• SpringCloud - Spring Cloud Alibaba 之 Seata分布式事务服务；Seata TC Server集群部署（二十二）

    阅读本文前可先参考：

    SpringCloud - Spring Cloud Alibaba 之 Seata分布式事务服务详解；部署（十八）_MinggeQingchun的博客-CSDN博客

    SpringCloud - Spring Cloud Alibaba 之 Seata分布式事务服务；集成Nacos配置中心（十九）_MinggeQingchun的博客-CSDN博客

    SpringCloud - Spring Cloud Alibaba 之 Seata分布式事务服务；AT事务模式（二十）_MinggeQingchun的博客-CSDN博客

    https://blog.csdn.net/MinggeQingchun/article/details/126199942

    Seata TC Server集群部署

    生产环境下，我们需要部署集群 Seata TC Server，实现高可用。

    集群时，多个 Seata TC Server 通过 db 数据库或者redis实现全局事务会话信息的共享

    每个Seata TC Server注册自己到注册中心上，应用从注册中心获得Seata TC Server实例

    Seata TC Server 集群搭建具体步骤（采用Nacos注册中心）：

    1、下载并解压两份 seata-server-1.4.2.tar.gz

    2、初始化 Seata TC Server 的 db 数据库，在 MySQL 中，创建 seata 数据库，并在该库下执行如下SQL脚本：

    通过Seata官网下载1.4.2版本的 source 

    下载中心

    使用seata-1.4.2\script\server\db脚本（MySQL）

    1. -- -------------------------------- The script used when storeMode is 'db' --------------------------------
    2. -- the table to store GlobalSession data
    3. CREATE TABLE IF NOT EXISTS `global_table`
    4. (
    5.     `xid`                       VARCHAR(128) NOT NULL,
    6.     `transaction_id`            BIGINT,
    7.     `status`                    TINYINT      NOT NULL,
    8.     `application_id`            VARCHAR(32),
    9.     `transaction_service_group` VARCHAR(32),
    10.     `transaction_name`          VARCHAR(128),
    11.     `timeout`                   INT,
    12.     `begin_time`                BIGINT,
    13.     `application_data`          VARCHAR(2000),
    14.     `gmt_create`                DATETIME,
    15.     `gmt_modified`              DATETIME,
    16.     PRIMARY KEY (`xid`),
    17.     KEY `idx_gmt_modified_status` (`gmt_modified`, `status`),
    18.     KEY `idx_transaction_id` (`transaction_id`)
    19. ) ENGINE = InnoDB
    20.   DEFAULT CHARSET = utf8;
    21.  
    22. -- the table to store BranchSession data
    23. CREATE TABLE IF NOT EXISTS `branch_table`
    24. (
    25.     `branch_id`         BIGINT       NOT NULL,
    26.     `xid`               VARCHAR(128) NOT NULL,
    27.     `transaction_id`    BIGINT,
    28.     `resource_group_id` VARCHAR(32),
    29.     `resource_id`       VARCHAR(256),
    30.     `branch_type`       VARCHAR(8),
    31.     `status`            TINYINT,
    32.     `client_id`         VARCHAR(64),
    33.     `application_data`  VARCHAR(2000),
    34.     `gmt_create`        DATETIME(6),
    35.     `gmt_modified`      DATETIME(6),
    36.     PRIMARY KEY (`branch_id`),
    37.     KEY `idx_xid` (`xid`)
    38. ) ENGINE = InnoDB
    39.   DEFAULT CHARSET = utf8;
    40.  
    41. -- the table to store lock data
    42. CREATE TABLE IF NOT EXISTS `lock_table`
    43. (
    44.     `row_key`        VARCHAR(128) NOT NULL,
    45.     `xid`            VARCHAR(128),
    46.     `transaction_id` BIGINT,
    47.     `branch_id`      BIGINT       NOT NULL,
    48.     `resource_id`    VARCHAR(256),
    49.     `table_name`     VARCHAR(32),
    50.     `pk`             VARCHAR(36),
    51.     `gmt_create`     DATETIME,
    52.     `gmt_modified`   DATETIME,
    53.     PRIMARY KEY (`row_key`),
    54.     KEY `idx_branch_id` (`branch_id`)
    55. ) ENGINE = InnoDB
    56.   DEFAULT CHARSET = utf8;

    3、修改 seata/conf/file.conf 配置文件，修改使用 db 数据库，实现 Seata TC Server 的全局事务会话信息的共享；

    （1）mode = "db"

    （2）数据库的连接信息

    driverClassName = "com.mysql.cj.jdbc.Driver"

    url = "jdbc:mysql://IP:3306/seata"

    user = "root"

    password = "123456"

    4、设置使用 Nacos 注册中心；

    修改 seata/conf/registry.conf 配置文件，设置使用 Nacos 注册中心；

    （1）type = "nacos"

