一、前言

通过以下系列章节：

我们完成了对Seata及其AT、XA、TCC、Saga事务模式的理论和多维度对比总结，并通过业务示例搭建对其使用也有了深入的了解。

分库分表是数据库扩展中最常用的处理方法，ShardingSphere 作为使用最广泛的数据分片中间件，ShardingSphere 实现了对分布式事务Seata的支持，保证了数据一致性。在这篇文章中，我们使用ShardingSphere整合Seata在数据分片场景下进行（远程）分布式事务调用，并对集成过程中需注意的事项进行详解说明。

为删减不必要的篇幅，本章会应用到一些往期章节的内容，现整理如下，请自行查阅了解：

ShardingSphere实现数据分片实现相关内容：

Spring Boot集成ShardingSphere实现数据分片（一） | Spring Cloud 40

Spring Boot集成ShardingSphere实现数据分片（二） | Spring Cloud 41

Spring Boot集成ShardingSphere实现数据分片（三） | Spring Cloud 42

ShardingSphere 5.3 系列配置升级指南：

ShardingSphere 5.3 系列Spring 配置升级指南 | Spring Cloud 47

Seata利用AT模式分布式事务示例相关内容：

docker-compose 实现Seata Server高可用部署 | Spring Cloud 51

Seata AT 模式理论学习、事务隔离及部分源码解析 | Spring Cloud 52

Spring Boot集成Seata利用AT模式分布式事务示例 | Spring Cloud 53

二、项目总体结构

在这里插入图片描述

目录结构解析：

common-at：公共模块，包含：实体类、openfeign接口、统一异常处理等。
account-at：账户服务，可以查询/修改用户的账户信息。为RM (Resource Manager) - 资源管理器 角色。

管理分支事务处理的资源，与TC交互以注册分支事务和报告分支事务的状态，并驱动分支事务提交或回滚。
storage-at：仓储服务，可以查询/修改商品的库存数量。为RM (Resource Manager) - 资源管理器 角色。

以上部分内容请参照：Spring Boot集成Seata利用AT模式分布式事务示例 | Spring Cloud 53，以此为基础无任何改动。

order-sharding-database-at：订单服务，可以下订单。为TM (Transaction Manager) - 事务管理器 角色。

本章重点，使用 ShardingSphere 定义数据分片规则，集成Seata 开启分布式事务，并进行远程微服务调用。

三、order-sharding-database-at 搭建

3.1 完整依赖

seata/openfeign-at/order-sharding-database-at/pom.xml：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>openfeign-at</artifactId>
        <groupId>com.gm</groupId>
        <version>0.0.1-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>order-sharding-database-at</artifactId>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>
        <dependency>
            <groupId>com.gm</groupId>
            <artifactId>common-at</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-bootstrap</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-loadbalancer</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>com.mysql</groupId>
            <artifactId>mysql-connector-j</artifactId>
        </dependency>
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.5.3.1</version>
        </dependency>
        <dependency>
            <groupId>com.gm</groupId>
            <artifactId>common-tcc</artifactId>
            <version>0.0.1-SNAPSHOT</version>
            <scope>compile</scope>
        </dependency>

        <!-- 解决shardingsphere集成依赖版本冲突和算法依赖包 -->
        <dependency>
            <groupId>org.yaml</groupId>
            <artifactId>snakeyaml</artifactId>
            <version>1.33</version>
        </dependency>
        <dependency>
            <groupId>org.apache.velocity</groupId>
            <artifactId>velocity-engine-core</artifactId>
            <version>2.3</version>
        </dependency>
        <dependency>
            <groupId>org.apache.shardingsphere</groupId>
            <artifactId>shardingsphere-jdbc-core</artifactId>
            <version>5.3.2</version>
        </dependency>
        <dependency>
            <groupId>org.apache.shardingsphere</groupId>
            <artifactId>shardingsphere-transaction-base-seata-at</artifactId>
            <version>5.3.2</version>
            <!-- 排除掉shardingsphere-transaction-base-seata-at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-all</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <!-- 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-->
        <!-- 引入spring-cloud-starter-alibaba-seata解决openfeign远程调用传递xid问题 -->
        <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-all</artifactId>
            <version>1.6.1</version>
            <!-- Could not deserialize ATN with version 4 (expected 3). -->
            <exclusions>
                <exclusion>
                    <groupId>org.antlr</groupId>
                    <artifactId>antlr4</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

