In my system I use spring-cloud-stream and RabbitMQ for sending and receiving events. I got my RabbitMQ running, service A up and service B down. Service A sends an event to service B. Then I turn up my service B and now I expect Rabbit to deliever the event - but nothing happens. Is it correct behaviour? I'm new to RabbitMQ but I though that it should guarantee that all events will eventually finds its receivers. My application is simple, based on example on github with no extra configuration. What do I miss?
If your consumers don't have a group, the queue is an anonymous, auto-delete queue. You need a group for persistence. See consumer groups.
Producers don't bind queues to the exchange, consumers do.
If you bind the producer first, before a new consumer group, messages will also be lost.
With the RabbitMQ binder, if you know the consumer groups ahead of time, you can set the ...producer.requiredGroups property and the queue(s) will be bound.
See the documentation.
requiredGroups
A comma-separated list of groups to which the producer must ensure message delivery even if they start after it has been created (e.g., by pre-creating durable queues in RabbitMQ).