Seata实现Sprincloud(Eureka+Feign)事务

目录

说明
步骤
实战

基本环境的配置
调用方和服务方的共同配置

事务的实现
拓展

说明

谨以此记录学习 Seata 时踩过的坑
项目是一个微服务的架构,需要使用到“分布式事务”,在折腾了tx-lcn、tcc-transaction等几个玩意儿后,最终把目光定格在seata上,决定用seata给基于Eureka+Feign的项目添加分布式事务管理。

资料如下:

步骤

  1. 下载、配置、运行 Seata Server
    Seata 需要使用 Server 端的配合来实现分布式事务,因此需要先部署 Seata 的 Server 环境。

  2. 配置共同环境
    服务的调用方以及服务提供方,都需要进行一些共同的、一致的配置。

  3. 配置各自的环境
    其实就是给服务调用方加上全局事务(分布式事务)的注解"@GlobalTransactional",服务提供方不需要额外配置。

实战

下载、配置并运行SeataServer

下载

下载地址:
http://seata.io/zh-cn/blog/download.html

Seata 1.2.0 (2020-04-20) 目录结构如下:

bin用于运行Seata Server; lib是server用到的资源库,无需理会; conf是配置文件目录。



bat为win下脚本文件; sh为unix-like系统下的脚本。



关注file.conf与register.conf

配置

根据自己需求修改配置文件—— "file.conf" 和 "registry.conf"。文章开头已贴出服务端以及应用端(客户端)配置项的说明的地址。

file.conf

此次需要用到数据库来保存 "undo_log" 等等的数据,需要在"file.conf"修改保存模式"mode"为"db",修改"db"中数据库相关的配置:

store {
  ## store mode: file、db
  mode = "db"

  ## database store property
  db {
    ## the implement of javax.sql.DataSource, such as DruidDataSource(druid)/BasicDataSource(dbcp) etc.
    datasource = "druid"
    ## mysql/oracle/postgresql/h2/oceanbase etc.
    dbType = "mysql"
    driverClassName = "com.mysql.jdbc.Driver"
    url = "jdbc:mysql://localhost:3306/seata_server"
    user = "root"
    password = "root"
    minConn = 5
    maxConn = 30
    globalTable = "global_table"
    branchTable = "branch_table"
    lockTable = "lock_table"
    queryLimit = 100
    maxWait = 5000
  }
}

mode = "db" 表明事务信息用db存储,当mode="db"时,只有db节点下的配置生效,不用管file节点

registry.conf

同样根据自己需求修改。
seata server会把自己注册到注册中心,像其它的微服务模块一样。registry.conf就是配置seata server使用何种注册中心以及如何注册。
registry节点为服务注册中心的类型及配置,此处选择type=eureka并修改对应的eureka的配置。

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

  eureka {
    serviceUrl = "http://localhost:8761/eureka"
    application = "default"
    weight = "1"
  }
}

#配置中心的配置,根据自己需求修改,eureka不支持充当配置中心,保留默认值
config {
  # file、nacos 、apollo、zk、consul、etcd3
  ...
  ...
}

运行

根据操作系统类型选择脚本运行。

基本环境的配置

由于此处使用数据库存储事务相关的数据,所以应先建库、建表。sql如下:

-- -------------------------------- 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(6),
    `gmt_modified`      DATETIME(6),
    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;

seata github直达

调用方和服务方的共同配置

数据库

以上是基本的数据表。另外,每个被调用的服务以及服务的调用方都需要用到 "undo_log"表用于事务的回滚,sql如下:

-- 注意此处0.3.0+ 增加唯一索引 ux_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;

maven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>1.2.0</version>
</dependency>

