基于SpringCloudAlibaba模拟商城下单功能

---

前言

适合刚学完Alibaba框架的同志，练练手加深印象。

---

一、功能介绍

客户下订单---->减少商品库存---->扣用户余额---->最后修改订单的状态

二、概念图

三、实操

1.数据库

订单表（示例）：

CREATE DATABASE seata_order;
USE seata_order;
CREATE TABLE t_order(
    id BIGINT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY ,
    user_id BIGINT(11) DEFAULT NULL COMMENT '用户id',
    product_id BIGINT(11) DEFAULT NULL COMMENT '产品id',
    count INT(11) DEFAULT NULL COMMENT '数量',
    money DECIMAL(11,0) DEFAULT NULL COMMENT '金额',
    status INT(1) DEFAULT NULL COMMENT '订单状态：0创建中，1已完结'
)ENGINE=InnoDB AUTO_INCREMENT=7 CHARSET=utf8;

用户余额表（示例）：

CREATE DATABASE seata_account;
USE seata_account;
CREATE TABLE t_account(
    id BIGINT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY ,
    user_id BIGINT(11) DEFAULT NULL COMMENT '用户id',
    total DECIMAL(10,0) DEFAULT NULL COMMENT '总额度',
    used DECIMAL(10,0) DEFAULT NULL COMMENT '已用额度',
    residue DECIMAL(10,0) DEFAULT 0 COMMENT '剩余可用额度'
)ENGINE=InnoDB AUTO_INCREMENT=7 CHARSET=utf8;
INSERT INTO t_account(id, user_id, total, used, residue) VALUES(1,1,1000,0,1000);

库存表（示例）：

CREATE DATABASE seata_storage;
USE seata_storage;
CREATE TABLE t_storage(
    id BIGINT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY ,
    product_id BIGINT(11) DEFAULT NULL COMMENT '产品id',
    total INT(11) DEFAULT NULL COMMENT '总库存',
    used INT(11) DEFAULT NULL COMMENT '已用库存',
    residue INT(11) DEFAULT NULL COMMENT '剩余库存'
)ENGINE=InnoDB AUTO_INCREMENT=7 CHARSET=utf8;
INSERT INTO t_storage(id, product_id, total, used, residue) VALUES(1,1,100,0,100);

每个数据库创建一个回滚日志表

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;

-- ----------------------------
-- Table structure for undo_log
-- ----------------------------
DROP TABLE IF EXISTS `undo_log`;
CREATE TABLE `undo_log`  (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `branch_id` bigint(20) NOT NULL,
  `xid` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
  `context` varchar(128) CHARACTER SET utf8 COLLATE utf8_general_ci NOT NULL,
  `rollback_info` longblob NOT NULL,
  `log_status` int(11) NOT NULL,
  `log_created` datetime(0) NOT NULL,
  `log_modified` datetime(0) NOT NULL,
  `ext` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
  PRIMARY KEY (`id`) USING BTREE,
  UNIQUE INDEX `ux_undo_log`(`xid`, `branch_id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 1 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;

-- ----------------------------
-- Records of undo_log
-- ----------------------------

SET FOREIGN_KEY_CHECKS = 1;

2.先启动nacos再启动seata！！！

3.订单服务模块(相当于消费者)

新建一个cloudalibaba-seata-order2001模块

POM：

    <dependencies>
        <!-- nacos -->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        <!-- nacos -->

        <!-- seata-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>io.seata</groupId>
                    <artifactId>seata-all</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>io.seata</groupId>
            <artifactId>seata-all</artifactId>
            <version>1.0.0</version>
        </dependency>
        <!-- seata-->
        <!--feign-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </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>
        </dependency>
</project>

YML：

server:
  port: 2001
spring:
  application:
    name: seata-order-service
  cloud:
    alibaba:
      seata:
        tx-service-group: zng  # 自定义事务组，需要和 seata/conf/file.conf 中的一致
    nacos:
      discovery:
        server-addr: localhost:8848
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/seata_order
    username: root
    password: root

mybatis:
  mapperLocations: classpath:mapper/*.xml	# 注意，这是自定义的，原来的是mapper_locations

logging:
  level:
    io:
      seata: info

feign:
  hystrix:
    enabled: false # 不使用豪猪哥

主启动：

//排除数据源自动配置，让seata管理数据源
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
@EnableDiscoveryClient//服务发现
@EnableFeignClients//激活feign
@MapperScan("com.zng.springcloud.mapper")//自动扫描mapper，不用在头上添加@mapper注解了
public class SeataOrderMain2001 {
    public static void main(String[] args) {
        SpringApplication.run(SeataOrderMain2001.class, args);
    }
}

配置druid数据源：

@Configuration
public class DataSourceProxyConfig {

    @Value("${mybatis.mapperLocations}")
    private String mapperLocations;

    @Bean
    @ConfigurationProperties(prefix = "spring.datasource")
    public DataSource druidDataSource(){
        return new DruidDataSource();
    }

    @Bean
    public DataSourceProxy dataSourceProxy(DataSource dataSource){
        return new DataSourceProxy(dataSource);
    }

    @Bean
    public SqlSessionFactory sqlSessionFactoryBean(DataSourceProxy dataSourceProxy) throws Exception {
        SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        sqlSessionFactoryBean.setDataSource(dataSourceProxy);
        sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(mapperLocations));
        sqlSessionFactoryBean.setTransactionFactory(new SpringManagedTransactionFactory());
        return sqlSessionFactoryBean.getObject();
    }
}

模型Model:

package com.zng.springcloud.domain;


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

@Data
@AllArgsConstructor
@NoArgsConstructor
public class Order {

    private Long id;
    private Long userId;
    private Long productId;
    private Integer count;
    private Integer money;
    private Integer status;

}

@Data
@NoArgsConstructor
@AllArgsConstructor
public class CommonResult<T> {

    private Integer code; //状态码
    private String message; //信息
    private T data;

    public CommonResult(Integer code, String message){
        this(code, message, null);
    }

}

控制访问层Controller：

@RestController
public class OrderController {

    @Autowired
    private OrderService orderService;

    @GetMapping("/order/create")
    public CommonResult<String> create(Order order){
        orderService.create(order);
        return new CommonResult<>(200, "创建成功");
    }

}

利用Feign调用库存和用户余额服务：

@FeignClient(value = "seata-storage-service")
@Component
public interface StorageService { //库存服务

    @PostMapping("/storage/decrease")
    CommonResult storage(@RequestParam("productId") Long productId, @RequestParam("count") Integer count);

}

@FeignClient(value = "seata-account-service")
@Component
public interface AccountService { //用户余额服务

    @PostMapping("/account/decrease")
    CommonResult account(@RequestParam("id") Long userId, @RequestParam("money") Integer money);

}

主体业务层

@Service
@Slf4j
public class OrderServiceImpl implements OrderService {

    @Resource
    private OrderMapper orderMapper;

    @Resource
    private StorageService storageService;

    @Resource
    private AccountService accountService;

    @Override
    public void create(Order order) {

        int i = orderMapper.create(order);
        if (i == 0){
            log.info("创建订单失败，请稍后再试");
        }

        log.info("订单完成后减库存");
        storageService.storage(order.getProductId(), order.getCount());

        log.info("订单完成后减余额");
        accountService.account(order.getUserId(), order.getMoney());

        log.info("订单完成后修改状态");
        orderMapper.state(order.getProductId(), order.getStatus());
    }

}

Mapper层

public interface OrderMapper {

    //创建订单
    int create(Order order);

    //修改状态
    void state(@Param("userId") Long userId, @Param("status") Integer status);

}

<mapper namespace="com.zng.springcloud.mapper.OrderMapper">

    <!--结果集映射(扩展可以用到)-->
    <resultMap id="BaseResultMap" type="com.zng.springcloud.domain.Order">
        <id column="id" property="id" />
        <result column="user_id" property="userId" />
        <result column="product_id" property="productId" />
        <result column="count" property="count" />
        <result column="money" property="money" />
        <result column="status" property="status" />
    </resultMap>


    <insert id="create">
        insert into t_order values (null,#{userId},#{productId},#{count},#{money},0)
    </insert>

    <update id="state">
        update t_order set status=1 where user_id=#{userId} and status=#{status}
    </update>

</mapper>

注意事项：

seata的配置文件拷贝过来放入Resources中，不然启动不了！！！！

4.库存与余额服务模块（被调用的一方）

POM(没什么区别就少了Feign)

<?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>cloud</artifactId>
        <groupId>com.zng.springcloud</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>cloudalibaba-serve-storage3001</artifactId>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>

    <dependencies>
        <!-- nacos -->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        <!-- seata-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>io.seata</groupId>
                    <artifactId>seata-all</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>io.seata</groupId>
            <artifactId>seata-all</artifactId>
            <version>1.0.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </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>
        </dependency>
        <dependency><!-- 引入自己定义的api通用包，可以使用Payment支付Entity -->
            <groupId>com.zng.springcloud</groupId>
            <artifactId>cloud-api-commons</artifactId>
            <version>1.0-SNAPSHOT</version>
        </dependency>
    </dependencies>
</project>

YML：

server:
  port: 3002
spring:
  application:
    name: seata-account-service
  cloud:
    alibaba:
      seata:
        # 自定义事务组
        tx-service-group: zng
    nacos:
      discovery:
        server-addr: localhost:8848
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/seata_account
    username: root
    password: root


# 注意，这是自定义的，原来的是mapper_locations
mybatis:
  mapperLocations: classpath:mapper/*.xml

logging:
  level:
    io:
      seata: info

访问层

@RestController
public class AccountController {

    @Autowired
    private AccountService accountService;

    @RequestMapping("/account/decrease")
    public CommonResult<String> decrease(Long id, Integer money){
        accountService.reduce(id, money);
        return new CommonResult<String>(200, "余额扣减成功");
    }
}

Mapper层

<mapper namespace="com.zng.springcloud.mapper.AccountMapper">

    <!--下订单，减余额-->
    <update id="reduce">

        update t_account set used = used + #{money}, residue = residue - #{money} where user_id=#{id}

    </update>

</mapper>

注意事项：

同样的seata的配置文件拷贝过来放入Resources中，不然启动不了！！！！

四、测试

正常访问:

正常访问是没问题的

那如果是高并发的情况下导致调用过程延迟呢？？？我们模拟余额服务模块延迟的情况会怎么样

结果：

原因：Fegin默认超时超过1s会直接抛异常

解决分布式事务的问题：@GlobalTransactional注解·

@Override
    //在业务类的方法上加上该注解，name值自定义唯一即可。rollbackFor=回滚类型
    @GlobalTransactional(name = "zng", rollbackFor = Exception.class)//分布式事务回滚
    public void create(Order order) {

        int i = orderMapper.create(order);
        if (i == 0){
            log.info("创建订单失败，请稍后再试");
        }

        log.info("订单完成后减库存");
        storageService.storage(order.getProductId(), order.getCount());

        log.info("订单完成后减余额");
        accountService.account(order.getUserId(), order.getMoney());

        log.info("订单完成后修改状态");
        orderMapper.state(order.getProductId(), order.getStatus());
    }