RabbitMQ保证消息的可靠性

一、背景

消息丢失：下图是消息从生产者发送到消费者接收的关系图。通过图片可以看出，消息在生产者、MQ、消费者这三个环节都有可能丢失。

1.1 生产者丢失

• 生产者发送消息时连接MQ失败
• 生产者发送消息到达MQ后未找到Exchange
• 生产者发送消息到达MQ的Exchange后，未找到合适的Queue
• 消息到达MQ后，处理消息的进程发生异常

1.2 MQ丢失

• 消息到达MQ，保存到队列后，尚未消费就突然宕机

1.3 消费者丢失

• 消息接收后尚未处理突然宕机
• 消息接收后处理过程中抛出异常

1.4 总结（三方面入手）

• 确保生产者成功把消息发送到MQ
• 确保MQ不会丢失消息
• 确保消费者成功处理消息

二、解决方案

配置

package com.qiangesoft.rabbitmq.producer;

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

/**
 * 消息发送配置
 *
 * @author qiangesoft
 * @date 2024-05-08
 */
@Configuration
public class MessageConfig {

    public static final String EXCHANGE = "simple.exchange";

    public static final String QUEUE = "simple.queue";

    public static final String ROUTING_KEY = "simple";

    @Bean
    public DirectExchange simpleExchange() {
        return ExchangeBuilder
                .directExchange(EXCHANGE)
                // 持久化交换机
                .durable(true)
                .build();
    }

    @Bean
    public Queue simpleQueue() {
        return QueueBuilder
                // 持久化队列
                .durable(QUEUE)
                // 避免消息堆积、懒加载
                .lazy()
                .build();
    }

    @Bean
    public Binding simpleBinding(Queue simpleQueue, DirectExchange simpleExchange) {
        return BindingBuilder.bind(simpleQueue).to(simpleExchange).with(ROUTING_KEY);
    }

}

2.1 生产者

2.1.1 生产者重试机制

背景：生产者发送消息时，出现了网络故障，导致与MQ的连接中断。
解决方案：配置连接超时时间、重试机制。

spring:
  rabbitmq:    
    # 设置MQ的连接超时时间
    connection-timeout: 1s
    template:
      # 连接重试机制
      retry:
        enabled: true
        # 失败后的初始等待时间
        initial-interval: 1000ms
        # 失败后下次的等待时长倍数，下次等待时长 = initial-interval * multiplier
        multiplier: 1
        # 最大重试次数
        max-attempts: 3

2.1.2 生产者确认机制

背景：

• 生产者发送消息到达MQ后未找到Exchange
• 生产者发送消息到达MQ的Exchange后，未找到合适的Queue
• 消息到达MQ后，处理消息的进程发生异常

解决方案：配置Publisher Confirm机制、Publisher Return机制。

spring:
  rabbitmq:
    # 开启publisher confirm机制，并设置confirm类型，确保消息到达交换机
    publisher-confirm-type: correlated
    # 开启publisher return机制，确保消息到达队列
    publisher-returns: true

定义ConfirmCallback

package com.qiangesoft.rabbitmq.producer;

import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.core.MessageBuilder;
import org.springframework.amqp.core.MessageDeliveryMode;
import org.springframework.amqp.rabbit.connection.CorrelationData;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.util.concurrent.ListenableFutureCallback;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.nio.charset.StandardCharsets;
import java.util.UUID;

/**
 * 生产者
 *
 * @author qiangesoft
 * @date 2024-05-08
 */
@Slf4j
@RequestMapping("/producer")
@RestController
public class ProducerController {

    @Autowired
    public RabbitTemplate rabbitTemplate;

    @GetMapping("/send")
    public void send(String content) {
        CorrelationData correlation = getCorrelationData();

        Message message = MessageBuilder
                .withBody(content.getBytes(StandardCharsets.UTF_8))
                .setMessageId(UUID.randomUUID().toString())
                // 消息持久化
                .setDeliveryMode(MessageDeliveryMode.PERSISTENT)
                .build();

        // 正常发送
        rabbitTemplate.convertAndSend(MessageConfig.EXCHANGE, MessageConfig.ROUTING_KEY, message, correlation);
    }

    private static CorrelationData getCorrelationData() {
        // 异步回调返回回执，开启publisher confirm机制【确保消息到达交换机】
        CorrelationData correlation = new CorrelationData();
        correlation.getFuture().addCallback(new ListenableFutureCallback<>() {
            @Override
            public void onFailure(Throwable ex) {
                log.error("消息发送异常，ID：{}，原因：{}", correlation.getId(), ex.getMessage());
            }

