rabbitmq实现死信队列

所谓的死信队列，也就是我们说的延迟队列。其实现方式就是给普通队列绑定一个所谓的死信队列，给消息设置一个过期时间，在该时间内如果消息没有被消费，那么则会进入死信队列。我这里以Direct模式处理，fanout模式也是类似
下面开始整活。(前提是你已经会基本使用springboot+rabbitmq)

 
            org.springframework.boot
            spring-boot-starter-amqp
        

spring:
  rabbitmq:
    host: 127.0.0.1  #mq服务器ip,默认为localhost
    port: 5672          #mq服务器port,默认为5672
    username: guest     #mq服务器username,默认为gust
    password: guest     #mq服务器password,默认为guest
    virtual-host: /
    #publisher-/confirm/is: true
    #消费消息的时候,就必须手动ack确认,不然消息永远还在队列中
    listener:
      simple:
        acknowledge-mode: manual
      direct:
        acknowledge-mode: manual

基本配置

import org.springframework.amqp.core.Binding;
import org.springframework.amqp.core.BindingBuilder;
import org.springframework.amqp.core.DirectExchange;
import org.springframework.amqp.core.Queue;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import java.util.HashMap;
import java.util.Map;

@Configuration
public class DeadConfig {

    private String normalQueue="normal_queue";
    private String normalExchange="normal_exchange";
    private String normalRoutingKey="normal_routingkey";

    private String deadQueue="dead_queue";
    private String deadExchange="dead_exchange";
    private String deadRoutingKey="dead_routingkey";


    
    @Bean
    Queue normalQueue(){
       // return new Queue(normalQueue);
        Map map = new HashMap<>();
        map.put("x-dead-letter-exchange",deadExchange);
        map.put("x-dead-letter-routing-key", deadRoutingKey);
        return new Queue(normalQueue,true,false,false,map);
    }

    @Bean
    DirectExchange normalExchange(){
        return new DirectExchange(normalExchange);
    }

    @Bean
    Binding normalBindingExchange(){
        return BindingBuilder.bind( normalQueue()).to(normalExchange()).with(normalRoutingKey);
    }

    
    @Bean
    Queue deadQueue(){
        return new Queue(deadQueue);
    }

    @Bean
    DirectExchange deadExchange(){
        return new DirectExchange(deadExchange);
    }

    @Bean
    Binding deadBindingExchange(){
        return BindingBuilder.bind(deadQueue()).to(deadExchange()).with(deadRoutingKey);
    }
}

消息生产者

import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import java.time.LocalDateTime;
import java.util.Arrays;
import java.util.List;

@RestController
@Slf4j
public class RabbitProduct {

    @Autowired
    private RabbitTemplate rabbitTemplate;

    @GetMapping("/123")
    public void mysendDelayMessage() {
        List list = Arrays.asList("123", "456", "789", "899");
        log.info("发送时间:{},发送内容:{}", LocalDateTime.now(), list.toString());
        this.rabbitTemplate.convertAndSend(
                "normal_exchange",
                "normal_routingkey",
                list,
                message -> {
                    message.getMessageProperties().setExpiration("3000");
                    return message;
                }
        );
    }
}

普通队列取消费消息的时候，死信是接收不到的，由于我们这里有对应的队列去消费，所以死信这边是无法获取到消息的

当我们把普通消息队列注释掉之后，也就是不让其消费，等时间到期之后就会转到死信队列中，通过时间差我们就能看出来效果

消费者代码

import com.rabbitmq.client.Channel;
import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.stereotype.Component;

import java.io.IOException;
import java.time.LocalDateTime;
import java.util.List;

@Component
@Slf4j
public class RabbitConsumer {

    
    @RabbitListener(queues = "normal_queue")
    public void normal_queue(List list, Message message, Channel channel) throws IOException {
        log.info("正常队列收到消息时间为:{},收到的消息内容为:{}", LocalDateTime.now(), list.toString());
        channel.basicAck(message.getMessageProperties().getDeliveryTag(), false);
    }

    @RabbitListener(queues = "dead_queue")
    public void myDealy(List list, Message message, Channel channel) throws IOException {
        log.info("死信收到消息时间为:{},收到的消息内容为:{}", LocalDateTime.now(), list.toString());
        channel.basicAck(message.getMessageProperties().getDeliveryTag(), false);
    }
}