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RabbitMQ整合Spring Booot【消费者补偿幂等问题】

如果消费者运行时候报错了

package com.toov5.msg.SMS;

import org.springframework.amqp.rabbit.annotation.RabbitHandler;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.stereotype.Component;

@Component 
@RabbitListener(queues="fanout_sms_queue")   
public class SMSConsumer {
    
    @RabbitHandler  
   public void process(String mString) {
       System.out.println("短信消费者获取生产者消息msg"+mString);
       int i = 1/0;
   }
}

当生产者投递消息后：

消费者会不停的进行打印:

消息一直没有被消费

原因 Rabbitmq 默认情况下如果消费者程序出现异常情况会自动实现补偿机制也就是重试机制

@RabbitListener底层使用AOP进行拦截，如果程序没有抛出异常，自动提交事务。如果Aop使用异常通知拦截获取异常信息的话，自动实现补偿机制，该消息会一直缓存在Rabbitmq服务器端进行重放，一直重试到不抛出异常为准。

可以修改重试策略

一般来说默认5s重试一次，

消费者配置：

 listener:
      simple:
        retry:
        ####开启消费者重试
          enabled: true
         ####最大重试次数（默认无数次）
          max-attempts: 5
        ####重试间隔次数
          initial-interval: 3000

效果：充实5次不行就放弃了

MQ重试机制机制需要注意的问题

如何合适选择重试机制

情况1: 消费者获取到消息后，调用第三方接口，但接口暂时无法访问，是否需要重试?

需要重试别人的问题不是我自己的问题

情况2: 消费者获取到消息后，抛出数据转换异常，是否需要重试?

不需要重试充实一亿次也是如此木有必要需要发布版本解决

总结：

对于情况2，如果消费者代码抛出异常是需要发布新版本才能解决的问题，那么不需要重试，重试也无济于事。应该采用日志记录+定时任务job健康检查+人工进行补偿
把错误记录在日志里面，通过定时Job去自动的补偿，或通过人工去补偿。

传统的HTTP请求如果失败了没法自动重试，当然自己可以写个循环实现。MQ完全自己自带的。

情况2的拓展延申：

将之前的案例改为邮件消费者调用邮件第三方接口

伪代码：

在consumer 中调用接口后判断返回值由于RabbitMQ 在消费者异常时候会进行重试机制进行补偿

所以可以抛出个异常来实现

Consumer：

String result = template.Email();

if(result == null){

throw new Exception("调用第三方邮件服务器接口失败!");

}

producer：

pom:

<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.itmayiedu</groupId>
    <artifactId>rabbitmq_producer_springboot</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.0.RELEASE</version>
    </parent>
    <dependencies>

        <!-- springboot-web组件 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- 添加springboot对amqp的支持 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
        </dependency>
        <!--fastjson -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.49</version>
        </dependency>
    </dependencies>
</project>

config:

package com.itmayiedu.rabbitmq.config;

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.context.annotation.Bean;
import org.springframework.stereotype.Component;

//Fanout 类型 发布订阅模式
@Component
public class FanoutConfig {

    // 邮件队列
    private String FANOUT_EMAIL_QUEUE = "fanout_email_queue";

    // 短信队列
    private String FANOUT_SMS_QUEUE = "fanout_sms_queue";
    // fanout 交换机
    private String EXCHANGE_NAME = "fanoutExchange";

    // 1.定义邮件队列
    @Bean
    public Queue fanOutEamilQueue() {
        return new Queue(FANOUT_EMAIL_QUEUE);
    }

    // 2.定义短信队列
    @Bean
    public Queue fanOutSmsQueue() {
        return new Queue(FANOUT_SMS_QUEUE);
    }

    // 2.定义交换机
    @Bean
    FanoutExchange fanoutExchange() {
        return new FanoutExchange(EXCHANGE_NAME);
    }

