【初始RabbitMQ】高级发布确认的实现

在生产环境中由于一些不明原因，导致 rabbitmq 重启，在 RabbitMQ 重启期间生产者消息投递失败，导致消息丢失，需要手动处理和恢复。于是，我们开始思考，如何才能进行 RabbitMQ 的消息可靠投递呢？特别是在这样比较极端的情况，RabbitMQ 集群不可用的时候，无法投递的消息该如何处理呢

发布确认SpringBoot版本

确认机制方案

代码架构图

配置文件

spring.rabbitmq.host=118.31.6.132
spring.rabbitmq.port=5672
spring.rabbitmq.username=admin
spring.rabbitmq.password=123
spring.rabbitmq.publisher-confirm-type=correlated

在配置文件当中需要添加 spring.rabbitmq.publisher-confirm-type=correlated

NONE 禁用发布确认模式，是默认值
CORRELATED 发布消息成功到交换器后会触发回调方法
SIMPLE 经测试有两种效果，其一效果和 CORRELATED 值一样会触发回调方法，其二在发布消息成功后使用 rabbitTemplate 调用 waitForConfirms 或 waitForConfirmsOrDie 方法等待 broker 节点返回发送结果，根据返回结果来判定下一步的逻辑，要注意的点是 waitForConfirmsOrDie 方法如果返回 false 则会关闭 channel，则接下来无法发送消息到 broker

引入依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>3.2.2</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.example</groupId>
	<artifactId>springboot-rabbitmq</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>demo</name>
	<description>Demo project for Spring Boot</description>
	<properties>
		<java.version>17</java.version>
	</properties>
	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-amqp</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		<dependency>
			<groupId>org.projectlombok</groupId>
			<artifactId>lombok</artifactId>
			<optional>true</optional>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>org.springframework.amqp</groupId>
			<artifactId>spring-rabbit-test</artifactId>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-autoconfigure</artifactId>
			<version>3.2.0</version>
		</dependency>
	</dependencies>
	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>

</project>

添加配置类

package com.example.config;

import org.springframework.amqp.core.*;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class ConfirmConfig {
    public static final String CONFIRM_EXCHANGE_NAME = "confirm.exchange";
    public static final String CONFIRM_QUEUE_NAME = "confirm.queue";
    //声明确认队列
    @Bean
    public Queue confirmQueue(){
        return QueueBuilder.durable(CONFIRM_QUEUE_NAME).build();
    }
    //声明确认交换机
    @Bean
    public DirectExchange confirmExchange(){
        return new DirectExchange(CONFIRM_EXCHANGE_NAME);
    }
    //声明确认队列绑定关系
    @Bean
    public Binding queueBinding(@Qualifier("confirmQueue")Queue queue,
                                @Qualifier("confirmExchange")DirectExchange directExchange){
        return BindingBuilder.bind(queue).to(directExchange).with("key1");
    }
}

回调接口

package com.example.component;

import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.rabbit.connection.CorrelationData;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.stereotype.Component;

@Component
@Slf4j
public class MyCallBack implements RabbitTemplate.ConfirmCallback {
    /**
     * 交换机不管是否收到消息的一个回调方法
     * CorrelationData
     * 消息相关数据
     * ack
     * 交换机是否收到消息
     */
    @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:{}消息,由于原因:{}",id,cause);
        }
    }
}

消息生产者

package com.example.controller;

import com.example.component.MyCallBack;
import jakarta.annotation.PostConstruct;
import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.rabbit.connection.CorrelationData;
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.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/confirm")
@Slf4j
public class producer {
    public static final String CONFIRM_EXCHANGE_NAME = "confirm.exchange";
    @Autowired
    private RabbitTemplate rabbitTemplate;
    @Autowired
    private MyCallBack myCallBack;
    @PostConstruct //在类实例被创建后（通过依赖注入完成，并且在任何其他初始化方法之前），容器会自动调用这个方法
    public void init(){
        rabbitTemplate.setConfirmCallback(myCallBack);
    }
    @GetMapping("/sendMessage/{message}")
    public void sendMessage(@PathVariable String message){
        //指定消息id为1
        CorrelationData correlationData1 = new CorrelationData("1");
        String routingKey = "key1";
        rabbitTemplate.convertAndSend(CONFIRM_EXCHANGE_NAME,routingKey,
                message+routingKey,correlationData1);
        log.info("发送消息内容:{}",message+routingKey);
        CorrelationData correlationData2 = new CorrelationData("2");
        routingKey = "key2";
        rabbitTemplate.convertAndSend(CONFIRM_EXCHANGE_NAME,routingKey,
                message+routingKey,correlationData2);
        log.info("发送消息内容:{}",message+routingKey);
    }
}

