一、简介

Seata 是一款开源的分布式事务解决方案，致力于提供高性能和简单易用的分布式事务服务。Seata 将为用户提供了 AT、TCC、SAGA 和 XA 事务模式，为用户打造一站式的分布式解决方案。
在这里插入图片描述

二、下载

Seata官方文档：https://seata.io/zh-cn/docs/overview/what-is-seata.html
Seata-Service官方下载地址：https://seata.io/zh-cn/blog/download.html

三、安装部署

大体可分为两大步骤：

1、service端配置

（1） 创建名为seata的数据库，执行以下脚本创建表，其他数据库类型脚本请点击这里

-- -------------------------------- 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_status_gmt_modified` (`status` , `gmt_modified`),
	KEY `idx_transaction_id` (`transaction_id`)
) ENGINE = InnoDB DEFAULT CHARSET = utf8mb4;

-- 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 = utf8mb4;

-- the table to store lock data

CREATE TABLE IF NOT EXISTS `lock_table`

(
	`row_key` VARCHAR(128) NOT NULL,
	`xid` VARCHAR(128),
	`transaction_id` BIGINT,
	`branch_id` BIGINT NOT NULL,
	`resource_id` VARCHAR(256),
	`table_name` VARCHAR(32),
	`pk` VARCHAR(36),
	`status` TINYINT NOT NULL DEFAULT '0' COMMENT '0:locked ,1:rollbacking',
	`gmt_create` DATETIME,
	`gmt_modified` DATETIME,
	PRIMARY KEY (`row_key`),
	KEY `idx_status` (`status`),	
	KEY `idx_branch_id` (`branch_id`)
) ENGINE = InnoDB DEFAULT CHARSET = utf8mb4;

CREATE TABLE IF NOT EXISTS `distributed_lock`
(
	`lock_key` CHAR(20) NOT NULL,
	`lock_value` VARCHAR(20) NOT NULL,
	`expire` BIGINT,
	primary key (`lock_key`)
) ENGINE = InnoDB DEFAULT CHARSET = utf8mb4;

INSERT INTO `distributed_lock` (lock_key, lock_value, expire) VALUES ('HandleAllSession', ' ', 0);

（2）修改conf目录下的file.conf文件，mode选择为db，然后配置db的数据库连接（即刚刚创建的seata数据库）

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

  ## database store property
  db {
    ## the implement of javax.sql.DataSource, such as DruidDataSource(druid)/BasicDataSource(dbcp)/HikariDataSource(hikari) etc.
    datasource = "druid"
    ## mysql/oracle/postgresql/h2/oceanbase etc.
    dbType = "mysql"
    driverClassName = "com.mysql.jdbc.Driver"
    ## if using mysql to store the data, recommend add rewriteBatchedStatements=true in jdbc connection param
    url = "jdbc:mysql://127.0.0.1:3306/seata?rewriteBatchedStatements=true"
    user = "root"
    password = "root"
    minConn = 5
    maxConn = 100
    globalTable = "global_table"
    branchTable = "branch_table"
    lockTable = "lock_table"
    queryLimit = 100
    maxWait = 5000
  }
}

server{
    vgroup_mapping.my_test_tx_group = "default"
    default.grouplist = "127.0.0.1:8091"
}

（3）修改conf目录下的registry.conf文件，这里我的seata注册和配置都选择nacos

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


  nacos {
    application = "seata-server"
    serverAddr = "127.0.0.1:8848"
    group = "DEFAULT_GROUP"
    namespace = "public"
    cluster = "default"
    username = "nacos"
    password = "nacos"
  }
}

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

  file {
    name = "file.conf"
  }
}

（3）使用bin目录下相应脚本启动seata-service

2、Client端配置

（1）在每个涉及到分布式事务的数据库中创建undo_log表，其他数据库类型请查看这里

-- for AT mode you must to init this sql for you business database. the seata server not need it.
CREATE TABLE IF NOT EXISTS `undo_log`
(
	`branch_id` BIGINT NOT NULL COMMENT 'branch transaction id',
	`xid` VARCHAR(128) NOT NULL COMMENT 'global transaction id',
	`context` VARCHAR(128) NOT NULL COMMENT 'undo_log context,such as serialization',
	`rollback_info` LONGBLOB NOT NULL COMMENT 'rollback info',
	`log_status` INT(11) NOT NULL COMMENT '0:normal status,1:defense status',
	`log_created` DATETIME(6) NOT NULL COMMENT 'create datetime',
	`log_modified` DATETIME(6) NOT NULL COMMENT 'modify datetime',
	UNIQUE KEY `ux_undo_log` (`xid`, `branch_id`)
) ENGINE = InnoDB AUTO_INCREMENT = 1
DEFAULT CHARSET = utf8mb4 COMMENT ='AT transaction mode undo table';

（2）服务中引入依赖，依赖版本最好对应你的seata-service客户端版本

<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
    <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>${对应你的seata-service版本}</version>
</dependency>

（3）配置所有有关服务的application.properties

#seata
seata.tx-service-group=my_test_tx_group

（4）application启动类添加@EnableAutoDataSourceProxy 注解，作用开启数据源代理

由于seata1.4.2版本可以新增了可以自动数据源代理，旧版的可能需要自己做数据源代理，这里就不细说了
（5）在分布式事务代码处使用@GlobalTransactional 注解开启全局事务

SpringCloud微服务之seata篇（一）

一、 简介

二、下载

三、安装部署

1、service端配置

2、Client端配置

一、简介