    （2）Nacos连接信息：

      nacos {
        application = "seata-server"
        serverAddr = "127.0.0.1:8848"
        group = "SEATA_GROUP"
        namespace = ""
        cluster = "default"
        username = "nacos"
        password = "nacos"
      }

    5、启动MySQL数据库和Nacos注册中心

    6、启动两个 TC Server

    执行 ./seata-server.sh -p 18091 -n 1 命令，启动第一个TC Server;

    -p：Seata TC Server 监听的端口；

    -n：Server node，在多个 TC Server 时，需区分各自节点，用于生成不同区间的 transactionId 事务编号，以免冲突；

    执行 ./seata-server.sh -p 28091 -n 2 命令，启动第二个TC Server

    注：

    如果使用虚拟机，最好修改内存为256MB

    7、打开Nacos注册中心控制台，可以看到有两个Seata TC Server 实例

      

    8、应用测试

    一、AT事务模式：单体应用SpringBoot多数据源分布式事务

    在Spring Boot单体项目中，使用了多数据源，就要保证多个数据源的数据一致性，即产生了分布式事务的问题，采用Seata的AT事务模式来解决该分布式事务问题

    以下图购物下单为例

    1、创建数据库、表、插入数据等

    （1）accountdb账户库、account账户表

    1. SET NAMES utf8mb4;
    2. SET FOREIGN_KEY_CHECKS = 0;
    3.  
    4. -- ----------------------------
    5. -- Table structure for account
    6. -- ----------------------------
    7. DROP TABLE IF EXISTS `account`;
    8. CREATE TABLE `account`  (
    9.   `id` int(20) NOT NULL AUTO_INCREMENT,
    10.   `user_id` int(20) NULL DEFAULT NULL,
    11.   `balance` decimal(20, 0) NULL DEFAULT NULL,
    12.   `update_time` datetime(6) NULL DEFAULT NULL,
    13.   PRIMARY KEY (`id`) USING BTREE
    14. ) ENGINE = InnoDB AUTO_INCREMENT = 2 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;
    15.  
    16. SET FOREIGN_KEY_CHECKS = 1;

    （2）productdb产品库、product产品表

    1. SET NAMES utf8mb4;
    2. SET FOREIGN_KEY_CHECKS = 0;
    3.  
    4. -- ----------------------------
    5. -- Table structure for product
    6. -- ----------------------------
    7. DROP TABLE IF EXISTS `product`;
    8. CREATE TABLE `product`  (
    9.   `id` int(20) NOT NULL AUTO_INCREMENT,
    10.   `name` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
    11.   `price` decimal(10, 2) NULL DEFAULT NULL,
    12.   `stock` varchar(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,
    13.   `add_time` datetime(6) NULL DEFAULT NULL,
    14.   `update_time` datetime(6) NULL DEFAULT NULL,
    15.   PRIMARY KEY (`id`) USING BTREE
    16. ) ENGINE = InnoDB AUTO_INCREMENT = 2 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;
    17.  
    18. SET FOREIGN_KEY_CHECKS = 1;

    （3）orderdb订单库、orders 订单表

    1. SET NAMES utf8mb4;
    2. SET FOREIGN_KEY_CHECKS = 0;
    3.  
    4. -- ----------------------------
    5. -- Table structure for orders
    6. -- ----------------------------
    7. DROP TABLE IF EXISTS `orders`;
    8. CREATE TABLE `orders`  (
    9.   `id` int(20) NOT NULL AUTO_INCREMENT,
    10.   `user_id` int(20) NULL DEFAULT NULL,
    11.   `product_id` int(20) NULL DEFAULT NULL,
    12.   `pay_amount` decimal(20, 0) NULL DEFAULT NULL,
    13.   `add_time` datetime(6) NULL DEFAULT NULL,
    14.   `update_time` datetime(6) NULL DEFAULT NULL,
    15.   PRIMARY KEY (`id`) USING BTREE
    16. ) ENGINE = InnoDB AUTO_INCREMENT = 6 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Dynamic;
    17.  
    18. SET FOREIGN_KEY_CHECKS = 1;

    （4）undo_log表 

    Seata AT 模式

    1. -- 注意此处0.7.0+ 增加字段 context
    2. CREATE TABLE `undo_log` (
    3.   `id` bigint(20) NOT NULL AUTO_INCREMENT,
    4.   `branch_id` bigint(20) NOT NULL,
    5.   `xid` varchar(100) NOT NULL,
    6.   `context` varchar(128) NOT NULL,
    7.   `rollback_info` longblob NOT NULL,
    8.   `log_status` int(11) NOT NULL,
    9.   `log_created` datetime NOT NULL,
    10.   `log_modified` datetime NOT NULL,
    11.   PRIMARY KEY (`id`),
    12.   UNIQUE KEY `ux_undo_log` (`xid`,`branch_id`)
    13. ) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

