SpringCloudAlibaba--Seata简单案例(一)

Seata业务数据库准备

这里会创建3个服务，一个订单服务，一个库存服务，一个账户服务。

当用户下单时，会在订单服务中创建一个订单，然后通过RPC调用库存服务来扣减下单商品的库存，再通过远程调用账户服务来扣减用户账户里面的余额，最后在订单服务中修改订单状态为已完成。

该操作跨越3个数据库，有两次远程调用，很明显会有分布式事务问题。

创建业务数据库：

• seata_order：存储订单的数据库；
• seata_storage：存储库存的数据库
• seata_account：存储账户信息的数据库

建业务表：

• seata_order库下建t_order表

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：已完成'
)ENGINE=INNODB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;

• seata_storage库下建t_storage表

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=2 DEFAULT CHARSET=utf8;

INSERT INTO t_storage VALUES(1, 1, 100, 0, 100);

• 在seata_account库下建t_account表

CREATE TABLE t_account(
	`id` BIGINT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY COMMENT 'id',
	`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 '已用余额',
	`residue` DECIMAL(10, 0) DEFAULT '0' COMMENT '剩余可用额度'
)ENGINE=INNODB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

INSERT INTO t_account VALUES(1, 1, 1000, 0, 1000);

建对应的回滚日志表：

订单、库存、账户3个库下都需要建各自的回滚日志表

-- 此脚本必须初始化在你当前的业务数据库中，用于AT模式XID记录。与server端无关
-- 增加唯一索引ux_undo_log

CREATE TABLE `undo_log` (
  `id` bigint(20) NOT NULL AUTO_INCREMENT,
  `branch_id` bigint(20) NOT NULL,
  `xid` varchar(100) NOT NULL,
  `context` varchar(128) NOT NULL,
  `rollback_info` longblob NOT NULL,
  `log_status` int(11) NOT NULL,
  `log_created` datetime NOT NULL,
  `log_modified` datetime NOT NULL,
  `ext` varchar(100) DEFAULT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `ux_undo_log` (`xid`,`branch_id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

订单/库存/账户业务微服务准备

业务需求：下订单 -> 减库存 -> 扣余额 -> 改订单状态

新建Order-Module：

1. seata-order-service2001
2. pom.xml

<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>
                    <artifactId>seata-all</artifactId>
                    <groupId>io.seata</groupId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>io.seata</groupId>
            <artifactId>seata-all</artifactId>
            <version>1.0.0</version>
        </dependency>
        <!--feign-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <!--web-actuator-->
        <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>
        <!--mysql-druid-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.37</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.10</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.0.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
    </dependencies>

3. application.yml

server:
  port: 2001

spring:
  application:
    name: seata-order-service
  cloud:
    alibaba:
      seata:
        tx-service-group: fsp_tx_group #自定义组名称，需要与seata-server中配置的对应
    nacos:
      discovery:
        server-addr: localhost:8848

  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/seata_order
    username: root
    password: 123456

feign:
  hystrix:
    enabled: false

logging:
  level: 
    io:
      seata: info
      
mybatis:
  mapperLocations: classpath:mapper/*.xml

4. file.conf

transport {
  # tcp udt unix-domain-socket
  type = "TCP"
  #NIO NATIVE
  server = "NIO"
  #enable heartbeat
  heartbeat = true
  #thread factory for netty
  thread-factory {
    boss-thread-prefix = "NettyBoss"
    worker-thread-prefix = "NettyServerNIOWorker"
    server-executor-thread-prefix = "NettyServerBizHandler"
    share-boss-worker = false
    client-selector-thread-prefix = "NettyClientSelector"
    client-selector-thread-size = 1
    client-worker-thread-prefix = "NettyClientWorkerThread"
    # netty boss thread size,will not be used for UDT
    boss-thread-size = 1
    #auto default pin or 8
    worker-thread-size = 8
  }
  shutdown {
    # when destroy server, wait seconds
    wait = 3
  }
  serialization = "seata"
  compressor = "none"
}

