springcloud——stream（消息驱动）解决消息的重复消费和持久化问题

注：消息的重复消费和持久化问题都是通过对消息消费者（consumer）的分组实现的。同一个组之间的消息消费者存在消息的竞争关系，通过轮询的方式来实现消息的消费，同一个组之内的消息消费者（consumer）不能同时接收到相同的消息，只有其中一个能接收到这一消息。
消息的持久化：如果给消息消费者配置相应的分组，那么即使当消息消费者宕机时，消息提供者发送消息，在消息消费者启动应用成功之后也能接收到消息提供者发来的消息。

一、消息提供者

1、pom文件

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>springcloud</artifactId>
        <groupId>com.springcloud</groupId>
        <version>1.0.0</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>stream-rabbitmq-provider8801</artifactId>

    <dependencies>

        <dependency>
            <groupId>org.springframework.amqp</groupId>
            <artifactId>spring-amqp</artifactId>
            <version>2.2.9.RELEASE</version>
        </dependency>

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

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

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-netflix-eureka-client</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-stream-rabbit</artifactId>
        </dependency>

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

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>

    </dependencies>


</project>

2、主配置文件

server:
  port: 8801

spring:
  application:
    name: cloud-stream-provider

  cloud:
    stream:
      binders:    #此处设置要绑定的rabbitmq的服务信息
        defaultRabbit:    #表示定义名称，用于binding整合
          type: rabbit    #消息组件类型
          environment:    #设置rabbitmq的相关环境配置
            spring:
              rabbitmq:
                host: localhost
                port: 5672
                username: guest
                password: guest

      bindings:     #服务的整合处理
        output:     #这个名字是一个通道的名称
          destination: studyExchange      #表示要使用的Exchange名称定义
          content-type: application/json      #设置消息类型，本次为json，文本则设置"text/plain"
          binder: defaultRabbit     #设置要绑定的消息服务的具体设置


eureka:
  client:     #客户端进行eureka注册的配置
    service-url:
      defaultZone: http://eureka7001.com:7001/eureka/

  instance:
    lease-renewal-interval-in-seconds: 2      #设置心跳的时间间隔（默认是30秒）
    lease-expiration-duration-in-seconds: 5     #如果现在超过了5秒的间隔（默认是90秒）
    instance-id: send-8801.com      #在信息列表时显示主机名称
    prefer-ip-address: true     #访问的路径变为IP地址

3、主启动类

package com.springcloud;

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

/**
 * @author dc
 * @date 2020/8/8 - 16:26
 */

@SpringBootApplication
public class StreamMQMain8801 {

    public static void main(String[] args) {
        SpringApplication.run(StreamMQMain8801.class, args);
    }

}

4、service接口

package com.springcloud.service;

/**
 * @author dc
 * @date 2020/8/8 - 16:28
 */
public interface IMessageProvider {

    String send();

}

5、service实现类

package com.springcloud.service;

import org.springframework.cloud.stream.annotation.EnableBinding;
import org.springframework.cloud.stream.messaging.Source;
import org.springframework.messaging.MessageChannel;
import org.springframework.messaging.support.MessageBuilder;

import javax.annotation.Resource;
import java.util.UUID;

/**
 * @author dc
 * @date 2020/8/8 - 16:29
 */
@EnableBinding(Source.class)    //定义消息的推送管道
public class MessageProviderImpl implements IMessageProvider{

    @Resource
    private MessageChannel output;      //消息发送管道

    @Override
    public String send() {
        String serial = UUID.randomUUID().toString();
        output.send(MessageBuilder.withPayload(serial).build());
        System.out.println("******serial = " + serial);
        return null;
    }
}

6、控制器

package com.springcloud.controller;

import com.springcloud.service.IMessageProvider;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;

/**
 * @author dc
 * @date 2020/8/8 - 16:38
 */
@RestController
public class SendMessageController {

    @Resource
    private IMessageProvider messageProvider;

    @GetMapping("/sendMessage")
    public String sendMessage() {
        return messageProvider.send();
    }

}

二、消息消费者1

1、pom文件

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>springcloud</artifactId>
        <groupId>com.springcloud</groupId>
        <version>1.0.0</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>stream-rabbitmq-consumer8802</artifactId>

    <dependencies>

        <dependency>
            <groupId>org.springframework.amqp</groupId>
            <artifactId>spring-amqp</artifactId>
            <version>2.2.9.RELEASE</version>
        </dependency>

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

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

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-netflix-eureka-client</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-stream-rabbit</artifactId>
        </dependency>

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

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>

    </dependencies>

</project>

2、主配置文件

server:
  port: 8802

spring:
  application:
    name: cloud-stream-consumer

  cloud:
    stream:
      binders:
        defaultRabbit:
          type: rabbit
          environment:
            spring:
              rabbitmq:
                host: localhost
                port: 5672
                username: guest
                password: guest

      bindings:
        input:
          destination: studyExchange
          content-type: application/json
          binder: defaultRabbit
          group: dc1    #分组可以解决消息重复消费和持久化的问题

eureka:
  client:
    service-url:
      defaultZone: http://eureka7001.com:7001/eureka/

  instance:
    lease-renewal-interval-in-seconds: 2
    lease-expiration-duration-in-seconds: 5
    instance-id: receive-8802.com
    prefer-ip-address: true

3、主启动类

package com.springcloud;

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

/**
 * @author dc
 * @date 2020/8/10 - 8:48
 */
@SpringBootApplication
public class StreamMQMain8802 {

    public static void main(String[] args) {
        SpringApplication.run(StreamMQMain8802.class, args);
    }

}

4、控制器

package com.springcloud.controller;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.stream.annotation.EnableBinding;
import org.springframework.cloud.stream.annotation.StreamListener;
import org.springframework.cloud.stream.messaging.Sink;
import org.springframework.messaging.Message;
import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.RestController;

/**
 * @author dc
 * @date 2020/8/10 - 8:50
 */
@Component
@EnableBinding(Sink.class)
public class ReceiveMessageListenerController {

    @Value("${server.port}")
    private String serverPort;

    @StreamListener(Sink.INPUT)
    public void input(Message<String> message) {
        System.out.println("消费者1号，---------->接收到的消息：" + message.getPayload() + "\t port:" + serverPort);
    }

}

三、消息消费者2

与消息消费者1（除了端口号）完全相同