    注：

    每个库必须创建 undo_log 表，是 Seata AT模式必须创建的表，主要用于分支事务的回滚

    Seata AT 模式

      

    2、创建 SpringBoot单体应用

    1、创建一个 springboot应用，命名 springcloud-alibaba-2-seata-distributed-transaction

    2、添加依赖（非Spring CLoud 微服务项目，没有Spring CLoud依赖）

    主要添加 Nacos-client依赖

    2.         <dependency>
    3.             <groupId>com.alibaba.nacosgroupId>
    4.             <artifactId>nacos-clientartifactId>
    5.             <version>2.1.0version>
    6.         dependency>
    1. <groupId>com.companygroupId>
    2.     <artifactId>springcloud-alibaba-2-seata-distributed-transactionartifactId>
    3.     <version>1.0.0version>
    4.  
    5.     <name>springcloud-alibaba-2-seata-distributed-transactionname>
    6.     <description>Demo project for Spring Bootdescription>
    7.  
    8.     <properties>
    9.         <java.version>1.8java.version>
    10.         <project.build.sourceEncoding>UTF-8project.build.sourceEncoding>
    11.         <project.reporting.outputEncoding>UTF-8project.reporting.outputEncoding>
    12.         <spring-boot.version>2.3.12.RELEASEspring-boot.version>
    13.         <spring-cloud-alibaba.version>2.2.7.RELEASEspring-cloud-alibaba.version>
    14.     properties>
    15.  
    16.     <dependencies>
    17.         <dependency>
    18.             <groupId>org.springframework.bootgroupId>
    19.             <artifactId>spring-boot-starter-webartifactId>
    20.         dependency>
    21.  
    22.         <dependency>
    23.             <groupId>org.springframework.bootgroupId>
    24.             <artifactId>spring-boot-starter-actuatorartifactId>
    25.         dependency>
    26.  
    27.         <dependency>
    28.             <groupId>org.springframework.bootgroupId>
    29.             <artifactId>spring-boot-starter-testartifactId>
    30.             <scope>testscope>
    31.             <exclusions>
    32.                 <exclusion>
    33.                     <groupId>org.junit.vintagegroupId>
    34.                     <artifactId>junit-vintage-engineartifactId>
    35.                 exclusion>
    36.             exclusions>
    37.         dependency>
    38.  
    39.         <dependency>
    40.             <groupId>org.projectlombokgroupId>
    41.             <artifactId>lombokartifactId>
    42.         dependency>
    43.  
    44.         
    45.         <dependency>
    46.             <groupId>mysqlgroupId>
    47.             <artifactId>mysql-connector-javaartifactId>
    49.         dependency>
    50.  
    51.         
    52.         <dependency>
    53.             <groupId>org.mybatis.spring.bootgroupId>
    54.             <artifactId>mybatis-spring-boot-starterartifactId>
    55.             <version>2.1.3version>
    56.         dependency>
    57.  
    58.         
    59.         <dependency>
    60.             <groupId>io.seatagroupId>
    61.             <artifactId>seata-spring-boot-starterartifactId>
    62.             <version>1.3.0version>
    63.         dependency>
    64.  
    65.         
    66.         <dependency>
    67.             <groupId>com.baomidougroupId>
    68.             <artifactId>dynamic-datasource-spring-boot-starterartifactId>
    69.             <version>3.2.0version>
    70.         dependency>
    71.  
    72.         
    73.         <dependency>
    74.             <groupId>com.alibaba.nacosgroupId>
    75.             <artifactId>nacos-clientartifactId>
    76.             <version>2.1.0version>
    77.         dependency>
    78.     dependencies>
    79.  
    80.     
    81.     <dependencyManagement>
    82.         <dependencies>
    83.             <dependency>
    84.                 <groupId>com.alibaba.cloudgroupId>
    85.                 <artifactId>spring-cloud-alibaba-dependenciesartifactId>
    86.                 <version>${spring-cloud-alibaba.version}version>
    87.                 <type>pomtype>
    88.                 <scope>importscope>
    89.             dependency>
    90.             
    91.             <dependency>
    92.                 <groupId>org.springframework.cloudgroupId>
    93.                 <artifactId>spring-cloud-dependenciesartifactId>
    94.                 <version>Hoxton.SR12version>
    95.                 <type>pomtype>
    96.                 <scope>importscope>
    97.             dependency>
    98.             <dependency>
    99.                 <groupId>org.springframework.bootgroupId>
    100.                 <artifactId>spring-boot-dependenciesartifactId>
    101.                 <version>${spring-boot.version}version>
    102.                 <type>pomtype>
    103.                 <scope>importscope>
    104.             dependency>
    105.         dependencies>
    106.     dependencyManagement>
    107.  
    108.     <build>
    109.         <plugins>
    110.             <plugin>
    111.                 <groupId>org.apache.maven.pluginsgroupId>
    112.                 <artifactId>maven-compiler-pluginartifactId>
    113.                 <configuration>
    114.                     <source>1.8source>
    115.                     <target>1.8target>
    116.                     <encoding>UTF-8encoding>
    117.                 configuration>
    118.             plugin>
    119.             <plugin>
    120.                 <groupId>org.springframework.bootgroupId>
    121.                 <artifactId>spring-boot-maven-pluginartifactId>
    122.             plugin>
    123.             
    124.             <plugin>
    125.                 <groupId>org.mybatis.generatorgroupId>
    126.                 <artifactId>mybatis-generator-maven-pluginartifactId>
    127.                 <version>1.4.0version>
    128.                 <configuration>
    129.                     
    130.                     <configurationFile>src/main/resources/generatorConfig.xmlconfigurationFile>
    131.                     
    132.                     <verbose>trueverbose>
    133.                     
    134.                     <overwrite>trueoverwrite>
    135.                 configuration>
    136.             plugin>
    137.         plugins>
    138.  
    139.         <resources>
    140.             <resource>
    141.                 <directory>src/main/javadirectory>
    142.                 <includes>
    143.                     <include>**/*.xmlinclude>
    144.                 includes>
    145.             resource>
    146.             <resource>
    147.                 <directory>src/main/resourcesdirectory>
    148.                 <includes>
    149.                     <include>**/*.*include>
    150.                 includes>
    151.             resource>
    152.         resources>
    153.     build>

