Seata 入门教程 - 实战篇（2024 年）

大纲

• Seata 入门教程 - 基础篇（2020 年）
• Seata 入门教程 - 中级篇（2020 年）
• Seata 入门教程 - 实战篇（2020 年）
• Seata 入门教程 - 实战篇（2024 年）

前言

官方资源

• Seata GitHub
• Seata 官方文档
• Seata 官方示例代码

实战案例一

1、案例说明

本案例是电商实战项目，使用了 Seata 的 AT 模式，并基于 Seata 分布式交易解决方案（如下图所示）。

1.1、版本说明

在本文的所有案例中，各个组件统一使用以下版本：

组件	版本	说明
MySQL	8.4.2
Nacos Server	2.4.3
Seata Server（TC）	2.2.0
Spring Boot	3.2.9
Spring Cloud	2023.0.1
Spring Cloud Alibaba	2023.0.1.3

若希望降低 SpringBoot 与 Spring Cloud 的版本，可以尝试以下版本组合（仅供参考）：

组件	版本组合一	版本组合二	说明
MySQL	8.4.2	8.4.2
Nacos Server	2.2.3	2.2.3
Seata Server（TC）	2.0.0	2.0.0
Spring Boot	3.1.7	3.0.9
Spring Cloud	2022.0.4	2022.0.2
Spring Cloud Alibaba	2022.0.0.0	2022.0.0.0

特别注意

Spring Boot 和 Spring Cloud 以及 Spring Cloud Alibaba 的版本号需要互相匹配，还有 Seata Server（TC）的版本也要匹配，否则可能会存在各种兼容问题，具体可以参考官方的版本说明。

1.2、案例目标

本案例将创建三个服务，分别是订单服务、库存服务、账户服务，各服务之间的调用流程如下：

• 1）当用户下单时，调用订单服务创建一个订单，然后通过远程调用（OpenFeign）让库存服务扣减下单商品的库存
• 2）订单服务再通过远程调用（OpenFeign）让账户服务来扣减用户账户里面的余额
• 3）最后在订单服务中修改订单状态为已完成

上述操作跨越了三个数据库，有两次远程调用，很明显会有分布式事务的问题，项目的整体结构如下：

seata-transaction-demo
├── seata-common-api          # API模块
├── seata-account-service     # 账户模块，端口：8085
├── seata-storage-service     # 库存模块，端口：8086
└── seata-order-service       # 订单模块，端口：8087

1.3、代码下载

• 由于篇幅有限，本案例只给出各个模块的核心代码和配置，完整的案例代码可以从 这里 下载得到。

2、准备工作

2.1、安装 Seata

• Docker 安装单机版的 Seata

特别注意

严格根据上述的教程内容，通过 Docker 安装好 Seata Server（TC）后，可能需要额外执行以下步骤，保证 SpringBoot 应用（即 Seata Client）可以正常连接 Seata Server（TC）。

若 Spring Boot 应用不是部署 Docker 容器内（即与 Seata 容器处于不同的网络），那么在 docker-compose.yml 文件中，需要添加 SEATA_IP 环境变量来指定 Seata Server（TC） 注册到 Nacos 注册中心的 IP 地址，并且这里的 IP 地址必须是 SpringBoot 应用可以正常访问的（比如指定为宿主机的 IP），否则 Docker 容器外的 SpringBoot 应用在启动时会无法连接 Seata Server（TC），导致启动失败。配置示例如下：

version: '3.5'

service:

  seata:
    image: seataio/seata-server:2.0.0
    container_name: spring-cloud-2024-seata-server
    restart: always
    ports:
      - 8091:8091
      - 7091:7091
    environment:
      - SEATA_IP=127.0.0.1     # 指定 Seata Server（TC）注册到 Nacos 注册中心的 IP 地址
      - SEATA_PORT=8091
      - TZ=Asia/Shanghai
    volumes:
      - /usr/local/docker/docker-volumes/seata/config/resources:/seata-server/resources
      - /usr/local/docker/docker-volumes/seata/logs:/var/log/seata
    depends_on:
      mysql8:
        condition: service_healthy
      nacos:
        condition: service_healthy
    networks:
      - cloud-network

