Rabbitmq 实现延时任务

1、需要用到插件 rabbitmq_delayed_message_exchange 来实现，插件下载地址：https://www.rabbitmq.com/community-plugins.html

2、下载后把插件放到 plugins 里面，然后到 sbin里面打开cmd，执行 rabbitmq-plugins enable rabbitmq_delayed_message_exchange 命令

3、插件装好后，重新启动mq，然后集成mq。

　　首先，导包

　　　　<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>

　　

　　然后，配置文件配置连接信息：

spring.rabbitmq.host=127.0.0.1
spring.rabbitmq.port=5672
spring.rabbitmq.username=guest
spring.rabbitmq.password=guest
spring.rabbitmq.listener.simple.acknowledge-mode=manual

　　

　　mq 配置：

　　

package com.rrg.gz.mq;

import org.springframework.amqp.core.Binding;
import org.springframework.amqp.core.BindingBuilder;
import org.springframework.amqp.core.CustomExchange;
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;

/**
 *  mq配置
 * @author huangsz  2019/4/25 0025
 */
@Configuration
public class RabbitPluginConfig {

    /**
     * 延时队列交换机
     * 注意这里的交换机类型：CustomExchange
     * @return
     */
    @Bean
    public CustomExchange delayExchange(){
        Map<String, Object> args = new HashMap<>();
        args.put("x-delayed-type", "direct");
        return new CustomExchange("rrg_delay_exchange","x-delayed-message",true, false,args);
    }

    /**
     * 延时队列
     * @return
     */
    @Bean
    public Queue delayQueue(){
        return new Queue("rrg_delay_queue",true);
    }

    /**
     * 给延时队列绑定交换机
     * @return
     */
    @Bean
    public Binding cfgDelayBinding(Queue cfgDelayQueue, CustomExchange cfgUserDelayExchange){
        return BindingBuilder.bind(cfgDelayQueue).to(cfgUserDelayExchange).with("rrg_delay_key").noargs();
    }
}

　　发送消息类、接收类和信息类，信息类是我们自己时间业务封装需要消费的信息。

package com.rrg.gz.mq;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

/**
 * 消息发送者
 *
 * @author huangsz  2019/3/7 0007
 */
@Component
public class Sender {
    private static Logger log = LoggerFactory.getLogger(Sender.class);

    @Autowired
    private RabbitTemplate rabbitTemplate;

    public void sendDelayMessage(MqEntity entity, long time) {
        // 这里的消息可以是任意对象，无需额外配置，直接传即可
        log.info("延时队列生产消息");
        this.rabbitTemplate.convertAndSend(
                "rrg_delay_exchange",
                "rrg_delay_key",
                entity,
                message -> {
                    // 注意这里时间可以使long，而且是设置header
                    message.getMessageProperties().setHeader("x-delay",time);
                    return message;
                }
        );
        log.info("{}ms后执行", time);
    }

}

package com.rrg.gz.mq;

import com.rabbitmq.client.Channel;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

/**
 * 接受者
 *
 * @author huangsz  2019/3/7 0007
 */

@Component
public class Receiver {
    private static Logger log = LoggerFactory.getLogger(Receiver.class);
    @Autowired
    private Sender sender;

    @RabbitListener(queues = "rrg_delay_queue")
    public void cfgUserReceiveDealy(MqEntity entity, Message message, Channel channel) throws Exception{
        log.info("开始接受消息！");
        // 通知 MQ 消息已被接收,可以ACK(从队列中删除)了
        channel.basicAck(message.getMessageProperties().getDeliveryTag(), false);
        System.out.println("接收消息并打印");
        System.out.println(entity);
    }
}

package com.rrg.gz.mq;

import java.io.Serializable;

/**
 *  一定要实现 Serializable
 * @author huangsz  2019/3/7 0007
 */
public class MqEntity implements Serializable {

    private Integer userId;
    private String msg;

    public MqEntity() {
    }

    public MqEntity(Integer userId, String msg) {
        this.userId = userId;
        this.msg = msg;
    }

    public Integer getUserId() {
        return userId;
    }

    public void setUserId(Integer userId) {
        this.userId = userId;
    }

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }

    @Override
    public String toString() {
        return "MqEntity{" +
                "userId=" + userId +
                ", msg='" + msg + '\'' +
                '}';
    }
}

4、写一个controller测试：

　　

@RequestMapping("/test1")
    public void test(){
        MqEntity mqEntity = new MqEntity(1,"30秒后消费");
        sender.sendDelayMessage(mqEntity,30000);
    }

    @RequestMapping("/test2")
    public void test2(){
        MqEntity mqEntity = new MqEntity(1,"10秒后消费");
        sender.sendDelayMessage(mqEntity,10000);
    }

先执行test1，然后执行test2,这个时候，不需要等test1消费完之后，test2才消费信息。