    3、application.properties配置文件

    1. #内嵌服务器端口
    2. server.port=8081
    3.  
    4. #应用服务名称
    5. spring.application.name=springcloud-alibaba-2-seata-distributed-transaction
    6.  
    7. # 设置默认的数据源或者数据源组，默认值即为master
    8. spring.datasource.dynamic.primary=order-ds
    9.  
    10. # 订单order数据源配置
    11. spring.datasource.dynamic.datasource.order-ds.url=jdbc:mysql://localhost:3306/orderdb?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8&rewriteBatchedStatements=true&useSSL=false
    12. spring.datasource.dynamic.datasource.order-ds.driver-class-name=com.mysql.cj.jdbc.Driver
    13. spring.datasource.dynamic.datasource.order-ds.username=root
    14. spring.datasource.dynamic.datasource.order-ds.password=admin123456
    15.  
    16. # 商品product数据源配置
    17. spring.datasource.dynamic.datasource.product-ds.url=jdbc:mysql://localhost:3306/productdb?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8&rewriteBatchedStatements=true&useSSL=false
    18. spring.datasource.dynamic.datasource.product-ds.driver-class-name=com.mysql.cj.jdbc.Driver
    19. spring.datasource.dynamic.datasource.product-ds.username=root
    20. spring.datasource.dynamic.datasource.product-ds.password=admin123456
    21.  
    22. # 账户account数据源配置
    23. spring.datasource.dynamic.datasource.account-ds.url=jdbc:mysql://localhost:3306/accountdb?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8&rewriteBatchedStatements=true&useSSL=false
    24. spring.datasource.dynamic.datasource.account-ds.driver-class-name=com.mysql.cj.jdbc.Driver
    25. spring.datasource.dynamic.datasource.account-ds.username=root
    26. spring.datasource.dynamic.datasource.account-ds.password=admin123456
    27.  
    28. # 是否启动对Seata的集成
    29. spring.datasource.dynamic.seata=true
    30.  
    31.  
    32. #-----------------------------------------------------------
    33. ##单机版 tc server 配置
    34. ## Seata应用编号，默认为 ${spring.application.name}
    35. #seata.application-id=springboot-seata
    36. ## Seata事务组编号，用于TC集群名，一般格式为：${spring.application.name}-group
    37. #seata.tx-service-group=springboot-seata-group
    38. ## 虚拟组和分组的映射 seata.service.vgroup-mapping.${seata.tx-service-group}=default
    39. #seata.service.vgroup-mapping.springboot-seata-group=default
    40. ## 分组和Seata服务的映射，此处default指上面 seata.service.vgroup-mapping.springboot-seata-group 的值 default
    41. #seata.service.grouplist.default=192.168.133.129:8091
    42. ## 存储模式 默认 file模式
    43. #seata.config.type=file
    44. ## 默认为 file
    45. #seata.registry.type=file
    46. #------------------------------------------------------------
    47.  
    48.  
    49. #------------------------------------------------------------
    50. #集群版 tc server 配置
    51. # Seata应用编号，默认为 ${spring.application.name}
    52. seata.application-id=springboot-seata
    53. # Seata事务组编号，用于TC集群名，一般格式为：${spring.application.name}-group
    54. seata.tx-service-group=springboot-seata-group
    55. # 虚拟组和分组的映射 seata.service.vgroup-mapping.${seata.tx-service-group}=default
    56. seata.service.vgroup-mapping.springboot-seata-group=default
    57. #------------------------------------------------------------
    58.  
    59. #设置使用注册中心
    60. seata.registry.type=nacos
    61. seata.registry.nacos.cluster=default
    62. seata.registry.nacos.application=seata-server
    63. seata.registry.nacos.group=SEATA_GROUP
    64. seata.registry.nacos.server-addr=192.168.133.129:8848
    65.  
    66. seata.enable-auto-data-source-proxy=false
    67. seata.client.rm.lock.retry-policy-branch-rollback-on-conflict=false

