oslo.messaging/oslo_messaging/_executors/impl_aioeventlet.py
Doug Hellmann 1b390c34b0 add plugin documentation for executors and notifiers
Document the plugins available for executors and notifiers.

Fix the formatting in the aioeventlet executor so the docstring renders
properly.

Change-Id: I7709b65f5aa68fab3822b4de11640309aa07b1d7
2015-07-20 18:30:00 +00:00

75 lines
2.5 KiB
Python

# Copyright 2014 eNovance.
#
# 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.
import aioeventlet
import trollius
from oslo_messaging._executors import impl_eventlet
class AsyncioEventletExecutor(impl_eventlet.EventletExecutor):
"""A message executor which integrates with eventlet and trollius.
The executor is based on eventlet executor and so is compatible with it.
The executor supports trollius coroutines, explicit asynchronous
programming, in addition to eventlet greenthreads, implicit asynchronous
programming.
To use the executor, an aioeventlet event loop must the running in the
thread executing the executor (usually the main thread). Example of code to
setup and run an aioeventlet event loop for the executor (in the main
thread)::
import aioeventlet
import trollius
policy = aioeventlet.EventLoopPolicy()
trollius.set_event_loop_policy(policy)
def run_loop(loop):
loop.run_forever()
loop.close()
# Get the aioeventlet event loop (create it if needed)
loop = trollius.get_event_loop()
# run the event loop in a new greenthread,
# close it when it is done
eventlet.spawn(run_loop, loop)
"""
def __init__(self, conf, listener, dispatcher):
super(AsyncioEventletExecutor, self).__init__(conf, listener,
dispatcher)
self._loop = None
def start(self):
# check that the event loop is an aioeventlet event loop
loop = trollius.get_event_loop()
if not isinstance(loop, aioeventlet.EventLoop):
raise RuntimeError("need an aioeventlet event loop")
self._loop = loop
super(AsyncioEventletExecutor, self).start()
def _coroutine_wrapper(self, func, *args, **kw):
result = func(*args, **kw)
if trollius.iscoroutine(result):
result = aioeventlet.yield_future(result, loop=self._loop)
return result
_executor_callback = _coroutine_wrapper