利用RabbitMQ实现分布式事务

　　实现要点：1、构建本地消息表及定时任务，确保消息可靠发送；2、RabbitMQ可靠消费；3、redis保证幂等

　　两个服务：订单服务和消息服务

　　订单服务相关代码，关键代码都有注释

spring:
  datasource:
    druid:
      url: jdbc:postgresql://127.0.0.1:5432/test01?characterEncoding=utf-8
      username: admin
      password: 123456
      driver-class-name: org.postgresql.Driver
      initial-size: 1
      max-active: 20
      max-wait: 6000
      pool-prepared-statements: true
      max-pool-prepared-statement-per-connection-size: 20
      connection-properties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=2000
      min-idle: 1
      time-between-eviction-runs-millis: 60000
      min-evictable-idle-time-millis: 300000
      validation-query: select 1
      test-while-idle: true
      test-on-borrow: false
      test-on-return: false
  rabbitmq:
    username: guest
    password: guest
    host: 127.0.0.1
    virtual-host: /
    port: 5672
    publisher-confirms: true
server:
  port: 8087
logging:
  level:
    org.springframework.jdbc.core.JdbcTemplate: DEBUG

　　　　 <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.10</version>
        </dependency>
        <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.8</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.47</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

package com.jlwj.mqtransaction.bean;

import lombok.Data;

import java.io.Serializable;

/**
 * @author hehang on 2019-06-27
 * @descriptionsdf
 */

@Data
public class OrderBean implements Serializable {

    private String orderNo;
    private String orderInfo;
}

package com.jlwj.mqtransaction.service;

import com.alibaba.fastjson.JSON;
import com.jlwj.mqtransaction.bean.OrderBean;
import lombok.extern.slf4j.Slf4j;
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.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Service;

import javax.annotation.PostConstruct;

/**
 * @author hehang on 2019-07-01
 * @description发动消息到MQ
 */
@Service
@Slf4j
public class RabbitMQService {

    @Autowired
    private RabbitTemplate rabbitTemplate;

    @Autowired
    private JdbcTemplate jdbcTemplate;

    @PostConstruct
    private void initRabbitTemplate(){
        //设置消息发送确认回调，发送成功后更新消息表状态
        rabbitTemplate.setConfirmCallback((CorrelationData correlationData, boolean ack, String cause) -> {
            log.info(String.valueOf(ack));
            if(ack){
                String sql = "update t_confirm set send_status = ? where id = ?";
                jdbcTemplate.update(sql,1,correlationData.getId());
            }
        });
    }
    public void sendMessage(OrderBean orderBean){
        rabbitTemplate.convertAndSend("orderExchange","orderRoutingKey", JSON.toJSONString(orderBean),
                message -> { message.getMessageProperties().setDeliveryMode(MessageDeliveryMode.PERSISTENT);return message;},
                new CorrelationData(orderBean.getOrderNo()));
    }

}

package com.jlwj.mqtransaction.service;

import com.alibaba.fastjson.JSON;
import com.jlwj.mqtransaction.bean.OrderBean;
import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.core.MessageDeliveryMode;
import org.springframework.amqp.rabbit.connection.CorrelationData;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.amqp.support.converter.Jackson2JsonMessageConverter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.PostConstruct;

/**
 * @author hehang on 2019-06-27
 * @description订单服务，简单期间不再写接口
 */

@Service
@Slf4j
public class OrderService {

    @Autowired
    private JdbcTemplate jdbcTemplate;

    @Autowired
    private RabbitMQService rabbitMQService;

    //注意加事务注解
    @Transactional(propagation = Propagation.REQUIRED)
    public void save(OrderBean orderBean){
        String sql1 = "insert into t_order(order_no,order_info) values (?,?)";
        String sql2 = "insert into t_confirm(id,message_info,send_status) values (?,?,?)";
        jdbcTemplate.update(sql1,orderBean.getOrderNo(),orderBean.getOrderInfo());
        jdbcTemplate.update(sql2,orderBean.getOrderNo(), JSON.toJSONString(orderBean),0);
        rabbitMQService.sendMessage(orderBean);
    }


}

package com.jlwj.mqtransaction.service;

import com.jlwj.mqtransaction.bean.OrderBean;
import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Service;

import java.util.List;

/**
 * @author hehang on 2019-07-01
 * @description 定时扫描confirm表，重复发送未发送的消息
 */
@Service
@Slf4j
public class OrderScheduleService {

    @Autowired
    private JdbcTemplate jdbcTemplate;

    @Autowired
    private RabbitMQService rabbitMQService;

    //定时扫描记录表，将发送状态为0的消息再次发送，甚至可以记录重发次数，必要时人工干预，生产环境中需要单独部署定时任务
    @Scheduled(cron ="30/30 * * * * ?" )
    public void scanOrder(){
        log.info("定时扫面confirm表");
        String sql = "select o.* from t_order o join t_confirm c on o.order_no = c.id where c.send_status = 0";
        List<OrderBean> orderBeanList = jdbcTemplate.queryForList(sql, OrderBean.class);
        for (OrderBean orderBean : orderBeanList) {
            rabbitMQService.sendMessage(orderBean);
        }
    }
}

