_metadata.__version__)
_EMPTY_FLAGS = 0
# NOTE(rbellevi): No guarantees are given about the maintenance of this
# environment variable.
_DEFAULT_SINGLE_THREADED_UNARY_STREAM = os.getenv(
"GRPC_SINGLE_THREADED_UNARY_STREAM") is not None
_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!')
_OK_RENDEZVOUS_REPR_FORMAT = ('<{} of RPC that terminated with:\n'
'\tstatus = {}\n'
'\tdetails = "{}"\n'
'>')
_NON_OK_RENDEZVOUS_REPR_FORMAT = ('<{} of RPC that terminated with:\n'
'\tstatus = {}\n'
'\tdetails = "{}"\n'
'\tdebug_error_string = "{}"\n'
'>')
def _deadline(timeout):
return None if timeout is None else time.time() + timeout
def _unknown_code_details(unknown_cygrpc_code, details):
return 'Server sent unknown code {} and details "{}"'.format(
unknown_cygrpc_code, details)
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
self.debug_error_string = None
# 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 = []
self.fork_epoch = cygrpc.get_fork_epoch()
def reset_postfork_child(self):
self.condition = threading.Condition()
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 = ()
state.trailing_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.initial_metadata()
elif operation_type == cygrpc.OperationType.receive_message:
serialized_response = batch_operation.message()
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.trailing_metadata()
if state.code is None:
code = _common.CYGRPC_STATUS_CODE_TO_STATUS_CODE.get(
batch_operation.code())
if code is None:
state.code = grpc.StatusCode.UNKNOWN
state.details = _unknown_code_details(
code, batch_operation.details())
else:
state.code = code
state.details = batch_operation.details()
state.debug_error_string = batch_operation.error_string()
callbacks.extend(state.callbacks)
state.callbacks = None
return callbacks
def _event_handler(state, 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:
try:
callback()
except Exception as e: # pylint: disable=broad-except
# NOTE(rbellevi): We suppress but log errors here so as not to
# kill the channel spin thread.
logging.error('Exception in callback %s: %s',
repr(callback.func), repr(e))
return done and state.fork_epoch >= cygrpc.get_fork_epoch()
return handle_event
#pylint: disable=too-many-statements
def _consume_request_iterator(request_iterator, state, call, request_serializer,
event_handler):
"""Consume a request iterator supplied by the user."""
def consume_request_iterator(): # pylint: disable=too-many-branches
# Iterate over the request iterator until it is exhausted or an error
# condition is encountered.
while True:
return_from_user_request_generator_invoked = False
try:
# The thread may die in user-code. Do not block fork for this.
cygrpc.enter_user_request_generator()
request = next(request_iterator)
except StopIteration:
break
except Exception: # pylint: disable=broad-except
cygrpc.return_from_user_request_generator()
return_from_user_request_generator_invoked = True
code = grpc.StatusCode.UNKNOWN
details = 'Exception iterating requests!'
_LOGGER.exception(details)
call.cancel(_common.STATUS_CODE_TO_CYGRPC_STATUS_CODE[code],
details)
_abort(state, code, details)
return
finally:
if not return_from_user_request_generator_invoked:
cygrpc.return_from_user_request_generator()
serialized_request = _common.serialize(request, request_serializer)
with state.condition:
if state.code is None and not state.cancelled:
if serialized_request is None:
code = grpc.StatusCode.INTERNAL
details = 'Exception serializing request!'
call.cancel(
_common.STATUS_CODE_TO_CYGRPC_STATUS_CODE[code],
details)
_abort(state, code, details)
return
else:
operations = (cygrpc.SendMessageOperation(
serialized_request, _EMPTY_FLAGS),)
operating = call.operate(operations, event_handler)
if operating:
state.due.add(cygrpc.OperationType.send_message)
else:
return
def _done():
return (state.code is not None or
cygrpc.OperationType.send_message not in
state.due)
_common.wait(state.condition.wait,
_done,
spin_cb=functools.partial(
cygrpc.block_if_fork_in_progress,
state))
if state.code is not None:
return
else:
return
with state.condition:
if state.code is None:
operations = (
cygrpc.SendCloseFromClientOperation(_EMPTY_FLAGS),)
operating = call.operate(operations, event_handler)
if operating:
state.due.add(cygrpc.OperationType.send_close_from_client)
consumption_thread = cygrpc.ForkManagedThread(
target=consume_request_iterator)
consumption_thread.setDaemon(True)
consumption_thread.start()
def _rpc_state_string(class_name, rpc_state):
"""Calculates error string for RPC."""
with rpc_state.condition:
if rpc_state.code is None:
return '<{} object>'.format(class_name)
elif rpc_state.code is grpc.StatusCode.OK:
return _OK_RENDEZVOUS_REPR_FORMAT.format(class_name, rpc_state.code,
rpc_state.details)
else:
return _NON_OK_RENDEZVOUS_REPR_FORMAT.format(
class_name, rpc_state.code, rpc_state.details,
rpc_state.debug_error_string)
class _InactiveRpcError(grpc.RpcError, grpc.Call, grpc.Future):
"""An RPC error not tied to the execution of a particular RPC.