2.2、初始化数据库

这里使用 MySQL 数据库来存储 Seata Server（TC）的全局事务会话信息，因此需要执行 SQL 初始化脚本（完整） 来创建 Seata 所需的数据库，还有业务所需的数据库。由于 Seata 的 AT 模式需要用到 UNDO_LOG 回滚日志表，因此在每个业务数据库里都要单独创建 UNDO_LOG 回滚日志表，最终所有用到的数据库和业务表如下图所示：

提示

• 针对 Seata 2.x 版本，Seata Server（TC）所需的多个表结构可以从 这里 获取得到。
• 针对 Seata 2.x 版本，Seata Client 所需的 UNDO_LOG 表结构可以从 这里 获取得到。

2.3、初始化 Nacos 配置

在 Nacos 配置中心里面，添加 Seata Client 所需的配置信息，SpringBoot 应用（即 Seata Client）在启动时会读取相应的配置信息，如下图所示：

• 命名空间： public
• 分组名称: SEATA_GROUP
• Data ID：seata-client.properties
• 配置信息：service.vgroupMapping.default_tx_group=default

3、创建 Maven 父工程

创建 Maven 父工程，配置好工程需要的父级依赖，目的是为了更方便管理与简化配置。

<modules>
    <module>seata-order-service</module>
    <module>seata-storage-service</module>
    <module>seata-account-service</module>
    <module>seata-common-api</module>
</modules>

<properties>
    <mysql.version>8.0.11</mysql.version>
    <druid.version>1.1.20</druid.version>
    <mybatis.springboot.version>3.0.3</mybatis.springboot.version>
    <fastjson2.version>2.0.40</fastjson2.version>
    <hutool.version>5.8.22</hutool.version>
    <lombok.version>1.18.26</lombok.version>
    <spring.boot.version>3.2.9</spring.boot.version>
    <spring.cloud.version>2023.0.1</spring.cloud.version>
    <spring.cloud.alibaba.version>2023.0.1.3</spring.cloud.alibaba.version>
    <spring.boot.test.version>3.1.5</spring.boot.test.version>
</properties>

<dependencyManagement>
    <dependencies>
        <!--SpringBoot-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-dependencies</artifactId>
            <version>${spring.boot.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
        <!--SpringCloud-->
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-dependencies</artifactId>
            <version>${spring.cloud.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
        <!--SpringCloud Alibaba-->
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-alibaba-dependencies</artifactId>
            <version>${spring.cloud.alibaba.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
        <!--MySQL数据库驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>${mysql.version}</version>
        </dependency>
        <!--Druid-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>${druid.version}</version>
        </dependency>
        <!--MyBatis-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>${mybatis.springboot.version}</version>
        </dependency>
        <!--Fastjson2-->
        <dependency>
            <groupId>com.alibaba.fastjson2</groupId>
            <artifactId>fastjson2</artifactId>
            <version>${fastjson2.version}</version>
        </dependency>
        <!--HuTool-->
        <dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-all</artifactId>
            <version>${hutool.version}</version>
        </dependency>
        <!--Lombok-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>${lombok.version}</version>
            <optional>true</optional>
        </dependency>
        <!--SpringBoot Test-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <version>${spring.boot.test.version}</version>
            <scope>test</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

4、创建订单工程

4.1、创建 pom.xml

订单工程的 Maven 配置内容如下：

<dependencies>
    <!--seata-common-api-->
    <dependency>
        <groupId>com.clay</groupId>
        <artifactId>seata-common-api</artifactId>
        <version>1.0-SNAPSHOT</version>
    </dependency>
    <!--Web-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <!--Actuator-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <!--OpenFeign-->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-openfeign</artifactId>
    </dependency>
    <!--LoadBalancer-->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-loadbalancer</artifactId>
    </dependency>
    <!--Nacos Discovery-->
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
    </dependency>
    <!--Nacos Config-->
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-bootstrap</artifactId>
    </dependency>
    <!--Seata-->
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
    </dependency>
    <!--MySQL数据库驱动-->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
    </dependency>
    <!--Druid-->
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid-spring-boot-starter</artifactId>
    </dependency>
    <!--MyBatis-->
    <dependency>
        <groupId>org.mybatis.spring.boot</groupId>
        <artifactId>mybatis-spring-boot-starter</artifactId>
    </dependency>
    <!--Fastjson2-->
    <dependency>
        <groupId>com.alibaba.fastjson2</groupId>
        <artifactId>fastjson2</artifactId>
    </dependency>
    <!--HuTool-->
    <dependency>
        <groupId>cn.hutool</groupId>
        <artifactId>hutool-all</artifactId>
    </dependency>
    <!--Lombok-->
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <optional>true</optional>
    </dependency>
</dependencies>

