seata使用及避坑指南

由于公司项目一直没有整合分布式事务框架，最近查阅资料后觉得seata对代码的侵入性较小，所以决定整合seata。网上一堆博客搞得晕头转向，一路踩坑，最终还是搞定了。先来讲讲使用过程。

目前我的项目环境是：consul(注册中心) + oracle(数据库).

一、引入pom

<!--seata-->
<dependency>
   <groupId>com.alibaba.cloud</groupId>
   <artifactId>spring-cloud-alibaba-seata</artifactId>
   <version>2.2.0.RELEASE</version>
   <exclusions>
      <exclusion>
         <groupId>io.seata</groupId>
         <artifactId>seata-spring-boot-starter</artifactId>
      </exclusion>
   </exclusions>
</dependency>
<dependency>
   <groupId>io.seata</groupId>
   <artifactId>seata-spring-boot-starter</artifactId>
   <version>1.3.0</version>
</dependency>

二、引入kryo

这个是用来替换fastjson的，切记不要用fastjson,不然在序列化时候会各种报错

<!--kryo-->
<dependency>
   <groupId>com.esotericsoftware.kryo</groupId>
   <artifactId>kryo</artifactId>
   <version>2.24.0</version>
</dependency>
<dependency>
   <groupId>de.javakaffee</groupId>
   <artifactId>kryo-serializers</artifactId>
   <version>0.45</version>
</dependency>
<dependency>
   <groupId>com.esotericsoftware</groupId>
   <artifactId>kryo</artifactId>
   <version>4.0.2</version>
</dependency>

三、修改application.yml

seata:直接顶格写就行

seata:
  enabled: true
  application-id: ${spring.application.name}
  tx-service-group: my_test_tx_group
  enable-auto-data-source-proxy: true
  data-source-proxy-mode: AT
  use-jdk-proxy: false
  excludes-for-auto-proxying: firstClassNameForExclude,secondClassNameForExclude
  client:
    rm:
      async-commit-buffer-limit: 1000
      report-retry-count: 5
      table-meta-check-enable: false
      report-success-enable: false
      saga-branch-register-enable: false
      saga-json-parser: fastjson
      lock:
        retry-interval: 10
        retry-times: 30
        retry-policy-branch-rollback-on-conflict: true
    tm:
      commit-retry-count: 5
      rollback-retry-count: 5
      default-global-transaction-timeout: 60000
      degrade-check: false
      degrade-check-period: 2000
      degrade-check-allow-times: 10
    undo:
      data-validation: true
      log-serialization: kryo
      log-table: undo_log
      only-care-update-columns: true
    log:
      exceptionRate: 100
  service:
    vgroup-mapping:
      my_test_tx_group: wms_seata
    grouplist:
      default: 192.168.0.186:8091
    enable-degrade: false
    disable-global-transaction: false
  transport:
    shutdown:
      wait: 3
    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
      worker-thread-size: default
      boss-thread-size: 1
    type: TCP
    server: NIO
    heartbeat: true
    serialization: seata
    compressor: none
    enable-client-batch-send-request: true
  registry:
    type: consul
    load-balance: RandomLoadBalance
    load-balance-virtual-nodes: 10
    consul:
      server-addr: 192.168.1.66:8500

四、事务发起方添加 @GlobalTransactional

加了这个全局事务即可，其他微服务方法上无需加这个注解

@Override
@GlobalTransactional
public void test(){
   ...
}

这样就完成了seata的整合使用。

五、数据库新增表

建表sql 在码云上的seata项目中有, 路径 script/server/db

另外还少了一张表叫undo_log,这个可以自行网上查找建表sql,如果你的业务库有多个，就在每一个库里建一张。

六、启动seata服务端

首先就是下载seata的服务端 seata.io/zh-cn/blog/…  ，最好下载最新的版本1.3.0 +，不然对oracle的支持会有问题。

第二步修改配置文件。

seata 文件夹下有个conf文件夹，里面有 file.conf 和 registry.conf 这两个文件需要修改。我选择的是consul,所以其他没用部分就删除了。

registry.conf:

registry {
  # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
  type = "consul"

  consul {
    cluster = "test"  #这个可以自定义
    serverAddr = "192.168.1.66:8500"
  }

}

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

  file {
    name = "file.conf"
  }
}

file.conf：

service {
  #transaction service group mapping
  #修改，可不改,my_test_tx_group随便起名字。
  vgroupMapping.my_test_tx_group = "test"
  #only support when registry.type=file, please don't set multiple addresses
  # 此服务的地址
  default.grouplist = "192.168.0.186:8091"
  #disable seata
  disableGlobalTransaction = false
}

## transaction log store, only used in seata-server
store {
  ## store mode: file、db、redis
  mode = "db"

  ## file store property
  file {
    ## store location dir
    dir = "sessionStore"
    # branch session size , if exceeded first try compress lockkey, still exceeded throws exceptions
    maxBranchSessionSize = 16384
    # globe session size , if exceeded throws exceptions
    maxGlobalSessionSize = 512
    # file buffer size , if exceeded allocate new buffer
    fileWriteBufferCacheSize = 16384
    # when recover batch read size
    sessionReloadReadSize = 100
    # async, sync
    flushDiskMode = async
  }

  ## database store property
  db {
    ## the implement of javax.sql.DataSource, such as DruidDataSource(druid)/BasicDataSource(dbcp)/HikariDataSource(hikari) etc.
    datasource = "hikari"
    ## mysql/oracle/postgresql/h2/oceanbase etc.
    dbType = "oracle"
    driverClassName = "oracle.jdbc.driver.OracleDriver"
    url = "jdbc:oracle:thin:@//你的ip/数据库名"
    user = "root"
    password = "root"
    minConn = 5
    maxConn = 30
    globalTable = "GLOBAL_TABLE"
    branchTable = "BRANCH_TABLE"
    lockTable = "LOCK_TABLE"
    queryLimit = 100
    maxWait = 5000
  }

  ## redis store property
  redis {
    host = "192.168.1.66"
    port = "6379"
    password = ""
    database = "0"
    minConn = 1
    maxConn = 10
    queryLimit = 100
  }

}

接着启动他， windows 下直接bin目录下双击 bat文件

这样就可以使用seata的分布式事务啦，自己抛个异常看看数据回滚了没。

如果还有遇到问题可以给我留言哦。