Spring AMQP Project with 2 queue's

Question

I'm working on a project that involves 2 queue's, and multiples Listeners interacting with them. Flow:

• New HTTP request comes to the server, then it's converted into a Object that will be the message
• This message has to be published in two queues
• I have two types of Listeners that get messages from each queue and then I do whatever I want

I've been reading and the best way to do is with a fanout-exchange. Here is my code:

listener-configuration.xml

<!-- CREATE CONNECTION FACTORY -->
<rabbit:connection-factory id="connectionFactory"
    host="localhost" username="guest" password="guest" />

<rabbit:admin connection-factory="connectionFactory" />

<!-- <!-- RABBIT QUEUE'S -->
<rabbit:queue id="trashroute.rabbit.queue" name="trashroute.rabbit.queue" auto-delete="false" auto-startup=false
    durable="true" />
<!-- Webapp Queue -->
<rabbit:queue id="trashroute2.rabbit.queue" name="trashroute2.rabbit.queue" auto-delete="false" auto-startup=false
    durable="true" /> 

<!-- CREATE AN EXCHANGE AND BIND THE QUEUE WITH MY.ROUTINGKEY.* TO THE EXCHANGE -->
<rabbit:fanout-exchange id="myExchange" name="trashroute-exchange">
    <rabbit:bindings>
        <rabbit:binding queue="trashroute.rabbit.queue"></rabbit:binding>
        <rabbit:binding queue="trashroute2.rabbit.queue"></rabbit:binding>
    </rabbit:bindings>
</rabbit:fanout-exchange>

<!-- CREATE THE RABBIT TEMPLATES -->
<rabbit:template connection-factory="connectionFactory" exchange="myExchange" queue="trashroute.rabbit.queue"/>
<rabbit:template connection-factory="connectionFactory" exchange="myExchange" queue="trashroute2.rabbit.queue"/>

<!-- INSTANTIATE THE LISTENERS -->
<bean id="persistenceListener" class="trashroute.rabbitmq.listener.PersistenceListener" />
<bean id="webappListener" class="trashroute.rabbitmq.listener.WebappListener" />

<!-- CREATE THE JsonMessageConverter BEAN -->
<bean id="jsonMessageConverter" class="org.springframework.amqp.support.converter.JsonMessageConverter" />

<!-- GLUE THE LISTENER AND QUEUE TO THE LISTENER CONTAINER -->
<rabbit:listener-container id="listenerContainer"
    connection-factory="connectionFactory" message-converter="jsonMessageConverter">
    <rabbit:listener ref="persistenceListener" queues="trashroute.rabbit.queue" />
    <rabbit:listener ref="webappListener" queues="trashroute2.rabbit.queue" />
</rabbit:listener-container>

sender-configuration.xml

<!--  First following line creates a rabbit connection factory with specified parameters -->
<rabbit:connection-factory id="connectionFactory" host="localhost" username="guest" password="guest" />

<!-- Obtain admin rights to create an exchange -->
<rabbit:admin connection-factory="connectionFactory" />

<!-- Create a bean which can send message to trashroute-exchange for the Java program to call -->
<rabbit:template id="template" connection-factory="connectionFactory"  exchange="myExchange"
message-converter="jsonMessageConverter" />


<bean id="rabbitTemplate" class="org.springframework.amqp.rabbit.core.RabbitTemplate">
<property name="connectionFactory" ref="rabbitConnectionFactory"/>
<property name="messageConverter">
    <bean class="org.springframework.amqp.support.converter.JsonMessageConverter"/>
</property>

Listener MainConfiguration.java

@Configuration
public class MainConfiguration {

protected final String persistenceQueue = "trashroute.rabbit.queue";
protected final String webappQueue = "trashroute2.rabbit.queue";

@Bean
public ConnectionFactory connectionFactory() {
    CachingConnectionFactory connectionFactory = new CachingConnectionFactory("localhost");
    connectionFactory.setUsername("guest");
    connectionFactory.setPassword("guest");
    return connectionFactory;
}

@Bean
public AmqpAdmin amqpAdmin() {
    return new RabbitAdmin(connectionFactory());
}

@Bean
public DataController DataController(){
    return new DataController();
}

@Bean
// Every queue is bound to the default direct exchange
public Queue persistenceQueue() { 
    //Create a new queue with an specific name and the durability value in true.
    return new Queue(this.persistenceQueue, true);
}

@Bean
public Queue webappQueue() {
    //Create a new queue with an specific name and the durability value in true.
    return new Queue(this.webappQueue, true);
}
}

Sender MainConfiguration.java

@Configuration
public class SenderConfiguration {

protected final String persistenceQueue = "trashroute.rabbit.queue";
protected final String webappQueue = "trashroute2.rabbit.queue";

//Create the Template
@Bean
public RabbitTemplate rabbitTemplate() {
    RabbitTemplate template = new RabbitTemplate(connectionFactory());
    template.setMessageConverter(new JsonMessageConverter());
    return template;
}

@Bean
public ConnectionFactory connectionFactory() {
    CachingConnectionFactory connectionFactory = new CachingConnectionFactory(
            "localhost");
    connectionFactory.setUsername("guest");
    connectionFactory.setPassword("guest");
    return connectionFactory;
}

@Bean
public IServiceManager scheduledProducer() {
    return new ServiceManagerImpl();
}

@Bean
public BeanPostProcessor postProcessor() {
    return new ScheduledAnnotationBeanPostProcessor();
}

}

Can anyone please tell me what I'm doing wrong? One of the two Listeners, works perfectly, the second never reads a message.