The RPC represented by the state object must not be in-progress or
cancelled.
Attributes:
_state: An instance of _RPCState.
"""
def __init__(self, state):
with state.condition:
self._state = _RPCState((), copy.deepcopy(state.initial_metadata),
copy.deepcopy(state.trailing_metadata),
state.code, copy.deepcopy(state.details))
self._state.response = copy.copy(state.response)
self._state.debug_error_string = copy.copy(state.debug_error_string)
def initial_metadata(self):
return self._state.initial_metadata
def trailing_metadata(self):
return self._state.trailing_metadata
def code(self):
return self._state.code
def details(self):
return _common.decode(self._state.details)
def debug_error_string(self):
return _common.decode(self._state.debug_error_string)
def _repr(self):
return _rpc_state_string(self.__class__.__name__, self._state)
def __repr__(self):
return self._repr()
def __str__(self):
return self._repr()
def cancel(self):
"""See grpc.Future.cancel."""
return False
def cancelled(self):
"""See grpc.Future.cancelled."""
return False
def running(self):
"""See grpc.Future.running."""
return False
def done(self):
"""See grpc.Future.done."""
return True
def result(self, timeout=None): # pylint: disable=unused-argument
"""See grpc.Future.result."""
raise self
def exception(self, timeout=None): # pylint: disable=unused-argument
"""See grpc.Future.exception."""
return self
def traceback(self, timeout=None): # pylint: disable=unused-argument
"""See grpc.Future.traceback."""
try:
raise self
except grpc.RpcError:
return sys.exc_info()[2]
def add_done_callback(self, fn, timeout=None): # pylint: disable=unused-argument
"""See grpc.Future.add_done_callback."""
fn(self)
class _Rendezvous(grpc.RpcError, grpc.RpcContext):
"""An RPC iterator.
Attributes:
_state: An instance of _RPCState.
_call: An instance of SegregatedCall or IntegratedCall.
In either case, the _call object is expected to have operate, cancel,
and next_event methods.
_response_deserializer: A callable taking bytes and return a Python
object.
_deadline: A float representing the deadline of the RPC in seconds. Or
possibly None, to represent an RPC with no deadline at all.
"""
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 is_active(self):
"""See grpc.RpcContext.is_active"""
with self._state.condition:
return self._state.code is None
def time_remaining(self):
"""See grpc.RpcContext.time_remaining"""
with self._state.condition:
if self._deadline is None:
return None
else:
return max(self._deadline - time.time(), 0)
def cancel(self):
"""See grpc.RpcContext.cancel"""
with self._state.condition:
if self._state.code is None:
code = grpc.StatusCode.CANCELLED
details = 'Locally cancelled by application!'
self._call.cancel(
_common.STATUS_CODE_TO_CYGRPC_STATUS_CODE[code], details)
self._state.cancelled = True
_abort(self._state, code, details)
self._state.condition.notify_all()
return True
else:
return False
def add_callback(self, callback):
"""See grpc.RpcContext.add_callback"""
with self._state.condition:
if self._state.callbacks is None:
return False
else:
self._state.callbacks.append(callback)
return True
def __iter__(self):
return self
def next(self):
return self._next()
def __next__(self):
return self._next()
def _next(self):
raise NotImplementedError()
def debug_error_string(self):
raise NotImplementedError()
def _repr(self):
return _rpc_state_string(self.__class__.__name__, self._state)
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._state.code = grpc.StatusCode.CANCELLED
self._state.details = 'Cancelled upon garbage collection!'
self._state.cancelled = True
self._call.cancel(
_common.STATUS_CODE_TO_CYGRPC_STATUS_CODE[self._state.code],
self._state.details)
self._state.condition.notify_all()
class _SingleThreadedRendezvous(_Rendezvous, grpc.Call): # pylint: disable=too-many-ancestors
"""An RPC iterator operating entirely on a single thread.
