RabbitMQ解决分布式事务

2022-01-04 01:47:15

案例说明：

经典案例，以目前流行点外卖的案例，用户下单后，调用订单服务，让后订单服务调用派单系统通知送外卖人员送单，这时候订单系统与派单系统采用MQ异步通讯，保证订单表和派单表必须一致！

用传统的HTTP协议不能解决高并发：

RabbitMQ解决分布式事务

RabbitMQ解决分布式事务原理方案

  1. 确保生产者一定要将数据投递到MQ服务器中
    • 生产者采用confirm，确认应答机制
    • 如果失败，生产者进行重试。
  2. MQ消费者消息能够正常消费消息。
    • 采用手动ACK模式，使用补偿机制，注意幂等性问题。
  3. 采用补单机制。
    • 在创建一个补单消费者进行监听，如果订单创建后，又回滚了(数据不一致)，此时需要将订单进行补偿。
    • 交换机采用路由键模式，补单队列和派但队列都绑定同一个路由键。

RabbitMQ解决分布式事务

代码

派件表：

create TABLE platoon(

  id INT PRIMARY KEY AUTO_INCREMENT,

  orderId VARCHAR(255),

  takeout_userId int

)

订单表：

create TABLE order_info(

  id INT PRIMARY KEY AUTO_INCREMENT,

  name VARCHAR(30),

  order_money INT,

  orderId VARCHAR(255)

);

生产者   

1.实现接口 implements RabbitTemplate.ConfirmCallback

2. 重写回调方法 ，成功、失败的调用

@Override
public void confirm(CorrelationData correlationData, boolean ack, String cause) {

send方法里面调用回调函数：

this.rabbitTemplate.setMandatory(true);

this.rabbitTemplate.setConfirmCallback(this);

yml需要配置回调机制：

###开启消息确认机制 confirms

publisher-confirms: true

publisher-returns: true

注意：重试也是有一定次数限制的 如果超过一定次数 就需要进行人工补偿了

下单：

RabbitMQ解决分布式事务

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>rabbitmq_order</artifactId>

    <version>0.0.1-SNAPSHOT</version>

    <parent>

    <groupId>org.springframework.boot</groupId>

    <artifactId>spring-boot-starter-parent</artifactId>

    <version>2.0.1.RELEASE</version>

</parent>

    <dependencies>

        <dependency>

            <groupId>org.mybatis.spring.boot</groupId>

            <artifactId>mybatis-spring-boot-starter</artifactId>

            <version>1.1.1</version>

        </dependency>

        <!-- mysql 依赖 -->

        <dependency>

            <groupId>mysql</groupId>

            <artifactId>mysql-connector-java</artifactId>

        </dependency>

        <!-- 阿里巴巴数据源 -->

        <dependency>

            <groupId>com.alibaba</groupId>

            <artifactId>druid</artifactId>

            <version>1.0.14</version>

        </dependency>

        <!-- SpringBoot整合Web组件 -->

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-web</artifactId>

        </dependency>

        <!-- springboot- 整个 lombok -->

        <dependency>

            <groupId>org.projectlombok</groupId>

            <artifactId>lombok</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>

基础包：

public interface ApiConstants {

    // 响应请求成功

    String HTTP_RES_CODE_200_VALUE = "success";

    // 系统错误

    String HTTP_RES_CODE_500_VALUE = "fial";

    // 响应请求成功code

    Integer HTTP_RES_CODE_200 = 200;

    // 系统错误

    Integer HTTP_RES_CODE_500 = 500;

    // 未关联QQ账号

    Integer HTTP_RES_CODE_201 = 201;

}
import org.springframework.stereotype.Component;

@Component

public class BaseApiService {

    public ResponseBase setResultError(Integer code, String msg) {

        return setResult(code, msg, null);

    }

    // 返回错误，可以传msg

    public ResponseBase setResultError(String msg) {

        return setResult(ApiConstants.HTTP_RES_CODE_500, msg, null);

    }

    // 返回成功，可以传data值

    public ResponseBase setResultSuccess(Object data) {

        return setResult(ApiConstants.HTTP_RES_CODE_200, ApiConstants.HTTP_RES_CODE_200_VALUE, data);

    }

    // 返回成功，沒有data值

    public ResponseBase setResultSuccess() {

        return setResult(ApiConstants.HTTP_RES_CODE_200, ApiConstants.HTTP_RES_CODE_200_VALUE, null);

    }

    // 返回成功，沒有data值

    public ResponseBase setResultSuccess(String msg) {

        return setResult(ApiConstants.HTTP_RES_CODE_200, msg, null);

    }

    // 通用封装

    public ResponseBase setResult(Integer code, String msg, Object data) {

        return new ResponseBase(code, msg, data);