4.2、创建 application.yml

提示

Seata Server（TC） 从 1.5.0 版本开始，配置文件改为 application.yml，同时向下兼容旧的 register.conf 和 file.conf 两个配置文件。

server:
  port: 8085

spring:
  application:
    name: seata-order-service

  # 注册中心
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848

  # 数据源
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/seata_order?characterEncoding=utf8&useSSL=false&serverTimezone=GMT%2B8&rewriteBatchedStatements=true&allowPublicKeyRetrieval=true
    username: seata
    password: seata

  # Druid 连接池
  druid:
    initial-size: 5
    min-idle: 5
    max-active: 20
    max-wait: 60000
    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
    pool-prepared-statements: true
    max-pool-prepared-statement-per-connection-size: 20
    filters: stat,wall,log4j
    connection-properties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000

# MyBatis
mybatis:
  mapper-locations: classpath*:mybatis/mapper/*.xml
  type-aliases-package: com.clay.entities
  configuration:
    map-underscore-to-camel-case: true

# Seata
seata:
  # 指定从 Nacos 注册中心获取 Seata Server（TC）的地址
  registry:
    type: nacos
    nacos:
      application: seata-server # Seata Server（TC）的服务名称
      server-addr: 127.0.0.1:8848
      namespace:
      group: SEATA_GROUP
      cluster: default
  # 指定从 Nacos 配置中心获取 Seata Client 的配置信息
  config:
    type: nacos
    nacos:
      server-addr: 127.0.0.1:8848
      namespace:
      group: SEATA_GROUP
      data-id: seata-client.properties
      username:
      password:
  tx-service-group: default_tx_group # 事务组，由它获得 Seata Server（TC）服务的集群名称
  service:
    vgroup-mapping:
      default_tx_group: default # 事务组与 Seata Server（TC）服务集群的映射关系
  data-source-proxy-mode: AT
  application-id: ${spring.application.name}

# 日志
logging:
  level:
    io:
      seata: info

4.3、添加全局事务注解

在订单创建的入口方法上面添加 @GlobalTransactional 来控制分布式事务，这里使用 OpenFeign 去调用库存服务和账户服务的接口

@Slf4j
@Service
public class OrderServiceImpl implements OrderService {

    @Resource
    private OrderMapper orderMapper;

    @Resource
    private StorageFeignApi storageFeignApi;

    @Resource
    private AccountFeignApi accountFeignApi;

    @Override
    @GlobalTransactional(name = "seata-create-order", rollbackFor = Exception.class)
    public ResultData create(Order order) {
        // 查看 Seata 的 XID
        String xid = RootContext.getXID();
        log.info("==================>开始创建订单" + "\t" + "xid: " + xid);

        // 1. 插入订单
        order.setStatus(0);
        int result = orderMapper.insert(order);

        Order orderFromDB = null;
        if (result > 0) {
            // 插入订单成功后，获取插入MySQL的订单实体对象
            orderFromDB = orderMapper.selectById(order.getId());
            log.info("-------> 创建订单成功，orderFromDB info: " + orderFromDB);
            System.out.println();

            // 2. 扣减库存
            log.info("-------> 订单微服务开始调用Storage库存服务，开始扣减库存");
            ResultData storageResult = storageFeignApi.decrease(orderFromDB.getProductId(), orderFromDB.getCount());
            Assert.isTrue(storageResult.isSuccess(), storageResult.getMessage());
            log.info("-------> 订单微服务结束调用Storage库存服务，扣减库存完成");
            System.out.println();

            // 3. 扣减账户余额
            log.info("-------> 订单微服务开始调用Account账户服务，开始扣减账户余额");
            ResultData accountResult = accountFeignApi.decrease(orderFromDB.getUserId(), orderFromDB.getMoney());
            Assert.isTrue(accountResult.isSuccess(), accountResult.getMessage());
            log.info("-------> 订单微服务结束调用Account账户服务，扣减账户余额完成");
            System.out.println();

