在升级celery 4.x以后使用rabbitmq为broker运行任务抛出如下异常:
[2018-06-29 09:32:14,622: CRITICAL/MainProcess] Unrecoverable error: PreconditionFailed(406, "PRECONDITION_FAILED - inequivalent arg 'x-expires' for queue 'celery@PQ
SZ-L01395.celery.pidbox' in vhost '/': received the value '10000' of type 'signedint' but current is none", (50, 10), 'Queue.declare')
Traceback (most recent call last):
File "c:\programdata\anaconda3\lib\site-packages\celery\worker\worker.py", line 205, in start
self.blueprint.start(self)
.......
File "c:\programdata\anaconda3\lib\site-packages\amqp\channel.py", line 277, in _on_close
reply_code, reply_text, (class_id, method_id), ChannelError,
amqp.exceptions.PreconditionFailed: Queue.declare: (406) PRECONDITION_FAILED - inequivalent arg 'x-expires' for queue '[email protected]' in vhost '/'
: received the value '10000' of type 'signedint' but current is none出现该错误的原因一般是因为rabbitmq的客户端和服务端参数不一致导致的，将其参数保持一致即可。
比如这里提示是x-expires 对应的celery中的配置是control_queue_expires。因此只需要在配置文件中加上control_queue_expires = None即可。
在celery 3.x中是没有这两项配置的，在4.x中必须保证这两项配置的一致性，不然就会抛出如上的异常。
我这里遇到的了两个rabbitmq的配置与celery配置的映射关系如下表：
| rabbitmq | celery4.x |
|---|---|
| x-expires | control_queue_expires |
| x-message-ttl | control_queue_ttl |