The __next__ method of _SingleThreadedRendezvous does not depend on the
existence of any other thread, including the "channel spin thread".
However, this means that its interface is entirely synchronous. So this
class cannot fulfill the grpc.Future interface.
"""
def initial_metadata(self):
"""See grpc.Call.initial_metadata"""
with self._state.condition:
# NOTE(gnossen): Based on our initial call batch, we are guaranteed
# to receive initial metadata before any messages.
while self._state.initial_metadata is None:
self._consume_next_event()
return self._state.initial_metadata
def trailing_metadata(self):
"""See grpc.Call.trailing_metadata"""
with self._state.condition:
if self._state.trailing_metadata is None:
raise grpc.experimental.UsageError(
"Cannot get trailing metadata until RPC is completed.")
return self._state.trailing_metadata
def code(self):
"""See grpc.Call.code"""
with self._state.condition:
if self._state.code is None:
raise grpc.experimental.UsageError(
"Cannot get code until RPC is completed.")
return self._state.code
def details(self):
"""See grpc.Call.details"""
with self._state.condition:
if self._state.details is None:
raise grpc.experimental.UsageError(
"Cannot get details until RPC is completed.")
return _common.decode(self._state.details)
def _consume_next_event(self):
event = self._call.next_event()
with self._state.condition:
callbacks = _handle_event(event, self._state,
self._response_deserializer)
for callback in callbacks:
# NOTE(gnossen): We intentionally allow exceptions to bubble up
# to the user when running on a single thread.
callback()
return event
def _next_response(self):
while True:
self._consume_next_event()
with self._state.condition:
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 _next(self):
with self._state.condition:
if self._state.code is None:
operating = self._call.operate(
(cygrpc.ReceiveMessageOperation(_EMPTY_FLAGS),), None)
if operating:
self._state.due.add(cygrpc.OperationType.receive_message)
elif self._state.code is grpc.StatusCode.OK:
raise StopIteration()
else:
raise self
return self._next_response()
def debug_error_string(self):
with self._state.condition:
if self._state.debug_error_string is None:
raise grpc.experimental.UsageError(
"Cannot get debug error string until RPC is completed.")
return _common.decode(self._state.debug_error_string)
class _MultiThreadedRendezvous(_Rendezvous, grpc.Call, grpc.Future): # pylint: disable=too-many-ancestors
"""An RPC iterator that depends on a channel spin thread.
This iterator relies upon a per-channel thread running in the background,
dequeueing events from the completion queue, and notifying threads waiting
on the threading.Condition object in the _RPCState object.
This extra thread allows _MultiThreadedRendezvous to fulfill the grpc.Future interface
and to mediate a bidirection streaming RPC.
"""
def initial_metadata(self):
"""See grpc.Call.initial_metadata"""
with self._state.condition:
def _done():
return self._state.initial_metadata is not None
_common.wait(self._state.condition.wait, _done)
return self._state.initial_metadata
def trailing_metadata(self):
"""See grpc.Call.trailing_metadata"""
with self._state.condition:
def _done():
return self._state.trailing_metadata is not None
_common.wait(self._state.condition.wait, _done)
return self._state.trailing_metadata
def code(self):
"""See grpc.Call.code"""
with self._state.condition:
def _done():
return self._state.code is not None
_common.wait(self._state.condition.wait, _done)
return self._state.code
def details(self):
"""See grpc.Call.details"""
with self._state.condition:
def _done():
return self._state.details is not None
_common.wait(self._state.condition.wait, _done)
return _common.decode(self._state.details)
def debug_error_string(self):
with self._state.condition:
def _done():
return self._state.debug_error_string is not None
_common.wait(self._state.condition.wait, _done)
return _common.decode(self._state.debug_error_string)
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 _is_complete(self):
return self._state.code is not None
def result(self, timeout=None):
"""Returns the result of the computation or raises its exception.
See grpc.Future.result for the full API contract.
"""
with self._state.condition:
timed_out = _common.wait(self._state.condition.wait,
self._is_complete,
timeout=timeout)
if timed_out:
raise grpc.FutureTimeoutError()
else:
if 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):
"""Return the exception raised by the computation.
See grpc.Future.exception for the full API contract.
"""
with self._state.condition:
timed_out = _common.wait(self._state.condition.wait,
self._is_complete,
timeout=timeout)
if timed_out:
raise grpc.FutureTimeoutError()
else:
if self._state.code is grpc.StatusCode.OK:
return None
elif self._state.cancelled:
raise grpc.FutureCancelledError()
else:
return self
def traceback(self, timeout=None):
"""Access the traceback of the exception raised by the computation.
