Spring Cloud Streaming - Separate Connection for Producer & Consumer

Question

I have a Spring Cloud Streaming transformer application using RabbitMQ. It is reading from a Rabbit queue, doing some transformation, and writing to a Rabbit exchange. I have my application deployed to PCF and am binding to a Rabbit service.

This works fine, but now I am needing a separate connection for consuming and producing the message. (I want to read from the Rabbit queue using one connection, and write to a Rabbit exchange using a different connection). How would I configure this? Is it possible to bind my applications to 2 different Rabbit services using 1 as the producer and 1 as the consumer?

Artem Bilan Artem Bilan · Accepted Answer · 2017-10-04T17:14:39

Well, starting with version 1.3 Rabbit Binder indeed creates a separate ConnectionFactory for producers: https://docs.spring.io/spring-cloud-stream/docs/Ditmars.RELEASE/reference/htmlsingle/#_rabbitmq_binder

Starting with version 1.3, the RabbitMessageChannelBinder creates an internal ConnectionFactory copy for the non-transactional producers to avoid dead locks on consumers when shared, cached connections are blocked because of Memory Alarm on Broker.

So, maybe that is just enough for you as is after upgrading to Spring Cloud Stream Ditmars.

UPDATE

How would I go about configuring this internal ConnectionFactory copy with different connection properties?

No, that's different story. What you need is called multi-binder support: https://docs.spring.io/spring-cloud-stream/docs/Ditmars.RELEASE/reference/htmlsingle/#multiple-binders

You should declare several blocks for different connection factories:

spring.cloud.stream.bindings.input.binder=rabbit1
spring.cloud.stream.bindings.output.binder=rabbit2

...

spring:
  cloud:
    stream:
      bindings:
        input:
          destination: foo
          binder: rabbit1
        output:
          destination: bar
          binder: rabbit2
      binders:
        rabbit1:
          type: rabbit
          environment:
            spring:
              rabbitmq:
                host: <host1>
        rabbit2:
          type: rabbit
          environment:
            spring:
              rabbitmq:
                host: <host2>

Spring Cloud Streaming - Separate Connection for Producer & Consumer

1 Answers