    4、编写相应的 controller、model、mapper、service类，这里只给出调用顺序相关的类

     controller测试类

    1. @Slf4j //lombok
    2. @RestController
    3. public class OrderController {
    4.  
    5.     @Autowired
    6.     private OrderService orderService;
    7.  
    8.     @RequestMapping("/order")
    9.     public Integer createOrder(@RequestParam("userId") Integer userId,
    10.                                @RequestParam("productId") Integer productId) throws Exception {
    11.  
    12.         log.info("请求下单, 用户:{}, 商品:{}", userId, productId);
    13.  
    14.         return orderService.createOrder(userId, productId);
    15.     }
    16. }

    order逻辑类

    注：

    （1）@DS注解；多数据源切换

    （2）@GlobalTransactional注解；seata全局事务注解

    主服务加上@GlobalTransactional注解即可，被调用服务不用加@GlobalTransactional和@Transactional

    1. @Slf4j
    2. @Service
    3. public class OrderServiceImpl implements OrderService {
    4.  
    5.     @Autowired
    6.     private OrdersMapper ordersMapper;
    7.  
    8.     @Autowired
    9.     private AccountService accountService;
    10.  
    11.     @Autowired
    12.     private ProductService productService;
    13.  
    14.     @Override
    15.     /**
    16.      * MyBatis-Plus 使用 @DS注解 做多数据源切换
    17.      * 语法：@DS(value = "数据源名称")
    18.      * 1、依赖：
    19.      *         
    20.      *             com.baomidou
    21.      *             dynamic-datasource-spring-boot-starter
    22.      *             3.0.0
    23.      *         
    24.      * 2、yml 或 properties 配置
    25.      * # 设置默认的数据源或者数据源组，默认值即为master
    26.      * spring.datasource.dynamic.primary=order-ds
    27.      *
    28.      * # 订单order数据源配置
    29.      * spring.datasource.dynamic.datasource.order-ds.url=jdbc:mysql://localhost:3306/orderdb?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8&rewriteBatchedStatements=true&useSSL=false
    30.      * spring.datasource.dynamic.datasource.order-ds.driver-class-name=com.mysql.cj.jdbc.Driver
    31.      * spring.datasource.dynamic.datasource.order-ds.username=root
    32.      * spring.datasource.dynamic.datasource.order-ds.password=admin123456
    33.      *
    34.      * # 商品product数据源配置
    35.      * spring.datasource.dynamic.datasource.product-ds.url=jdbc:mysql://localhost:3306/productdb?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8&rewriteBatchedStatements=true&useSSL=false
    36.      * spring.datasource.dynamic.datasource.product-ds.driver-class-name=com.mysql.cj.jdbc.Driver
    37.      * spring.datasource.dynamic.datasource.product-ds.username=root
    38.      * spring.datasource.dynamic.datasource.product-ds.password=admin123456
    39.      * 3、@DS注解到实现类或者实现类的方法上才可以
    40.      * 当注解添加到类上，意味着此类里的方法都使用此数据源；
    41.      * 当注解添加到方法上时，意味着此方法上使用的数据源优先级高于其他一切配置
    42.      * 注：
    43.      * （1）注解添加在dao.mapper上无效
    44.      * （2）注解添加到interface Service类上无效
    45.      * （3）注解添加到interface Service方法上无效
    46.      */
    47.     @DS(value = "order-ds")
    48.     @GlobalTransactional //seata全局事务注解
    49.     public Integer createOrder(Integer userId, Integer productId) throws Exception {
    50.         Integer amount = 1; // 购买数量暂时设置为 1
    51.  
    52.         log.info("当前 XID: {}", RootContext.getXID());
    53.  
    54.         //1、减库存
    55.         Product product = productService.reduceStock(productId, amount);
    56.  
    57.         //2、减余额
    58.         accountService.reduceBalance(userId, product.getPrice());
    59.  
    60.         //3、下订单
    61.         Orders order = new Orders();
    62.         order.setUserId(userId);
    63.         order.setProductId(productId);
    64.         order.setPayAmount(product.getPrice().multiply(new BigDecimal(amount)));
    65.         order.setAddTime(new Date());
    66.         ordersMapper.insertSelective(order);
    67.  
    68.         //造成异常，测试是否回滚
    69.         //int a = 10/0;
    70.  
    71.         log.info("下订单: {}", order.getId());
    72.  
    73.         // 返回订单编号
    74.         return order.getId();
    75.     }
    76. }
    77.  
    78.  product逻辑类