See grpc.future.traceback for the full API contract.
"""
with self._state.condition:
timed_out = _common.wait(self._state.condition.wait,
self._is_complete,
timeout=timeout)
if timed_out:
raise grpc.FutureTimeoutError()
else:
if 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(functools.partial(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._response_deserializer)
operating = self._call.operate(
(cygrpc.ReceiveMessageOperation(_EMPTY_FLAGS),),
event_handler)
if operating:
self._state.due.add(cygrpc.OperationType.receive_message)
elif self._state.code is grpc.StatusCode.OK:
raise StopIteration()
else:
raise self
def _response_ready():
return (
self._state.response is not None or
(cygrpc.OperationType.receive_message not in self._state.due
and self._state.code is not None))
_common.wait(self._state.condition.wait, _response_ready)
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 _start_unary_request(request, timeout, request_serializer):
deadline = _deadline(timeout)
serialized_request = _common.serialize(request, request_serializer)
if serialized_request is None:
state = _RPCState((), (), (), grpc.StatusCode.INTERNAL,
'Exception serializing request!')
error = _InactiveRpcError(state)
return deadline, None, error
else:
return deadline, serialized_request, None
def _end_unary_response_blocking(state, call, with_call, deadline):
if state.code is grpc.StatusCode.OK:
if with_call:
rendezvous = _MultiThreadedRendezvous(state, call, None, deadline)
return state.response, rendezvous
else:
return state.response
else:
raise _InactiveRpcError(state)
def _stream_unary_invocation_operationses(metadata, initial_metadata_flags):
return (
(
cygrpc.SendInitialMetadataOperation(metadata,
initial_metadata_flags),
cygrpc.ReceiveMessageOperation(_EMPTY_FLAGS),
cygrpc.ReceiveStatusOnClientOperation(_EMPTY_FLAGS),
),
(cygrpc.ReceiveInitialMetadataOperation(_EMPTY_FLAGS),),
)
def _stream_unary_invocation_operationses_and_tags(metadata,
initial_metadata_flags):
return tuple((
operations,
None,
) for operations in _stream_unary_invocation_operationses(
metadata, initial_metadata_flags))
def _determine_deadline(user_deadline):
parent_deadline = cygrpc.get_deadline_from_context()
if parent_deadline is None and user_deadline is None:
return None
elif parent_deadline is not None and user_deadline is None:
return parent_deadline
elif user_deadline is not None and parent_deadline is None:
return user_deadline
else:
return min(parent_deadline, user_deadline)
class _UnaryUnaryMultiCallable(grpc.UnaryUnaryMultiCallable):
# pylint: disable=too-many-arguments
def __init__(self, channel, managed_call, method, request_serializer,
response_deserializer):
self._channel = channel
self._managed_call = managed_call
self._method = method
self._request_serializer = request_serializer
self._response_deserializer = response_deserializer
self._context = cygrpc.build_census_context()
def _prepare(self, request, timeout, metadata, wait_for_ready, compression):
deadline, serialized_request, rendezvous = _start_unary_request(
request, timeout, self._request_serializer)
initial_metadata_flags = _InitialMetadataFlags().with_wait_for_ready(
wait_for_ready)
augmented_metadata = _compression.augment_metadata(
metadata, compression)
if serialized_request is None:
return None, None, None, rendezvous
else:
state = _RPCState(_UNARY_UNARY_INITIAL_DUE, None, None, None, None)
operations = (
cygrpc.SendInitialMetadataOperation(augmented_metadata,
initial_metadata_flags),
cygrpc.SendMessageOperation(serialized_request, _EMPTY_FLAGS),
cygrpc.SendCloseFromClientOperation(_EMPTY_FLAGS),
cygrpc.ReceiveInitialMetadataOperation(_EMPTY_FLAGS),
cygrpc.ReceiveMessageOperation(_EMPTY_FLAGS),
cygrpc.ReceiveStatusOnClientOperation(_EMPTY_FLAGS),
)
return state, operations, deadline, None
def _blocking(self, request, timeout, metadata, credentials, wait_for_ready,
compression):
state, operations, deadline, rendezvous = self._prepare(
request, timeout, metadata, wait_for_ready, compression)
if state is None:
raise rendezvous # pylint: disable-msg=raising-bad-type
else:
call = self._channel.segregated_call(
cygrpc.PropagationConstants.GRPC_PROPAGATE_DEFAULTS,
self._method, None, _determine_deadline(deadline), metadata,
None if credentials is None else credentials._credentials, ((
operations,
None,
),), self._context)
event = call.next_event()
_handle_event(event, state, self._response_deserializer)
return state, call
def __call__(self,
request,
timeout=None,
metadata=None,