消息消费者

package com.example.component;

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

@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("接受到队列 confirm.queue 消息:{}",msg);
    }
}

结果分析

访问：http://127.0.0.1:8080/confirm/sendMessage/%E4%BD%A0%E5%A5%BD

可以看到，发送了两条消息，第一条消息的 RoutingKey 为 "key1"，第二条消息的 RoutingKey 为 "key2"，两条消息都成功被交换机接收，也收到了交换机的确认回调，但消费者只收到了一条消息，因为第二条消息的 RoutingKey 与队列的 BindingKey 不一致，也没有其它队列能接收这个消息，所有第二条消息被直接丢弃了

回退消息

Mandatory参数

在仅开启了生产者确认机制的情况下，交换还击接收到消息之后，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个事件的。那么如何让无法被路由的消息帮我想办法处理一下？最起码通知我一声，我好自己处理啊。通过设置 mandatory 参数可以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

消息生产者代码

package com.example.controller;

import jakarta.annotation.PostConstruct;
import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.core.ReturnedMessage;
import org.springframework.amqp.rabbit.connection.CorrelationData;
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.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.UUID;

@RestController
@Slf4j
@RequestMapping("/confirm")
public class MessageProducer implements RabbitTemplate.ConfirmCallback
        ,RabbitTemplate.ReturnsCallback{
    @Autowired
    private RabbitTemplate rabbitTemplate;
    @PostConstruct
    private void init(){
        rabbitTemplate.setConfirmCallback(this);
        /**
         * true：交换机无法将消息进行路由时，会将消息返回给生产者
         * false：如果发现纤细无法进行路由时，直接的丢弃
         */
        rabbitTemplate.setMandatory(true);
        //设置回退消息给谁处理
        rabbitTemplate.setReturnsCallback(this);
    }
    @GetMapping("/sendMessage/{message}")
    public void sendMessage(@PathVariable String message){
        //让消息绑定一个id值
        CorrelationData correlationData1 = new CorrelationData(UUID.randomUUID().toString());
        rabbitTemplate.convertAndSend("confirm.exchange","key1"
                ,message+"key1",correlationData1);
        log.info("发送消息 id 为:{}内容为{}",correlationData1.getId(),message+"key1");
        CorrelationData correlationData2 = new CorrelationData(UUID.randomUUID().toString());

        rabbitTemplate.convertAndSend("confirm.exchange","key2",message+"key2",correlationData2)
        ;
        log.info("发送消息 id 为:{}内容为{}",correlationData2.getId(),message+"key2");
    }
    @Override
    public void confirm(CorrelationData correlationData,boolean ack,String cause){
        String id = correlationData != null ? correlationData.getId() : "";
        if (ack) {
            log.info("交换机收到消息确认成功, id:{}", id);
        } else {
            log.error("消息 id:{}未成功投递到交换机,原因是:{}", id, cause);
        }
    }
    @Override
    public void returnedMessage(ReturnedMessage returnedMessage) {
        log.info("消息:{}被服务器退回，退回原因:{}, 交换机是:{}, 路由 key:{}",
                new String(returnedMessage.getMessage().getBody()),returnedMessage.getReplyText()
                ,returnedMessage.getExchange(), returnedMessage.getRoutingKey());
    }
}

回调接口

package com.example.component;

import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.core.ReturnedMessage;
import org.springframework.amqp.rabbit.connection.CorrelationData;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.stereotype.Component;