请自行查看各依赖包上方注释，已对各情况进行详细说明。

3.2 完整配置文件

项目配置文件共分为以下四个：

bootstrap.yml
seata.conf
registry.conf
registry.conf

3.2.1 bootstrap.yml

server:
  port: 3012

spring:
  application:
    name: @artifactId@
  cloud:
    nacos:
      username: @nacos.username@
      password: @nacos.password@
      discovery:
        server-addr: ${
    
    NACOS_HOST:nacos1.kc}:${
    
    NACOS_PORT:8848}
  datasource:
    driver-class-name: org.apache.shardingsphere.driver.ShardingSphereDriver
    url: jdbc:shardingsphere:classpath:sharding.yaml

# 此处配置是为了实现利用openfeign传播xid
seata:
  enabled: true


management:
  endpoints:
    web:
      exposure:
        include: '*'

logging:
  level:
    io.seata: info

# mybatis-plus配置控制台打印完整带参数SQL语句
mybatis-plus:
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

注意事项：

seata.enabled=true 此配置是为了实现利用openfeign传播全局事务的xid。

3.2.2 seata.conf

client {
    
    
    application.id = order-sharding-database-at
    transaction.service.group = mygroup
}

参照以下源码对Seata进行相关配置，org.apache.shardingsphere.transaction.base.seata.at.SeataATShardingSphereTransactionManager：

在这里插入图片描述

事务管理器SeataATShardingSphereTransactionManager在初始化时会读取配置文件seata.conf，加载以上配置信息。

3.2.3 registry.conf

Seata注册中心及配置中心配置：

registry {
    
    
  type = "nacos"

  nacos {
    
    
    application = "seata-server"
    serverAddr = "192.168.0.31:8848"
    group = "DEFAULT_GROUP"
    namespace = "a4c150aa-fd09-4595-9afe-c87084b22105"
    cluster = "default"
    username = "nacos"
    password = "nacos"
  }
}

config {
    
    
  type = "nacos"

  nacos {
    
    
    serverAddr = "192.168.0.31:8848"
    namespace = "a4c150aa-fd09-4595-9afe-c87084b22105"
    group = "DEFAULT_GROUP"
    username = "nacos"
    password = "nacos"
    dataId = "seataServer.properties"
  }
}

3.2.4 sharding.yaml

shardingsphere定义数据分片规则和分布式事务配置：

dataSources:
  ds1:
    dataSourceClassName: com.zaxxer.hikari.HikariDataSource
    driverClassName: com.mysql.cj.jdbc.Driver
    jdbcUrl: jdbc:mysql://192.168.0.35:3306/db1?useUnicode=true&characterEncoding=UTF-8&rewriteBatchedStatements=true&allowMultiQueries=true&serverTimezone=Asia/Shanghai
    username: root
    password: '1qaz@WSX'
    connectionTimeoutMilliseconds: 30000
    idleTimeoutMilliseconds: 60000
    maxLifetimeMilliseconds: 1800000
    maxPoolSize: 50
    minPoolSize: 1

  ds2:
    dataSourceClassName: com.zaxxer.hikari.HikariDataSource
    driverClassName: com.mysql.cj.jdbc.Driver
    jdbcUrl: jdbc:mysql://192.168.0.46:3306/db2?useUnicode=true&characterEncoding=UTF-8&rewriteBatchedStatements=true&allowMultiQueries=true&serverTimezone=Asia/Shanghai
    username: root
    password: '1qaz@WSX'
    connectionTimeoutMilliseconds: 30000
    idleTimeoutMilliseconds: 60000
    maxLifetimeMilliseconds: 1800000
    maxPoolSize: 50
    minPoolSize: 1

rules:

  - !TRANSACTION
    defaultType: BASE
    providerType: Seata

  - !SHARDING
    # 数据分片规则配置
    tables:
      # 指定某个表的分片配置，逻辑表名
      t_share_order:
        # 这个配置是告诉sharding有多少个库和多少个表及所在实际的数据库节点，由数据源名 + 表名组成（参考 Inline 语法规则）
        actualDataNodes: ds$->{
    
    1..2}.t_share_order
        # 配置库分片策略
        databaseStrategy:
          # 用于单分片键的标准分片场景
          standard:
            # 分片列名称
            shardingColumn: id
            # 分片算法名称
            shardingAlgorithmName: t_share_order_database_inline
        # 分布式序列策略
        keyGenerateStrategy:
          # 自增列名称，缺省表示不使用自增主键生成器
          column: id
          # 分布式序列算法名称
          keyGeneratorName: snowflake
    # 分片算法配置
    shardingAlgorithms:
      # 分片算法名称
      t_share_order_database_inline:
        # 分片算法类型
        type: INLINE
        # 分片算法属性配置
        props:
          algorithm-expression: ds$->{
    
    id % 2 + 1}
    # 分布式序列算法配置（如果是自动生成的，在插入数据的sql中就不要传id，null也不行，直接插入字段中就不要有主键的字段）
    keyGenerators:
      # 分布式序列算法名称
      snowflake:
        # 分布式序列算法类型
        type: SNOWFLAKE

props:
  sql-show: true #显示sql

shardingsphere数据分片请见官网：
https://shardingsphere.apache.org/document/5.3.2/cn/user-manual/shardingsphere-jdbc/yaml-config/rules/sharding/

shardingsphere分布式事务支持请见官网：https://shardingsphere.apache.org/document/5.3.2/cn/user-manual/shardingsphere-jdbc/yaml-config/rules/transaction/

3.3 数据源配置

因sharding.yaml中配置的数据分片规则和使用Seata AT事务模式，故数据源如下：

3.3.1 ds1 建表语句

create DATABASE db1;
user db1;

-- ----------------------------
-- Table structure for t_share_order
-- ----------------------------
DROP TABLE IF EXISTS `t_share_order`;
CREATE TABLE `t_share_order`  (
  `id` bigint NOT NULL AUTO_INCREMENT,
  `user_id` varchar(255) CHARACTER SET utf8mb3 COLLATE utf8mb3_general_ci NULL DEFAULT NULL,
  `commodity_code` varchar(255) CHARACTER SET utf8mb3 COLLATE utf8mb3_general_ci NULL DEFAULT NULL,
  `count` int NULL DEFAULT 0,
  `money` decimal(10, 2) NULL DEFAULT 0.00,
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 1 CHARACTER SET = utf8mb3 COLLATE = utf8mb3_general_ci ROW_FORMAT = Dynamic;

-- for AT mode you must to init this sql for you business database. the seata server not need it.
CREATE TABLE IF NOT EXISTS `undo_log`
(
    `branch_id`     BIGINT       NOT NULL COMMENT 'branch transaction id',
    `xid`           VARCHAR(128) NOT NULL COMMENT 'global transaction id',
    `context`       VARCHAR(128) NOT NULL COMMENT 'undo_log context,such as serialization',
    `rollback_info` LONGBLOB     NOT NULL COMMENT 'rollback info',
    `log_status`    INT(11)      NOT NULL COMMENT '0:normal status,1:defense status',
    `log_created`   DATETIME(6)  NOT NULL COMMENT 'create datetime',
    `log_modified`  DATETIME(6)  NOT NULL COMMENT 'modify datetime',
    UNIQUE KEY `ux_undo_log` (`xid`, `branch_id`)
) ENGINE = InnoDB
  AUTO_INCREMENT = 1
  DEFAULT CHARSET = utf8mb4 COMMENT ='AT transaction mode undo table';