    // 3.队列与交换机绑定邮件队列
    @Bean
    Binding bindingExchangeEamil(Queue fanOutEamilQueue, FanoutExchange fanoutExchange) {
        return BindingBuilder.bind(fanOutEamilQueue).to(fanoutExchange);
    }

    // 4.队列与交换机绑定短信队列
    @Bean
    Binding bindingExchangeSms(Queue fanOutSmsQueue, FanoutExchange fanoutExchange) {
        return BindingBuilder.bind(fanOutSmsQueue).to(fanoutExchange);
    }
}

Producer:

package com.itmayiedu.rabbitmq;

import java.util.UUID;

import org.springframework.amqp.core.AmqpTemplate;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.core.MessageBuilder;
import org.springframework.amqp.core.MessageProperties;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import com.alibaba.fastjson.JSONObject;

@Component
public class FanoutProducer {
    @Autowired
    private AmqpTemplate amqpTemplate;

    public void send(String queueName) {
        JSONObject jsonObject = new JSONObject();
        jsonObject.put("email", "xx@163.com");
        jsonObject.put("timestamp", System.currentTimeMillis());
        String jsonString = jsonObject.toJSONString();
        System.out.println("jsonString:" + jsonString);
        // 设置消息唯一id 保证每次重试消息id唯一
        /*Message message = MessageBuilder.withBody(jsonString.getBytes())
                .setContentType(MessageProperties.CONTENT_TYPE_JSON).setContentEncoding("utf-8")
                .setMessageId(UUID.randomUUID() + "").build();*/
        amqpTemplate.convertAndSend(queueName, jsonString);
    }
}

Controller:

package com.itmayiedu.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.itmayiedu.rabbitmq.FanoutProducer;

@RestController
public class ProducerController {
    @Autowired
    private FanoutProducer fanoutProducer;

    @RequestMapping("/sendFanout")
    public String sendFanout(String queueName) {
        fanoutProducer.send(queueName);
        return "success";
    }
}

yml:

spring:
  rabbitmq:
  ####连接地址
    host: 192.168.91.6
   ####端口号   
    port: 5672
   ####账号 
    username: admin
   ####密码  
    password: admin
   ### 地址
    virtual-host: /admin_toov5

启动类：

package com.itmayiedu;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class AppProducer {

    public static void main(String[] args) {
        SpringApplication.run(AppProducer.class, args);
    }

}

Consumer：

pom:

<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.itmayiedu</groupId>
    <artifactId>rabbitmq_consumer_springboot</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.0.RELEASE</version>
    </parent>
    <dependencies>

        <!-- springboot-web组件 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- 添加springboot对amqp的支持 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>

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

        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
        </dependency>
        <!--fastjson -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.49</version>
        </dependency>

    </dependencies>
</project>

utils:

package com.itmayiedu.rabbitmq.utils;

import com.alibaba.fastjson.JSONObject;
import org.apache.http.HttpEntity;
import org.apache.http.HttpStatus;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;

/**
 * HttpClient4.3工具类
 * 
 * @author hang.luo
 */
public class HttpClientUtils {
    private static Logger logger = LoggerFactory.getLogger(HttpClientUtils.class); // 日志记录

    private static RequestConfig requestConfig = null;

    static {
        // 设置请求和传输超时时间
        requestConfig = RequestConfig.custom().setSocketTimeout(2000).setConnectTimeout(2000).build();
    }

