169 lines
5.1 KiB
Python
169 lines
5.1 KiB
Python
# Copyright 2015 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.
|
|
"""Internal utilities for gRPC Python."""
|
|
|
|
import collections
|
|
import threading
|
|
import time
|
|
import logging
|
|
|
|
import six
|
|
|
|
import grpc
|
|
from grpc import _common
|
|
|
|
_LOGGER = logging.getLogger(__name__)
|
|
|
|
_DONE_CALLBACK_EXCEPTION_LOG_MESSAGE = (
|
|
'Exception calling connectivity future "done" callback!')
|
|
|
|
|
|
class RpcMethodHandler(
|
|
collections.namedtuple('_RpcMethodHandler', (
|
|
'request_streaming',
|
|
'response_streaming',
|
|
'request_deserializer',
|
|
'response_serializer',
|
|
'unary_unary',
|
|
'unary_stream',
|
|
'stream_unary',
|
|
'stream_stream',
|
|
)), grpc.RpcMethodHandler):
|
|
pass
|
|
|
|
|
|
class DictionaryGenericHandler(grpc.ServiceRpcHandler):
|
|
|
|
def __init__(self, service, method_handlers):
|
|
self._name = service
|
|
self._method_handlers = {
|
|
_common.fully_qualified_method(service, method): method_handler
|
|
for method, method_handler in six.iteritems(method_handlers)
|
|
}
|
|
|
|
def service_name(self):
|
|
return self._name
|
|
|
|
def service(self, handler_call_details):
|
|
return self._method_handlers.get(handler_call_details.method)
|
|
|
|
|
|
class _ChannelReadyFuture(grpc.Future):
|
|
|
|
def __init__(self, channel):
|
|
self._condition = threading.Condition()
|
|
self._channel = channel
|
|
|
|
self._matured = False
|
|
self._cancelled = False
|
|
self._done_callbacks = []
|
|
|
|
def _block(self, timeout):
|
|
until = None if timeout is None else time.time() + timeout
|
|
with self._condition:
|
|
while True:
|
|
if self._cancelled:
|
|
raise grpc.FutureCancelledError()
|
|
elif self._matured:
|
|
return
|
|
else:
|
|
if until is None:
|
|
self._condition.wait()
|
|
else:
|
|
remaining = until - time.time()
|
|
if remaining < 0:
|
|
raise grpc.FutureTimeoutError()
|
|
else:
|
|
self._condition.wait(timeout=remaining)
|
|
|
|
def _update(self, connectivity):
|
|
with self._condition:
|
|
if (not self._cancelled and
|
|
connectivity is grpc.ChannelConnectivity.READY):
|
|
self._matured = True
|
|
self._channel.unsubscribe(self._update)
|
|
self._condition.notify_all()
|
|
done_callbacks = tuple(self._done_callbacks)
|
|
self._done_callbacks = None
|
|
else:
|
|
return
|
|
|
|
for done_callback in done_callbacks:
|
|
try:
|
|
done_callback(self)
|
|
except Exception: # pylint: disable=broad-except
|
|
_LOGGER.exception(_DONE_CALLBACK_EXCEPTION_LOG_MESSAGE)
|
|
|
|
def cancel(self):
|
|
with self._condition:
|
|
if not self._matured:
|
|
self._cancelled = True
|
|
self._channel.unsubscribe(self._update)
|
|
self._condition.notify_all()
|
|
done_callbacks = tuple(self._done_callbacks)
|
|
self._done_callbacks = None
|
|
else:
|
|
return False
|
|
|
|
for done_callback in done_callbacks:
|
|
try:
|
|
done_callback(self)
|
|
except Exception: # pylint: disable=broad-except
|
|
_LOGGER.exception(_DONE_CALLBACK_EXCEPTION_LOG_MESSAGE)
|
|
|
|
return True
|
|
|
|
def cancelled(self):
|
|
with self._condition:
|
|
return self._cancelled
|
|
|
|
def running(self):
|
|
with self._condition:
|
|
return not self._cancelled and not self._matured
|
|
|
|
def done(self):
|
|
with self._condition:
|
|
return self._cancelled or self._matured
|
|
|
|
def result(self, timeout=None):
|
|
self._block(timeout)
|
|
|
|
def exception(self, timeout=None):
|
|
self._block(timeout)
|
|
|
|
def traceback(self, timeout=None):
|
|
self._block(timeout)
|
|
|
|
def add_done_callback(self, fn):
|
|
with self._condition:
|
|
if not self._cancelled and not self._matured:
|
|
self._done_callbacks.append(fn)
|
|
return
|
|
|
|
fn(self)
|
|
|
|
def start(self):
|
|
with self._condition:
|
|
self._channel.subscribe(self._update, try_to_connect=True)
|
|
|
|
def __del__(self):
|
|
with self._condition:
|
|
if not self._cancelled and not self._matured:
|
|
self._channel.unsubscribe(self._update)
|
|
|
|
|
|
def channel_ready_future(channel):
|
|
ready_future = _ChannelReadyFuture(channel)
|
|
ready_future.start()
|
|
return ready_future
|