            // 4. 修改订单状态
            log.info("-------> 开始修改订单状态");
            int updateResult = orderMapper.updateStatus(orderFromDB.getId(), 1);
            log.info("-------> 修改订单状态完成" + "\t" + "修改结果： " + updateResult);
        } else {
            log.info("-------> 订单创建失败");
        }

        System.out.println();
        log.info("==================>结束创建订单" + "\t" + "xid: " + xid);

        return ResultData.success(orderFromDB);
    }

}

4.4、创建主启动类

@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients
@MapperScan("com.clay.mapper")
public class SeataOrderApplication {

    public static void main(String[] args) {
        SpringApplication.run(SeataOrderApplication.class, args);
    }

}

5. 创建库存工程

5.1、创建 pom.xml

库存工程的 Maven 配置内容如下：

<dependencies>
    <!--seata-common-api-->
    <dependency>
        <groupId>com.clay</groupId>
        <artifactId>seata-common-api</artifactId>
        <version>1.0-SNAPSHOT</version>
    </dependency>
    <!--Web-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <!--Actuator-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <!--OpenFeign-->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-openfeign</artifactId>
    </dependency>
    <!--LoadBalancer-->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-loadbalancer</artifactId>
    </dependency>
    <!--Nacos Discovery-->
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
    </dependency>
    <!--Nacos Config-->
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-bootstrap</artifactId>
    </dependency>
    <!--Seata-->
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
    </dependency>
    <!--MySQL数据库驱动-->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
    </dependency>
    <!--Druid-->
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid-spring-boot-starter</artifactId>
    </dependency>
    <!--MyBatis-->
    <dependency>
        <groupId>org.mybatis.spring.boot</groupId>
        <artifactId>mybatis-spring-boot-starter</artifactId>
    </dependency>
    <!--Fastjson2-->
    <dependency>
        <groupId>com.alibaba.fastjson2</groupId>
        <artifactId>fastjson2</artifactId>
    </dependency>
    <!--HuTool-->
    <dependency>
        <groupId>cn.hutool</groupId>
        <artifactId>hutool-all</artifactId>
    </dependency>
    <!--Lombok-->
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <optional>true</optional>
    </dependency>
</dependencies>

5.2、创建 application.yml

server:
  port: 8086

spring:
  application:
    name: seata-storage-service

  # 注册中心
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848

  # 数据源
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/seata_storage?characterEncoding=utf8&useSSL=false&serverTimezone=GMT%2B8&rewriteBatchedStatements=true&allowPublicKeyRetrieval=true
    username: seata
    password: seata

  # Druid 连接池
  druid:
    initial-size: 5
    min-idle: 5
    max-active: 20
    max-wait: 60000
    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
    pool-prepared-statements: true
    max-pool-prepared-statement-per-connection-size: 20
    filters: stat,wall,log4j
    connection-properties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000

# MyBatis
mybatis:
  mapper-locations: classpath*:mybatis/mapper/*.xml
  type-aliases-package: com.clay.entities
  configuration:
    map-underscore-to-camel-case: true

# Seata
seata:
  # 指定从 Nacos 注册中心获取 Seata Server（TC）的地址
  registry:
    type: nacos
    nacos:
      application: seata-server # Seata Server（TC）的服务名称
      server-addr: 127.0.0.1:8848
      namespace:
      group: SEATA_GROUP
      cluster: default
  # 指定从 Nacos 配置中心获取 Seata Client 的配置信息
  config:
    type: nacos
    nacos:
      server-addr: 127.0.0.1:8848
      namespace:
      group: SEATA_GROUP
      data-id: seata-client.properties
      username:
      password:
  tx-service-group: default_tx_group # 事务组，由它获得 Seata Server（TC）服务的集群名称
  service:
    vgroup-mapping:
      default_tx_group: default # 事务组与 Seata Server（TC）服务集群的映射关系
  data-source-proxy-mode: AT
  application-id: ${spring.application.name}

# 日志
logging:
  level:
    io:
      seata: info

5.3、创建业务处理类

@Service
@Slf4j
public class StorageServiceImpl implements StorageService {

    @Resource
    private StorageMapper storageMapper;

