SpringCloud整合seata,XA、AT、TCC、SAGA模式

参考资料：

SpringCloud-Alibaba搭建

SpringCloud-nacos整合

Seata部署

参考demo（及学习资料）

seata官网

参考视频​​​​​c（AT模式的UNDO_LOG讲的可能有点问题，但是很通俗易懂）

 参考视频2（不太通俗易懂）

沽泡付费视频（就是对着官网念） 

上述三个视频的参考资料

---

准备环境：

        该教程默认已经有如下环境，如果没有可以参考上述教程：

• 部署了Nacos
• 部署了Seata
• 搭建了SpringCloud 
• 并且版本已经做到了统一（只要保证JVM里面使用的jar包版本和部署的版本一致即可）
• 同一系列版本见Wiki

 

---

模拟事件-搭建demo：

        因为seata是分布式事务，所以这个例子需要多个微服务，多个库进行联动

创建数据库

        首先创建两个数据库

CREATE DATABASE /*!32312 IF NOT EXISTS*/`seata_db1` /*!40100 DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci */;USE `seata_db1`;/*Table structure for table `money` */DROP TABLE IF EXISTS `money`;CREATE TABLE `money` (`id` varchar(32) NOT NULL COMMENT '主键',`user_name` varchar(32) DEFAULT NULL COMMENT '名字',`bank_money` double DEFAULT NULL COMMENT '银行余额',PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;/*Data for the table `money` */insert  into `money`(`id`,`user_name`,`bank_money`) values 
('084d862fa66c4c82886a4b0bb9214ab1','张三',100);

 

CREATE DATABASE /*!32312 IF NOT EXISTS*/`seata_db2` /*!40100 DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci */;USE `seata_db2`;/*Table structure for table `order_details` */DROP TABLE IF EXISTS `order_details`;CREATE TABLE `order_details` (`id` varchar(32) NOT NULL COMMENT '主键',`goods_name` varchar(32) DEFAULT NULL COMMENT '商品名',`count` int(11) DEFAULT NULL COMMENT '仓库余额',PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;/*Data for the table `order_details` */insert  into `order_details`(`id`,`goods_name`,`count`) values 
('7072809e86834335843bc918c33074ec','desk',50);

 

 创建示例微服务

         用搭建好的SpringClud框架，默认已经整合了nacos,并且已经部署好了seata

        关于微服务的创建，这里就不再赘述了，可以参考该文章

          参考上述文章，创建两个微服务   seata-demo1和seata-demo2，然后进行相关依赖的导入

        这里是将所有的依赖加入到了公共服务里面，请根据个人情况使用，在common-service服务中的pom.xml文件，

Lombok依赖

        <dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>${lombok.version}</version></dependency>

 控制层依赖

        <!-- springboot starter web --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency>

 mybatis-plus及数据库相关

        <dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-boot-starter</artifactId><version>3.3.1.tmp</version></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-jdbc</artifactId></dependency><!--引入mysql--><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>8.0.11</version></dependency>

fegin组件

        <!--fegin组件--><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-openfeign</artifactId></dependency>

 nacos相关（使用时默认的，如果nacos不是上述系列的则需要指定版本）

        <!--引入nacos client的依赖--><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId></dependency><!--引入nacos config 依赖--><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId></dependency>

还有一些bootstrap.yml启动的辅助依赖

        <dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-bootstrap</artifactId></dependency><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-loadbalancer</artifactId></dependency>

最后添加的依赖如下：

然后将公共依赖引入创建的两个微服务，参考

        <dependency><groupId>org.example</groupId><artifactId>common-service</artifactId><version>1.0-SNAPSHOT</version></dependency>

将相关配置交给nacos管理,可以参考文章，这里只是贴代码，不赘述

• seata-demo1

bootstrap.yml

spring:profiles:include:uat

 bootstrap-uat.yml

spring:config:use-legacy-processing: trueprofiles.active: uatapplication:name: seata-demo1cloud:nacos:config:server-addr: localhost:8848group: DEFAULT_GROUPusername: nacospassword: nacosfile-extension: yamlrefresh-enabled: true