    /**
     * post请求传输json参数
     * 
     * @param url
     *            url地址
     * @param json
     *            参数
     * @return
     */
    public static JSONObject httpPost(String url, JSONObject jsonParam) {
        // post请求返回结果
        CloseableHttpClient httpClient = HttpClients.createDefault();
        JSONObject jsonResult = null;
        HttpPost httpPost = new HttpPost(url);
        // 设置请求和传输超时时间
        httpPost.setConfig(requestConfig);
        try {
            if (null != jsonParam) {
                // 解决中文乱码问题
                StringEntity entity = new StringEntity(jsonParam.toString(), "utf-8");
                entity.setContentEncoding("UTF-8");
                entity.setContentType("application/json");
                httpPost.setEntity(entity);
            }
            CloseableHttpResponse result = httpClient.execute(httpPost);
            // 请求发送成功，并得到响应
            if (result.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                String str = "";
                try {
                    // 读取服务器返回过来的json字符串数据
                    str = EntityUtils.toString(result.getEntity(), "utf-8");
                    // 把json字符串转换成json对象
                    jsonResult = JSONObject.parseObject(str);
                } catch (Exception e) {
                    logger.error("post请求提交失败:" + url, e);
                }
            }
        } catch (IOException e) {
            logger.error("post请求提交失败:" + url, e);
        } finally {
            httpPost.releaseConnection();
        }
        return jsonResult;
    }

    /**
     * post请求传输String参数 例如：name=Jack&sex=1&type=2
     * Content-type:application/x-www-form-urlencoded
     * 
     * @param url
     *            url地址
     * @param strParam
     *            参数
     * @return
     */
    public static JSONObject httpPost(String url, String strParam) {
        // post请求返回结果
        CloseableHttpClient httpClient = HttpClients.createDefault();
        JSONObject jsonResult = null;
        HttpPost httpPost = new HttpPost(url);
        httpPost.setConfig(requestConfig);
        try {
            if (null != strParam) {
                // 解决中文乱码问题
                StringEntity entity = new StringEntity(strParam, "utf-8");
                entity.setContentEncoding("UTF-8");
                entity.setContentType("application/x-www-form-urlencoded");
                httpPost.setEntity(entity);
            }
            CloseableHttpResponse result = httpClient.execute(httpPost);
            // 请求发送成功，并得到响应
            if (result.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                String str = "";
                try {
                    // 读取服务器返回过来的json字符串数据
                    str = EntityUtils.toString(result.getEntity(), "utf-8");
                    // 把json字符串转换成json对象
                    jsonResult = JSONObject.parseObject(str);
                } catch (Exception e) {
                    logger.error("post请求提交失败:" + url, e);
                }
            }
        } catch (IOException e) {
            logger.error("post请求提交失败:" + url, e);
        } finally {
            httpPost.releaseConnection();
        }
        return jsonResult;
    }

    /**
     * 发送get请求
     * 
     * @param url
     *            路径
     * @return
     */
    public static JSONObject httpGet(String url) {
        // get请求返回结果
        JSONObject jsonResult = null;
        CloseableHttpClient client = HttpClients.createDefault();
        // 发送get请求
        HttpGet request = new HttpGet(url);
        request.setConfig(requestConfig);
        try {
            CloseableHttpResponse response = client.execute(request);

            // 请求发送成功，并得到响应
            if (response.getStatusLine().getStatusCode() == HttpStatus.SC_OK) {
                // 读取服务器返回过来的json字符串数据
                HttpEntity entity = response.getEntity();
                String strResult = EntityUtils.toString(entity, "utf-8");
                // 把json字符串转换成json对象
                jsonResult = JSONObject.parseObject(strResult);
            } else {
                logger.error("get请求提交失败:" + url);
            }
        } catch (IOException e) {
            logger.error("get请求提交失败:" + url, e);
        } finally {
            request.releaseConnection();
        }
        return jsonResult;
    }

}

consumer:

package com.itmayiedu.rabbitmq;

import java.util.Map;

import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.amqp.support.AmqpHeaders;
import org.springframework.messaging.handler.annotation.Headers;
import org.springframework.stereotype.Component;

import com.alibaba.fastjson.JSONObject;
import com.itmayiedu.rabbitmq.utils.HttpClientUtils;
import com.rabbitmq.client.Channel;