credentials=None,
wait_for_ready=None,
compression=None):
state, call, = self._blocking(request, timeout, metadata, credentials,
wait_for_ready, compression)
return _end_unary_response_blocking(state, call, False, None)
def with_call(self,
request,
timeout=None,
metadata=None,
credentials=None,
wait_for_ready=None,
compression=None):
state, call, = self._blocking(request, timeout, metadata, credentials,
wait_for_ready, compression)
return _end_unary_response_blocking(state, call, True, None)
def future(self,
request,
timeout=None,
metadata=None,
credentials=None,
wait_for_ready=None,
compression=None):
state, operations, deadline, rendezvous = self._prepare(
request, timeout, metadata, wait_for_ready, compression)
if state is None:
raise rendezvous # pylint: disable-msg=raising-bad-type
else:
event_handler = _event_handler(state, self._response_deserializer)
call = self._managed_call(
cygrpc.PropagationConstants.GRPC_PROPAGATE_DEFAULTS,
self._method, None, deadline, metadata,
None if credentials is None else credentials._credentials,
(operations,), event_handler, self._context)
return _MultiThreadedRendezvous(state, call,
self._response_deserializer,
deadline)
class _SingleThreadedUnaryStreamMultiCallable(grpc.UnaryStreamMultiCallable):
# pylint: disable=too-many-arguments
def __init__(self, channel, method, request_serializer,
response_deserializer):
self._channel = channel
self._method = method
self._request_serializer = request_serializer
self._response_deserializer = response_deserializer
self._context = cygrpc.build_census_context()
def __call__( # pylint: disable=too-many-locals
self,
request,
timeout=None,
metadata=None,
credentials=None,
wait_for_ready=None,
compression=None):
deadline = _deadline(timeout)
serialized_request = _common.serialize(request,
self._request_serializer)
if serialized_request is None:
state = _RPCState((), (), (), grpc.StatusCode.INTERNAL,
'Exception serializing request!')
raise _InactiveRpcError(state)
state = _RPCState(_UNARY_STREAM_INITIAL_DUE, None, None, None, None)
call_credentials = None if credentials is None else credentials._credentials
initial_metadata_flags = _InitialMetadataFlags().with_wait_for_ready(
wait_for_ready)
augmented_metadata = _compression.augment_metadata(
metadata, compression)
operations = (
(cygrpc.SendInitialMetadataOperation(augmented_metadata,
initial_metadata_flags),
cygrpc.SendMessageOperation(serialized_request, _EMPTY_FLAGS),
cygrpc.SendCloseFromClientOperation(_EMPTY_FLAGS)),
(cygrpc.ReceiveStatusOnClientOperation(_EMPTY_FLAGS),),
(cygrpc.ReceiveInitialMetadataOperation(_EMPTY_FLAGS),),
)
operations_and_tags = tuple((ops, None) for ops in operations)
call = self._channel.segregated_call(
cygrpc.PropagationConstants.GRPC_PROPAGATE_DEFAULTS, self._method,
None, _determine_deadline(deadline), metadata, call_credentials,
operations_and_tags, self._context)
return _SingleThreadedRendezvous(state, call,
self._response_deserializer, deadline)
class _UnaryStreamMultiCallable(grpc.UnaryStreamMultiCallable):
# pylint: disable=too-many-arguments
def __init__(self, channel, managed_call, method, request_serializer,
response_deserializer):
self._channel = channel
self._managed_call = managed_call
self._method = method
self._request_serializer = request_serializer
self._response_deserializer = response_deserializer
self._context = cygrpc.build_census_context()
def __call__( # pylint: disable=too-many-locals
self,
request,
timeout=None,
metadata=None,
credentials=None,
wait_for_ready=None,
compression=None):
deadline, serialized_request, rendezvous = _start_unary_request(
request, timeout, self._request_serializer)
initial_metadata_flags = _InitialMetadataFlags().with_wait_for_ready(
wait_for_ready)
if serialized_request is None:
raise rendezvous # pylint: disable-msg=raising-bad-type
else:
augmented_metadata = _compression.augment_metadata(
metadata, compression)
state = _RPCState(_UNARY_STREAM_INITIAL_DUE, None, None, None, None)
operationses = (
(
cygrpc.SendInitialMetadataOperation(augmented_metadata,
initial_metadata_flags),
cygrpc.SendMessageOperation(serialized_request,
_EMPTY_FLAGS),
cygrpc.SendCloseFromClientOperation(_EMPTY_FLAGS),
cygrpc.ReceiveStatusOnClientOperation(_EMPTY_FLAGS),
),
(cygrpc.ReceiveInitialMetadataOperation(_EMPTY_FLAGS),),
)
call = self._managed_call(
cygrpc.PropagationConstants.GRPC_PROPAGATE_DEFAULTS,
self._method, None, _determine_deadline(deadline), metadata,
None if credentials is None else credentials._credentials,
operationses, _event_handler(state,
