标签：log 文件 sql play packages context detail str 时报
本系列文章的开发环境：
window 7 + python2.7 + pycharm5 + celery3.1.25 + django1.9.4
在我们日常的开发工作中，经常会遇到这几种情况：
1、在web应用中，用户触发一个操作，执行后台处理程序，这个程序需要执行很长时间才能返回结果。怎样才能不阻塞http请求，不让用户等待从而提高用户体验呢？
2、定时任务脚本：生产环境经常会跑一些定时任务脚本，假如你有上千台的服务器、上千种任务，定时任务的管理很困难，如何对job进行有效的管理？
3、异步需求：比如发送短信/邮件、推送消息、清理/设置缓存？
如果你有以上的需求，那么Celery可能对你很有用。
Celery是一个可以处理大量消息的分布式任务系统，它凭借简单、灵活、可靠的特性被广泛使用。Celery聚焦于实时处理任务，同时也支持定时的任务调度。
从上图中可以知道Celery包含如下组件：
这里Broker和Result Backend都选择RabbitMQ。
2) 安装Celery 3.1.25
为什么选择这个低版本？请见最下面的问题列表。
pip install celery==3.1.25
2.1） 在一个目录中创建tasks.py文件，内容如下：
from celery import Celery
#创建celery实例，其中backend表示采用rpc瞬态信息，不保存到数据库；broker表示连接RabbitMQ URL app = Celery(‘tasks‘,backend=‘rpc://‘,broker=‘pyamqp://guest@localhost//‘) @app.task def hello(): return "hello celery"
2.2） 启动celery worker
到tasks.py文件那层目录，执行以下命令：
celery -A tasks worker --loglevel=info
启动输出信息如下：
E:\workdir\test_pro>celery -A tasks worker --loglevel=info [2017-05-10 18:26:18,298: WARNING/MainProcess] c:\python27\lib\site-packages\celery\apps\worker.py:161: CDeprecationWarnin Starting from version 3.2 Celery will refuse to accept pickle by default. The pickle serializer is a security concern as it may give attackers the ability to execute any command. It‘s important to secure your broker from unauthorized access when using pickle, so we think that enabling pickle should require a deliberate action and not be the default choice. If you depend on pickle then you should set a setting to disable this warning and to be sure that everything will continue working when you upgrade to Celery 3.2:: CELERY_ACCEPT_CONTENT = [‘pickle‘, ‘json‘, ‘msgpack‘, ‘yaml‘] You must only enable the serializers that you will actually use. warnings.warn(CDeprecationWarning(W_PICKLE_DEPRECATED)) -------------- celery@507B9D97E083 v3.1.25 (Cipater) ---- **** ----- --- * *** * -- Windows-7-6.1.7601-SP1 -- * - **** --- - ** ---------- [config] - ** ---------- .> app: tasks:0x35fc240 - ** ---------- .> transport: amqp://guest:**@localhost:5672// - ** ---------- .> results: rpc:// - *** --- * --- .> concurrency: 4 (prefork) -- ******* ---- --- ***** ----- [queues] -------------- .> celery exchange=celery(direct) key=celery [tasks] . tasks.hello [2017-05-10 18:26:18,433: INFO/MainProcess] Connected to amqp://guest:**@127.0.0.1:5672// [2017-05-10 18:26:18,483: INFO/MainProcess] mingle: searching for neighbors [2017-05-10 18:26:19,497: INFO/MainProcess] mingle: all alone [2017-05-10 18:26:19,523: WARNING/MainProcess] celery@507B9D97E083 ready.
2.3） 测试结果
另起一个终端，还是到tasks.py那层目录，进入python命令行：
这时celery worker会有提示信息：
到此为止，celery入门就介绍到这里了，下一节介绍如何在django中使用celery。
1、启动celery worker时报错
ERROR:
`[2016-11-05 20:23:25,759: CRITICAL/MainProcess] Unrecoverable error: TypeError(‘must be integer, not _subprocess_handle‘,)
Traceback (most recent call last):
File "c:\development\env\zillow2\lib\site-packages\celery\worker\worker.py", line 203, in start
self.blueprint.start(self)
File "c:\development\env\zillow2\lib\site-packages\celery\bootsteps.py", line 119, in start
step.start(parent)
File "c:\development\env\zillow2\lib\site-packages\celery\bootsteps.py", line 370, in start
return self.obj.start()
File "c:\development\env\zillow2\lib\site-packages\celery\concurrency\base.py", line 131, in start
self.on_start()
File "c:\development\env\zillow2\lib\site-packages\celery\concurrency\prefork.py", line 112, in on_start
**self.options)
File "c:\development\env\zillow2\lib\site-packages\billiard\pool.py", line 1008, in init
self._create_worker_process(i)
File "c:\development\env\zillow2\lib\site-packages\billiard\pool.py", line 1117, in _create_worker_process
w.start()
File "c:\development\env\zillow2\lib\site-packages\billiard\process.py", line 122, in start
self._popen = self._Popen(self)
File "c:\development\env\zillow2\lib\site-packages\billiard\context.py", line 383, in _Popen
return Popen(process_obj)
File "c:\development\env\zillow2\lib\site-packages\billiard\popen_spawn_win32.py", line 64, in init
_winapi.CloseHandle(ht)
TypeError: must be integer, not _subprocess_handle
(zillow2) C:\DEVELOPMENT\zillow2\project>Traceback (most recent call last):
File "", line 1, in
File "c:\development\env\zillow2\lib\site-packages\billiard\spawn.py", line 159, in spawn_main
new_handle = steal_handle(parent_pid, pipe_handle)
File "c:\development\env\zillow2\lib\site-packages\billiard\reduction.py", line 121, in steal_handle
_winapi.PROCESS_DUP_HANDLE, False, source_pid)
WindowsError: [Error 87] The parameter is incorrect
解决方案：这是因为windows系统不支持celery4以上版本，请降级到3.xx即可解决该问题
参考文档：https://zhuanlan.zhihu.com/p/22304455
标签：log 文件 sql play packages context detail str 时报
原文地址：http://www.cnblogs.com/mysql-dba/p/6837494.html
