RabbitMq 实现延时队列-Springboot版本

rabbitmq本身没有实现延时队列，但是可以通过死信队列机制，自己实现延时队列；

原理：当队列中的消息超时成为死信后，会把消息死信重新发送到配置好的交换机中，然后分发到真实的消费队列；

步骤：

1、创建带有时限的队列 dealLineQueue;

2、创建死信Faout交换机dealLineExchange;

3、创建消费队列realQueue，并和dealLineExchange绑定

4、配置dealLineQueue 的过期时间，消息过期后的死信交换机，重发的routing-key；

以下以springboot为例子贴出代码

项目结构：

基本值-DealConstant

package com.eyjian.rabbitmq.dealline;

public interface DealConstant {

    String DEAL_LINE_QUEUE = "dealLineQueue";

    String DEAL_LINE_EXCHANGE = "dealLineExchange";

    String REAL_QUEUE= "realQueue";

}

消费者Lister

package com.eyjian.rabbitmq.dealline;

import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.stereotype.Component;

/**
 * 死信队里模拟延时队列
 * @Author: yeyongjian
 * @Date: 2019-05-18 14:12
 */
@Component
public class Lister {
    @RabbitListener(queues = DealConstant.REAL_QUEUE)
    public void handle(Message message){
        byte[] body = message.getBody();
        String msg = new String(body);
        System.out.println(msg);

    }
}

配置类RabbitmqConfig

package com.eyjian.rabbitmq.dealline;

import com.rabbitmq.client.Channel;
import org.springframework.amqp.core.Binding;
import org.springframework.amqp.core.BindingBuilder;
import org.springframework.amqp.core.FanoutExchange;
import org.springframework.amqp.core.Queue;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

@Configuration
public class RabbitmqConfig {
    @Autowired
    private RabbitTemplate rabbitTemplate;

    //启动初始化删除绑定用的
//    @PostConstruct
    public void delete() throws IOException {
        Channel channel = rabbitTemplate.getConnectionFactory().createConnection().createChannel(true);
        channel.queueUnbind(DealConstant.REAL_QUEUE,DealConstant.DEAL_LINE_EXCHANGE,"");
    }
    @Bean
    public Queue initDealLineQueue() {
        Map<String, Object> args = new HashMap<>();
        args.put("x-dead-letter-exchange", DealConstant.DEAL_LINE_EXCHANGE);
        args.put("x-dead-letter-routing-key", DealConstant.DEAL_LINE_QUEUE);//超时转发的队列
        args.put("x-message-ttl", 5000);//延时时间
        Queue queue = new Queue(DealConstant.DEAL_LINE_QUEUE,true,false,false,args);
        return queue;
    }
    @Bean
    FanoutExchange dealLineExchange() {
        return new FanoutExchange(DealConstant.DEAL_LINE_EXCHANGE);
    }
    @Bean
    Binding bindingiVewUgcTopicExchange(Queue initRealQueue, FanoutExchange dealLineExchange) {
        return BindingBuilder.bind(initRealQueue).to(dealLineExchange);
    }
    @Bean
    public Queue initRealQueue() {
        return new Queue(DealConstant.REAL_QUEUE);
    }

}

application.properties文件

spring.rabbitmq.addresses=localhost
spring.rabbitmq.host=5672
spring.rabbitmq.username=guest
spring.rabbitmq.password=guest

项目启动后，rabbitmq控制台信息如下：

test类发送消息

package com.eyjian.rabbitmq;

import com.eyjian.rabbitmq.dealline.DealConstant;
import com.rabbitmq.client.Channel;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import java.io.IOException;

@RunWith(SpringRunner.class)
@SpringBootTest
public class RabbitmqLearnApplicationTests {

    @Autowired
    RabbitTemplate rabbitTemplate;
    @Test
    public void contextLoads() throws IOException {
        rabbitTemplate.convertAndSend(DealConstant.DEAL_LINE_QUEUE,"hell word");
    }

}

5秒后控制台打印消息

源码地址：https://github.com/hd-eujian/rabbitmq-learn.git

原文地址：https://www.cnblogs.com/yeyongjian/p/10886347.html