芹菜“入门”无法检索结果；始终挂起

Question

我一直在试着跟着芹菜指南First Steps With Celery和Next Steps。我的设置是Windows 7 64位，Anaconda Python 2.7（32位），安装了Erlang 32位二进制文件，RabbitMQ服务器和芹菜（使用pip install celery）。

根据指南，我创建了一个proj文件夹，其中包含init.py、tasks.py和celeriy.py。Myinit.py为空。这是芹菜.py：

from __future__ import absolute_import

from celery import Celery

app = Celery('proj',
             broker='amqp://',
             backend='amqp://',
             include=['proj.tasks'])

#Optional configuration, see the application user guide
app.conf.update(
    CELERY_TASK_RESULT_EXPIRES=3600,
    CELERY_TASK_SERIALIZER='json',
    CELERY_ACCEPT_CONTENT=['json'],  # Ignore other content
    CELERY_RESULT_SERIALIZER='json',
)

if __name__ == '__main__':
    app.start()

这里是tasks.py：

from __future__ import absolute_import

from .celery import app

@app.task
def add(x, y):
    return x + y


@app.task
def mul(x, y):
    return x * y


@app.task
def xsum(numbers):
    return sum(numbers)

首先我知道我应该确保RabbitMQ服务正在运行。任务管理器的Services选项卡显示RabbitMQ确实在运行。要启动芹菜服务器并加载我的任务，请打开cmd.exe，导航到proj（我称之为芹菜演示的文件夹）的父文件夹，然后运行以下命令：

celery -A proj.celery worker -l debug

从而产生以下输出：

C:\Users\bnables\Documents\Python\celery_demo>celery -A proj.celery worker -l debug
[2014-08-25 17:00:09,308: DEBUG/MainProcess] | Worker: Preparing bootsteps.
[2014-08-25 17:00:09,313: DEBUG/MainProcess] | Worker: Building graph...
[2014-08-25 17:00:09,315: DEBUG/MainProcess] | Worker: New boot order: {Timer, Hub, Queues (intra), Pool, Autoreloader, Autoscaler, StateDB, Beat, Con
sumer}
[2014-08-25 17:00:09,322: DEBUG/MainProcess] | Consumer: Preparing bootsteps.
[2014-08-25 17:00:09,322: DEBUG/MainProcess] | Consumer: Building graph...
[2014-08-25 17:00:09,332: DEBUG/MainProcess] | Consumer: New boot order: {Connection, Events, Heart, Mingle, Gossip, Tasks, Control, Agent, event loop
}

 -------------- celery@MSSLW40013047 v3.1.13 (Cipater)
---- **** -----
--- * ***  * -- Windows-7-6.1.7601-SP1
-- * - **** ---
- ** ---------- [config]
- ** ---------- .> app:         proj:0x3290370
- ** ---------- .> transport:   amqp://guest:**@localhost:5672//
- ** ---------- .> results:     amqp
- *** --- * --- .> concurrency: 8 (prefork)
-- ******* ----
--- ***** ----- [queues]
 -------------- .> celery           exchange=celery(direct) key=celery


[tasks]
  . celery.backend_cleanup
  . celery.chain
  . celery.chord
  . celery.chord_unlock
  . celery.chunks
  . celery.group
  . celery.map
  . celery.starmap
  . proj.tasks.add
  . proj.tasks.mul
  . proj.tasks.xsum