其它的配置文件


需要在resource目录下创建 "file.conf" 和 "registry.conf" 文件。这两个文件与之前下载的seata目录里面的配置文件不是一样的,两者内容如下:
file.conf

transport {
  # tcp udt unix-domain-socket
  type = "TCP"
  #NIO NATIVE
  server = "NIO"
  #enable heartbeat
  heartbeat = true
  # the client batch send request enable
  enableClientBatchSendRequest = true
  #thread factory for netty
  threadFactory {
    bossThreadPrefix = "NettyBoss"
    workerThreadPrefix = "NettyServerNIOWorker"
    serverExecutorThread-prefix = "NettyServerBizHandler"
    shareBossWorker = false
    clientSelectorThreadPrefix = "NettyClientSelector"
    clientSelectorThreadSize = 1
    clientWorkerThreadPrefix = "NettyClientWorkerThread"
    # netty boss thread size,will not be used for UDT
    bossThreadSize = 1
    #auto default pin or 8
    workerThreadSize = "default"
  }
  shutdown {
    # when destroy server, wait seconds
    wait = 3
  }
  serialization = "seata"
  compressor = "none"
}
service {
  #transaction service group mapping
  vgroupMapping.my_test_tx_group = "default"
  #only support when registry.type=file, please don't set multiple addresses
  #关于grouplist,只有当registry.type=file,注册中心是file方式时,才会起作用。 https://blog.csdn.net/weixin_39800144/article/details/100726116
  default.grouplist = "127.0.0.1:8091"
  #degrade, current not support
  enableDegrade = false
  #disable seata
  disableGlobalTransaction = false
}

client {
  rm {
    asyncCommitBufferLimit = 10000
    lock {
      retryInterval = 10
      retryTimes = 30
      retryPolicyBranchRollbackOnConflict = true
    }
    reportRetryCount = 5
    tableMetaCheckEnable = false
    reportSuccessEnable = false
  }
  tm {
    commitRetryCount = 5
    rollbackRetryCount = 5
  }
  undo {
    dataValidation = true
    logSerialization = "jackson"
    logTable = "undo_log"
  }
  log {
    exceptionRate = 100
  }
}

registry.conf:

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

  nacos {
    serverAddr = "localhost"
    namespace = ""
    cluster = "default"
  }
  eureka {
    serviceUrl = "http://localhost:8761/eureka"
    application = "default"
    weight = "1"
  }
  redis {
    serverAddr = "localhost:6379"
    db = "0"
    password = ""
    cluster = "default"
    timeout = "0"
  }
  zk {
    cluster = "default"
    serverAddr = "127.0.0.1:2181"
    session.timeout = 6000
    connect.timeout = 2000
    username = ""
    password = ""
  }
  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、springCloudConfig
  type = "file"

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

可根据自己需求修改,一般情况下默认值即可。
参考:

application.yml的配置

application.yml:

spring:
  cloud:
    alibaba:
      seata:
        tx-service-group: my_test_tx_group
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/xx
    username: root
    password: root

启动类的配置

@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)

seata 需要使用代理的 DataSource, 因此不使用 DataSourceAutoConfiguration

事务的实现

基本的配置已经实现,被调用的服务的方法(即服务提供方的方法)不需要做额外的配置,只需要在调用方(即需要通过feign调用其它服务)的方法上添加 "@GlobalTransactional" 注解,如:

@GlobalTransactional(name = "fsp-create-order", rollbackFor = Exception.class)
public void createOrder(Param param){
    //通过feign调用其它服务
    accountFeign.checkAccount();
    productFeign.checkNum();
}

拓展


  在client端的配置文件"file.conf"中,可以看到如上的service节点,红框部分是事务组的名称,官方说该名称应该和Server中的配置保持一致,然而在1.2.0版本的seata server端的配置文件中找不到该配置项...所以此处保留了sample的名称,此时可以运行成功。seata的文档真是一言难尽...
  项目是使用eureka作为注册中心,而在文章开头也提到对seata配置文件registry.conf的修改,把type改为"eureka",即把seata server注册到eureka中,此时,"vgroupMapping.my_test_tx_group"的值"default",就是seata server在eureka中的Application name:

参考:

posted @ 2020-07-01 00:41  LifeOfCoding  阅读(3685)  评论(0编辑  收藏  举报