service {

  vgroup_mapping.fsp_tx_group = "default" #修改自定义事务组名称

  default.grouplist = "127.0.0.1:8091"
  enableDegrade = false
  disable = false
  max.commit.retry.timeout = "-1"
  max.rollback.retry.timeout = "-1"
  disableGlobalTransaction = false
}


client {
  async.commit.buffer.limit = 10000
  lock {
    retry.internal = 10
    retry.times = 30
  }
  report.retry.count = 5
  tm.commit.retry.count = 1
  tm.rollback.retry.count = 1
}

## transaction log store
store {
  ## store mode: file、db
  mode = "db"

  ## file store
  file {
    dir = "sessionStore"

    # branch session size , if exceeded first try compress lockkey, still exceeded throws exceptions
    max-branch-session-size = 16384
    # globe session size , if exceeded throws exceptions
    max-global-session-size = 512
    # file buffer size , if exceeded allocate new buffer
    file-write-buffer-cache-size = 16384
    # when recover batch read size
    session.reload.read_size = 100
    # async, sync
    flush-disk-mode = async
  }

  ## database store
  db {
    ## the implement of javax.sql.DataSource, such as DruidDataSource(druid)/BasicDataSource(dbcp) etc.
    datasource = "dbcp"
    ## mysql/oracle/h2/oceanbase etc.
    db-type = "mysql"
    driver-class-name = "com.mysql.jdbc.Driver"
    url = "jdbc:mysql://127.0.0.1:3306/seata"
    user = "root"
    password = "123456"
    min-conn = 1
    max-conn = 3
    global.table = "global_table"
    branch.table = "branch_table"
    lock-table = "lock_table"
    query-limit = 100
  }
}
lock {
  ## the lock store mode: local、remote
  mode = "remote"

  local {
    ## store locks in user's database
  }

  remote {
    ## store locks in the seata's server
  }
}
recovery {
  #schedule committing retry period in milliseconds
  committing-retry-period = 1000
  #schedule asyn committing retry period in milliseconds
  asyn-committing-retry-period = 1000
  #schedule rollbacking retry period in milliseconds
  rollbacking-retry-period = 1000
  #schedule timeout retry period in milliseconds
  timeout-retry-period = 1000
}

transaction {
  undo.data.validation = true
  undo.log.serialization = "jackson"
  undo.log.save.days = 7
  #schedule delete expired undo_log in milliseconds
  undo.log.delete.period = 86400000
  undo.log.table = "undo_log"
}

## metrics settings
metrics {
  enabled = false
  registry-type = "compact"
  # multi exporters use comma divided
  exporter-list = "prometheus"
  exporter-prometheus-port = 9898
}

support {
  ## spring
  spring {
    # auto proxy the DataSource bean
    datasource.autoproxy = false
  }
}

5. registry.conf

registry {
  # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
  type = "nacos"

  nacos {
    serverAddr = "localhost:8848"
    namespace = ""
    cluster = "default"
  }
  eureka {
    serviceUrl = "http://localhost:8761/eureka"
    application = "default"
    weight = "1"
  }
  redis {
    serverAddr = "localhost:6379"
    db = "0"
  }
  zk {
    cluster = "default"
    serverAddr = "127.0.0.1:2181"
    session.timeout = 6000
    connect.timeout = 2000
  }
  consul {
    cluster = "default"
    serverAddr = "127.0.0.1:8500"
  }
  etcd3 {
    cluster = "default"
    serverAddr = "http://localhost:2379"
  }
  sofa {
    serverAddr = "127.0.0.1:9603"
    application = "default"
    region = "DEFAULT_ZONE"
    datacenter = "DefaultDataCenter"
    cluster = "default"
    group = "SEATA_GROUP"
    addressWaitTime = "3000"
  }
  file {
    name = "file.conf"
  }
}

config {
  # file、nacos 、apollo、zk、consul、etcd3
  type = "file"

  nacos {
    serverAddr = "localhost"
    namespace = ""
  }
  consul {
    serverAddr = "127.0.0.1:8500"
  }
  apollo {
    app.id = "seata-server"
    apollo.meta = "http://192.168.1.204:8801"
  }
  zk {
    serverAddr = "127.0.0.1:2181"
    session.timeout = 6000
    connect.timeout = 2000
  }
  etcd3 {
    serverAddr = "http://localhost:2379"
  }
  file {
    name = "file.conf"
  }
}

