Question

我想编写一个只能在给定队列中执行的任务 - 如果有人试图将另一个队列传递到routing_key apply_async参数中，我想提出异常。我该怎么做？

Answer 1

您可以编写自己的任务，检查以确保在调用apply_async时传入有效的路由密钥。您也可以将其应用于队列。在配置中设置路由和队列：

import celery
from kombu import Queue, Exchange

app = celery.Celery('app')
app.conf.CELERY_QUEUES = (
    Queue('add', Exchange('default'), routing_key='good'),
)
app.conf.CELERY_ROUTES = {
    'app.add': {
        'queue': 'add',
        'routing_key': 'good'
    }
}

现在，创建自己的Task类，它将执行对路由键的检查。您需要覆盖apply_async：

class RouteCheckerTask(celery.Task):
    abstract = True

    def apply_async(self, args=None, kwargs=None, task_id=None, producer=None,
                                    link=None, link_error=None, **options):

        app = self._get_app()
        routing_key = options.get('routing_key', None)
        if routing_key:
            valid_routes = [v['routing_key'] for k, v in app.conf.CELERY_ROUTES.items()]
            is_valid = routing_key in valid_routes
            if not is_valid:
                raise NotImplementedError('{} is not a valid routing key. Options are: {}'.format(routing_key, valid_routes))
        if app.conf.CELERY_ALWAYS_EAGER:
            return self.apply(args, kwargs, task_id=task_id or uuid(), link=link, link_error=link_error, **options)
            # add 'self' if this is a "task_method".
        if self.__self__ is not None:
            args = args if isinstance(args, tuple) else tuple(args or ())
            args = (self.__self__, ) + args
        return app.send_task(
            self.name, args, kwargs, task_id=task_id, producer=producer,
            link=link, link_error=link_error, result_cls=self.AsyncResult,
            **dict(self._get_exec_options(), **options)
        )

从这个任务开始，并正常调用apply_async：

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

# Fails
add.apply_async([1, 2], routing_key='bad')
# Passes
add.apply_async([1, 2], routing_key='good')

如何将Celery任务绑定到特定队列？

1 个答案: