IDEA SpringBoot+JPA+MySql+Redis+RabbitMQ 秒杀系统

先放上github地址：spike-system，可以直接下载完整项目运行测试

SpringBoot+JPA+MySql+Redis+RabbitMQ 秒杀系统

技术栈：SpringBoot, MySql, Redis, RabbitMQ, JPA,(lombok)

Controller

/put : 上架 "watch"商品10个

@RequestMapping("/put")
    	String put(@RequestParam String orderName, @RequestParam Long count)

/sec : 秒杀购买商品

    @RequestMapping("/sec")  
    	String sec(String userName, String orderName)

Guide

项目参考自
入门基础必备，使用Idea实现SpringBoot+Mysql+Redis+RabbitMQ+Jmeter模拟实现高并发秒杀
简化了原项目，将tkmybatis替换成JPA。并将一些比较复杂的操作尽可能简化。

项目结构

		│  MainSystemApplication.java
		│
		├─config
		│      MyRabbitConfig.java
		│      MyRedisConfig.java
		│
		├─controller
		│      Test.java
		│
		├─dao
		│      StockRe.java
		│      TOrderRe.java
		│
		├─domain
		│      Stock.java
		│      TOrder.java
		│
		└─service
				MQOrderService.java
				MQStockService.java
				RedisService.java

说明

stock代表库存，TORder代表订单。当一个购买行为发生时，应用会先查询购买物品的库存是否足够，如果足够，则将库存减一，并生成一个订单数据到数据库保存，最后返回购买成功的消息给用户

START

首先利用idea创建springboot项目时勾选lombokweb edisRabbitMQMySqlJPA，生成的pom依赖如下

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.springframework.amqp</groupId>
            <artifactId>spring-rabbit-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
    </dependencies>

首先要创建两个实体类到domain包下

package com.chunmiao.mainsystem.domain;

import lombok.Data;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import java.io.Serializable;

/**
 * 库存实体类
 */
@Data
@Entity
public class Stock implements Serializable {
    @Id
    @GeneratedValue
    private Long id;

    private String name;

    //货品库存数量
    private Long stock;

}

---

package com.chunmiao.mainsystem.domain;

import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import java.io.Serializable;

/**
 * 订单实体类
 */
@Data
@Entity
@Builder
@NoArgsConstructor
@AllArgsConstructor
public class TOrder implements Serializable{
    @Id
    @GeneratedValue
    private Long id;

    private String orderName;

    private String orderUser;

}

---

然后创建jpa的Repository到dao包下。
jpa实现crud的操作只需要继承JPARepository接口即可自动提供findsavadelete实现类给用户使用。

package com.chunmiao.mainsystem.dao;

import com.chunmiao.mainsystem.domain.TOrder;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface TOrderRe extends JpaRepository<TOrder,Long> {
}

---

由于JPA默认只提供findById的操作，如果想通过别的字段查询需要自己提供接口，当然，JPA也会为这个接口自动提供实现类

package com.chunmiao.mainsystem.dao;

import com.chunmiao.mainsystem.domain.Stock;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface StockRe extends JpaRepository<Stock,Long> {

    Stock findByName(String name);

}

然后创建config包，配置RabbitMQ和Redis.
RabbitMQ这里涉及到交换机、队列、路由键的概念，需要搜索RabbitMQ基础教程了解一下

package com.chunmiao.mainsystem.config;

import org.springframework.amqp.core.*;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MyRabbitConfig {

    public final static String TORDER_EXCHANG = "TORDER_EXCHANG";

    public final static String TORDER_QUEUE = "TORDER_QUEUE";

    public final static String TORDER_ROUTING_KEY = "TORDER_ROUTING_KEY";

    public final static String STOCK_EXCHANG = "STOCK_EXCHANG";

    public final static String STOCK_QUEUE = "STOCK_QUEUE";

    public final static String STOCK_ROUTING_KEY = "STOCK_ROUTING_KEY";

    /**
     * 订单消息
     * 1.创建交换机
     * 2.创建队列
     * 3.通过路由键绑定交换机和队列
     */
    @Bean
    public Exchange getTOrderExchang() {
        return ExchangeBuilder.directExchange(TORDER_EXCHANG).build();
    }

    @Bean
    public Queue getTOrderQueue() {
        return QueueBuilder.nonDurable(TORDER_QUEUE).build();
    }

    @Bean
    public Binding bindTOrder() {
        return BindingBuilder.bind(getTOrderQueue()).to(getTOrderExchang()).with(TORDER_ROUTING_KEY).noargs();
    }

    /**
     * 库存消息
     * 1.创建交换机
     * 2.创建队列
     * 3.通过路由键绑定交换机和队列
     */
    @Bean
    public Exchange getStockExchange() {
        return ExchangeBuilder.directExchange(STOCK_EXCHANG).build();
    }

    @Bean
    public Queue getStockQueue() {
        return QueueBuilder.nonDurable(STOCK_QUEUE).build();
    }

    @Bean
    public Binding bindStock() {
        return BindingBuilder.bind(getStockQueue()).to(getStockExchange()).with(STOCK_ROUTING_KEY).noargs();
    }

}

---

Redis的配置主要是序列化的配置，应该不配置也可以的。但是配置后查看的时候更美观，而且性能会更好更简洁。

package com.chunmiao.mainsystem.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;

@Configuration
public class MyRedisConfig {

    @Bean
    public RedisTemplate<String,Object> redisTemplate(RedisConnectionFactory redisConnectionFactory){
        RedisTemplate<String, Object> re = new RedisTemplate<>();
        re.setConnectionFactory(redisConnectionFactory);
        re.setKeySerializer(new StringRedisSerializer());
        re.setValueSerializer(new Jackson2JsonRedisSerializer<>(Long.class));   // 不能用generic的Serializer，有存Long取Integer的bug
        re.afterPropertiesSet();
        return re;
    }


