Celery 错误：“str 对象不可调用”，getstate() 函数是一个字符串

Question

当我尝试将任务传递给 Celery 工作人员时，我收到此错误。这是回溯

Traceback:
File "/home/vivek/xpython/lib/python2.6/site-packages/Django-1.3-py2.6.egg/django/core/handlers/base.py" in get_response
111.                         response = callback(request, *callback_args, **callback_kwargs)

File "/home/vivek/projects/engine/engine/web/models.py" in fb_sync
53.         process_metadata.delay(self, wrapper)

File "/home/vivek/xpython/lib/python2.6/site-packages/celery-2.2.7-py2.6.egg/celery/task/base.py" in delay
338.         return self.apply_async(args, kwargs)

File "/home/vivek/xpython/lib/python2.6/site-packages/celery-2.2.7-py2.6.egg/celery/task/base.py" in apply_async
460.                                          **options)

File "/home/vivek/xpython/lib/python2.6/site-packages/celery-2.2.7-py2.6.egg/celery/app/amqp.py" in delay_task
230.         send(body, exchange=exchange, **extract_msg_options(kwargs))

File "/home/vivek/xpython/lib/python2.6/site-packages/kombu-1.1.6-py2.6.egg/kombu/compat.py" in send
101.         return self.publish(*args, **kwargs)

File "/home/vivek/xpython/lib/python2.6/site-packages/kombu-1.1.6-py2.6.egg/kombu/messaging.py" in publish
124.                 compression, headers)

File "/home/vivek/xpython/lib/python2.6/site-packages/kombu-1.1.6-py2.6.egg/kombu/messaging.py" in _prepare
147.              body) = encode(body, serializer=serializer)

File "/home/vivek/xpython/lib/python2.6/site-packages/kombu-1.1.6-py2.6.egg/kombu/serialization.py" in encode
119.         payload = encoder(data)

File "/home/vivek/xpython/lib/python2.6/copy_reg.py" in _reduce_ex
84.         dict = getstate()



 Exception Type: TypeError at /login/
  Exception Value: 'str' object is not callable

    /home/vivek/xpython/lib/python2.6/copy_reg.py in _reduce_ex
        dict = getstate() ...

local variables
 {'args': (<web.models.User object at 0x8b47b4c>,<web.fb.Facebook object at 0x8b4fbac>),
 'eta': None,
 'expires': None,
 'id': '8d8e6c0b-a269-4780-9c48-77e689037322',
 'kwargs': {},
 'retries': 0,
 'task': 'web.models.process_likes'}


What is the solution to this problem? When I remove the task decorator, it works fine.

Answer 1

您正尝试将对象传递给无法序列化的任务。尝试传递更简单的数据（让您在任务运行时重新创建复杂对象的信息）。

不确定这是否是错误的实际原因，但无论如何您都不应该将 Django 模型传递给任务。否则你会遇到竞争条件。请参阅有关该主题的 Celery 文档：

它们不应该作为参数传递给任务。当任务运行时从数据库重新获取对象几乎总是更好，因为使用旧数据可能会导致竞争条件。

将用户对象的唯一键以及识别 Facebook Like 交互所需的任何内容传递为简单的 Python 类型，并使用任务中的该信息来重新创建执行该任务所需的内容。