    }

}
import lombok.Data;

@Data

public class ResponseBase {

    private Integer rtnCode;

    private String msg;

    private Object data;

    public ResponseBase() {

    }

    public ResponseBase(Integer rtnCode, String msg, Object data) {

        super();

        this.rtnCode = rtnCode;

        this.msg = msg;

        this.data = data;

    }

    @Override

    public String toString() {

        return "ResponseBase [rtnCode=" + rtnCode + ", msg=" + msg + ", data=" + data + "]";

    }

}

补偿队列：

import lombok.Data;

@Data

public class ResponseBase {

    private Integer rtnCode;

    private String msg;

    private Object data;

    public ResponseBase() {

    }

    public ResponseBase(Integer rtnCode, String msg, Object data) {

        super();

        this.rtnCode = rtnCode;

        this.msg = msg;

        this.data = data;

    }

    @Override

    public String toString() {

        return "ResponseBase [rtnCode=" + rtnCode + ", msg=" + msg + ", data=" + data + "]";

    }

}

entity：

import lombok.Data;

@Data

public class OrderEntity {

    private Long id;

    // 订单名称

    private String name;

    // 下单金额

    private Double orderMoney;

    // 订单id

    private String orderId;

}

mapper：

import org.apache.ibatis.annotations.Insert;

import org.apache.ibatis.annotations.Options;

import org.apache.ibatis.annotations.Param;

import org.apache.ibatis.annotations.Select;

import com.mayikt.entity.OrderEntity;

public interface OrderMapper {

    @Insert(value = "INSERT INTO `order_info` VALUES (#{id}, #{name}, #{orderMoney},#{orderId})")

    @Options(useGeneratedKeys = true, keyProperty = "id", keyColumn = "id")

    public int addOrder(OrderEntity orderEntity);

    @Select("SELECT id as id ,name as name , order_money as orderMoney,orderId as orderId from order_info where orderId=#{orderId};")

    public OrderEntity findOrderId(@Param("orderId") String orderId);

}

MQ的配置：

import org.springframework.amqp.core.Binding;

import org.springframework.amqp.core.BindingBuilder;

import org.springframework.amqp.core.DirectExchange;

import org.springframework.amqp.core.DirectExchange;

import org.springframework.amqp.core.FanoutExchange;

import org.springframework.amqp.core.Queue;

import org.springframework.context.annotation.Bean;

import org.springframework.stereotype.Component;

@Component

public class RabbitmqConfig {

    // 下单并且派单存队列

    public static final String ORDER_DIC_QUEUE = "order_dic_queue";

    // 补单队列，判断订单是否已经被创建

    public static final String ORDER_CREATE_QUEUE = "order_create_queue";

    // 下单并且派单交换机

    private static final String ORDER_EXCHANGE_NAME = "order_exchange_name";

    // 1.定义订单队列

    @Bean

    public Queue directOrderDicQueue() {

        return new Queue(ORDER_DIC_QUEUE);

    }

    // 2.定义补订单队列

    @Bean

    public Queue directCreateOrderQueue() {

        return new Queue(ORDER_CREATE_QUEUE);

    }

    // 2.定义交换机

    @Bean

    DirectExchange directOrderExchange() {

        return new DirectExchange(ORDER_EXCHANGE_NAME);

    }

    // 3.订单队列与交换机绑定

    @Bean

    Binding bindingExchangeOrderDicQueue() {

        return BindingBuilder.bind(directOrderDicQueue()).to(directOrderExchange()).with("orderRoutingKey");

    }

    // 3.补单队列与交换机绑定

    @Bean

    Binding bindingExchangeCreateOrder() {

        return BindingBuilder.bind(directCreateOrderQueue()).to(directOrderExchange()).with("orderRoutingKey");

    }

}

service：

import java.util.UUID;

import org.springframework.amqp.core.Message;

import org.springframework.amqp.core.MessageBuilder;

import org.springframework.amqp.core.MessageProperties;

import org.springframework.amqp.rabbit.core.RabbitTemplate;

import org.springframework.amqp.rabbit.support.CorrelationData;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Service;

import com.alibaba.fastjson.JSONObject;

import com.mayikt.base.BaseApiService;

import com.mayikt.base.ResponseBase;

import com.mayikt.entity.OrderEntity;

import com.mayikt.mapper.OrderMapper;

@Service

public class OrderService extends BaseApiService implements RabbitTemplate.ConfirmCallback {

    @Autowired

    private OrderMapper orderMapper;

    @Autowired

    private RabbitTemplate rabbitTemplate;

    public ResponseBase addOrderAndDispatch() {

        //先下单 订单表插入数据

        OrderEntity orderEntity = new OrderEntity();

        orderEntity.setName("黄焖鸡米饭");