Answer 1

Based on the scenario explained above I have tried to create a sample application which uses Spring Java Config.

Messages are published to trashroute and webapp queues, and respective receivers ( persistence and webapp ) receive the messages.

RabbitConfiguration.java (Contains configuration for both Sender and Receiver)

@Configuration
@EnableRabbit
public class RabbitConfiguration {

    public static final String BROADCAST_TRASHROUTE_QUEUE = "trashroute.rabbit.queue";
    public static final String BROADCAST_WEBAPP_QUEUE = "webapp.rabbit.queue";

    @Bean
    public ConnectionFactory connectionFactory() {
        CachingConnectionFactory connectionFactory =
                new CachingConnectionFactory("localhost");
        return connectionFactory;
    }


    @Bean
    public AmqpAdmin amqpAdmin() {
        return new RabbitAdmin(connectionFactory());
    }

    @Bean
    public Queue trashRouteQueue() {
        return new Queue(BROADCAST_TRASHROUTE_QUEUE);
    }

    @Bean
    public Queue webAppQueue() {
        return new Queue(BROADCAST_WEBAPP_QUEUE);
    }

    @Bean
    public RabbitTemplate rabbitTemplate() {
        RabbitTemplate rabbitTemplate = new RabbitTemplate(connectionFactory());
        return rabbitTemplate;
    }

    @Bean
    public FanoutExchange trashRouteExchange() {
        FanoutExchange exchange = new FanoutExchange("trashroute");
        return exchange;
    }

    @Bean
    public Binding trashRouteBinding() {
        return BindingBuilder.bind(trashRouteQueue()).to(trashRouteExchange());
    }

    @Bean
    public Binding webAppBinding() {
        return BindingBuilder.bind(webAppQueue()).to(trashRouteExchange());
    }

    @Bean
    SimpleMessageListenerContainer persistenceListenerContainer(ConnectionFactory connectionFactory, @Qualifier("persistenceListenerAdapter") MessageListenerAdapter listenerAdapter) {
        SimpleMessageListenerContainer container = new SimpleMessageListenerContainer();
        container.setConnectionFactory(connectionFactory);
        container.setQueues(trashRouteQueue(), webAppQueue());
        container.setMessageListener(listenerAdapter);
        return container;
    }

    @Bean
    MessageListenerAdapter persistenceListenerAdapter(PersistenceListener receiver) {
        return new MessageListenerAdapter(receiver, "receiveMessage");
    }

    @Bean
    SimpleMessageListenerContainer webAppListenerContainer(ConnectionFactory connectionFactory, @Qualifier("webAppListenerAdapter") MessageListenerAdapter listenerAdapter) {
        SimpleMessageListenerContainer container = new SimpleMessageListenerContainer();
        container.setConnectionFactory(connectionFactory);
        container.setQueues(trashRouteQueue(), webAppQueue());
        container.setMessageListener(listenerAdapter);
        return container;
    }

    @Bean
    MessageListenerAdapter webAppListenerAdapter(WebAppListener webAppListener) {
        return new MessageListenerAdapter(webAppListener, "receiveMessage");
    }

    @Bean
    PersistenceListener persistenceListener() {
        return new PersistenceListener();
    }

    @Bean
    WebAppListener webAppListener() {
        return new WebAppListener();
    }

}

PersistenceListener.java

public class PersistenceListener {

    public void receiveMessage(String message) {
        System.out.println("Persistence Listener: Messsage Received <" + message + ">");
    }
}

WebAppListener.java

public class WebAppListener {
    public void receiveMessage(String message) {
        System.out.println("WebAppListener: Message Received <" + message + ">");
    }
}

Application.java

@SpringBootApplication
public class Application implements CommandLineRunner {

    @Autowired
    AnnotationConfigApplicationContext context;

    public static void main(String[] args) throws InterruptedException {
        SpringApplication.run(Application.class, args);
    }

    @Override
    public void run(String... args) throws Exception {
        System.out.println("Waiting five seconds...");
        Thread.sleep(5000);
        System.out.println("Sending message...");

        RabbitTemplate rabbitTemplate = (RabbitTemplate) context.getBean("rabbitTemplate");

        rabbitTemplate.convertAndSend(RabbitConfiguration.BROADCAST_TRASHROUTE_QUEUE, "Hello from trashroute queue!");
        rabbitTemplate.convertAndSend(RabbitConfiguration.BROADCAST_WEBAPP_QUEUE, "Hello from webapp queue!");

        Thread.sleep(10000);
        context.close();
    }
}

Hope this will help. Although you would need to refactor the code if you want to use this in production.