How to update a worker without stopping the queue?

Question

Message Queues

Let's say RabbitMQ is already running on the server, the workers are working. But they made an update in the worker script (changed some code).
How to download these updates so that we do not restart all the workers, but in order for them to work, we downloaded the update, the workers completed their work completely, and then the workers with the new update were already launched?
In general, how to make a seamless update of the workers / queue server?

Answer 1

Nginx in this case starts new children that process new requests and kills the old ones as soon as they finish.