@Component
@Slf4j
public class MyCallBack implements RabbitTemplate.ConfirmCallback
        ,RabbitTemplate.ReturnsCallback{
    /**
     * 交换机不管是否收到消息的一个回调方法
     * CorrelationData
     * 消息相关数据
     * ack
     * 交换机是否收到消息
     */
    @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:{}消息,由于原因:{}",id,cause);
        }
    }
    @Override
    public void returnedMessage(ReturnedMessage returnedMessage) {
        log.info("消息:{}被服务器退回，退回原因:{}, 交换机是:{}, 路由 key:{}",
                new String(returnedMessage.getMessage().getBody()),returnedMessage.getReplyText()
                ,returnedMessage.getExchange(), returnedMessage.getRoutingKey());
    }
}

消息消费者

package com.example.component;

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

@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("接受到队列 confirm.queue 消息:{}",msg);
    }
}

结果分析

备份交换机

备份交换机是 RabbitMQ 中的一个机制，用于处理无法被路由到队列的消息。它可以看作是交换机的“备胎”，当交换机接收到无法路由的消息时，会将这些消息转发到备份交换机中，由备份交换机来进行处理

通常情况下，备份交换机的类型是 Fanout，这意味着它会将所有接收到的消息广播给与其绑定的所有队列。因此，当备份交换机接收到无法路由的消息时，这些消息会被发送到与备份交换机绑定的队列中

通过设置备份交换机，我们可以将无法被路由的消息存储到一个特定的队列中，然后可以通过监控这个队列来进行报警或者手动处理。这样做既可以避免丢失消息，又不会增加生产者的复杂性，同时也提高了系统的稳定性和可靠性

代码架构图

修改配置类

package com.example.config;

import org.springframework.amqp.core.*;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class ConfirmConfig {
    public static final String CONFIRM_EXCHANGE_NAME = "confirm.exchange";
    public static final String CONFIRM_QUEUE_NAME = "confirm.queue";
    public static final String BACKUP_EXCHANGE_NAME = "backup.exchange";
    public static final String BACKUP_QUEUE_NAME = "backup.queue";
    public static final String WARNING_QUEUE_NAME = "warning.queue";
    //声明确认队列
    @Bean
    public Queue confirmQueue() {
        return QueueBuilder.durable(CONFIRM_QUEUE_NAME).build();
    }
    //声明确认队列绑定关系
    @Bean
    public Binding queueBinding(@Qualifier("confirmQueue")Queue queue,
                                @Qualifier("confirmExchange")DirectExchange directExchange){
        return BindingBuilder.bind(queue).to(directExchange).with("key1");
    }
    //声明备份交换机
    @Bean
    public FanoutExchange backupExchange(){
        return new FanoutExchange(BACKUP_EXCHANGE_NAME);
    }
    //声明确认交换机并且绑定备份交换机
    @Bean
    public DirectExchange confirmExchange(){
        ExchangeBuilder exchangeBuilder = ExchangeBuilder.directExchange(CONFIRM_EXCHANGE_NAME)
                .durable(true)
                //设置该交换机的备用交换机
                .withArgument("alternate-exchange", BACKUP_EXCHANGE_NAME);
        return (DirectExchange) exchangeBuilder.build();
    }
    //声明警告队列
    @Bean
    public Queue warningQueue(){
        return QueueBuilder.durable(WARNING_QUEUE_NAME).build();
    }
    // 声明报警队列绑定关系
    @Bean
    public Binding warningBinding(@Qualifier("warningQueue") Queue queue,
                                  @Qualifier("backupExchange") FanoutExchange
                                          backupExchange){
        return BindingBuilder.bind(queue).to(backupExchange);
    }
    // 声明备份队列
    @Bean("backQueue")
    public Queue backQueue(){
        return QueueBuilder.durable(BACKUP_QUEUE_NAME).build();
    }
    // 声明备份队列绑定关系
    @Bean
    public Binding backupBinding(@Qualifier("backQueue") Queue queue,
                                 @Qualifier("backupExchange") FanoutExchange backupExchange){
        return BindingBuilder.bind(queue).to(backupExchange);
    }
}

报警消费者

package com.example.controller;

import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.web.bind.annotation.RestController;

@RestController
@Slf4j
public class WarningConsumer {
    public static final String WARNING_QUEUE_NAME = "warning.queue";

    @RabbitListener(queues = WARNING_QUEUE_NAME)
    public void receiveWarningMsg(Message message) {
        String msg = new String(message.getBody());
        log.error("报警发现不可路由消息：{}", msg);
    }
}