     product逻辑类

    1. @Slf4j
    2. @Service
    3. public class ProductServiceImpl implements ProductService {
    4.  
    5.     @Autowired
    6.     private ProductMapper productMapper;
    7.  
    8.     @Override
    9.     @DS(value = "product-ds")
    10.     public Product reduceStock(Integer productId, Integer amount) throws Exception {
    11.         log.info("当前 XID: {}", RootContext.getXID());
    12.  
    13.         // 检查库存
    14.         Product product = productMapper.selectByPrimaryKey(productId);
    15.         if (product.getStock() < amount) {
    16.             throw new Exception("库存不足");
    17.         }
    18.  
    19.         // 扣减库存
    20.         int updateCount = productMapper.reduceStock(productId, amount);
    21.         // 扣除成功
    22.         if (updateCount == 0) {
    23.             throw new Exception("库存不足");
    24.         }
    25.  
    26.         //造成异常，测试是否回滚
    27.         //int a = 10/0;
    28.  
    29.         // 扣除成功
    30.         log.info("扣除 {} 库存成功", productId);
    31.  
    32.         return product;
    33.     }
    34. }

    account逻辑类

    1. @Slf4j
    2. @Service
    3. public class AccountServiceImpl implements AccountService {
    4.  
    5.     @Autowired
    6.     private AccountMapper accountMapper;
    7.  
    8.     @Override
    9.     @DS(value = "account-ds")
    10.     public void reduceBalance(Integer userId, BigDecimal money) throws Exception {
    11.         log.info("当前 XID: {}", RootContext.getXID());
    12.  
    13.         // 检查余额
    14.         Account account = accountMapper.selectAccountByUserId(userId);
    15.         if (account.getBalance().doubleValue() < money.doubleValue()) {
    16.             throw new Exception("余额不足");
    17.         }
    18.  
    19.         // 扣除余额
    20.         int updateCount = accountMapper.reduceBalance(userId, money);
    21.         // 扣除成功
    22.         if (updateCount == 0) {
    23.             throw new Exception("余额不足");
    24.         }
    25.  
    26.         //造成异常，测试是否回滚
    27.         //int a = 10/0;
    28.  
    29.         log.info("扣除用户 {} 余额成功", userId);
    30.     }
    31. }

    5、启动seata-server；浏览器输入访问 http://localhost:8081/order?userId=1&productId=1

    可分别在 OrderServiceImpl、ProductServiceImpl、AccountServiceImpl 实现类中 写入如下代码进行事务回滚测试

    1. //造成异常，测试是否回滚
    2. int a = 10/0;

    二、AT事务模式：微服务SpringCloud的分布式事务

    1、创建 4 个SpringBoot 模块

    （1）springcloud-alibaba-2-seata-distributed-commons

    1. <dependencies>
    2.         
    3.         <dependency>
    4.             <groupId>org.projectlombokgroupId>
    5.             <artifactId>lombokartifactId>
    6.             <version>1.18.16version>
    7.         dependency>
    8.  
    9.         
    10.         <dependency>
    11.             <groupId>org.springframework.cloudgroupId>
    12.             <artifactId>spring-cloud-starter-openfeignartifactId>
    13.             <version>3.0.0version>
    14.         dependency>
    15.     dependencies>
    1. @FeignClient(name = "springcloud-alibaba-2-seata-distributed-account")
    2. public interface FeignAccountService {
    3.  
    4.     /**
    5.      * 扣除余额
    6.      *
    7.      * @param userId 用户ID
    8.      * @param money  扣减金额
    9.      * @throws Exception 失败时抛出异常
    10.      */
    11.     @PostMapping("/account/reduceBalance")
    12.     void reduceBalance(@RequestParam("userId") Integer userId, @RequestParam("money") BigDecimal money);
    13. }
    14.  
    15.  
    16. @FeignClient(name = "springcloud-alibaba-2-seata-distributed-order")
    17. public interface FeignOrderService {
    18.  
    19.     /**
    20.      * 创建订单
    21.      *
    22.      * @param userId 用户ID
    23.      * @param productId 产品ID
    24.      * @return 订单编号
    25.      * @throws Exception 创建订单失败，抛出异常
    26.      */
    27.     Integer createOrder(Integer userId, Integer productId) throws Exception;
    28.  
    29. }
    30.  
    31. @FeignClient(name = "springcloud-alibaba-2-seata-distributed-product")
    32. public interface FeignProductService {
    33.  
    34.     /**
    35.      * 减库存
    36.      *
    37.      * @param productId 商品ID
    38.      * @param amount    扣减数量
    39.      * @throws Exception 扣减失败时抛出异常
    40.      */
    41.     @PostMapping("/product/reduceStock")
    42.     Product reduceStock(@RequestParam("productId") Integer productId, @RequestParam("amount") Integer amount);
    43. }