}

---

然后到Service层，逻辑是RedisService提供增加库存、查询库存服务，增加库存时需要调用StockRe保存增加库存到数据库。

package com.chunmiao.mainsystem.service;

import com.chunmiao.mainsystem.dao.StockRe;
import com.chunmiao.mainsystem.domain.Stock;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.BoundValueOperations;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Service;

/**
 * stock信息缓存到redis
 */
@Service
public class RedisService {
    @Autowired
    private RedisTemplate<String, Object> redisTemplate;
    @Autowired
    private StockRe stockRe;

    public void put(String key, Long value) {
        BoundValueOperations<String, Object> bp = redisTemplate.boundValueOps(key);
        Long count = (Long) bp.get();
        if ( count!= null){
            count = count >= 0 ? count + value : value;
        } else count = value;
        bp.set(count);

        Stock stock = stockRe.findByName(key);
        if (stock == null) {
            stock = new Stock();
            stock.setName(key);
            stock.setStock(0l);
        }
        long l = stock.getStock() + value;
        stock.setStock(l);
        stockRe.save(stock);
    }
	// 返回当前商品库存-1的结果，如果库存小于0时直接返回，这样调用它的类就知道已经没有库存了
    public Long decrBy(String key) {
        BoundValueOperations<String, Object> bp = redisTemplate.boundValueOps(key);
        Long count = (Long) bp.get();
        if (count == null) return -1l;
        if (count >= 0) {
            count--;
            bp.set(count);
        }
        return count;
    }
}

---

MQOrderService用于消费队列中的订单消息，创建新订单保存到数据库。只需要使用@RabbitMQListener即可实现监听

package com.chunmiao.mainsystem.service;

import com.chunmiao.mainsystem.dao.TOrderRe;
import com.chunmiao.mainsystem.domain.TOrder;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import static com.chunmiao.mainsystem.config.MyRabbitConfig.TORDER_QUEUE;
import static com.chunmiao.mainsystem.config.MyRabbitConfig.STOCK_QUEUE;

/**
 * 从MQ中拿消息，创建一个新订单到数据库
 */
@Service
public class MQOrderService {
    @Autowired
    private TOrderRe orderRe;

    @RabbitListener(queues = TORDER_QUEUE)
    public void saveOrder(TOrder order) {
        System.out.println("创建新订单");
        orderRe.save(order);
    }
}

---

同理，监听库存消息并修改数据库值

package com.chunmiao.mainsystem.service;

import com.chunmiao.mainsystem.dao.StockRe;
import com.chunmiao.mainsystem.domain.Stock;
import org.springframework.amqp.rabbit.annotation.RabbitListener;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import static com.chunmiao.mainsystem.config.MyRabbitConfig.STOCK_QUEUE;

/**
 * 从MQ拿消息，使库存减少一个
 */
@Service
public class MQStockService {
    @Autowired
    private StockRe stockRe;

    @RabbitListener(queues = STOCK_QUEUE)
    public void decrStock(String orderName) {
        System.out.println("减少数据库的库存");
        Stock stock = stockRe.findByName(orderName);
        if (stock!= null) {
            stock.setStock(stock.getStock() - 1);
            stockRe.save(stock);
        }
    }
}

---

最后一个类，controller，提供接口。购买逻辑是直接调用redisService提供的方法，实现操作 库存-1，返回该结果，如果结果>=0说明库存充足，发送创建新订单和库存-1消息给RabbitMQ，然后直接返回购买成功的结果给用户即可；如果库存不足，直接返回购买失败即可。使用RabbitMQ的好处是，只需要关心是否有库存，然后简单的发送消息之后就不用再管了，同时做到了削峰的好处

package com.chunmiao.mainsystem.controller;


import com.chunmiao.mainsystem.domain.TOrder;
import com.chunmiao.mainsystem.service.RedisService;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import static com.chunmiao.mainsystem.config.MyRabbitConfig.*;

@RestController
public class Test {
    @Autowired
    private RedisService redisService;

    @Autowired
    private RabbitTemplate rabbitTemplate;

    @RequestMapping("/put")
    String put(@RequestParam String orderName, @RequestParam Long count) {
        redisService.put(orderName, count);
        return "上架商品
" + orderName + ":" + count;
    }

    @RequestMapping("/sec")
    String sec(String userName, String orderName) {
        String msg = "秒杀用户：" + userName + "
" + "秒杀商品： " + orderName;
        System.out.println("
---------------------------------------------");
        System.out.println("秒杀用户：" + userName + "
" + "秒杀商品： " + orderName);
        Long count = redisService.decrBy(orderName);
        // 秒杀成功
        System.out.println("当前商品数量为： " + (count + 1));
        if (count >= 0) {
            System.out.println("库存充足");
            // 创建新订单
            rabbitTemplate.convertAndSend(TORDER_EXCHANG,TORDER_ROUTING_KEY,
                    TOrder.builder()
                            .orderName(orderName)
                            .orderUser(userName)
                            .build());
            // 创建库存-1消息
            rabbitTemplate.convertAndSend(STOCK_EXCHANG,STOCK_ROUTING_KEY,orderName);
            System.out.println("秒杀成功");
            msg +=  "成功";
        } else {
            System.out.println("库存不足");
            msg += "失败";
        }
        return msg;
    }
}

最后可以运行起来，先put一个商品进去，再利用Jmeter进行压力测试，Jmeter的使用可以参考本文参考的文章。