6. domain

@Data
@AllArgsConstructor
@NoArgsConstructor
public class Order {
    
    private Long id;
    private Long userId;
    private Long productId;
    private Integer count;
    private BigDecimal money;
    
    /*
        订单状态： 0：创建中；1：已完成；
     */
    private Integer status;
}

@Data
@AllArgsConstructor
@NoArgsConstructor
public class CommonResult<T> {
    
    private Integer code;
    private String message;
    private T data;
    
    public CommonResult(Integer code, String message){
        this(code, message, null);
    }
}

7. Dao接口及实现

@Mapper
public interface OrderDao {

    //新建订单
    void create(Order order);

    //修改订单状态 0 -> 1
    void update(@Param("userId") Long userId, @Param("status") Integer status);

}

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >

<mapper namespace="pers.zhang.springcloud.alibaba.dao.OrderDao">

    <resultMap id="BaseResultMap" type="pers.zhang.springcloud.alibaba.domain.Order">
        <id column="id" property="id" jdbcType="BIGINT"/>
        <result column="user_id" property="userId" jdbcType="BIGINT"/>
        <result column="product_id" property="productId" jdbcType="BIGINT"/>
        <result column="count" property="count" jdbcType="INTEGER"/>
        <result column="money" property="money" jdbcType="DECIMAL"/>
        <result column="status" property="status" jdbcType="INTEGER"/>
    </resultMap>

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


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

</mapper>

8. Service接口及实现

public interface OrderService {
    //创建订单
    void create(Order order);
}

@Service
@Slf4j
public class OrderServiceImpl implements OrderService {

    @Resource
    OrderDao orderDao;

    @Resource
    StorageService storageService;

    @Resource
    AccountService accountService;

    @Override
    public void create(Order order) {
        log.info("------>开始新建订单");
        orderDao.create(order);
        log.info("------>订单微服务开始调用库存，扣减count");
        storageService.decrease(order.getProductId(), order.getCount());
        log.info("------>订单微服务开始调用库存，扣减end");
        log.info("------>订单微服务开始调用账户，扣减money");
        accountService.decrease(order.getUserId(), order.getMoney());
        log.info("------>订单微服务开始调用账户，扣减end");
        log.info("------>开始修改订单状态");
        orderDao.update(order.getUserId(), 0);
        log.info("------>修改订单状态完毕");
        log.info("------>下单完毕");

    }
}

@FeignClient(value = "seata-account-service")
public interface AccountService {
    //扣减账户余额
    @PostMapping(value = "/account/decrease")
    CommonResult decrease(@RequestParam("userId") Long userId, @RequestParam("money") BigDecimal money);
}

@FeignClient(value = "seata-storage-service")
public interface StorageService {
    //扣减库存
    @PostMapping(value = "/storage/decrease")
    CommonResult decrease(@RequestParam("productId") Long productId, @RequestParam("count") Integer count);
}

9. Controller

@RestController
public class OrderController
{
    @Resource
    OrderService orderService;

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

10. Config配置

@Configuration
@MapperScan({"pers.zhang.springcloud.alibaba.dao"})
public class MyBatisConfig {
}

@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();
    }

}

11. 主启动类

@EnableFeignClients
@EnableDiscoveryClient
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)//取消数据源自动创建
public class SeataOrderMainApp2001 {
    public static void main(String[] args) {
        SpringApplication.run(SeataOrderMainApp2001.class, args);
    }
}