        // 价格是300元

        orderEntity.setOrderMoney(300d);

        // 商品id

        String orderId = UUID.randomUUID().toString();

        orderEntity.setOrderId(orderId);

        // 1.先下单，创建订单 (往订单数据库中插入一条数据)

        int orderResult = orderMapper.addOrder(orderEntity);

        System.out.println("orderResult:" + orderResult);

        if (orderResult <= 0) {

            return setResultError("下单失败!");

        }

        // 2.订单表插插入完数据后 订单表发送 外卖小哥

        send(orderId);

    //    int i = 1/0;   //发生异常

        return setResultSuccess();

    }

    private void send(String orderId) {

        JSONObject jsonObect = new JSONObject();

        jsonObect.put("orderId", orderId);

        String msg = jsonObect.toJSONString();

        System.out.println("msg:" + msg);

        // 封装消息

        Message message = MessageBuilder.withBody(msg.getBytes()).setContentType(MessageProperties.CONTENT_TYPE_JSON)

                .setContentEncoding("utf-8").setMessageId(orderId).build();

        // 构建回调返回的数据

        CorrelationData correlationData = new CorrelationData(orderId);

        // 发送消息

        this.rabbitTemplate.setMandatory(true);

        this.rabbitTemplate.setConfirmCallback(this);

        rabbitTemplate.convertAndSend("order_exchange_name", "orderRoutingKey", message, correlationData);

    }

    // 生产消息确认机制 生产者往服务器端发送消息的时候 采用应答机制

    @Override

    public void confirm(CorrelationData correlationData, boolean ack, String cause) {

        String orderId = correlationData.getId(); //id 都是相同的哦  全局ID

        System.out.println("消息id:" + correlationData.getId());

        if (ack) { //消息发送成功

            System.out.println("消息发送确认成功");

        } else {

            //重试机制

            send(orderId);

            System.out.println("消息发送确认失败:" + cause);

        }

    }

}

controller：

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.bind.annotation.RestController;

import com.mayikt.base.BaseApiService;

import com.mayikt.base.ResponseBase;

import com.mayikt.service.OrderService;

@RestController

public class OrderController extends BaseApiService {

    @Autowired

    private OrderService orderService;

    @RequestMapping("/addOrder")

    public ResponseBase addOrder() {

        return orderService.addOrderAndDispatch();

    }

}

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

    ###开启消息确认机制 confirms

    publisher-confirms: true

    publisher-returns: true

  #数据库连接信息

  datasource:

        name: test

        url: jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=utf8&autoReconnect=true&rewriteBatchedStatements=TRUE

        username: root

        password: root

        # 使用druid数据源

        type: com.alibaba.druid.pool.DruidDataSource

        driver-class-name: com.mysql.jdbc.Driver

启动类：

package com.mayikt;

import org.mybatis.spring.annotation.MapperScan;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

@MapperScan("com.mayikt.mapper")

@SpringBootApplication

public class AppOrder {

    public static void main(String[] args) {

        SpringApplication.run(AppOrder.class, args);

    }

}

派单：

RabbitMQ解决分布式事务

Entity:

package com.mayikt.entity;

import lombok.Data;

@Data

public class DispatchEntity {

    private Long id;

    // 订单号

    private String orderId;

    // 外卖员id

    private Long takeoutUserId;

}

Mapper:

package com.mayikt.mapper;

import org.apache.ibatis.annotations.Insert;

import com.mayikt.entity.DispatchEntity;

public interface DispatchMapper {

    /**

     * 新增派单任务

     */

    @Insert("INSERT into platoon values (null,#{orderId},#{takeoutUserId});")

    public int insertDistribute(DispatchEntity distributeEntity);

}

consumer:

做一些路由器 队列 路由键的绑定 声明工作

package com.mayikt.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.DirectExchange;

import org.springframework.amqp.core.FanoutExchange;

import org.springframework.amqp.core.Queue;

import org.springframework.context.annotation.Bean;

import org.springframework.stereotype.Component;

@Component

public class RabbitmqConfig {

    // 下单并且派单存队列

    public static final String ORDER_DIC_QUEUE = "order_dic_queue";

    // 补单队列，判断订单是否已经被创建

    public static final String ORDER_CREATE_QUEUE = "order_create_queue";

    // 下单并且派单交换机

    private static final String ORDER_EXCHANGE_NAME = "order_exchange_name";

    // 1.定义派单队列

    @Bean

    public Queue OrderDicQueue() {

        return new Queue(ORDER_DIC_QUEUE);

