Spring @Configuration - RabbitMQ Connectivity

I have been playing around with converting an application that I have to use Spring @Configuration mechanism to configure connectivity to RabbitMQ - originally I had the configuration described using an xml bean definition file.

So this was my original configuration:

<beans ...;>

 <context:property-placeholder/>
 <rabbit:connection-factory id="rabbitConnectionFactory" username="${rabbit.user}" host="localhost" password="${rabbit.pass}" port="5672"/>
 <rabbit:template id="amqpTemplate"
      connection-factory="rabbitConnectionFactory"
      exchange="rmq.rube.exchange"
      routing-key="rube.key"
      channel-transacted="true"/>

 <rabbit:queue name="rmq.rube.queue" durable="true"/>

 <rabbit:direct-exchange name="rmq.rube.exchange" durable="true">
  <rabbit:bindings>
   <rabbit:binding queue="rmq.rube.queue" key="rube.key"></rabbit:binding>
  </rabbit:bindings>
 </rabbit:direct-exchange>
</beans>

This is a fairly simple configuration that :

• sets up a connection to a RabbitMQ server,
• creates a durable queue(if not available)
• creates a durable exchange
• and configures a binding to send messages to the exchange to be routed to the queue based on a routing key called "rube.key"

This can be translated to the following @Configuration based java configuration:

@Configuration
public class RabbitConfig {

 @Autowired
 private ConnectionFactory rabbitConnectionFactory;

 @Bean
 DirectExchange rubeExchange() {
  return new DirectExchange("rmq.rube.exchange", true, false);
 }

 @Bean
 public Queue rubeQueue() {
  return new Queue("rmq.rube.queue", true);
 }

 @Bean
 Binding rubeExchangeBinding(DirectExchange rubeExchange, Queue rubeQueue) {
  return BindingBuilder.bind(rubeQueue).to(rubeExchange).with("rube.key");
 }

 @Bean
 public RabbitTemplate rubeExchangeTemplate() {
  RabbitTemplate r = new RabbitTemplate(rabbitConnectionFactory);
  r.setExchange("rmq.rube.exchange");
  r.setRoutingKey("rube.key");
  r.setConnectionFactory(rabbitConnectionFactory);
  return r;
 }
}

This configuration should look much more simpler than the xml version of the configuration. I am cheating a little here though, you should be seeing a missing connectionFactory which is just being injected into this configuration, where is that coming from..this is actually part of a Spring Boot based application and there is a Spring Boot Auto configuration for RabbitMQ connectionFactory based on whether the RabbitMQ related libraries are present in the classpath.

Here is the complete configuration if you are interested in exploring further - https://github.com/bijukunjummen/rg-si-rabbit/blob/master/src/main/java/rube/config/RabbitConfig.java

References:

• Spring-AMQP project here
• Spring-Boot starter project using RabbitMQ here