springcloud-eureka-feign-mybatis-seata分布式事务实战

1、seata下载
seata-server：

2、技术选型及版本信息
注册中心：eureka
服务调用：feign
持久层框架：mybatis 2.1.1
数据库：mysql 8.0.17
springboot：2.2.2.RELEASE
springcloud：Hoxton.SR1
jdk：1.8
seata：1.0.0
3、服务结构

事务发起方服务（TM）：commodity-service
事务方服务（RM）：orders-service、pay-service、stock-service、score-service、store-service
事务协调方服务（TC）：/seata-1.0.0/server（seata-server包解压得到）
4、服务方配置修改（seata-server）
（1）、resources/registry.conf

#服务注册中心配置
registry {
  # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
  type = "***eureka***"	#修改为注册中心使用eureka

  nacos {
    serverAddr = "localhost"
    namespace = ""
    cluster = "default"
  }
  eureka {
    serviceUrl = "http://localhost:50000/eureka"	#修改为eureka地址
    application = "seata-server"	#修改为seata-server服务名称
    weight = "1"
  }
  redis {
    serverAddr = "localhost:6379"
    db = "0"
  }
  zk {
    cluster = "default"
    serverAddr = "127.0.0.1:2181"
    session.timeout = 6000
    connect.timeout = 2000
  }
  consul {
    cluster = "default"
    serverAddr = "127.0.0.1:8500"
  }
  etcd3 {
    cluster = "default"
    serverAddr = "http://localhost:2379"
  }
  sofa {
    serverAddr = "127.0.0.1:9603"
    application = "default"
    region = "DEFAULT_ZONE"
    datacenter = "DefaultDataCenter"
    cluster = "default"
    group = "SEATA_GROUP"
    addressWaitTime = "3000"
  }
  file {
    name = "file.conf"
  }
}

#配置中心配置（无需修改）
config {
  # file、nacos 、apollo、zk、consul、etcd3
  type = "file"

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

（2）、resources/file.conf

service {
  #transaction service group mapping
  vgroup_mapping.fsp_tx_group = "seata-server" #修改这里，fsp_tx_group这个事务组名称是自定义的，但一定要与client端的这个配置一致！否则会报错！seata-server为seata-server服务名称
  #only support when registry.type=file, please don't set multiple addresses
  seata-server.grouplist = "127.0.0.1:8091" #如果上面fsp_tx_group的值修改为了seata-server，此处也修改为seata-server（默认名称为default）
  #disable seata
  disableGlobalTransaction = false
}

## transaction log store, only used in seata-server
store {
  ## store mode: file、db
  mode = "db" #如果使用数据库存储事务信息，将值修改为db

  ## file store property
  file {
    ## store location dir
    dir = "sessionStore"
  }

  ## database store property	mode=db时，事务日志会存储在这个配置的数据库里
  db {
    ## the implement of javax.sql.DataSource, such as DruidDataSource(druid)/BasicDataSource(dbcp) etc.
    datasource = "druid"	#修改为自己的数据源类型
    ## mysql/oracle/h2/oceanbase etc.
    db-type = "mysql"	#修改为自己的数据库类型
    driver-class-name = "com.mysql.cj.jdbc.Driver"	#修改数据库驱动
    url = "jdbc:mysql://localhost:3306/seata_server?serverTimezone=Asia/Shanghai"	#修改链接数据库的url
    user = "root"	#数据库登录用户
    password = "xzc"	#数据库登录密码
  }
}

（3）、如果第（2）步中事务日志采用数据库存储，需要创建三张表global_table，branch_table，lock_table

-- -------------------------------- The script used when storeMode is 'db' --------------------------------
-- the table to store GlobalSession data
CREATE TABLE IF NOT EXISTS `global_table`
(
    `xid`                       VARCHAR(128) NOT NULL,
    `transaction_id`            BIGINT,
    `status`                    TINYINT      NOT NULL,
    `application_id`            VARCHAR(32),
    `transaction_service_group` VARCHAR(32),
    `transaction_name`          VARCHAR(128),
    `timeout`                   INT,
    `begin_time`                BIGINT,
    `application_data`          VARCHAR(2000),
    `gmt_create`                DATETIME,
    `gmt_modified`              DATETIME,
    PRIMARY KEY (`xid`),
    KEY `idx_gmt_modified_status` (`gmt_modified`, `status`),
    KEY `idx_transaction_id` (`transaction_id`)
) ENGINE = InnoDB
  DEFAULT CHARSET = utf8;

-- the table to store BranchSession data
CREATE TABLE IF NOT EXISTS `branch_table`
(
    `branch_id`         BIGINT       NOT NULL,
    `xid`               VARCHAR(128) NOT NULL,
    `transaction_id`    BIGINT,
    `resource_group_id` VARCHAR(32),
    `resource_id`       VARCHAR(256),
    `branch_type`       VARCHAR(8),
    `status`            TINYINT,
    `client_id`         VARCHAR(64),
    `application_data`  VARCHAR(2000),
    `gmt_create`        DATETIME,
    `gmt_modified`      DATETIME,
    PRIMARY KEY (`branch_id`),
    KEY `idx_xid` (`xid`)
) ENGINE = InnoDB
  DEFAULT CHARSET = utf8;