self._response_deserializer),
self._context)
return _MultiThreadedRendezvous(state, call,
self._response_deserializer,
deadline)
class _StreamUnaryMultiCallable(grpc.StreamUnaryMultiCallable):
# pylint: disable=too-many-arguments
def __init__(self, channel, managed_call, method, request_serializer,
response_deserializer):
self._channel = channel
self._managed_call = managed_call
self._method = method
self._request_serializer = request_serializer
self._response_deserializer = response_deserializer
self._context = cygrpc.build_census_context()
def _blocking(self, request_iterator, timeout, metadata, credentials,
wait_for_ready, compression):
deadline = _deadline(timeout)
state = _RPCState(_STREAM_UNARY_INITIAL_DUE, None, None, None, None)
initial_metadata_flags = _InitialMetadataFlags().with_wait_for_ready(
wait_for_ready)
augmented_metadata = _compression.augment_metadata(
metadata, compression)
call = self._channel.segregated_call(
cygrpc.PropagationConstants.GRPC_PROPAGATE_DEFAULTS, self._method,
None, _determine_deadline(deadline), augmented_metadata,
None if credentials is None else credentials._credentials,
_stream_unary_invocation_operationses_and_tags(
augmented_metadata, initial_metadata_flags), self._context)
_consume_request_iterator(request_iterator, state, call,
self._request_serializer, None)
while True:
event = call.next_event()
with state.condition:
_handle_event(event, state, self._response_deserializer)
state.condition.notify_all()
if not state.due:
break
return state, call
def __call__(self,
request_iterator,
timeout=None,
metadata=None,
credentials=None,
wait_for_ready=None,
compression=None):
state, call, = self._blocking(request_iterator, timeout, metadata,
credentials, wait_for_ready, compression)
return _end_unary_response_blocking(state, call, False, None)
def with_call(self,
request_iterator,
timeout=None,
metadata=None,
credentials=None,
wait_for_ready=None,
compression=None):
state, call, = self._blocking(request_iterator, timeout, metadata,
credentials, wait_for_ready, compression)
return _end_unary_response_blocking(state, call, True, None)
def future(self,
request_iterator,
timeout=None,
metadata=None,
credentials=None,
wait_for_ready=None,
compression=None):
deadline = _deadline(timeout)
state = _RPCState(_STREAM_UNARY_INITIAL_DUE, None, None, None, None)
event_handler = _event_handler(state, self._response_deserializer)
initial_metadata_flags = _InitialMetadataFlags().with_wait_for_ready(
wait_for_ready)
augmented_metadata = _compression.augment_metadata(
metadata, compression)
call = self._managed_call(
cygrpc.PropagationConstants.GRPC_PROPAGATE_DEFAULTS, self._method,
None, deadline, augmented_metadata,
None if credentials is None else credentials._credentials,
_stream_unary_invocation_operationses(metadata,
initial_metadata_flags),
event_handler, self._context)
_consume_request_iterator(request_iterator, state, call,
self._request_serializer, event_handler)
return _MultiThreadedRendezvous(state, call,
self._response_deserializer, deadline)
class _StreamStreamMultiCallable(grpc.StreamStreamMultiCallable):
# pylint: disable=too-many-arguments
def __init__(self, channel, managed_call, method, request_serializer,
response_deserializer):
self._channel = channel
self._managed_call = managed_call
self._method = method
self._request_serializer = request_serializer
self._response_deserializer = response_deserializer
self._context = cygrpc.build_census_context()
def __call__(self,
request_iterator,
timeout=None,
metadata=None,
credentials=None,
wait_for_ready=None,
compression=None):
deadline = _deadline(timeout)
state = _RPCState(_STREAM_STREAM_INITIAL_DUE, None, None, None, None)
initial_metadata_flags = _InitialMetadataFlags().with_wait_for_ready(
wait_for_ready)
augmented_metadata = _compression.augment_metadata(
metadata, compression)
operationses = (
(
cygrpc.SendInitialMetadataOperation(augmented_metadata,
initial_metadata_flags),
cygrpc.ReceiveStatusOnClientOperation(_EMPTY_FLAGS),
),
(cygrpc.ReceiveInitialMetadataOperation(_EMPTY_FLAGS),),
)
event_handler = _event_handler(state, self._response_deserializer)
call = self._managed_call(
cygrpc.PropagationConstants.GRPC_PROPAGATE_DEFAULTS, self._method,
None, _determine_deadline(deadline), augmented_metadata,
None if credentials is None else credentials._credentials,
operationses, event_handler, self._context)
_consume_request_iterator(request_iterator, state, call,
self._request_serializer, event_handler)