3.3.2 ds2 建表语句

create DATABASE db2;
user db2;

-- ----------------------------
-- Table structure for t_share_order
-- ----------------------------
DROP TABLE IF EXISTS `t_share_order`;
CREATE TABLE `t_share_order`  (
  `id` bigint NOT NULL AUTO_INCREMENT,
  `user_id` varchar(255) CHARACTER SET utf8mb3 COLLATE utf8mb3_general_ci NULL DEFAULT NULL,
  `commodity_code` varchar(255) CHARACTER SET utf8mb3 COLLATE utf8mb3_general_ci NULL DEFAULT NULL,
  `count` int NULL DEFAULT 0,
  `money` decimal(10, 2) NULL DEFAULT 0.00,
  PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB AUTO_INCREMENT = 1 CHARACTER SET = utf8mb3 COLLATE = utf8mb3_general_ci ROW_FORMAT = Dynamic;

-- for AT mode you must to init this sql for you business database. the seata server not need it.
CREATE TABLE IF NOT EXISTS `undo_log`
(
    `branch_id`     BIGINT       NOT NULL COMMENT 'branch transaction id',
    `xid`           VARCHAR(128) NOT NULL COMMENT 'global transaction id',
    `context`       VARCHAR(128) NOT NULL COMMENT 'undo_log context,such as serialization',
    `rollback_info` LONGBLOB     NOT NULL COMMENT 'rollback info',
    `log_status`    INT(11)      NOT NULL COMMENT '0:normal status,1:defense status',
    `log_created`   DATETIME(6)  NOT NULL COMMENT 'create datetime',
    `log_modified`  DATETIME(6)  NOT NULL COMMENT 'modify datetime',
    UNIQUE KEY `ux_undo_log` (`xid`, `branch_id`)
) ENGINE = InnoDB
  AUTO_INCREMENT = 1
  DEFAULT CHARSET = utf8mb4 COMMENT ='AT transaction mode undo table';

3.4 功能搭建

3.4.1 启动类

com/gm/seata/openfeign/OrderShardingDatabaseATApplication.java：

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
@EnableFeignClients("com.gm.seata.openfeign.feign")
public class OrderShardingDatabaseATApplication {
    
    

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

3.4.2 实体类

com/gm/seata/openfeign/entity/Order.java：

import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;
import java.math.BigDecimal;

@Data
@TableName("t_share_order")
public class Order {
    
    

    @TableId(type = IdType.ASSIGN_ID)
    private Long id;

    private String userId;

    private String commodityCode;

    private int count;

    private BigDecimal money;
}

注意事项：

此处的@TableName("t_share_order")与sharding.yaml中的逻辑表名相对应

字段userId上使用注解@TableId(type = IdType.ASSIGN_ID)表示主键生成策略使用mybatis-plus内置的雪花算法，且要求类型为Long ，而不能为long（策略不生效，id=0）。

3.4.3 Mapper类

com/gm/seata/openfeign/mapper/OrderMapper.java：

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.gm.seata.openfeign.entity.Order;
import org.apache.ibatis.annotations.Mapper;

@Mapper
public interface OrderMapper extends BaseMapper<Order> {
    
    

}

3.4.4 Service类

com/gm/seata/openfeign/service/OrderService.java：

public interface OrderService {
    
    

    /**
     * 创建订单
     *
     * @param userId
     * @param commodityCode
     * @param count
     * @return
     */
    boolean createOrder(String userId, String commodityCode, Integer count);
}

com/gm/seata/openfeign/service/impl/OrderServiceImpl.java：

import com.gm.seata.openfeign.entity.Order;
import com.gm.seata.openfeign.feign.AccountServiceApi;
import com.gm.seata.openfeign.feign.StorageServiceApi;
import com.gm.seata.openfeign.mapper.OrderMapper;
import com.gm.seata.openfeign.service.OrderService;
import io.seata.core.context.RootContext;
import io.seata.spring.annotation.GlobalTransactional;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import java.math.BigDecimal;