然后将相关配置放入到nacos中

server:port: 8081
spring:nacos:discovery:server-addr: localhost:8848username: nacospassword: nacosdatasource:driver-class-name: com.mysql.cj.jdbc.Driverurl: jdbc:mysql://localhost:3306/seata_db1?characterEncoding=UTF-8username: rootpassword: 123888

•  seata-demo2

bootstrap.yml

spring:profiles:include:uat

bootstrap-uat.yml

spring:config:use-legacy-processing: trueprofiles.active: uatapplication:name: seata-demo2cloud:nacos:config:server-addr: localhost:8848group: DEFAULT_GROUPusername: nacospassword: nacosfile-extension: yamlrefresh-enabled: true

 然后将相关配置放入到nacos中

server:port: 8080
spring:nacos:discovery:server-addr: localhost:8848username: nacospassword: nacosdatasource:driver-class-name: com.mysql.cj.jdbc.Driverurl: jdbc:mysql://localhost:3306/seata_db2?characterEncoding=UTF-8username: rootpassword: 123888

这样的话，就可以连接到数据库了，然后编写 mybatis-plus 的三层，参考文章，这里将不再赘述，仅仅是贴代码

• seata-demo1

package org.example.entity;import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;@Data
@TableName("money")
public class Money {@TableIdprivate String id;@TableField("user_name")private String userName;@TableField("bank_money")private Double bankMoney;
}

package org.example.dao;import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.example.entity.Money;public interface MoneyMapper extends  BaseMapper<Money> {
}

package org.example.service;import com.baomidou.mybatisplus.extension.service.IService;
import org.example.entity.Money;public interface MoneyService extends IService<Money> {}

package org.example.service;import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.springframework.stereotype.Service;
import org.example.dao.MoneyMapper;
import org.example.entity.Money;
import org.springframework.transaction.annotation.Transactional;@Service
public class MoneyServiceImpl extends ServiceImpl<MoneyMapper, Money> implements MoneyService{}

• seata-demo2

@Data
@TableName("order_details")
public class OrderDetails {@TableIdprivate String id;@TableField("goods_name")private String goodsName;@TableField("count")private int count;
}

package org.example.dao;import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.example.entity.OrderDetails;public interface OrderDetailsMapper extends BaseMapper<OrderDetails> {
}

package org.example.service;import com.baomidou.mybatisplus.extension.service.IService;
import org.example.entity.OrderDetails;public interface OrderDetailsService extends IService<OrderDetails> {}

 然后编写业务代码，分布式事务的调用，模拟扣款和扣库存

• seata-demo1

feign调用

package org.example.client;import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;@FeignClient(value = "seata-demo2-service")
public interface Demo2Client {@RequestMapping("order/addCount")ResponseEntity<String> addCount(@RequestParam("count") int count);
}

MoneyService

package org.example.service;import com.baomidou.mybatisplus.extension.service.IService;
import org.example.entity.Money;public interface MoneyService extends IService<Money> {void changeMoney(Money money,Double num);
}

MoneyServiceImpl

package org.example.service;import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.springframework.stereotype.Service;
import org.example.dao.MoneyMapper;
import org.example.entity.Money;@Service
public class MoneyServiceImpl extends ServiceImpl<MoneyMapper, Money> implements MoneyService{public void changeMoney(Money money, Double num) {Double bankMoney = money.getBankMoney();if (bankMoney >= num) {money.setBankMoney(bankMoney - num);this.updateById(money);}else{throw new RuntimeException("余额不足");}}
}

TransService

package org.example.service;public interface TransService {void globalRollBackDemo(int orderCount);
}

TransServiceImpl

package org.example.service;import lombok.extern.slf4j.Slf4j;
import org.example.client.Demo2Client;
import org.example.entity.Money;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;import java.util.List;@Service
@Slf4j
public class TransServiceImpl implements TransService {@Autowiredprivate MoneyService moneyService;@Autowiredprivate Demo2Client demo2Client;/*** 分布式事务   回滚例子*/public void globalRollBackDemo(int orderCount) {log.info("=================开始扣钱========================");List<Money> list = moneyService.list();Money money = list.get(0);Double bankMoney = money.getBankMoney();log.info("=================查询到银行余额为："+bankMoney+",开始扣款：20=================");moneyService.changeMoney(money,20D);log.info("=================扣款成功，开始扣库存，扣减库存为："+orderCount+"========================");demo2Client.addCount(orderCount);}
}

MoneyController

package org.example.controller;import org.example.client.Demo2Client;
import org.example.service.TransService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;@Controller
@RequestMapping("money")
public class MoneyController {@Autowiredprivate TransService transService;@RequestMapping("test/globalTransactional/fail")public ResponseEntity<String> testGTRollBack() {transService.globalRollBackDemo(60);return new ResponseEntity<String>("sucess",HttpStatus.OK);}@RequestMapping("test/globalTransactional/sucess")public ResponseEntity<String> testGTSucess() {transService.globalRollBackDemo(40);return new ResponseEntity<String>("sucess",HttpStatus.OK);}}

SeataDemo1Application

package org.example;import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;@SpringBootApplication
@EnableDiscoveryClient
@MapperScan("org.example.dao")
@EnableFeignClients
public class SeataDemo1Application
{public static void main( String[] args ){SpringApplication.run(SeataDemo1Application.class,args);}
}

• seata-demo2

OrderDetailsController

package org.example.controller;import org.example.entity.OrderDetails;
import org.example.service.OrderDetailsService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;@Controller
@RequestMapping("order")
public class OrderDetailsController {@Autowiredprivate OrderDetailsService orderService;@RequestMapping("addCount")public ResponseEntity<String> addCount(@RequestParam("count") Integer count) {orderService.updateOrderDetails(count);return new ResponseEntity<String>("success",HttpStatus.OK);}}

OrderDetailsService

package org.example.service;import com.baomidou.mybatisplus.extension.service.IService;
import org.example.entity.OrderDetails;public interface OrderDetailsService extends IService<OrderDetails> {//  修改库存剩余void updateOrderDetails(Integer count);}

OrderDetailsServiceImpl

package org.example.service;import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import lombok.extern.slf4j.Slf4j;
import org.example.dao.OrderDetailsMapper;
import org.example.entity.OrderDetails;
import org.springframework.stereotype.Service;import java.util.List;@Service
@Slf4j
public class OrderDetailsServiceImpl extends ServiceImpl<OrderDetailsMapper, OrderDetails> implements OrderDetailsService {@Overridepublic void updateOrderDetails(Integer count) {List<OrderDetails> list = this.list();// 取第一个进行OrderDetails orderDetails = list.get(0);if (orderDetails.getCount()>=count) {int sum = orderDetails.getCount() - count;orderDetails.setCount(sum);this.updateById(orderDetails);log.info("库存扣减成功");}else{throw new RuntimeException("库存为："+list.get(0).getCount()+"不足，开始回滚");}}
}

SeataDemo2Application

package org.example;import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;@SpringBootApplication
@EnableDiscoveryClient
@MapperScan("org.example.dao")
@EnableFeignClients
public class SeataDemo2Application
{public static void main( String[] args ){SpringApplication.run(SeataDemo2Application.class,args);}
}

---

XA模式：

导入依赖

•  可以在公共的服务，或者私有的服务中导入seata的jar包
• jar包的版本如果和Spring-Cloud是同一个系列的（见版本选择），可以不指定，如果不是一个系列的，则需要指定版本（和部署的版本一致）
• 本教程是将jar包放入到公共服务中，并且指定版本号