[2014-08-25 17:00:09,345: DEBUG/MainProcess] | Worker: Starting Pool
[2014-08-25 17:00:09,417: DEBUG/MainProcess] ^-- substep ok
[2014-08-25 17:00:09,420: DEBUG/MainProcess] | Worker: Starting Consumer
[2014-08-25 17:00:09,421: DEBUG/MainProcess] | Consumer: Starting Connection
[2014-08-25 17:00:09,457: DEBUG/MainProcess] Start from server, version: 0.9, properties: {u'information': u'Licensed under the MPL.  See http://www.r
abbitmq.com/', u'product': u'RabbitMQ', u'copyright': u'Copyright (C) 2007-2014 GoPivotal, Inc.', u'capabilities': {u'exchange_exchange_bindings': Tru
e, u'connection.blocked': True, u'authentication_failure_close': True, u'basic.nack': True, u'per_consumer_qos': True, u'consumer_priorities': True, u
'consumer_cancel_notify': True, u'publisher_confirms': True}, u'cluster_name': u'rabbit@MSSLW40013047.ndc.nasa.gov', u'platform': u'Erlang/OTP', u'ver
sion': u'3.3.5'}, mechanisms: [u'AMQPLAIN', u'PLAIN'], locales: [u'en_US']
[2014-08-25 17:00:09,460: DEBUG/MainProcess] Open OK!
[2014-08-25 17:00:09,460: INFO/MainProcess] Connected to amqp://guest:**@127.0.0.1:5672//
[2014-08-25 17:00:09,461: DEBUG/MainProcess] ^-- substep ok
[2014-08-25 17:00:09,461: DEBUG/MainProcess] | Consumer: Starting Events
[2014-08-25 17:00:09,516: DEBUG/MainProcess] Start from server, version: 0.9, properties: {u'information': u'Licensed under the MPL.  See http://www.r
abbitmq.com/', u'product': u'RabbitMQ', u'copyright': u'Copyright (C) 2007-2014 GoPivotal, Inc.', u'capabilities': {u'exchange_exchange_bindings': Tru
e, u'connection.blocked': True, u'authentication_failure_close': True, u'basic.nack': True, u'per_consumer_qos': True, u'consumer_priorities': True, u
'consumer_cancel_notify': True, u'publisher_confirms': True}, u'cluster_name': u'rabbit@MSSLW40013047.ndc.nasa.gov', u'platform': u'Erlang/OTP', u'ver
sion': u'3.3.5'}, mechanisms: [u'AMQPLAIN', u'PLAIN'], locales: [u'en_US']
[2014-08-25 17:00:09,519: DEBUG/MainProcess] Open OK!
[2014-08-25 17:00:09,520: DEBUG/MainProcess] using channel_id: 1
[2014-08-25 17:00:09,522: DEBUG/MainProcess] Channel open
[2014-08-25 17:00:09,523: DEBUG/MainProcess] ^-- substep ok
[2014-08-25 17:00:09,523: DEBUG/MainProcess] | Consumer: Starting Heart
[2014-08-25 17:00:09,530: DEBUG/MainProcess] ^-- substep ok
[2014-08-25 17:00:09,533: DEBUG/MainProcess] | Consumer: Starting Mingle
[2014-08-25 17:00:09,538: INFO/MainProcess] mingle: searching for neighbors
[2014-08-25 17:00:09,539: DEBUG/MainProcess] using channel_id: 1
[2014-08-25 17:00:09,540: DEBUG/MainProcess] Channel open
[2014-08-25 17:00:10,552: INFO/MainProcess] mingle: all alone
[2014-08-25 17:00:10,552: DEBUG/MainProcess] ^-- substep ok
[2014-08-25 17:00:10,552: DEBUG/MainProcess] | Consumer: Starting Gossip
[2014-08-25 17:00:10,553: DEBUG/MainProcess] using channel_id: 2
[2014-08-25 17:00:10,555: DEBUG/MainProcess] Channel open
[2014-08-25 17:00:10,559: DEBUG/MainProcess] ^-- substep ok
[2014-08-25 17:00:10,559: DEBUG/MainProcess] | Consumer: Starting Tasks
[2014-08-25 17:00:10,566: DEBUG/MainProcess] ^-- substep ok
[2014-08-25 17:00:10,566: DEBUG/MainProcess] | Consumer: Starting Control
[2014-08-25 17:00:10,568: DEBUG/MainProcess] using channel_id: 3
[2014-08-25 17:00:10,569: DEBUG/MainProcess] Channel open
[2014-08-25 17:00:10,572: DEBUG/MainProcess] ^-- substep ok
[2014-08-25 17:00:10,573: DEBUG/MainProcess] | Consumer: Starting event loop
[2014-08-25 17:00:10,575: WARNING/MainProcess] celery@MSSLW40013047 ready.
[2014-08-25 17:00:10,575: DEBUG/MainProcess] basic.qos: prefetch_count->32