//邮件队列
@Component
public class FanoutEamilConsumer {
     @RabbitListener(queues = "fanout_email_queue")
     public void process(String msg) throws Exception {
     System.out.println("邮件消费者获取生产者消息msg:" + msg);
     JSONObject jsonObject = JSONObject.parseObject(msg);
     // 获取email参数
     String email = jsonObject.getString("email");
     // 请求地址
     String emailUrl = "http://127.0.0.1:8083/sendEmail?email=" + email;
     JSONObject result = HttpClientUtils.httpGet(emailUrl);
     if (result == null) {
     // 因为网络原因,造成无法访问,继续重试
     throw new Exception("调用接口失败!");
     }
     System.out.println("执行结束....");
    
     }
}

yml:

spring:
  rabbitmq:
  ####连接地址
    host: 192.168.91.6
   ####端口号   
    port: 5672
   ####账号 
    username: admin
   ####密码  
    password: admin
   ### 地址
    virtual-host: /admin_toov5
    listener: 
      simple:
        retry:
        ####开启消费者异常重试
          enabled: true
         ####最大重试次数
          max-attempts: 5
        ####重试间隔次数
          initial-interval: 2000
       

server:
  port: 8081

启动类：

package com.itmayiedu.rabbitmq;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class AppConsumer {

    public static void main(String[] args) {
        SpringApplication.run(AppConsumer.class, args);
    }

}

邮件服务器：

package com.mayikt.controller;

import java.util.HashMap;
import java.util.Map;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

@SpringBootApplication
@RestController
public class MsgController {

    // 模拟第三方发送邮件
    @RequestMapping("/sendEmail")
    public Map<String, Object> sendEmail(String email) {
        System.out.println("开始发送邮件:" + email);
        Map<String, Object> result = new HashMap<String, Object>();
        result.put("code", "200");
        result.put("msg", "发送邮件成功..");
        System.out.println("发送邮件成功");
        return result;
    }

    public static void main(String[] args) {
        SpringApplication.run(MsgController.class, args);
    }

}

yml:

server:
  port: 8083

pom:

<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.mayikt</groupId>
    <artifactId>mayikt_sms</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.0.RELEASE</version>
    </parent>
    <dependencies>

        <!-- springboot-web组件 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- 添加springboot对amqp的支持 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>

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

        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
        </dependency>
        <!--fastjson -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.49</version>
        </dependency>

    </dependencies>
</project>

在没有启动邮件服务器时候，消费者调用接口失败会一直重试，重试五次。

在此期间，如果启动成功，则重试成功，不再重试，不再进行补偿机制。

消费者如果保证消息幂等性，不被重复消费

背景：

网络延迟传输中，或者消费出现异常或者是消费延迟，会造成进行MQ重试进行重试补偿机制，在重试过程中，可能会造成重复消费。

解决办法:

使用全局MessageID判断消费方使用同一个，解决幂等性。

只要重试过程中，判断如果已经走完了不能再继续走继续执行了

MQ消费者的幂等行的解决一般使用全局ID 或者写个唯一标识比如时间戳或者UUID 或者订单号

改进：

producer：

添加：

// 设置消息唯一id 保证每次重试消息id唯一  
        Message message = MessageBuilder.withBody(jsonString.getBytes())
                .setContentType(MessageProperties.CONTENT_TYPE_JSON).setContentEncoding("utf-8")
                .setMessageId(UUID.randomUUID() + "").build(); //消息id设置在请求头里面 用UUID做全局ID 
        amqpTemplate.convertAndSend(queueName, message);

全部代码：

package com.itmayiedu.rabbitmq;

import java.util.UUID;

import org.springframework.amqp.core.AmqpTemplate;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.core.MessageBuilder;
import org.springframework.amqp.core.MessageProperties;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import com.alibaba.fastjson.JSONObject;

@Component
public class FanoutProducer {
    @Autowired
    private AmqpTemplate amqpTemplate;

    public void send(String queueName) {
        JSONObject jsonObject = new JSONObject();
        jsonObject.put("email", "xx@163.com");
        jsonObject.put("timestamp", System.currentTimeMillis());
        String jsonString = jsonObject.toJSONString();
        System.out.println("jsonString:" + jsonString);
        // 设置消息唯一id 保证每次重试消息id唯一  
        Message message = MessageBuilder.withBody(jsonString.getBytes())
                .setContentType(MessageProperties.CONTENT_TYPE_JSON).setContentEncoding("utf-8")
                .setMessageId(UUID.randomUUID() + "").build(); //消息id设置在请求头里面 用UUID做全局ID 
        amqpTemplate.convertAndSend(queueName, message);
    }
}