@Slf4j
@Service
public class OrderServiceImpl implements OrderService {
    
    

    @Autowired
    OrderMapper orderMapper;

    @Autowired
    StorageServiceApi storageServiceApi;

    @Autowired
    AccountServiceApi accountServiceApi;

    @Transactional
    /*@GlobalTransactional*/
    @Override
    public boolean createOrder(String userId, String commodityCode, Integer count) {
    
    

        String xid = RootContext.getXID();
        log.info("全局事务 xid：{}", xid);

        Order order = new Order();
        order.setCount(count);
        order.setCommodityCode(commodityCode);
        order.setUserId(userId);
        order.setMoney(new BigDecimal(count * 100.0));
        int i = orderMapper.insert(order);

        try {
    
    
            storageServiceApi.deduct(commodityCode, count);
        } catch (Exception e) {
    
    
            throw new RuntimeException(e.getMessage());
        }
        try {
    
    
            accountServiceApi.deduct(userId, new BigDecimal(count * 100.0));
        } catch (Exception e) {
    
    
            throw new RuntimeException(e.getMessage());
        }


        return i == 1;
    }
}

注意事项：

想要分布式事务生效，调用方法上必须添加注解@Transactional，此时因集成shardingsphere对Seata AT模式的支持，在TM (Transaction Manager) - 事务管理器 角色的调用方法上可不添加@GlobalTransactional注解

参考源码org.apache.shardingsphere.transaction.base.seata.at.SeataATShardingSphereTransactionManager：

在这里插入图片描述

在通过事务管理器SeataATShardingSphereTransactionManager开启事务时，会读取已存在的全局事务或创建新的全局事务，故无需显性添加@GlobalTransactional注解。

3.4.5 Controller类

com/gm/seata/openfeign/controller/OrderController.java：

import com.gm.seata.openfeign.service.OrderService;
import com.gm.seata.openfeign.util.ErrorEnum;
import com.gm.seata.openfeign.util.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@Slf4j
@RestController
public class OrderController {
    
    

    @Autowired
    OrderService orderService;

    /**
     * 商品下单购买
     *
     * @param userId
     * @param commodityCode
     * @param count
     * @return
     */
    @RequestMapping(value = "buy", method = RequestMethod.GET)
    public R<String> buy(@RequestParam("userId") String userId, @RequestParam("commodityCode") String commodityCode, @RequestParam("count") Integer count) {
    
    
        try {
    
    
            orderService.createOrder(userId, commodityCode, count);
            return R.ok("下单成功", "");
        } catch (Exception e) {
    
    
            e.printStackTrace();
            int code = Integer.parseInt(e.getMessage());
            return R.restResult("下单失败", code, ErrorEnum.getEnumByCode(code).getTitle());
        }
    }
}

四、示例测试

请求地址：http://127.0.0.1:3012/buy?userId=user1&count=2&commodityCode=iphone

每请求一次，扣除余额200元，扣除库存2个

4.1 全局事务提交成功

在这里插入图片描述

4.2 全局事务回滚成功

在这里插入图片描述

此时根据日志查看对应数据源的t_share_order表，发现其中并未新增数据。

ShardingSphere 5.3 整合 Seata 分布式事务 | Spring Cloud 61

一、前言

二、项目总体结构

三、order-sharding-database-at 搭建

3.1 完整依赖

3.2 完整配置文件

3.2.1 bootstrap.yml

3.2.2 seata.conf

3.2.3 registry.conf

3.2.4 sharding.yaml

3.3 数据源配置

3.3.1 ds1 建表语句

3.3.2 ds2 建表语句

3.4 功能搭建

3.4.1 启动类

3.4.2 实体类

3.4.3 Mapper类

3.4.4 Service类

3.4.5 Controller类

四、示例测试

4.1 全局事务提交成功

4.2 全局事务回滚成功

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