　　消息服务相关代码

spring:
  rabbitmq:
    username: guest
    password: guest
    host: 127.0.0.1
    virtual-host: /
    port: 5672
    listener:
      simple:
        acknowledge-mode: manual
  redis:
    host: 127.0.0.1
      port: 6379
      timeout: 5000
      jedis:
        pool:
          max-idle: 8
          min-idle: 0
          max-active: 8
          max-wait: 1

<dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.8</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.47</version>
        </dependency>

package com.jlwj.messageservice.config;

import org.springframework.amqp.core.*;
import org.springframework.amqp.support.converter.Jackson2JsonMessageConverter;
import org.springframework.amqp.support.converter.MessageConverter;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;

/**
 * @author hehang on 2019-06-27
 * @descriptionmq配置类
 */
@Configuration
public class RabbitConfig {

    /**
     * 死信队列
     * @return
     */
    @Bean
    public Queue dlQueue(){
        return QueueBuilder.durable("dlQueue")
                .build();
    }

    @Bean
    public DirectExchange dlExchange(){
        return (DirectExchange) ExchangeBuilder.directExchange("dlExchange").build();
    }
    @Bean
    public Binding dlMessageBinding(){
        return BindingBuilder.bind(dlQueue()).to(dlExchange()).with("dlRoutingKey");
    }

    
    @Bean
    public DirectExchange messageDirectExchange() {
        return (DirectExchange) ExchangeBuilder.directExchange("orderExchange")
                .durable(true)
                .build();
    }

    @Bean
    public Queue messageQueue() {
        return QueueBuilder.durable("orderQueue")
                //配置死信
                .withArgument("x-dead-letter-exchange","dlExchange")
                .withArgument("x-dead-letter-routing-key","dlRoutingKey")
                .build();
    }

    @Bean
    public Binding messageBinding() {
        return BindingBuilder.bind(messageQueue())
                .to(messageDirectExchange())
                .with("orderRoutingKey");
    }

}

package com.jlwj.messageservice.listener;

import com.alibaba.fastjson.JSON;
import com.jlwj.messageservice.bean.OrderBean;
import com.rabbitmq.client.Channel;
import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.annotation.RabbitHandler;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.amqp.support.AmqpHeaders;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.messaging.handler.annotation.Header;
import org.springframework.messaging.handler.annotation.Payload;
import org.springframework.stereotype.Component;

import java.io.IOException;

/**
 * @author hehang on 2019-06-28
 * @description订单监听
 */
@Component
@Slf4j

public class OrderListener {

    @Autowired
    private StringRedisTemplate stringRedisTemplate;


    @RabbitListener(queues = "orderQueue")
    public void HandlerMessage(Channel channel, @Payload String message, @Header(AmqpHeaders.DELIVERY_TAG) long tag,
                                @Header(AmqpHeaders.REDELIVERED) boolean reDelivered ) throws IOException {
        log.info(message);
        OrderBean orderBean = JSON.parseObject(message,OrderBean.class);
        try {
            log.info("收到的消息为{}",JSON.toJSONString(orderBean));
            //保证幂等性
            if(stringRedisTemplate.opsForValue().get(orderBean.getOrderNo())==null){
                sendMessage(orderBean);
                stringRedisTemplate.opsForValue().set(orderBean.getOrderNo(),"1");
            }
            channel.basicAck(tag,false);
        } catch (Exception e) {
            if(reDelivered){
                log.info("消息已重复处理失败：{}",message);
                channel.basicReject(tag,false);
            }else{
                log.error("消息处理失败",e);
                //重新入队一次
                channel.basicNack(tag,false,true);
            }

        }
    }


    private void sendMessage(OrderBean orderBean)throws Exception{
        if(orderBean.getOrderNo().equals("0007")){
            int a =3/0;
        }
        log.info("模拟发送短信");
    }
}

package com.jlwj.messageservice.listener;

import com.alibaba.fastjson.JSON;
import com.jlwj.messageservice.bean.OrderBean;
import com.rabbitmq.client.Channel;
import lombok.extern.slf4j.Slf4j;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.amqp.support.AmqpHeaders;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.messaging.handler.annotation.Header;
import org.springframework.messaging.handler.annotation.Payload;
import org.springframework.stereotype.Component;

import java.io.IOException;

/**
 * @author hehang on 2019-06-28
 * @description订单监听
 */
@Component
@Slf4j

public class DlListener {

    @Autowired
    private StringRedisTemplate stringRedisTemplate;


    @RabbitListener(queues = "dlQueue")
    public void HandlerMessage(Channel channel, Message message, @Header(AmqpHeaders.DELIVERY_TAG) long tag) throws IOException {
        log.info(new String(message.getBody()));
        //人工处理死信队列中的消息
        handlerDl(new String(message.getBody()));
        channel.basicAck(tag,false);
    }


    private void handlerDl(String message){
        log.info("发送邮件，请求人工干预:{}",message);
    }
}