Symfony Messenger 消费者池

Question

I'm not sure this is something possible: to have a pool of messenger consumers for the same queue ?

I've tried to use the Redis consumer= options but that's not it.

Maybe a "pool" middleware could do some routing to specific transports?

Answer 1

Yes, you use multiple consumers for one queue. Symfony Messenger is designed to have multiple consumers. The example configuration from the Supervisor part of the documentation already has 2 instances:

Supervisor configuration files typically live in a /etc/supervisor/conf.d directory. For example, you can create a new messenger-worker.conf file there to make sure that 2 instances of messenger:consume are running at all times:

(..)

So you can just run bin/console messenger:consume async multiple times and in most cases, this will work without additional configuration. There is a warning about using the Redis Transport and multiple workers:

If you use the Redis Transport, note that each worker needs a unique consumer name to avoid the same message being handled by multiple workers. One way to achieve this is to set an environment variable in the Supervisor configuration file, which you can then refer to in messenger.yaml (see Redis section above):

environment=MESSENGER_CONSUMER_NAME=%(program_name)s_%(process_num)02d