return _MultiThreadedRendezvous(state, call,
self._response_deserializer, deadline)
class _InitialMetadataFlags(int):
"""Stores immutable initial metadata flags"""
def __new__(cls, value=_EMPTY_FLAGS):
value &= cygrpc.InitialMetadataFlags.used_mask
return super(_InitialMetadataFlags, cls).__new__(cls, value)
def with_wait_for_ready(self, wait_for_ready):
if wait_for_ready is not None:
if wait_for_ready:
return self.__class__(self | cygrpc.InitialMetadataFlags.wait_for_ready | \
cygrpc.InitialMetadataFlags.wait_for_ready_explicitly_set)
elif not wait_for_ready:
return self.__class__(self & ~cygrpc.InitialMetadataFlags.wait_for_ready | \
cygrpc.InitialMetadataFlags.wait_for_ready_explicitly_set)
return self
class _ChannelCallState(object):
def __init__(self, channel):
self.lock = threading.Lock()
self.channel = channel
self.managed_calls = 0
self.threading = False
def reset_postfork_child(self):
self.managed_calls = 0
def __del__(self):
try:
self.channel.close(cygrpc.StatusCode.cancelled,
'Channel deallocated!')
except (TypeError, AttributeError):
pass
def _run_channel_spin_thread(state):
def channel_spin():
while True:
cygrpc.block_if_fork_in_progress(state)
event = state.channel.next_call_event()
if event.completion_type == cygrpc.CompletionType.queue_timeout:
continue
call_completed = event.tag(event)
if call_completed:
with state.lock:
state.managed_calls -= 1
if state.managed_calls == 0:
return
channel_spin_thread = cygrpc.ForkManagedThread(target=channel_spin)
channel_spin_thread.setDaemon(True)
channel_spin_thread.start()
def _channel_managed_call_management(state):
# pylint: disable=too-many-arguments
def create(flags, method, host, deadline, metadata, credentials,
operationses, event_handler, context):
"""Creates a cygrpc.IntegratedCall.
Args:
flags: An integer bitfield of call flags.
method: The RPC method.
host: A host string for the created call.
deadline: A float to be the deadline of the created call or None if
the call is to have an infinite deadline.
metadata: The metadata for the call or None.
credentials: A cygrpc.CallCredentials or None.
operationses: An iterable of iterables of cygrpc.Operations to be
started on the call.
event_handler: A behavior to call to handle the events resultant from
the operations on the call.
context: Context object for distributed tracing.
Returns:
A cygrpc.IntegratedCall with which to conduct an RPC.
"""
operationses_and_tags = tuple((
operations,
event_handler,
) for operations in operationses)
with state.lock:
call = state.channel.integrated_call(flags, method, host, deadline,
metadata, credentials,
operationses_and_tags, context)
if state.managed_calls == 0:
state.managed_calls = 1
_run_channel_spin_thread(state)
else:
state.managed_calls += 1
return call
return create
class _ChannelConnectivityState(object):
def __init__(self, channel):
self.lock = threading.RLock()
self.channel = channel
self.polling = False
self.connectivity = None
self.try_to_connect = False
self.callbacks_and_connectivities = []
self.delivering = False
def reset_postfork_child(self):
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:
cygrpc.block_if_fork_in_progress(state)
try:
callback(connectivity)
except Exception: # pylint: disable=broad-except
_LOGGER.exception(
_CHANNEL_SUBSCRIPTION_CALLBACK_ERROR_LOG_MESSAGE)
with state.lock:
callbacks = _deliveries(state)
if callbacks:
connectivity = state.connectivity
else:
state.delivering = False
return
def _spawn_delivery(state, callbacks):
delivering_thread = cygrpc.ForkManagedThread(target=_deliver,
args=(
state,
state.connectivity,
callbacks,
))
delivering_thread.setDaemon(True)
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)
while True:
event = channel.watch_connectivity_state(connectivity,
time.time() + 0.2)
cygrpc.block_if_fork_in_progress(state)
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 _subscribe(state, callback, try_to_connect):
with state.lock:
if not state.callbacks_and_connectivities and not state.polling:
polling_thread = cygrpc.ForkManagedThread(
target=_poll_connectivity,
args=(state, state.channel, bool(try_to_connect)))
polling_thread.setDaemon(True)
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 _augment_options(base_options, compression):
compression_option = _compression.create_channel_option(compression)
return tuple(base_options) + compression_option + ((
cygrpc.ChannelArgKey.primary_user_agent_string,
_USER_AGENT,
),)
def _separate_channel_options(options):
"""Separates core channel options from Python channel options."""