-A告诉芹菜哪里可以找到我的芹菜应用程序实例。只使用proj也可以，但是由于它将只搜索proj.celery，所以在这里更显式是很好的。worker是给芹菜的命令，它告诉芹菜生成一些工人来执行它从proj.celeri加载的任务。最后-l debug告诉芹菜设置要调试的日志级别，以便我获得大量信息。这通常是-l info。

为了测试我的任务服务器，我打开了一个IPython Qt控制台并导航到celery_demo文件夹（其中包含proj）。然后我输入from proj.tasks import add。简单地调用add(1, 2)返回3，而不使用服务器，如预期的那样。当我调用add.delay时，将发生以下情况：

add.delay(2, 3)

返回：

<AsyncResult: 42123ff3-e94e-4673-808a-ec6c847679d8>

在我的cmd.exe窗口中，我得到：

[2014-08-25 17:20:38,109: INFO/MainProcess] Received task: proj.tasks.add[42123ff3-e94e-4673-808a-ec6c847679d8]
[2014-08-25 17:20:38,109: DEBUG/MainProcess] TaskPool: Apply <function _fast_trace_task at 0x033CD6F0> (args:(u'proj.tasks.add', u'42123ff3-e94e-4673-
808a-ec6c847679d8', [2, 3], {}, {u'timelimit': [None, None], u'utc': True, u'is_eager': False, u'chord': None, u'group': None, u'args': [2, 3], u'retr
ies': 0, u'delivery_info': {u'priority': None, u'redelivered': False, u'routing_key': u'celery', u'exchange': u'celery'}, u'expires': None, u'hostname
': 'celery@MSSLW40013047', u'task': u'proj.tasks.add', u'callbacks': None, u'correlation_id': u'42123ff3-e94e-4673-808a-ec6c847679d8', u'errbacks': No
ne, u'reply_to': u'70ed001d-193c-319c-9447-8d77c231dc10', u'taskset': None, u'kwargs': {}, u'eta': None, u'id': u'42123ff3-e94e-4673-808a-ec6c847679d8
', u'headers': {}}) kwargs:{})
[2014-08-25 17:20:38,124: DEBUG/MainProcess] Task accepted: proj.tasks.add[42123ff3-e94e-4673-808a-ec6c847679d8] pid:4052
[2014-08-25 17:20:38,125: INFO/MainProcess] Task proj.tasks.add[42123ff3-e94e-4673-808a-ec6c847679d8] succeeded in 0.0130000114441s: 5

如最后一行所示，正在计算5的结果。接下来，我要存储AsyncResult对象并检查其状态并获取结果值：

result = add.delay(3, 4)

但是result.state和result.get（timeout=1）不能按预期工作：

In:  result.state
Out: 'Pending'
In:  result.status
Out: 'Pending'

In: result.get(timeout=1)
---------------------------------------------------------------------------
TimeoutError                              Traceback (most recent call last)
<ipython-input-17-375f2d3530cb> in <module>()
----> 1 result.get(timeout=1)

C:\Anaconda32\lib\site-packages\celery\result.pyc in get(self, timeout, propagate, interval, no_ack, follow_parents)
    167                 interval=interval,
    168                 on_interval=on_interval,
--> 169                 no_ack=no_ack,
    170             )
    171         finally:

C:\Anaconda32\lib\site-packages\celery\backends\amqp.pyc in wait_for(self, task_id, timeout, cache, propagate, no_ack, on_interval, READY_STATES, PROPAGATE_STATES, **kwargs)
    155                                     on_interval=on_interval)
    156             except socket.timeout:
--> 157                 raise TimeoutError('The operation timed out.')
    158 
    159         if meta['status'] in PROPAGATE_STATES and propagate:

TimeoutError: The operation timed out.

其中result.state或result.status的预期结果是“成功的”，而result.get(timeout=1)的结果应该是5。

结果存储或消息传递似乎工作不正常。本教程只是说在调用Celery()或CELERY_RESULT_BACKEND配置设置中设置backend命名参数。在“入门”中，它有backend='amqp'，其中“下一步”有backend='amqp://'，这也用于github examples。

我已经在这上面敲了一阵子脑袋，几乎不知道该怎么做。对下一步该怎么做有什么想法吗？谢谢！