-- the table to store lock data
CREATE TABLE IF NOT EXISTS `lock_table`
(
    `row_key`        VARCHAR(128) NOT NULL,
    `xid`            VARCHAR(96),
    `transaction_id` BIGINT,
    `branch_id`      BIGINT       NOT NULL,
    `resource_id`    VARCHAR(256),
    `table_name`     VARCHAR(32),
    `pk`             VARCHAR(36),
    `gmt_create`     DATETIME,
    `gmt_modified`   DATETIME,
    PRIMARY KEY (`row_key`),
    KEY `idx_branch_id` (`branch_id`)
) ENGINE = InnoDB
  DEFAULT CHARSET = utf8;

配置修改完成，等eureka启动后，启动seata-server

5、客户端配置
共有6个客户端，每个客户端都要做如下配置（只列举跟seata有关的配置）：
（1）seata依赖

        <dependency>
            <groupId>com.alibaba.cloud</groupId>
            <artifactId>spring-cloud-alibaba-seata</artifactId>
            <version>2.1.1.RELEASE</version>
        </dependency>

（2）、application.properties

#设置seata事务组
spring.cloud.alibaba.seata.tx-service-group=fsp_tx_group

事务组名称一定要跟seata-server中配置的一样
（3）、resources目录下新增registry.conf和file.conf文件
registry.conf：

registry {
  # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
  type = "eureka"	#修改为采用eureka为注册中心

  nacos {
    serverAddr = "localhost"
    namespace = ""
    cluster = "default"
  }
  eureka {
    serviceUrl = "http://localhost:50000/eureka"	#修改为eureka注册中心地址
    application = "commodity-service"	#修改为本服务的服务名
    weight = "1"
  }
  redis {
    serverAddr = "localhost:6379"
    db = "0"
  }
  zk {
    cluster = "default"
    serverAddr = "127.0.0.1:2181"
    session.timeout = 6000
    connect.timeout = 2000
  }
  consul {
    cluster = "default"
    serverAddr = "127.0.0.1:8500"
  }
  etcd3 {
    cluster = "default"
    serverAddr = "http://localhost:2379"
  }
  sofa {
    serverAddr = "127.0.0.1:9603"
    application = "default"
    region = "DEFAULT_ZONE"
    datacenter = "DefaultDataCenter"
    cluster = "default"
    group = "SEATA_GROUP"
    addressWaitTime = "3000"
  }
  file {
    name = "file.conf"
  }
}

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

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

file.conf：

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

service {
  #vgroup->rgroup
  vgroup_mapping.fsp_tx_group = "seata-server" #fsp_tx_group为事务组，与seata-server保持一致，seata-server为事务服务的名称（默认名称为default），也与seata-server中保持一致
  #only support single node
  seata-server.grouplist = "127.0.0.1:8091"	#此处seata-server与上面fsp_tx_group的值保持一致
  #degrade current not support
  enableDegrade = false
  #disable
  disable = false
  #unit ms,s,m,h,d represents milliseconds, seconds, minutes, hours, days, default permanent
  max.commit.retry.timeout = "-1"
  max.rollback.retry.timeout = "-1"
}

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

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

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

（4）、配置代理数据源
由于seata对数据源做了代理和接管，因此在每个分布式服务中，都要配置代理数据源

package com.xzc.esc.commodityservice.configs;



import com.alibaba.druid.pool.DruidDataSource;
import io.seata.rm.datasource.DataSourceProxy;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.transaction.SpringManagedTransactionFactory;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;

import javax.sql.DataSource;

/**
 * seata代理数据源配置
 * seata对数据源做了代理和接管，在每个参与分布式事务的服务中，都要做如下配置
 */
@Configuration
public class DatasourceConfig {

    @Bean
    @ConfigurationProperties(prefix = "spring.datasource")
    public DataSource druidDataSource() {
        return new DruidDataSource();
    }

    @Primary
    @Bean("dataSource")
    public DataSourceProxy dataSource(DataSource druidDataSource) {
        return new DataSourceProxy(druidDataSource);
    }

    @Bean
    public SqlSessionFactory sqlSessionFactoryBean(DataSourceProxy dataSourceProxy) throws Exception {
        SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        sqlSessionFactoryBean.setDataSource(dataSourceProxy);
        sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver()
                .getResources("classpath*:/mapper/*.xml"));//必须指定mapper的路径，否则会报Invalid bound statement (not found)错
        sqlSessionFactoryBean.setTransactionFactory(new SpringManagedTransactionFactory());
        return sqlSessionFactoryBean.getObject();
    }
}

（5）、解决循环依赖
服务启动类中，SpringBootApplication中需要排除自动配置类，以解决循环依赖

@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)

（6）、新增undo_log表
记录回滚时用到的操作

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

注：以上6个步骤是每个微服务都需要做的步骤

（7）、添加@GlobalTransactional注解
在事务调用服务上添加@GlobalTransactional，如下：

按照以上步骤就可以配置出基于springcloud、eureka、feign、mybatis、seata的分布式事务服务

参考：
seata-samples

https://github.com/seata/seata-samples/tree/master/springcloud-eureka-feign-mybatis-seata

http://seata.io/zh-cn/index.html