<!-- 注意一定要引入对版本，要引入spring-cloud版本seata，而不是springboot版本的seata--><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-seata</artifactId><!-- 排除掉springcloud默认的seata版本，以免版本不一致出现问题--><exclusions><exclusion><groupId>io.seata</groupId><artifactId>seata-spring-boot-starter</artifactId></exclusion><exclusion><groupId>io.seata</groupId><artifactId>seata-all</artifactId></exclusion></exclusions></dependency><dependency><groupId>io.seata</groupId><artifactId>seata-spring-boot-starter</artifactId><version>1.7.0</version></dependency>

添加seata的相关配置

 在nacos管理的配置中，找到seata-demo1和seata-demo2的配置，添加如下配置：

#seata客户端配置
seata:enabled: trueapplication-id: seata_txtx-service-group: seata_tx_groupservice:vgroup-mapping:seata_tx_group: defaultregistry:type: nacosnacos:application: seata-serverserver-addr: 127.0.0.1:8848namespace:group: SEATA_GROUPdata-source-proxy-mode: XA

开启分布式事务---XA模式

• 在需要开启分布式事务的地方使用   @GlobalTransactional 修饰即可
• 本地事务，建议加上  @Transactional
• 例如我们要对，上面的扣钱和扣库存业务，添加分布式事务，只需要在seata-demo1的

  TransServiceImpl添加@GlobalTransactional

• 然后在本地事务使用@Transactional修饰
• 如：seata-demo1中的 MoneyServiceImpl 以及seata-demo2中的 OrderDetailsServiceImpl

这样，分布式事务XA模式就实现了 

---

AT模式：

        AT模式和XA模式在实现上基本没有区别，只需要将YML文件中的XA改为AT即可

---

TCC模式：

        关于TCC模式的原理，业务悬挂，空回滚等原理，以及TCC专用的注解这些就不说了，详情可以看上面的视频，这里仅仅是讲怎么实现。

        基于上面搭出的框架，按照下面的步骤来编写TCC模式

        TCC模式是在AT模式上进行改造的，所以YML的写法和AT模式一样

修改YML配置

seata-demo1

server:port: 8081
spring:nacos:discovery:server-addr: localhost:8848username: nacospassword: nacosdatasource:driver-class-name: com.mysql.cj.jdbc.Driverurl: jdbc:mysql://localhost:3306/seata_db1?characterEncoding=UTF-8username: rootpassword: 123888
#seata客户端配置
seata:enabled: trueapplication-id: seata_txtx-service-group: seata_tx_groupservice:vgroup-mapping:seata_tx_group: defaultregistry:type: nacosnacos:application: seata-serverserver-addr: 127.0.0.1:8848namespace:group: SEATA_GROUPdata-source-proxy-mode: AT

 seata-demo2

server:port: 8080
spring:nacos:discovery:server-addr: localhost:8848username: nacospassword: nacosdatasource:driver-class-name: com.mysql.cj.jdbc.Driverurl: jdbc:mysql://localhost:3306/seata_db2?characterEncoding=UTF-8username: rootpassword: 123888
#seata客户端配置
seata:enabled: trueapplication-id: seata_txtx-service-group: seata_tx_groupservice:vgroup-mapping:seata_tx_group: defaultregistry:type: nacosnacos:application: seata-serverserver-addr: 127.0.0.1:8848namespace:group: SEATA_GROUPdata-source-proxy-mode: AT

