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

下载 seata-server

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;

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

  }

}

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。

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"

  }

}