SEATA 分布式事务入门DEMO

Simple Extensible Autonomous Transacation Architecture，seata是简单的、可扩展、自主性高的分布式架构

SEATA Server Configure

因我们使用正式的1.0.0-GA 版本，网上大多数找到的说明都是0.X版本，有不少变动，比如，在server中取消了db_store.sql的脚本，如找不到相关内容，可以通过源码来查找，比如db脚本源码：mysql db script

1. 下载 seata-server

2. 创建数据库（seata）,可自定义，在file.conf中要用到。

   -- -------------------------------- 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;
   

3. 编辑file.conf配置文件

   service {
     #transaction service group mapping
     vgroup_mapping.sunrise_tx_group = "default"
     #only support when registry.type=file, please don't set multiple addresses
     default.grouplist = "127.0.0.1:8091"
     #disable seata
     disableGlobalTransaction = false
     #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"
   }
   
   ## transaction log store, only used in seata-server
   store {
     ## store mode: file、db
     mode = "db"
   
     ## file store property
     file {
       ## store location dir
       dir = "sessionStore"
     #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"
   }
   
   ## transaction log store, only used in seata-server
   store {
     ## store mode: file、db
     mode = "db"
   
     ## file store property
     file {
       ## store location dir
       dir = "sessionStore"
     }
   
     ## database store property
     db {
       ## the implement of javax.sql.DataSource, such as DruidDataSource(druid)/BasicDataSource(dbcp) etc.
       datasource = "dbcp"
       ## mysql/oracle/h2/oceanbase etc.
       db-type = "mysql"
       driver-class-name = "com.mysql.jdbc.Driver"
       url = "jdbc:mysql://localhost:3306/seata"
       user = "wr"
       password = "wr"
       min-conn = 1
       max-conn = 3
       global.table = "global_table"
       branch.table = "branch_table"
       lock-table = "lock_table"
       query-limit = 100
     }
   }
   

4. 编辑conf/regiester.conf

   registry {
     # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
     # 更改1
     type = "eureka"
   
     nacos {
       serverAddr = "localhost"
       namespace = ""
       cluster = "default"
     }
     eureka {
     	# 更改2
       serviceUrl = "http://localhost:21001/eureka"
       application = "default"
       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"
     }
   }
   

   本次实现，我们还没有添加configration的时候，因此只需要更改register块中的相关属性即可，在后续我们实现了nacos config之后，再同步更新这里。

5. 启动服务端

   [root@localhost.localdomain /usr/local/geekplus/server/seata]# bin/seata-server.sh
   

在eureka中看到如下8091端口的服务之后，即启动seata-server正常！

Client Configure

AT Model

需要在每一个业务库中添加数据表undo_log.

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 AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

Broadway-Demo

使用Springboot项目有一个小规律，我叫它为使用三部曲。

依broadway-ws-tally-service项目为例：

• 第一步：加依赖

          <!--seata-->
          <dependency>
              <groupId>com.alibaba.cloud</groupId>
              <artifactId>spring-cloud-alibaba-seata</artifactId>
              <version>2.1.0.RELEASE</version>
              <exclusions>
                  <exclusion>
                      <artifactId>seata-all</artifactId>
                      <groupId>io.seata</groupId>
                  </exclusion>
              </exclusions>
          </dependency>
          <dependency>
              <groupId>io.seata</groupId>
              <artifactId>seata-all</artifactId>
              <version>1.0.0</version>
          </dependency>
  

• 第二步：开启注解

  @SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
  

  在这里需要说明一下，我们需要排除掉SpringBoot默认自动注入的DataSourceAutoConfigurationBean, 因为SEATA是基于数据源拦截来实现的分布式事务，因此，我们需要自定义数据源配置信息：

  package com.geekplus.broadway.ws.tally.application;
  
  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;
  
  @Configuration
  public class DataSourceConfiguration {
      @Bean
      @ConfigurationProperties(prefix = "spring.datasource")
      public DataSource druidDataSource(){
          DruidDataSource druidDataSource = new DruidDataSource();
          return druidDataSource;
      }
  
      @Primary
      @Bean("dataSource")
      public DataSourceProxy dataSource(DataSource druidDataSource){
          return new DataSourceProxy(druidDataSource);
      }
  
      @Bean
      public SqlSessionFactory sqlSessionFactory(DataSourceProxy dataSourceProxy)throws Exception{
          SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
          sqlSessionFactoryBean.setDataSource(dataSourceProxy);
          sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver()
                  .getResources("classpath*:/com/geekplus/*.xml"));
          sqlSessionFactoryBean.setTransactionFactory(new SpringManagedTransactionFactory());
          return sqlSessionFactoryBean.getObject();
      }
  }
  

  该配置类，一般放在与启动类相同的目录即可！

• 第三部：改配置

  spring:
    cloud:
      alibaba:
        seata:
          tx-service-group: sunrise_tx_group
  

  TIPS:
  
  tx-service-group 一定要server，client都要保持一致，否则能坑死你！
  
  tx-service-group 一定要server，client都要保持一致，否则能坑死你！
  
  tx-service-group 一定要server，client都要保持一致，否则能坑死你！

以上三步是大多数SpringBoot 项目的通用做法，当然我们的SEATA暂时还不是那么完善，配置信息目前还不支持在application.yml中配置完全，因此，我们需要2个核心的client 配置文件file.conf和register.conf.

• file.conf 该文件主要是用于连接RM的，我们只需要关注上面所说的tx-service-group就行，其他配置默认就可以。

  transport {
    # tcp udt unix-domain-socket
    type = "TCP"
    #NIO NATIVE
    server = "NIO"
    #enable heartbeat
    heartbeat = true
    # the client batch send request enable
    enable-client-batch-send-request = 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 {
    #transaction service group mapping
    vgroup_mapping.sunrise_tx_group = "default"
    #only support when registry.type=file, please don't set multiple addresses
    default.grouplist = "127.0.0.1:8091"
    #disable seata
    disableGlobalTransaction = false
  }
  
  client {
    rm {
      async.commit.buffer.limit = 10000
      lock {
        retry.internal = 10
        retry.times = 30
        retry.policy.branch-rollback-on-conflict = true
      }
      report.retry.count = 5
      table.meta.check.enable = false
      report.success.enable = true
    }
    tm {
      commit.retry.count = 5
      rollback.retry.count = 5
    }
    undo {
      data.validation = true
      log.serialization = "jackson"
      log.table = "undo_log"
    }
    log {
      exceptionRate = 100
    }
    support {
      # auto proxy the DataSource bean
      spring.datasource.autoproxy = false
    }
   }
  

• register.conf该文件是用于指定注册中心相关配置的，它有2个核心block：

  • registry块
    
    此模板表明我们的注册中心使用类型，需要根据type设置来同步更新使用的配置信息，比如我们使用的eureka，因此我们更新eureka.serviceUrl="http://172.16.1.187:21001/eureka".

  • config 块
    
    该模块用来设置我们的配置中心相关配置（此处后续更新，我们会选择apollo）

  registry {
    # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
    type = "eureka"
  
    nacos {
      serverAddr = "localhost"
      namespace = ""
      cluster = "default"
    }
    eureka {
      serviceUrl = "http://172.16.1.187:21001/eureka"
      application = "default"
      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"
    }
  }