前言

在微服务的大环境下，服务按照业务维度拆分之后会遇到事务不一致问题，Seata的开源填补了两阶段提交这种模式，并且无业务代码的侵入，这里采用eureka集群整合Seata。

一、Seata配置

1.1、Seata下载

下载Seata服务端压缩包：https://github.com/seata/seata/releases

1.2、修改conf目录中 flie.conf 文件

修改事务日志存储模式为 db 及数据库连接信息，且新增service模块，如下：

store {
  ## store mode: file、db、redis
  ## 使用数据库
  mode = "db"
  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.cj.jdbc.Driver"
    ## 数据库地址
    url = "jdbc:mysql://localhost:3306/seata?useUnicode=true&allowPublicKeyRetrieval=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT%2b8"
    ## 数据库账号
    user = "root"
    ## 数据库密码	
    password = "123456"
    minConn = 5
    maxConn = 100
    globalTable = "global_table"
    branchTable = "branch_table"
    lockTable = "lock_table"
    queryLimit = 100
    maxWait = 5000
  }

}

1.3、修改conf目录中 registry.conf文件

registry {
  type = "eureka"
  eureka {
    serviceUrl = "http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/"	#改成自己的eureka注册中心地址
    application = "seata-server"					#本客户端注册到eureka的微服务名称
    weight = "1"
  }
}

1.4、初始化seata数据库

由于我们使用了db模式存储事务日志，所以我们需要创建一个seata数据库，Seata数据库表初始化脚本：

-- -------------------------------- 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`),
    KEY `idx_xid` (`xid`)
) 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 ('AsyncCommitting', ' ', 0);
INSERT INTO `distributed_lock` (lock_key, lock_value, expire) VALUES ('RetryCommitting', ' ', 0);
INSERT INTO `distributed_lock` (lock_key, lock_value, expire) VALUES ('RetryRollbacking', ' ', 0);
INSERT INTO `distributed_lock` (lock_key, lock_value, expire) VALUES ('TxTimeoutCheck', ' ', 0);

二、微服务整合Seata

2.1、父工程项目创建

引入依赖

<!-- SpringBoot 依赖配置 -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-dependencies</artifactId>
    <version>2.3.7.RELEASE</version>
    <type>pom</type>
    <scope>import</scope>
</dependency>
<!-- Springcloud 依赖配置 -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-dependencies</artifactId>
    <version>Hoxton.SR9</version>
    <type>pom</type>
    <scope>import</scope>
</dependency>
<dependency>
   <groupId>mysql</groupId>
   <artifactId>mysql-connector-java</artifactId>
   <version>8.0.28</version>
</dependency>
<dependency>
   <groupId>com.alibaba</groupId>
   <artifactId>druid-spring-boot-starter</artifactId>
   <version>1.2.4</version>
</dependency>

<!--seata依赖-->
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
    <version>2021.1</version>
    <exclusions>
        <!--版本较低，1.3.0，因此排除-->
        <exclusion>
            <artifactId>seata-spring-boot-starter</artifactId>
            <groupId>io.seata</groupId>
        </exclusion>
    </exclusions>
</dependency>
<dependency>
    <groupId>io.seata</groupId>
    <artifactId>seata-spring-boot-starter</artifactId>
    <version>1.4.1</version>
</dependency>

2.2、Eureka集群搭建

2.3、搭建账户微服务

2.3.1 新建seata-account-service微服务

2.3.2引入依赖