    （2）springcloud-alibaba-2-seata-distributed-order 

    注意：

    1、异常需要层层往上抛，如果你在子服务将异常处理的话（比如全局异常处理GlobalExceptionHandler），seata会认为你已经手动处理了异常

    2、出现事务失效的情况下，优先检查 RootContext.getXID() ，xid是否传递且一致

    3、主服务加上@GlobalTransactional注解即可，被调用服务不用加@GlobalTransactional和@Transactional

    4、@GlobalTransactional(rollbackFor = Exception.class)最好加上rollbackFor = Exception.class，表示遇到Exception都回滚，不然遇到有些异常（如自定义异常）则不会回滚

    依赖注意如下：

    （1）本身有 spring-cloud-starter-alibaba-nacos-discovery 依赖，不再需要额外添加 nacos-client 依赖

    （2）spring-cloud-starter-alibaba-seata 包含 seata-spring-boot-starter 依赖，但是有些配置有问题，需要自己导入和Seata Server 版本相同的依赖

    2.         <dependency>
    3.             <groupId>com.alibaba.cloudgroupId>
    4.             <artifactId>spring-cloud-starter-alibaba-seataartifactId>
    5.             <exclusions>
    6.                 <exclusion>
    7.                     <groupId>io.seatagroupId>
    8.                     <artifactId>seata-spring-boot-starterartifactId>
    9.                 exclusion>
    10.             exclusions>
    11.         dependency>
    12.  
    13.         
    14.         <dependency>
    15.             <groupId>io.seatagroupId>
    16.             <artifactId>seata-spring-boot-starterartifactId>
    17.             <version>1.4.2version>
    18.         dependency>
    1. <groupId>com.companygroupId>
    2.     <artifactId>springcloud-alibaba-2-seata-distributed-orderartifactId>
    3.     <version>1.0.0version>
    4.  
    5.     <name>springcloud-alibaba-2-seata-distributed-ordername>
    6.     <description>Demo project for Spring Bootdescription>
    7.  
    8.     <properties>
    9.         <java.version>1.8java.version>
    10.         <project.build.sourceEncoding>UTF-8project.build.sourceEncoding>
    11.         <project.reporting.outputEncoding>UTF-8project.reporting.outputEncoding>
    12.         <spring-boot.version>2.3.12.RELEASEspring-boot.version>
    13.         <spring-cloud-alibaba.version>2.2.7.RELEASEspring-cloud-alibaba.version>
    14.     properties>
    15.  
    16.     <dependencies>
    17.         <dependency>
    18.             <groupId>org.springframework.bootgroupId>
    19.             <artifactId>spring-boot-starter-webartifactId>
    20.         dependency>
    21.  
    22.         
    23.         <dependency>
    24.             <groupId>com.alibaba.cloudgroupId>
    25.             <artifactId>spring-cloud-starter-alibaba-nacos-discoveryartifactId>
    26.         dependency>
    27.  
    28.         <dependency>
    29.             <groupId>org.springframework.bootgroupId>
    30.             <artifactId>spring-boot-starter-testartifactId>
    31.             <scope>testscope>
    32.             <exclusions>
    33.                 <exclusion>
    34.                     <groupId>org.junit.vintagegroupId>
    35.                     <artifactId>junit-vintage-engineartifactId>
    36.                 exclusion>
    37.             exclusions>
    38.         dependency>
    39.  
    40.         <dependency>
    41.             <groupId>org.projectlombokgroupId>
    42.             <artifactId>lombokartifactId>
    43.         dependency>
    44.  
    45.         
    46.         <dependency>
    47.             <groupId>mysqlgroupId>
    48.             <artifactId>mysql-connector-javaartifactId>
    49.         dependency>
    50.  
    51.         
    52.         <dependency>
    53.             <groupId>org.mybatis.spring.bootgroupId>
    54.             <artifactId>mybatis-spring-boot-starterartifactId>
    55.             <version>2.1.3version>
    56.         dependency>
    57.  
    58.         
    59.         <dependency>
    60.             <groupId>com.alibaba.cloudgroupId>
    61.             <artifactId>spring-cloud-starter-alibaba-seataartifactId>
    62.             <exclusions>
    63.                 <exclusion>
    64.                     <groupId>io.seatagroupId>
    65.                     <artifactId>seata-spring-boot-starterartifactId>
    66.                 exclusion>
    67.             exclusions>
    68.         dependency>
    69.  
    70.         
    71.         <dependency>
    72.             <groupId>io.seatagroupId>
    73.             <artifactId>seata-spring-boot-starterartifactId>
    74.             <version>1.4.2version>
    75.         dependency>
    76.  
    77.         
    78.         <dependency>
    79.             <groupId>com.companygroupId>
    80.             <artifactId>springcloud-alibaba-2-seata-distributed-commonsartifactId>
    81.             <version>1.0.0version>
    82.         dependency>
    83.  
    84.     dependencies>
    85.  
    86.     
    87.     <dependencyManagement>
    88.         <dependencies>