    @Override
    public ResultData decrease(Long productId, Integer count) {
        Storage storage = storageMapper.selectByProductId(productId);
        Integer residue = storage.getResidue();
        // 校验参数
        if (count == null || count <= 0) {
            return ResultData.fail(ReturnCodeEnum.RC380);
        }
        // 判断库存是否足够
        if (count > residue) {
            return ResultData.fail(ReturnCodeEnum.STORAGE_NOT_ENOUGH);
        }

        log.info("------->库存服务中扣减库存开始");
        storageMapper.decrease(productId, count);
        log.info("------->库存服务中扣减库存结束");

        return ResultData.success();
    }

}

5.4、创建主启动类

@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients
@MapperScan("com.clay.mapper")
public class SeataStorageApplication {

    public static void main(String[] args) {
        SpringApplication.run(SeataStorageApplication.class, args);
    }

}

6、创建账户工程

6.1、创建 pom.xml

账户工程的 Maven 配置内容如下：

<dependencies>
    <!--seata-common-api-->
    <dependency>
        <groupId>com.clay</groupId>
        <artifactId>seata-common-api</artifactId>
        <version>1.0-SNAPSHOT</version>
    </dependency>
    <!--Web-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <!--Actuator-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <!--OpenFeign-->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-openfeign</artifactId>
    </dependency>
    <!--LoadBalancer-->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-loadbalancer</artifactId>
    </dependency>
    <!--Nacos Discovery-->
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
    </dependency>
    <!--Nacos Config-->
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-bootstrap</artifactId>
    </dependency>
    <!--Seata-->
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
    </dependency>
    <!--MySQL数据库驱动-->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
    </dependency>
    <!--Druid-->
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid-spring-boot-starter</artifactId>
    </dependency>
    <!--MyBatis-->
    <dependency>
        <groupId>org.mybatis.spring.boot</groupId>
        <artifactId>mybatis-spring-boot-starter</artifactId>
    </dependency>
    <!--Fastjson2-->
    <dependency>
        <groupId>com.alibaba.fastjson2</groupId>
        <artifactId>fastjson2</artifactId>
    </dependency>
    <!--HuTool-->
    <dependency>
        <groupId>cn.hutool</groupId>
        <artifactId>hutool-all</artifactId>
    </dependency>
    <!--Lombok-->
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <optional>true</optional>
    </dependency>
</dependencies>

6.2、创建 application.yml

server:
  port: 8087

spring:
  application:
    name: seata-account-service

  # 注册中心
  cloud:
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848

  # 数据源
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/seata_account?characterEncoding=utf8&useSSL=false&serverTimezone=GMT%2B8&rewriteBatchedStatements=true&allowPublicKeyRetrieval=true
    username: seata
    password: seata

  # Druid 连接池
  druid:
    initial-size: 5
    min-idle: 5
    max-active: 20
    max-wait: 60000
    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
    pool-prepared-statements: true
    max-pool-prepared-statement-per-connection-size: 20
    filters: stat,wall,log4j
    connection-properties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000

# MyBatis
mybatis:
  mapper-locations: classpath*:mybatis/mapper/*.xml
  type-aliases-package: com.clay.entities
  configuration:
    map-underscore-to-camel-case: true

# Seata
seata:
  # 指定从 Nacos 注册中心获取 Seata Server（TC）的地址
  registry:
    type: nacos
    nacos:
      application: seata-server # Seata Server（TC）的服务名称
      server-addr: 127.0.0.1:8848
      namespace:
      group: SEATA_GROUP
      cluster: default
  # 指定从 Nacos 配置中心获取 Seata Client 的配置信息
  config:
    type: nacos
    nacos:
      server-addr: 127.0.0.1:8848
      namespace:
      group: SEATA_GROUP
      data-id: seata-client.properties
      username:
      password:
  tx-service-group: default_tx_group # 事务组，由它获得 Seata Server（TC）服务的集群名称
  service:
    vgroup-mapping:
      default_tx_group: default # 事务组与 Seata Server（TC）服务集群的映射关系
  data-source-proxy-mode: AT
  application-id: ${spring.application.name}

# 日志
logging:
  level:
    io:
      seata: info

6.3、创建业务处理类

@Service
@Slf4j
public class AccountServiceImpl implements AccountService {

    @Resource
    private AccountMapper accountMapper;