创建数据库

         可以在上述seata_db1数据库中创建两个数据库：t_account和t_account_tx

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;-- ----------------------------
-- Table structure for t_account
-- ----------------------------
DROP TABLE IF EXISTS `t_account`;
CREATE TABLE `t_account`  (`id` INT NOT NULL AUTO_INCREMENT,`user_id` VARCHAR(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,`money` INT NULL DEFAULT 0,PRIMARY KEY (`id`) USING BTREE
) ENGINE = INNODB AUTO_INCREMENT = 2 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = DYNAMIC;-- ----------------------------
-- Records of t_account
-- ----------------------------
INSERT INTO `t_account` VALUES (1, 'U100000', 900);-- ----------------------------
-- Table structure for t_account_tx
-- ----------------------------
DROP TABLE IF EXISTS `t_account_tx`;
CREATE TABLE `t_account_tx`  (`id` BIGINT NOT NULL AUTO_INCREMENT COMMENT '主键',`tx_id` VARCHAR(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '事务id',`freeze_money` INT NULL DEFAULT NULL COMMENT '冻结金额',`state` INT NULL DEFAULT NULL COMMENT '状态 0try 1confirm 2cancel',PRIMARY KEY (`id`) USING BTREE
) ENGINE = INNODB AUTO_INCREMENT = 3 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = DYNAMIC;

        可以在上述seata_db2数据库中创建两个数据库：t_order和t_order_tx

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;-- ----------------------------
-- Table structure for t_order
-- ----------------------------
DROP TABLE IF EXISTS `t_order`;
CREATE TABLE `t_order`  (`id` INT NOT NULL AUTO_INCREMENT,`user_id` VARCHAR(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,`commodity_code` VARCHAR(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL,`count` INT NULL DEFAULT 0,`money` INT NULL DEFAULT 0,PRIMARY KEY (`id`) USING BTREE
) ENGINE = INNODB AUTO_INCREMENT = 25 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = DYNAMIC;-- ----------------------------
-- Records of t_order
-- ------------------------------ ----------------------------
-- Table structure for t_order_tx
-- ----------------------------
DROP TABLE IF EXISTS `t_order_tx`;
CREATE TABLE `t_order_tx`  (`id` BIGINT NOT NULL AUTO_INCREMENT COMMENT '主键',`tx_id` VARCHAR(255) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL COMMENT '事务id',`state` INT NULL DEFAULT NULL COMMENT '状态 0try 1confirm 2cancel',PRIMARY KEY (`id`) USING BTREE
) ENGINE = INNODB AUTO_INCREMENT = 1 CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = DYNAMIC;

编写Mybatis-plus的三层及业务层

 seata-demo1

实体

package org.example.entity;import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;@Data
@TableName("t_account")
public class Account {@TableId(type = IdType.AUTO)private Integer id;private String userId;private int money;
}

package org.example.entity;import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;@Data
@TableName("t_account_tx")
public class AccountTX {public static final int STATE_TRY = 0;public static final int STATE_CONFIRM = 1;public static final int STATE_CANCEL = 2;@TableId(type = IdType.AUTO)private Integer id;private String txId;private int freezeMoney;private int state = STATE_TRY;
}

dao层

package org.example.dao;import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.example.entity.Account;public interface AccountMapper  extends BaseMapper<Account> {
}

package org.example.dao;import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.example.entity.AccountTX;public interface AccountTXMapper extends BaseMapper<AccountTX> {
}

service层

interface接口

package org.example.service;import com.baomidou.mybatisplus.extension.service.IService;
import org.example.entity.Account;public interface IAccountService  extends IService<Account> {/*** 账户扣款* @param userId* @param money* @return*/void reduce(String userId, int money);
}

package org.example.service;import io.seata.rm.tcc.api.BusinessActionContext;
import io.seata.rm.tcc.api.BusinessActionContextParameter;
import io.seata.rm.tcc.api.LocalTCC;
import io.seata.rm.tcc.api.TwoPhaseBusinessAction;/*** TCC 二阶段提交业务接口*/
@LocalTCC
public interface IAccountTCCService {/*** try-预扣款*/@TwoPhaseBusinessAction(name="tryReduce", commitMethod = "confirm", rollbackMethod = "cancel")void tryReduce(@BusinessActionContextParameter(paramName = "userId") String userId,@BusinessActionContextParameter(paramName = "money") int money);/*** confirm-提交* @param ctx* @return*/boolean confirm(BusinessActionContext ctx);/*** cancel-回滚* @param ctx* @return*/boolean cancel(BusinessActionContext ctx);
}

