RabbitMQ request/response "RabbitTemplate is not configured as listener"

Question

我正在使用 Spring-AMQP rabbitmq 实现测试 request/response 模式，但我无法让它工作...

我配置了以下工件：

test_exchange 有问候队列。路由键 = greeting
reply_exchange 有回复队列。路由键 = 回复

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

@Bean
public Queue greeting() {
    return new Queue("greeting");
}

@Bean
public Queue replies() {
    return new Queue("replies");
}

MessageListener receiver() {
    return new MessageListenerAdapter(new RabbitMqReceiver(), "onMessage");
}

@Bean
public RabbitTemplate rabbitTemplate(ConnectionFactory connectionFactory, Queue replies) {
    RabbitTemplate template = new RabbitTemplate(connectionFactory);
    template.setExchange("test_exchange");
    template.setRoutingKey("greeting");     
    template.setReplyAddress("reply_exchange"+"/"+replies.getName());
    template.setReplyTimeout(60000);
    return template;
}

@Bean
public SimpleMessageListenerContainer replyContainer(ConnectionFactory connectionFactory, 
        RabbitTemplate rabbitTemplate, Queue replies) {
    SimpleMessageListenerContainer container = new SimpleMessageListenerContainer();
    container.setConnectionFactory(connectionFactory);
    container.setMessageListener(rabbitTemplate);
    container.setQueues(replies);
    return container;
}

@Bean
public SimpleMessageListenerContainer serviceListenerContainer(
        ConnectionFactory connectionFactory) {
    SimpleMessageListenerContainer container = new SimpleMessageListenerContainer();
    container.setConnectionFactory(connectionFactory);
    container.setQueues(greeting());
    container.setMessageListener(receiver());
    return container;
}

我正在按照 github 上的示例进行操作，但它崩溃了：

Caused by: java.lang.IllegalStateException: RabbitTemplate is not configured as MessageListener - cannot use a 'replyAddress': reply_exchange/replies

文档说：

Starting with version 1.5, the RabbitTemplate will detect if it has been configured as a MessageListener to receive replies. If not, attempts to send and receive messages with a reply address will fail with an IllegalStateException (because the replies will never be received).

这很好，但是 RabbitTemplate 是怎么做到的呢？它如何检测是否配置为 MessageListener？

提前致谢

PS: 发送码:

public void send() {
    Message message = MessageBuilder.withBody("Payload".getBytes())
            .setContentType("text/plain")
            .build();
    Message reply = this.template.sendAndReceive(message);
    System.out.println("Reply from server is: "+new String(reply.getBody()));
}

Answer 1

当回复容器启动时，它检测到模板是 ListenerContainerAware 并调用 expectedQueueNames() 来检索回复队列（如果 replyAddress 的格式为 exch/rk，则为 null）；如果返回非空结果，则容器检查队列是否正确；如果 exch/rk 是回复地址，你会得到这个

logger.debug("Cannot verify reply queue because it has the form 'exchange/routingKey'");

此方法无条件设置 isListener 布尔值，从而避免了该异常。所以看起来容器在您发送消息之前还没有启动 - 您是在上下文完全初始化之前发送吗？

请注意，由于 RabbitMQ 实现了直接回复，通常不再需要使用回复容器（除非您想要 HA 回复队列或出于其他原因需要显式回复队列）。直接回复消除了驱使我们实施回复容器机制的性能问题。

Answer 2

加里，你的直觉一如既往的完美。

我更改了我的发送代码：

@SpringBootApplication
public class App 
{
    @Bean(initMethod="send")
    public RabbitMqSender sender() {
        final RabbitMqSender sender = new RabbitMqSender();
        return sender;
    }

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

}

至：

@SpringBootApplication
public class App 
{   
public static void main(String[] args) throws Exception {
    final ConfigurableApplicationContext configAppContext =   SpringApplication.run(App.class, args);
    final RabbitMqSender sender = configAppContext.getBean(RabbitMqSender.class);
    sender.send();
}

}

确保在所有 bean 都准备就绪时发送，request/response 效果非常好！

是的，我一定会尝试 Direct-TO 模式。

谢谢加里的帮助。

问候

托马斯

RabbitMQ request/response "RabbitTemplate is not configured as listener"

RabbitMQ request/response "RabbitTemplate is not configured as listener"

rabbitmq

spring-rabbit