core_options = []
python_options = []
for pair in options:
if pair[0] == grpc.experimental.ChannelOptions.SingleThreadedUnaryStream:
python_options.append(pair)
else:
core_options.append(pair)
return python_options, core_options
class Channel(grpc.Channel):
"""A cygrpc.Channel-backed implementation of grpc.Channel."""
def __init__(self, target, options, credentials, compression):
"""Constructor.
Args:
target: The target to which to connect.
options: Configuration options for the channel.
credentials: A cygrpc.ChannelCredentials or None.
compression: An optional value indicating the compression method to be
used over the lifetime of the channel.
"""
python_options, core_options = _separate_channel_options(options)
self._single_threaded_unary_stream = _DEFAULT_SINGLE_THREADED_UNARY_STREAM
self._process_python_options(python_options)
self._channel = cygrpc.Channel(
_common.encode(target), _augment_options(core_options, compression),
credentials)
self._call_state = _ChannelCallState(self._channel)
self._connectivity_state = _ChannelConnectivityState(self._channel)
cygrpc.fork_register_channel(self)
def _process_python_options(self, python_options):
"""Sets channel attributes according to python-only channel options."""
for pair in python_options:
if pair[0] == grpc.experimental.ChannelOptions.SingleThreadedUnaryStream:
self._single_threaded_unary_stream = True
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, _channel_managed_call_management(self._call_state),
_common.encode(method), request_serializer, response_deserializer)
def unary_stream(self,
method,
request_serializer=None,
response_deserializer=None):
# NOTE(rbellevi): Benchmarks have shown that running a unary-stream RPC
# on a single Python thread results in an appreciable speed-up. However,
# due to slight differences in capability, the multi-threaded variant
# remains the default.
if self._single_threaded_unary_stream:
return _SingleThreadedUnaryStreamMultiCallable(
self._channel, _common.encode(method), request_serializer,
response_deserializer)
else:
return _UnaryStreamMultiCallable(
self._channel,
_channel_managed_call_management(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, _channel_managed_call_management(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, _channel_managed_call_management(self._call_state),
_common.encode(method), request_serializer, response_deserializer)
def _unsubscribe_all(self):
state = self._connectivity_state
if state:
with state.lock:
del state.callbacks_and_connectivities[:]
def _close(self):
self._unsubscribe_all()
self._channel.close(cygrpc.StatusCode.cancelled, 'Channel closed!')
cygrpc.fork_unregister_channel(self)
def _close_on_fork(self):
self._unsubscribe_all()
self._channel.close_on_fork(cygrpc.StatusCode.cancelled,
'Channel closed due to fork')
def __enter__(self):
return self
def __exit__(self, exc_type, exc_val, exc_tb):
self._close()
return False
def close(self):
self._close()
def __del__(self):
# TODO(https://github.com/grpc/grpc/issues/12531): Several releases
# after 1.12 (1.16 or thereabouts?) add a "self._channel.close" call
# here (or more likely, call self._close() here). We don't do this today
# because many valid use cases today allow the channel to be deleted
# immediately after stubs are created. After a sufficient period of time
# has passed for all users to be trusted to hang out to their channels
# for as long as they are in use and to close them after using them,
# then deletion of this grpc._channel.Channel instance can be made to
# effect closure of the underlying cygrpc.Channel instance.
try:
self._unsubscribe_all()
except: # pylint: disable=bare-except
# Exceptions in __del__ are ignored by Python anyway, but they can
# keep spamming logs. Just silence them.
pass