实现层

package org.example.service;import org.example.dao.AccountMapper;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.example.entity.Account;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;@Service
public class AccountServiceImpl extends ServiceImpl<AccountMapper, Account> implements IAccountService {@Override@Transactionalpublic void reduce(String userId, int money) {Account one = lambdaQuery().eq(Account::getUserId, userId).one();if(one != null && one.getMoney() < money){throw new RuntimeException("Not Enough Money ...");}lambdaUpdate().setSql("money = money - " + money).eq(Account::getUserId, userId).update();}
}

package org.example.service;import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.baomidou.mybatisplus.core.conditions.update.LambdaUpdateWrapper;
import io.seata.core.context.RootContext;
import io.seata.rm.tcc.api.BusinessActionContext;
import org.example.dao.AccountMapper;
import org.example.dao.AccountTXMapper;
import org.example.entity.Account;
import org.example.entity.AccountTX;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;@Service
public class AccountTCCServiceImpl  implements IAccountTCCService {@Autowiredprivate AccountMapper accountMapper;@Autowiredprivate AccountTXMapper accountTXMapper;@Overridepublic void tryReduce(String userId, int money) {System.err.println("-----------tryReduce-------------" + RootContext.getXID());//业务悬挂AccountTX accountTX = accountTXMapper.selectOne(new LambdaQueryWrapper<AccountTX>().eq(AccountTX::getTxId, RootContext.getXID()));if (accountTX != null){//存在，说明已经canel执行过类，拒绝服务return;}Account one = accountMapper.selectOne(new LambdaQueryWrapper<Account>().eq(Account::getUserId, userId));if(one != null && one.getMoney() < money){throw new RuntimeException("Not Enough Money ...");}LambdaUpdateWrapper<Account> wrapper = new LambdaUpdateWrapper<>();wrapper.setSql("money = money - " + money);wrapper.eq(Account::getUserId, userId);accountMapper.update(null, wrapper);AccountTX tx = new AccountTX();tx.setFreezeMoney(money);tx.setTxId(RootContext.getXID());tx.setState(AccountTX.STATE_TRY);accountTXMapper.insert(tx);}@Overridepublic boolean confirm(BusinessActionContext ctx) {System.err.println("-----------confirm-------------");//删除记录int ret = accountTXMapper.delete(new LambdaQueryWrapper<AccountTX>().eq(AccountTX::getTxId, ctx.getXid()));return ret == 1;}@Overridepublic boolean cancel(BusinessActionContext ctx) {System.err.println("-----------cancel-------------");String userId = ctx.getActionContext("userId").toString();String money = ctx.getActionContext("money").toString();AccountTX accountTX = accountTXMapper.selectOne(new LambdaQueryWrapper<AccountTX>().eq(AccountTX::getTxId, ctx.getXid()));if (accountTX == null){//为空， 空回滚accountTX = new AccountTX();accountTX.setTxId(ctx.getXid());accountTX.setState(AccountTX.STATE_CANCEL);if(money != null){accountTX.setFreezeMoney(Integer.parseInt(money));}accountTXMapper.insert(accountTX);return true;}//幂等处理if(accountTX.getState() == AccountTX.STATE_CANCEL){return true;}//恢复余额accountMapper.update(null, new LambdaUpdateWrapper<Account>().setSql("money = money + " + money).eq(Account::getUserId, userId));accountTX.setFreezeMoney(0);accountTX.setState(AccountTX.STATE_CANCEL);int ret = accountTXMapper.updateById(accountTX);return ret == 1;}
}

controller层

package org.example.controller;import org.example.service.IAccountTCCService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;@RestController
@RequestMapping("accounts")
public class AccountController {//@Autowired//private IAccountService accountService;@Autowiredprivate IAccountTCCService accountTCCService;@GetMapping(value = "/reduce")public String reduce(String userId, int money) {try {accountTCCService.tryReduce(userId, money);} catch (Exception exx) {exx.printStackTrace();return "FAIL";}return "SUCCESS";}}

