springboot-rabbitmq-ACK防止信息在生产端或消费端丢失

application.yum关键配置

spring:
  rabbitmq:
    host: 127.0.0.1
    username: cloud-dev
    password: cloud-dev
    port: 5672
    virtual-host: /
    listener:
      simple:
        concurrency: 10 # Minimum number of consumers.
        max-concurrency: 20 # Maximum number of consumers.
        prefetch: 50
        retry:
          enabled: true #是否开启消费者重试（为false时关闭消费者重试，这时消费端代码异常会一直重复收到消息）
          max-attempts: 3
          initial-interval: 5000ms
        default-requeue-rejected: true  #默认true 重试次数超过上面的设置之后是否丢弃（false不丢弃时需要写相应代码将该消息加入死信队列）
        acknowledge-mode: manual        #关键    消费方手动ack
      direct:
        acknowledge-mode: manual        #关键    消费方手动ack
    publisher-returns: true             #关键    发送方的return与confirm模式保证信息发出成功
    publisher-confirms: true            #关键    发送方的return与confirm模式保证信息发出成功

生产者类

import java.util.UUID;

import javax.annotation.PostConstruct;

import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.amqp.rabbit.core.RabbitTemplate.ReturnCallback;
import org.springframework.amqp.rabbit.support.CorrelationData;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

@Component
public class Sender implements RabbitTemplate.ConfirmCallback, ReturnCallback {
    
    @Autowired
    private RabbitTemplate rabbitTemplate;
    
    @PostConstruct
    public void init() {
        rabbitTemplate.setConfirmCallback(this);
        rabbitTemplate.setReturnCallback(this);
    }

    @Override
    public void confirm(CorrelationData correlationData, boolean ack, String cause) {
        if (ack) {  
            System.out.println("消息发送成功:" + correlationData);  
        } else {  
            System.out.println("消息发送失败:" + cause);  
        }  
        
    }

    //通过实现ReturnCallback接口，如果消息从交换器发送到对应队列失败时触发（比如根据发送消息时指定的routingKey找不到队列时会触发）
	@Override
	public void returnedMessage(Message message, int replyCode, String replyText, String exchange, String routingKey) {
        System.out.println("消息主体message: " + message);
		System.out.println("消息主体message: " + replyCode);
		System.out.println("描述: " + replyText);
		System.out.println("消息使用的交换器exchange: " + exchange);
		System.out.println("消息使用的路由键routing: " + routingKey);
	}

    //发送消息，不需要实现任何接口，供外部调用。
    public void send(String msg){
        
        CorrelationData correlationId = new CorrelationData(UUID.randomUUID().toString());
        
        System.out.println("开始发送消息 : " + msg.toLowerCase());
        String response = rabbitTemplate.convertSendAndReceive("topicExchange", "key.1", msg, correlationId).toString();
        System.out.println("结束发送消息 : " + msg.toLowerCase());
        System.out.println("消费者响应 : " + response + " 消息处理完成");
    }
}

消费者

@RabbitListener(queues = "hello")
public void process(String hello, Channel channel, Message message) throws IOException 
{
        System.out.println("HelloReceiver收到  : " + hello +"收到时间"+new Date());
        try {
            //告诉服务器收到这条消息 已经被我消费了 可以在队列删掉 这样以后就不会再发了 否则消息服务器以为这条消息没处理掉 后续还会在发
            channel.basicAck(message.getMessageProperties().getDeliveryTag(),false);
            System.out.println("receiver success");
        } catch (IOException e) {
            e.printStackTrace();
            //丢弃这条消息
            //channel.basicNack(message.getMessageProperties().getDeliveryTag(), false,false);
            System.out.println("receiver fail");
        }   
}

channel配置概括

 channel.basicAck(message.getMessageProperties().getDeliveryTag(),false);
//消息的标识，false只确认当前一个消息收到，true确认所有consumer获得的消息

channel.basicAck(message.getMessageProperties().getDeliveryTag(), false);

//ack返回false，并重新回到队列，api里面解释得很清楚

channel.basicNack(message.getMessageProperties().getDeliveryTag(), false, true);

//拒绝消息

channel.basicReject(message.getMessageProperties().getDeliveryTag(), true);