    @Override
    public ResultData decrease(Long userId, BigDecimal money) {
        Account account = accountMapper.selectByUserId(userId);
        BigDecimal residue = account.getResidue();
        // 校验参数
        if (money == null || money.compareTo(BigDecimal.ZERO) < 1) {
            return ResultData.fail(ReturnCodeEnum.RC380);
        }
        // 判断余额是否足够
        if (money.compareTo(residue) == 1) {
            return ResultData.fail(ReturnCodeEnum.ACCOUNT_NOT_ENOUGH);
        }

        log.info("------->账户服务中扣减账户余额开始");
        accountMapper.decrease(userId, money);

        // 模拟超时异常，全局事务回滚
        myTimeOut();

        log.info("------->账户服务中扣减账户余额结束");

        return ResultData.success();
    }

    /**
     * 模拟超时异常，全局事务回滚
     *
     * <p> OpenFeign 的默认超时时间是60秒
     */
    private static void myTimeOut() {
        try {
            TimeUnit.SECONDS.sleep(65);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    /**
     * 模拟业务处理抛出异常，全局事务回滚
     */
    private static void myCompute() {
        int a = 10 / 0;
    }

}

6.4、创建主启动类

@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients
@MapperScan("com.clay.mapper")
public class SeataAccountApplication {

    public static void main(String[] args) {
        SpringApplication.run(SeataAccountApplication.class, args);
    }

}

7、案例代码测试

• 1）首先启动 MySQL Server、Nacos Server、Seata Server，并按照上文介绍的准备工作进行初始化

• 2）分别启动 seata-order-service、seata-account-service、seata-storage-service 服务

• 3）浏览器访问 http://127.0.0.1:8848/nacos 打开 Nacos 的控制台，各服务成功启动后，在 Nacos 的控制台里可以看到有多个服务已注册（如下图所示）

• 4）观察不同数据库中的 seata_account.t_account、seata_storage.t_storage 业务表的数据，如下图所示：

• 5）使用 Postman 调用订单创建接口 http://127.0.0.1:8085/order/create?userId=1&count=3&money=20&productId=1，由于账户服务有阻塞等待的耗时操作，此时通过浏览器 http://127.0.0.1:7091 访问 Seata 的控制台页面，可以看到对应的事务信息和全局锁信息，如下图所示：

• 6）由于订单服务使用 OpenFeign 远程调用账户服务来扣减账户余额时，抛出了请求超时的异常，因此订单创建接口的最终响应结果如下：

{
    "timestamp": "2024-11-09T07:15:52.746+00:00",
    "status": 500,
    "error": "Internal Server Error",
    "path": "/order/create"
}

• 7）再观察不同数据库中的 seata_account.t_account、seata_storage.t_storage 业务表的数据是否发生了变更，若数据没有变更，则说明全局事务注解 @GlobalTransactional 生效了，否则注解没有生效

• 8）创建订单的接口结束调用后，可以看到三个应用在控制台输出的日志如下：

################### seata-order 服务的日志 #####################

java.net.SocketTimeoutException: Read timed out
	at java.base/sun.nio.ch.NioSocketImpl.timedRead(NioSocketImpl.java:283) ~[na:na]
	at java.base/sun.nio.ch.NioSocketImpl.implRead(NioSocketImpl.java:309) ~[na:na]
	at java.base/sun.nio.ch.NioSocketImpl.read(NioSocketImpl.java:350) ~[na:na]
	at java.base/sun.nio.ch.NioSocketImpl$1.read(NioSocketImpl.java:803) ~[na:na]
	at java.base/java.net.Socket$SocketInputStream.read(Socket.java:966) ~[na:na]
	at java.base/java.io.BufferedInputStream.fill(BufferedInputStream.java:244) ~[na:na]