启动类

package org.example;import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;@SpringBootApplication
@EnableDiscoveryClient
@MapperScan("org.example.dao")
@EnableFeignClients
public class SeataDemo1Application
{public static void main( String[] args ){SpringApplication.run(SeataDemo1Application.class,args);}
}

seata-demo2

实体层

package org.example.entity;import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;@Data
@TableName("t_order")
public class Order {@TableId(type = IdType.AUTO)private Integer id;private String userId;private String commodityCode;private Integer count;private Integer money;
}

package org.example.entity;import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;@Data
@TableName("t_order_tx")
public class OrderTX {public static final int STATE_TRY = 0;public static final int STATE_CONFIRM = 1;public static final int STATE_CANCEL = 2;@TableId(type = IdType.AUTO)private Integer id;private String txId;private int state = STATE_TRY;
}

dao层

package org.example.dao;import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.example.entity.Order;public interface OrderMapper  extends BaseMapper<Order> {
}

package org.example.dao;import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.example.entity.OrderTX;public interface OrderTXMapper extends BaseMapper<OrderTX> {
}

service层

interface层

package org.example.service;import com.baomidou.mybatisplus.extension.service.IService;
import org.example.entity.Order;public interface IOrderService  extends IService<Order> {/*** 创建订单*/void create(String userId, String commodityCode, int orderCount);
}

package org.example.service;import io.seata.rm.tcc.api.BusinessActionContext;
import io.seata.rm.tcc.api.BusinessActionContextParameter;
import io.seata.rm.tcc.api.LocalTCC;
import io.seata.rm.tcc.api.TwoPhaseBusinessAction;/*** TCC 二阶段提交业务接口*/
@LocalTCC
public interface IOrderTCCService {/*** try-预扣款*/@TwoPhaseBusinessAction(name="tryCreate", commitMethod = "confirm", rollbackMethod = "cancel")void tryCreate(@BusinessActionContextParameter(paramName = "userId") String userId,@BusinessActionContextParameter(paramName = "commodityCode") String commodityCode,@BusinessActionContextParameter(paramName = "orderCount") int orderCount);/*** confirm-提交* @param ctx* @return*/boolean confirm(BusinessActionContext ctx);/*** cancel-回滚* @param ctx* @return*/boolean cancel(BusinessActionContext ctx);}

实现层

package org.example.service;import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.example.entity.Order;
import org.example.feign.AccountFeignClient;
import org.example.dao.OrderMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;@Service
@Transactional
public class OrderServiceImpl extends ServiceImpl<OrderMapper, Order> implements IOrderService {@Autowiredprivate AccountFeignClient accountFeignClient;@Override@Transactionalpublic void create(String userId, String commodityCode, int count) {// 定单总价 = 订购数量(count) * 商品单价(100)int orderMoney = count * 100;// 生成订单Order order = new Order();order.setCount(count);order.setCommodityCode(commodityCode);order.setUserId(userId);order.setMoney(orderMoney);super.save(order);// 调用账户余额扣减String result = accountFeignClient.reduce(userId, orderMoney);if (!"SUCCESS".equals(result)) {throw new RuntimeException("Failed to call Account Service. ");}}
}