    }

/*

    // 2.定义补订单队列

    @Bean

    public Queue directCreateOrderQueue() {

        return new Queue(ORDER_CREATE_QUEUE);

    }*/

    // 2.定义交换机

    @Bean

    DirectExchange directOrderExchange() {

        return new DirectExchange(ORDER_EXCHANGE_NAME);

    }

    // 3.订单队列与交换机绑定

    @Bean

    Binding bindingExchangeOrderDicQueue() {

        return BindingBuilder.bind(OrderDicQueue()).to(directOrderExchange()).with("orderRoutingKey");

    }

    /*// 3.补单队列与交换机绑定

    @Bean

    Binding bindingExchangeCreateOrder() {

        return BindingBuilder.bind(OrderDicQueue()).to(directOrderExchange()).with("orderRoutingKey");

    }*/

}

派件消费：

package com.mayikt.rabbitmq.consumer;

import java.util.Map;

import org.apache.commons.lang3.StringUtils;

import org.springframework.amqp.core.Message;

import org.springframework.amqp.rabbit.annotation.RabbitListener;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.messaging.handler.annotation.Headers;

import org.springframework.stereotype.Component;

import com.alibaba.fastjson.JSONObject;

import com.mayikt.entity.DispatchEntity;

import com.mayikt.mapper.DispatchMapper;

import com.rabbitmq.client.Channel;

/**

 * 派单服务

 */

@Component

public class DispatchConsumer {

    @Autowired

    private DispatchMapper dispatchMapper;

    @RabbitListener(queues = "order_dic_queue")

    public void process(Message message, @Headers Map<String, Object> headers, Channel channel) throws Exception {

        String messageId = message.getMessageProperties().getMessageId();

        String msg = new String(message.getBody(), "UTF-8");

        System.out.println("派单服务平台" + msg + ",消息id:" + messageId);

        JSONObject jsonObject = JSONObject.parseObject(msg);

        String orderId = jsonObject.getString("orderId");

        if (StringUtils.isEmpty(orderId)) {

            // 日志记录

            return;

        }

        DispatchEntity dispatchEntity = new DispatchEntity();

        // 订单id

        dispatchEntity.setOrderId(orderId);

        // 外卖员id

        dispatchEntity.setTakeoutUserId(12l);

        try {

            int insertDistribute = dispatchMapper.insertDistribute(dispatchEntity);

            if (insertDistribute > 0) {

                // 手动签收消息,通知mq服务器端删除该消息

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

            }

        } catch (Exception e) {

            e.printStackTrace();

            // // 丢弃该消息

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

        }

    }

}

启动类：

package com.mayikt;

import org.mybatis.spring.annotation.MapperScan;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

@MapperScan("com.mayikt.mapper")

@SpringBootApplication

public class AppDispatch {

    public static void main(String[] args) {

        SpringApplication.run(AppDispatch.class, args);

    }

}

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（程序出现异常的情况下会）进行重试

          enabled: true

         ####最大重试次数

          max-attempts: 5

        ####重试间隔次数

          initial-interval: 3000

        ####开启手动ack

        acknowledge-mode: manual

  #数据库连接信息

  datasource:

        name: test

        url: jdbc:mysql://127.0.0.1:3306/test?useUnicode=true&characterEncoding=utf8&autoReconnect=true&rewriteBatchedStatements=TRUE

        username: root

        password: root

        # 使用druid数据源

        type: com.alibaba.druid.pool.DruidDataSource

        driver-class-name: com.mysql.jdbc.Driver

server:

  port: 8081

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_stock</artifactId>

    <version>0.0.1-SNAPSHOT</version>

    <parent>

        <groupId>org.springframework.boot</groupId>

        <artifactId>spring-boot-starter-parent</artifactId>

        <version>2.0.1.RELEASE</version>

    </parent>

    <dependencies>

        <dependency>

            <groupId>org.mybatis.spring.boot</groupId>

            <artifactId>mybatis-spring-boot-starter</artifactId>

            <version>1.1.1</version>

        </dependency>

        <!-- mysql 依赖 -->

        <dependency>

            <groupId>mysql</groupId>

            <artifactId>mysql-connector-java</artifactId>

        </dependency>

        <!-- 阿里巴巴数据源 -->

        <dependency>

            <groupId>com.alibaba</groupId>

            <artifactId>druid</artifactId>

            <version>1.0.14</version>

        </dependency>

        <!-- SpringBoot整合Web组件 -->

        <dependency>

            <groupId>org.springframework.boot</groupId>

            <artifactId>spring-boot-starter-web</artifactId>

        </dependency>

        <!-- springboot- 整个 lombok -->

        <dependency>

            <groupId>org.projectlombok</groupId>

            <artifactId>lombok</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>
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