    89.             <dependency>
    90.                 <groupId>com.alibaba.cloudgroupId>
    91.                 <artifactId>spring-cloud-alibaba-dependenciesartifactId>
    92.                 <version>${spring-cloud-alibaba.version}version>
    93.                 <type>pomtype>
    94.                 <scope>importscope>
    95.             dependency>
    96.             
    97.             <dependency>
    98.                 <groupId>org.springframework.cloudgroupId>
    99.                 <artifactId>spring-cloud-dependenciesartifactId>
    100.                 <version>Hoxton.SR12version>
    101.                 <type>pomtype>
    102.                 <scope>importscope>
    103.             dependency>
    104.             <dependency>
    105.                 <groupId>org.springframework.bootgroupId>
    106.                 <artifactId>spring-boot-dependenciesartifactId>
    107.                 <version>${spring-boot.version}version>
    108.                 <type>pomtype>
    109.                 <scope>importscope>
    110.             dependency>
    111.         dependencies>
    112.     dependencyManagement>
    113.  
    114.     <build>
    115.         <plugins>
    116.             <plugin>
    117.                 <groupId>org.apache.maven.pluginsgroupId>
    118.                 <artifactId>maven-compiler-pluginartifactId>
    119.                 <version>3.8.1version>
    120.                 <configuration>
    121.                     <source>1.8source>
    122.                     <target>1.8target>
    123.                     <encoding>UTF-8encoding>
    124.                 configuration>
    125.             plugin>
    126.             <plugin>
    127.                 <groupId>org.springframework.bootgroupId>
    128.                 <artifactId>spring-boot-maven-pluginartifactId>
    129.             plugin>
    130.         plugins>
    131.  
    132.         <resources>
    133.             <resource>
    134.                 <directory>src/main/javadirectory>
    135.                 <includes>
    136.                     <include>**/*.xmlinclude>
    137.                 includes>
    138.             resource>
    139.             <resource>
    140.                 <directory>src/main/resourcesdirectory>
    141.                 <includes>
    142.                     <include>**/*.*include>
    143.                 includes>
    144.             resource>
    145.         resources>
    146.     build>
    1. @Slf4j //lombok
    2. @RestController
    3. public class OrderController {
    4.  
    5.     @Autowired
    6.     private OrderService orderService;
    7.  
    8.     @RequestMapping("/order")
    9.     public Integer createOrder(@RequestParam("userId") Integer userId,
    10.                                @RequestParam("productId") Integer productId) throws Exception {
    11.  
    12.         log.info("请求下单, 用户:{}, 商品:{}", userId, productId);
    13.  
    14.         return orderService.createOrder(userId, productId);
    15.     }
    16. }
    17.  
    18.  
    19. @Slf4j
    20. @Service
    21. public class OrderServiceImpl implements OrderService {
    22.  
    23.     @Autowired
    24.     private OrdersMapper ordersMapper;
    25.  
    26.     @Autowired
    27.     private FeignAccountService accountService;
    28.  
    29.     @Autowired
    30.     private FeignProductService productService;
    31.  
    32.     @Override
    33.     //seata全局事务注解；name要唯一
    34.     @GlobalTransactional//(name = "seata-order-GlobalTransactional",rollbackFor = Exception.class)
    35.     public Integer createOrder(Integer userId, Integer productId) {
    36.         Integer amount = 1; // 购买数量暂时设置为 1
    37.  
    38.         log.info("当前 XID: {}", RootContext.getXID());
    39.  
    40.         //1、减库存
    41.         Product product = productService.reduceStock(productId, amount);
    42.  
    43.         //2、减余额
    44.         accountService.reduceBalance(userId, product.getPrice());
    45.  
    46.         //3、下订单
    47.         Orders order = new Orders();
    48.         order.setUserId(userId);
    49.         order.setProductId(productId);
    50.         order.setPayAmount(product.getPrice().multiply(new BigDecimal(amount)));
    51.         order.setAddTime(new Date());
    52.         ordersMapper.insertSelective(order);
    53.  
    54.         //造成异常，测试是否回滚
    55.         int a = 10/0;
    56.  
    57.         log.info("下订单: {}", order.getId());
    58.  
    59.         // 返回订单编号
    60.         return order.getId();
    61.     }
    62. }
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  • 原文地址：https://blog.csdn.net/MinggeQingchun/article/details/126225632