无法将Celery服务器连接到本地主机上的RabbitMQ
我使用Celery和RabbitMQ作为消息队列，每个封装在它自己的Docker镜像中。 当它们在Docker中使用--link参数连接时，一切正常。 我已经有这个设置工作一段时间了。 我想将它们分开，以便它们在不同的主机上运行，所以我不能再使用--link参数。 我越来越gaierror: [Errno -2] Name or service not known当我尝试连接使用AMQP，不明白为什么。
服务器只是使用rabbitmq上的rabbitmq容器：
docker run --rm --name=qrabbit -p 5672:5672 rabbitmq
我可以成功地telnet到这个：
$ telnet 192.168.99.100 5672 Trying 192.168.99.100... Connected to 192.168.99.100. Escape character is '^]'. abc ^D AMQP Connection closed by foreign host. $
…所以我知道服务器正在运行。
我的客户看起来像这样：
import os from logging import getLogger, StreamHandler, DEBUG from serverlib import QueueServer, CeleryMonitor from celery import Celery from argparse import ArgumentParser log = getLogger('server') log.addHandler(StreamHandler()) log.setLevel(DEBUG) broker_service_host = os.environ.get('MESSAGE_QUEUE_SERVICE_SERVICE_HOST') broker = 'amqp://{0}'.format(broker_service_host) host = '' port = 8000 retry = 5 if __name__ == '__main__': log.info('connecting to {0}, {1}:{2}, retry={3}'.format(broker, host, port, retry)) app = Celery(broker=broker) monitor = CeleryMonitor(app, retry=retry) server = QueueServer((host, port), app) monitor.start() try: log.info('listening on {0}:{1}'.format(host, port)) server.serve_forever() except KeyboardInterrupt: log.info('shutdown requested') except BaseException as e: log.error(e) finally: monitor.shutdown()
我有点确定外部模块（QueueServer和CeleryMonitor）不是问题的一部分，因为它在我执行以下操作时正常运行：
$ docker run --rm --name=qmaster -e "MESSAGE_QUEUE_SERVICE_SERVICE_HOST=localhost" --link qrabbit:rabbit -p 80:8000 render-task-master connecting to amqp://localhost, :8000, retry=5 listening on :8000 ^Cshutdown requested $
…但不是如果我做以下（没有 – --link参数）：
$ docker run --rm --name=qmaster -e "MESSAGE_QUEUE_SERVICE_SERVICE_HOST=localhost" -p 80:8000 render-task-master connecting to amqp://localhost, :8000, retry=5 listening on :8000 Exception in thread Thread-1: Traceback (most recent call last): File "/usr/local/lib/python2.7/threading.py", line 810, in __bootstrap_inner self.run() File "/home/celery/serverlib/celerymonitor.py", line 68, in run '*': self.__state.event File "/usr/local/lib/python2.7/site-packages/celery/events/__init__.py", line 287, in __init__ self.channel = maybe_channel(channel) File "/usr/local/lib/python2.7/site-packages/kombu/connection.py", line 1054, in maybe_channel return channel.default_channel File "/usr/local/lib/python2.7/site-packages/kombu/connection.py", line 756, in default_channel self.connection File "/usr/local/lib/python2.7/site-packages/kombu/connection.py", line 741, in connection self._connection = self._establish_connection() File "/usr/local/lib/python2.7/site-packages/kombu/connection.py", line 696, in _establish_connection conn = self.transport.establish_connection() File "/usr/local/lib/python2.7/site-packages/kombu/transport/pyamqp.py", line 116, in establish_connection conn = self.Connection(**opts) File "/usr/local/lib/python2.7/site-packages/amqp/connection.py", line 165, in __init__ self.transport = self.Transport(host, connect_timeout, ssl) File "/usr/local/lib/python2.7/site-packages/amqp/connection.py", line 186, in Transport return create_transport(host, connect_timeout, ssl) File "/usr/local/lib/python2.7/site-packages/amqp/transport.py", line 299, in create_transport return TCPTransport(host, connect_timeout) File "/usr/local/lib/python2.7/site-packages/amqp/transport.py", line 75, in __init__ socket.SOCK_STREAM, SOL_TCP): gaierror: [Errno -2] Name or service not known ^Cshutdown requested $
使用和不使用可能导致此错误的--link参数有什么区别？
更新：
我已经缩小到我创build的监视器类中的一个错误：
recv = self.app.events.Receiver(connection, handlers={ 'task-received': self.registerTask, 'task-failed': self.retryTask, 'task-succeeded': self.deregisterTask, # should process all events to have state up to date '*': self.__state.event })
当这个被调用，它坐几秒钟（超时？），然后抛出一个exception。 任何想法为什么这不会像amqp://localhost指定的amqp URL，但是当我使用–link参数时，一切正常？
以下是调用的全部方法，以获取其他上下文：
def run(self): log.info('run') self.__state = self.app.events.State() with self.app.connection() as connection: log.info('got a connection') recv = self.app.events.Receiver(connection, handlers={ 'task-received': self.registerTask, 'task-failed': self.retryTask, 'task-succeeded': self.deregisterTask, # should process all events to have state up to date '*': self.__state.event }) log.info('received receiver') # Capture until shutdown requested while not self.__shutdown: log.info('main run loop') try: recv.capture(limit=None, timeout=1, wakeup=True) except timeout: # timeout exception is fired when nothing occurs # during timeout. Just ignore it. pass
我发现这个问题：我已经在运行容器的Docker环境中设置了CELERY_BROKER_URL ，这导致后端尝试连接到一个不存在的主机名。 一旦我取消设置variables，所有的东西都可以正确地连接到我的环境中。
$ docker inspect server <... removed ...> "Env": [ "MESSAGE_QUEUE_SERVICE_SERVICE_HOST=192.168.99.100", "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin", "LANG=C.UTF-8", "PYTHON_VERSION=2.7.10", "PYTHON_PIP_VERSION=7.1.2", "CELERY_VERSION=3.1.18", "CELERY_BROKER_URL=amqp://guest@rabbit" ], <... removed ...>