################### seata-storage 服务的日志 #####################

[seata-storage-service] [nio-8086-exec-1] c.clay.service.impl.StorageServiceImpl   : ------->库存服务中扣减库存开始
[seata-storage-service] [nio-8086-exec-1] o.a.seata.rm.AbstractResourceManager     : branch register success, xid:127.0.0.1:8091:18598824581371085, branchId:18598824581371091, lockKeys:t_storage:1
[seata-storage-service] [nio-8086-exec-1] ServiceLoader$InnerEnhancedServiceLoader : Load [org.apache.seata.rm.datasource.undo.parser.ProtostuffUndoLogParser] class fail: io/protostuff/runtime/IdStrategy
[seata-storage-service] [nio-8086-exec-1] ServiceLoader$InnerEnhancedServiceLoader : Load compatible class io.seata.rm.datasource.undo.parser.spi.JacksonSerializer
[seata-storage-service] [nio-8086-exec-1] c.clay.service.impl.StorageServiceImpl   : ------->库存服务中扣减库存结束
[seata-storage-service] [_RMROLE_1_1_144] o.a.s.c.r.p.c.RmBranchRollbackProcessor  : rm handle branch rollback process:BranchRollbackRequest{xid='127.0.0.1:8091:18598824581371085', branchId=18598824581371091, branchType=AT, resourceId='jdbc:mysql://127.0.0.1:3306/seata_storage', applicationData='null'}
[seata-storage-service] [_RMROLE_1_1_144] org.apache.seata.rm.AbstractRMHandler    : Branch Rollbacking: 127.0.0.1:8091:18598824581371085 18598824581371091 jdbc:mysql://127.0.0.1:3306/seata_storage
[seata-storage-service] [_RMROLE_1_1_144] o.a.s.r.d.undo.AbstractUndoLogManager    : xid 127.0.0.1:8091:18598824581371085 branch 18598824581371091, undo_log deleted with GlobalFinished
[seata-storage-service] [_RMROLE_1_1_144] o.a.s.rm.datasource.DataSourceManager    : branch rollback success, xid:127.0.0.1:8091:18598824581371085, branchId:18598824581371091
[seata-storage-service] [_RMROLE_1_1_144] org.apache.seata.rm.AbstractRMHandler    : Branch Rollbacked result: PhaseTwo_Rollbacked

################### seata-account 服务的日志 #####################

[seata-account-service] [nio-8087-exec-1] c.clay.service.impl.AccountServiceImpl   : ------->账户服务中扣减账户余额开始
[seata-account-service] [nio-8087-exec-1] o.a.seata.rm.AbstractResourceManager     : branch register success, xid:127.0.0.1:8091:18598824581371085, branchId:18598824581371094, lockKeys:t_account:1
[seata-account-service] [nio-8087-exec-1] ServiceLoader$InnerEnhancedServiceLoader : Load [org.apache.seata.rm.datasource.undo.parser.ProtostuffUndoLogParser] class fail: io/protostuff/runtime/IdStrategy
[seata-account-service] [nio-8087-exec-1] ServiceLoader$InnerEnhancedServiceLoader : Load compatible class io.seata.rm.datasource.undo.parser.spi.JacksonSerializer
[seata-account-service] [_RMROLE_1_1_144] o.a.s.c.r.p.c.RmBranchRollbackProcessor  : rm handle branch rollback process:BranchRollbackRequest{xid='127.0.0.1:8091:18598824581371085', branchId=18598824581371094, branchType=AT, resourceId='jdbc:mysql://127.0.0.1:3306/seata_account', applicationData='null'}
[seata-account-service] [_RMROLE_1_1_144] org.apache.seata.rm.AbstractRMHandler    : Branch Rollbacking: 127.0.0.1:8091:18598824581371085 18598824581371094 jdbc:mysql://127.0.0.1:3306/seata_account
[seata-account-service] [_RMROLE_1_1_144] o.a.s.r.d.undo.AbstractUndoLogManager    : xid 127.0.0.1:8091:18598824581371085 branch 18598824581371094, undo_log deleted with GlobalFinished
[seata-account-service] [_RMROLE_1_1_144] o.a.s.rm.datasource.DataSourceManager    : branch rollback success, xid:127.0.0.1:8091:18598824581371085, branchId:18598824581371094
[seata-account-service] [_RMROLE_1_1_144] org.apache.seata.rm.AbstractRMHandler    : Branch Rollbacked result: PhaseTwo_Rollbacked
[seata-account-service] [nio-8087-exec-1] c.clay.service.impl.AccountServiceImpl   : ------->账户服务中扣减账户余额结束

参考资料

• Seata Client 的配置问题