10.回退消息

rabbitmq回退消息

mandatory参数

在仅开启了生产者确认机制的情况下，交换机接收到消息后，会直接给消息生产者发送确认消息，如果发现该消息不可路由，那么消息会被直接丢弃，此时生产者是不知道消息被丢弃这件事情的。

可以通过设置mandatory参数在当消息传递过程中不可达目的地时将消息返回给生产者。

案例演示

添加application.properties配置文件

server.port=8080

spring.rabbitmq.host=172.16.140.133
spring.rabbitmq.port=5672
spring.rabbitmq.username=admin
spring.rabbitmq.password=123456

spring.rabbitmq.publisher-confirm-type=correlated

添加配置类

/** * 回退消息配置类 */
@Configuration
public class ConfirmConfig {
    

    public static final String CONFIRM_EXCHANGE = "confirm.exchange";
    public static final String CONFIRM_QUEUE_NAME = "confirm.queue";


    @Bean("confirmExchange")
    public DirectExchange confirmExchange(){
    
        return new DirectExchange(CONFIRM_EXCHANGE);
    }

    @Bean("confirmQueue")
    public Queue confirmQueue(){
    
        return QueueBuilder.durable(CONFIRM_QUEUE_NAME).build();
    }

    @Bean
    public Binding queueBinding(@Qualifier("confirmQueue") Queue queue,@Qualifier("confirmExchange") DirectExchange exchange){
    
        return BindingBuilder.bind(queue).to(exchange).with("key1");
    }

}

添加回调接口

/** * 消息回退回调接口 */
@Component
@Slf4j
public class MyCallBack implements RabbitTemplate.ConfirmCallback,RabbitTemplate.ReturnsCallback {
    


    @Override
    public void confirm(CorrelationData correlationData, boolean ack, String cause) {
    
        String id = correlationData != null ? correlationData.getId():"";
        if (ack){
    
            log.info("交换机已经收到id为:{}的消息",id);
        }else {
    
            log.info("交换机还未收到id为：{}的消息，由于原因：{}",id ,cause);
        }
    }

    @Override
    public void returnedMessage(ReturnedMessage returned) {
    
        log.info("消息：{}被服务器退回，退回原因：{},交换机是：{}，路由key：{}",new String(returned.getMessage().getBody()),returned.getReplyText(),returned.getExchange(),returned.getRoutingKey());
    }
}

添加消费者

/** * 消息消费者 */
@Component
@Slf4j
public class ConfirmConsumer {
    
    public static final String CONFIRM_QUEUE_NAME = "confirm.queue";

    @RabbitListener(queues = CONFIRM_QUEUE_NAME)
    public void receiveMsg(Message message){
    
        String msg = new String(message.getBody());
        log.info("接收到队列confirm.queue消息：{}",msg);
    }
}

添加生产者

/** * 消息生产者 */
@RestController
@RequestMapping("/confirm")
@Slf4j
public class ProducerController {
    
    public static final String CONFIRM_EXCHANGE_NAME = "confirm.exchange";

    @Autowired
    private RabbitTemplate rabbitTemplate;

    @Autowired
    private MyCallBack myCallBack;

    /** * 初始化rabbitTemplate */
    @PostConstruct
    public void init(){
    
        rabbitTemplate.setConfirmCallback(myCallBack);
        /** * true：交换机无法将消息进行路由时，会讲该消息返回给生产者 * false：如果发现消息无法进行路由，则直接丢弃 */
        rabbitTemplate.setMandatory(true);

        rabbitTemplate.setReturnsCallback(myCallBack);
    }



    @GetMapping("sendMessage/{message}")
    public void sendMessage(@PathVariable String message){
    
        CorrelationData correlationData = new CorrelationData("1");
        String routingKey = "key1";

        rabbitTemplate.convertAndSend(CONFIRM_EXCHANGE_NAME,routingKey,message+routingKey,correlationData);

        CorrelationData correlationData2 = new CorrelationData("2");
        String routingKey2 = "key2";
        rabbitTemplate.convertAndSend(CONFIRM_EXCHANGE_NAME,routingKey2,message+routingKey,correlationData2);

        log.info("发送消息内容：{}",message);
    }
}

结果