            @Override
            public void onSuccess(CorrelationData.Confirm result) {
                log.info("触发【publisher confirm】机制");
                if (result.isAck()) {
                    log.info("消息发送成功到达交换机，ID：{}", correlation.getId());
                } else {
                    // 消息发送失败
                    log.error("消息发送失败未到达交换机，ID：{}，原因：{}", correlation.getId(), result.getReason());
                }
            }
        });
        return correlation;
    }

}

定义ReturnCallback

package com.qiangesoft.rabbitmq.producer;

import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.core.ReturnedMessage;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.annotation.Configuration;

/**
 * 消息路由失败回退配置
 *
 * @author qiangesoft
 * @date 2024-05-08
 */
@Slf4j
@Configuration
public class ReturnsCallbackConfig implements ApplicationContextAware {

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        RabbitTemplate rabbitTemplate = applicationContext.getBean(RabbitTemplate.class);
        // 消息路由失败退回，设置ReturnsCallback【消息到达交换机没有达到队列】
        rabbitTemplate.setReturnsCallback(new RabbitTemplate.ReturnsCallback() {
            @Override
            public void returnedMessage(ReturnedMessage returned) {
                log.info("触发【publisher return】机制");
                log.error("消息投递失败未到达队列，应答码：{}，原因：{}，交换机：{}，路由键：{}，消息：{}", returned.getReplyCode(), returned.getReplyText(),
                        returned.getExchange(), returned.getRoutingKey(), returned.getMessage());
            }
        });
    }

}

2.2 MQ

• Exchange持久化
• Queue持久化
• Message持久化

2.2.1 Exchange

@Bean
public DirectExchange simpleExchange() {
    return ExchangeBuilder
            .directExchange(EXCHANGE)
            // 持久化交换机
            .durable(true)
            .build();
}

2.2.2 Queue

@Bean
public Queue simpleQueue() {
    return QueueBuilder
            // 持久化队列
            .durable(QUEUE)
            // 避免消息堆积、懒加载
            .lazy()
            .build();
}

2.2.3 Message

Message message = MessageBuilder
                .withBody(content.getBytes(StandardCharsets.UTF_8))
                .setMessageId(UUID.randomUUID().toString())
                // 消息持久化
                .setDeliveryMode(MessageDeliveryMode.PERSISTENT)
                .build();
// 发送
rabbitTemplate.convertAndSend(MessageConfig.EXCHANGE, MessageConfig.ROUTING_KEY, message, correlation);

2.3 消费者

2.3.1 消费者确认机制

spring:
  rabbitmq:
    listener:
      simple:
        # 自动ack
        acknowledge-mode: auto

2.3.2 消费者重试机制

spring:
  rabbitmq:
    listener:
      simple:
        # 消费者失败重试机制
        retry:
          enabled: true
          # 初始的失败等待时长为1秒
          initial-interval: 1000ms
          # 失败的等待时长倍数，下次等待时长 = multiplier * last-interval
          multiplier: 1
          # 最大重试次数
          max-attempts: 3
          # true无状态；false有状态。如果业务中包含事务，这里改为false
          stateless: true

2.3.3 失败处理策略

package com.qiangesoft.rabbitmq.consumer;

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.amqp.rabbit.core.RabbitTemplate;
import org.springframework.amqp.rabbit.retry.MessageRecoverer;
import org.springframework.amqp.rabbit.retry.RepublishMessageRecoverer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * 消息消费失败配置
 * ps：配置处理失败消息的交换机和队列
 *
 * @author qiangesoft
 * @date 2024-05-08
 */
@Configuration
public class ErrorMessageConfig {

    public static final String EXCHANGE = "error.exchange";

    public static final String QUEUE = "error.queue";

    public static final String ROUTING_KEY = "error";

    @Bean
    public DirectExchange errorMessageExchange() {
        return new DirectExchange(EXCHANGE);
    }

    @Bean
    public Queue errorQueue() {
        return new Queue(QUEUE, true);
    }

    @Bean
    public Binding errorBinding(Queue errorQueue, DirectExchange errorMessageExchange) {
        return BindingBuilder.bind(errorQueue).to(errorMessageExchange).with(ROUTING_KEY);
    }

    @Bean
    public MessageRecoverer republishMessageRecoverer(RabbitTemplate rabbitTemplate) {
        return new RepublishMessageRecoverer(rabbitTemplate, EXCHANGE, ROUTING_KEY);
    }

}