package org.example.service;import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import io.seata.core.context.RootContext;
import io.seata.rm.tcc.api.BusinessActionContext;
import org.example.dao.OrderMapper;
import org.example.dao.OrderTXMapper;
import org.example.entity.Order;
import org.example.entity.OrderTX;
import org.example.feign.AccountFeignClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;@Service
public class OrderTCCServiceImpl  implements IOrderTCCService {@Autowiredprivate AccountFeignClient accountFeignClient;@Autowiredprivate OrderMapper orderMapper;@Autowiredprivate OrderTXMapper orderTXMapper;@Overridepublic void tryCreate(String userId, String commodityCode, int count) {System.err.println("---------tryCreate-----------");//业务悬挂OrderTX orderTX = orderTXMapper.selectOne(new LambdaQueryWrapper<OrderTX>().eq(OrderTX::getTxId, RootContext.getXID()));if (orderTX != null){//存在，说明已经canel执行过类，拒绝服务return;}// 定单总价 = 订购数量(count) * 商品单价(100)int orderMoney = count * 100;// 生成订单Order order = new Order();order.setCount(count);order.setCommodityCode(commodityCode);order.setUserId(userId);order.setMoney(orderMoney);orderMapper.insert(order);OrderTX tx = new OrderTX();tx.setTxId(RootContext.getXID());tx.setState(OrderTX.STATE_TRY);orderTXMapper.insert(tx);// 调用账户余额扣减String result = accountFeignClient.reduce(userId, orderMoney);if (!"SUCCESS".equals(result)) {throw new RuntimeException("Failed to call Account Service. ");}}@Overridepublic boolean confirm(BusinessActionContext ctx) {System.err.println("---------confirm-----------");//删除记录int ret = orderTXMapper.delete(new LambdaQueryWrapper<OrderTX>().eq(OrderTX::getTxId, ctx.getXid()));return ret == 1;}@Overridepublic boolean cancel(BusinessActionContext ctx) {System.err.println("---------cancel-----------" );String userId = ctx.getActionContext("userId").toString();String commodityCode = ctx.getActionContext("commodityCode").toString();OrderTX orderTX = orderTXMapper.selectOne(new LambdaQueryWrapper<OrderTX>().eq(OrderTX::getTxId, ctx.getXid()));if (orderTX == null){//为空， 空回滚orderTX = new OrderTX();orderTX.setTxId(ctx.getXid());orderTX.setState(OrderTX.STATE_CANCEL);orderTXMapper.insert(orderTX);return true;}//幂等处理if(orderTX.getState() == OrderTX.STATE_CANCEL){return true;}//恢复余额orderMapper.delete(new LambdaQueryWrapper<Order>().eq(Order::getUserId, userId).eq(Order::getCommodityCode, commodityCode));orderTX.setState(OrderTX.STATE_CANCEL);int ret = orderTXMapper.updateById(orderTX);return ret == 1;}
}

controller层

package org.example.controller;import org.example.service.IOrderTCCService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;@RestController
@RequestMapping("orders")
public class OrderController {@Autowiredprivate IOrderTCCService orderTCCService;@GetMapping(value = "/create")public String create(String userId, String commodityCode, int orderCount) {try {orderTCCService.tryCreate(userId, commodityCode, orderCount);} catch (Exception exx) {exx.printStackTrace();return "FAIL";}return "SUCCESS";}
}

feign层

package org.example.feign;import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;@FeignClient(name = "seata-demo2-service")
public interface AccountFeignClient {@GetMapping("/accounts/reduce")String reduce(@RequestParam("userId") String userId, @RequestParam("money") int money);}

启动类

package org.example;import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;@SpringBootApplication
@EnableDiscoveryClient
@MapperScan("org.example.dao")
@EnableFeignClients
public class SeataDemo2Application
{public static void main( String[] args ){SpringApplication.run(SeataDemo2Application.class,args);}
}

测试

正常：http://localhost:8088/businesses/purchase?rollback=false&count=2

超库存：http://localhost:8088/businesses/purchase?rollback=false&count=12

超余额：http://localhost:8088/businesses/purchase?rollback=false&count=8

---

SAGA模式：

        saga模式适用于长事务，如银行API调用，等繁杂的事务处理