同样的消费者也需要修改：

方法参数类型为 Message 然后可以获取这个ID 然后可以进行业务逻辑操作

 @RabbitListener(queues = "fanout_email_queue")
     public void process(Message message) throws Exception {
     // 获取消息Id
     String messageId = message.getMessageProperties().getMessageId();  //id获取之
     String msg = new String(message.getBody(), "UTF-8"); //消息内容获取之
     System.out.println("-----邮件消费者获取生产者消息-----------------" + "messageId:" + messageId + ",消息内容:" +
     msg);
     if (messageId == null) {
            return;
        }
     JSONObject jsonObject = JSONObject.parseObject(msg);
     // 获取email参数
     String email = jsonObject.getString("email");
     // 请求地址
     String emailUrl = "http://127.0.0.1:8083/sendEmail?email=" + email;
     JSONObject result = HttpClientUtils.httpGet(emailUrl);
     if (result == null) {
     // 因为网络原因,造成无法访问,继续重试
     throw new Exception("调用接口失败!");
     }
     System.out.println("执行结束....");
     //messId 的情况写入到redis 中  成功就修改为空
     }

重试机制都是间隔性的每次都是一个线程单线程重试

关于应答模式：

Spring boot 中进行 AOP拦截自动帮助做重试

手动应答的话，如果不告诉服务器已经消费成功，则服务器不会删除消息。告诉消费成功了才会删除。

消费者的yml加入：

 acknowledge-mode: manual

spring:
  rabbitmq:
  ####连接地址
    host: 192.168.91.6
   ####端口号   
    port: 5672
   ####账号 
    username: admin
   ####密码  
    password: admin
   ### 地址
    virtual-host: /admin_toov5
    listener: 
      simple:
        retry:
        ####开启消费者异常重试
          enabled: true
         ####最大重试次数
          max-attempts: 5
        ####重试间隔次数
          initial-interval: 2000
        ####开启手动ack  
        acknowledge-mode: manual 

server:
  port: 8081

开启模式之后：

消费者参数需要加入： @Headers Map<String, Object> headers, Channel channel

代码逻辑最后面加入：

// // 手动ack
Long deliveryTag = (Long) headers.get(AmqpHeaders.DELIVERY_TAG);
// 手动签收  告诉RabbitMQ 消费成功了  消息可以删除了
channel.basicAck(deliveryTag, false);

代码如下：

@RabbitListener(queues = "fanout_email_queue")
    public void process(Message message, @Headers Map<String, Object> headers, Channel channel) throws Exception {
        // 获取消息Id
        String messageId = message.getMessageProperties().getMessageId();
        String msg = new String(message.getBody(), "UTF-8");
        System.out.println("邮件消费者获取生产者消息" + "messageId:" + messageId + ",消息内容:" + msg);
        JSONObject jsonObject = JSONObject.parseObject(msg);
        // 获取email参数
        String email = jsonObject.getString("email");
        // 请求地址
        String emailUrl = "http://127.0.0.1:8083/sendEmail?email=" + email;
        JSONObject result = HttpClientUtils.httpGet(emailUrl);
        if (result == null) {
            // 因为网络原因,造成无法访问,继续重试
            throw new Exception("调用接口失败!");
        }
        // // 手动ack
        Long deliveryTag = (Long) headers.get(AmqpHeaders.DELIVERY_TAG);
        // 手动签收
        channel.basicAck(deliveryTag, false);
        System.out.println("执行结束....");
    }

查看全文

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原文地址：https://www.cnblogs.com/toov5/p/10287183.html