文章目录
- 一、分布式事务存在的问题
- 二、分布式事务理论
- 三、认识Seata
- Seata分布式事务解决方案
- 1、XA模式
- 2、AT模式
- 3、SAGA模式
- 4.SAGA模式优缺点:
- 5.四种模式对比
- 四、微服务整合Seata AT案例
- Seata配置
- 微服务整合
- 2.1、父工程项目创建
- 引入依赖
- 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
- 2.3.3seata事务用到的表
- 2.3.4seata微服务配置
- 2.3.5yml配置seata事务
- 2.3.6数据源交给seata去代理
- 2.3.7主启动类去掉默认自动加载数据源
- 2.3.8业务数据
- db
- DO
- dao
- service
- mapper.xml
- controller
- 2.4、搭建库存微服务
- 2.4.1 新建seata-storage-service微服务
- 2.4.2引入依赖
- 2.4.3seata事务用到的表
- 2.4.4seata微服务配置
- 2.4.5yml配置seata事务
- 2.4.6数据源交给seata去代理
- 2.4.7主启动类去掉默认自动加载数据源
- 2.4.8业务数据
- db
- DO
- dao
- service
- mapper.xml
- controller
- 2.5、搭建订单微服务
- 2.5.1 新建seata-order-service微服务
- 2.5.2引入依赖
- 2.5.3seata事务用到的表
- 2.5.4seata微服务配置
- 2.5.5yml配置seata事务
- 2.5.6数据源交给seata去代理
- 2.5.7主启动类去掉默认自动加载数据源
- 2.5.8业务数据
- db
- DO
- dao
- service
- service实现类添加@GlobalTransactional
- mapper.xml
- fegin
- controller
- 2.6、测试
一、分布式事务存在的问题
在分布式系统下,一个业务跨越多个服务或数据源,每个服务都是一个分支事务,要保证所有分支事务最终状态一致,这样的事务就是分布式事务。
二、分布式事务理论
、CAP定理
CAP是指:Consistency(一致性)Availability(可用性)Partition tolerance(分区容错性)
1、一致性
用户访问分布式系统中的任意节点,得到的数据必须是一致的。
节点1的数据一旦发生修改,节点2的数据必须进行同步,与节点1的数据保持一致。
2、可用性
用户访问集群中的任意健康节点时,必须能得到响应,而不是超时或者拒绝。
当节点3发生故障时,就会对请求进行阻塞或者拒绝,此时节点3就是不可用的。
3、分区容错性
分区:因为网络故障或其它原因导致分布式系统中的部分系欸DNA与其它节点失去连接,形成独立分区。
容错:在集群出现分区时,整个系统也要持续对外提供服务。
起初节点1、2、3是互相连接的,即任意节点数据发生变化,其余两个节点的数据也将进行同步修改,但是假设节点3与其他两个节点的网络连接断开了,但是节点本身并没有故障,就会形成新的分区,此时一旦有人对节点2的数据进行了修改,并将修改信息同步到了节点1,此时用户访问不同的节点,假设访问节点1之后我们又访问了节点3,此时拿到的结果就是不一致的。此时就不满足一致性,如果我们非要满足一致性,我们怎么办?让节点3进入短暂的禁止访问状态,等待和节点2的网络通信回复,在此期间对于到来的一切请求都进行拒绝或者阻塞,这样一来确实一致性问题得到了解决,但是我们又说了可用性,即系统健康时就必须对请求做出响应,此时我们的节点3只是和其余两个节点不通,并没有不健康,所以这就是一种悖论,我们只能在一致性和可用性之间做出抉择!
CAP定理的主要内容:分布式系统节点通过网络连接,一定会出现分区问题(P)当分区出现时,系统的一致性(C)和可用性(A)就无法同时满足
CP:保证了系统的一致性,但是牺牲了系统的可用性。
AP:保证了系统的可用性,但是牺牲了系统的一致性。
BASE理论
BASE理论是对CAP的一种解决思路,包含三个思想:Basically Available (基本可用):分布式系统在出现故障时,允许损失部分可用性,即保证核心可用。Soft State(软状态):在一定时间内,允许出现中间状态,比如临时的不一致状态。Eventually Consistent(最终一致性):虽然无法保证强一致性,但是在软状态结束后,最终达到数据一致。
而分布式事务最大的问题是各个子事务的一致性问题,因此可以借鉴CAP定理和BASE理论:
AP模式:各子事务分别执行和提交,允许出现结果不一致(软状态),然后采用弥补措施恢复数据即可,实现最终一致。
CP模式:各个子事务执行后互相等待,同时提交,同时回滚,达成强一致。但事务等待过程中,处于弱可用状态。
解决分布式事务,各个子系统之间必须能感知到彼此的事务状态,才能保证状态一致,因此需要一个事务协调者来协调每一个事务的参与者(子系统事务)。 这里的子系统事务,称为分支事务;有关联的各个分支事务在一起称为全局事务。
三、认识Seata
Seata事务管理中有三个重要的角色:
TC (Transaction Coordinator) - 事务协调者:维护全局和分支事务的状态,协调全局事务提交或回滚。
TM (Transaction Manager) - 事务管理器:定义全局事务的范围、开始全局事务、提交或回滚全局事务。
RM (Resource Manager) - 资源管理器:管理分支事务处理的资源,与TC交谈以注册分支事务和报告分支事务的状态,并驱动分支事务提交或回滚。
Seata分布式事务解决方案
Seata提供了四种不同的分布式事务解决方案:XA模式:强一致性分阶段事务模式,牺牲了一定的可用性,无业务侵入TCC模式:最终一致的分阶段事务模式,有业务侵入AT模式:最终一致的分阶段事务模式,无业务侵入,也是Seata的默认模式SAGA模式:长事务模式,有业务侵入
1、XA模式
XA 规范 是 X/Open 组织定义的分布式事务处理(DTP,Distributed Transaction Processing)标准,XA 规范 描述了全局的TM与局部的RM之间的接口,几乎所有主流的数据库都对 XA 规范 提供了支持。
XA是规范,目前主流的数据库都实现了这种规范,实现的原理都是基于两阶段提交。
正常情况:
异常情况:
一阶段:
事务协调者通知每个事务参与者分别执行本地事务
本地事务执行完成后向事务协调者告知事务的执行状态,此时本地事务并没有提交,继续持有数据库锁
二阶段:
事务协调者根据一阶段的报告判断下一步操作①、如果一阶段所有分支事务都执行成功,则告知所有事务参与者提交事务。②、如果一阶段任意一个事务失败,则告知所有事务参与者回滚事务。
下面我们来看看Seata当中的XA模型:
RM一阶段的工作:
注册分支事务到TC
执行分支业务sql但不提交
报告执行状态给TC
TC二阶段的工作:
TC检测各分支事务的执行状态a.如果都成功,通知所有RM提交事务b.如果有失败,通知所有RM回滚事务
RM二阶段的工作:
接收TC的指令,提交或回滚事务。
XA模式的优缺点:
优点:事务的强一致性,满足ACID原则。常用数据库都支持,实现简单,并且没有代码侵入。缺点:因为一阶段需要锁定数据库资源,等待二阶段结束才会释放,性能较差。依赖关系型数据库实现事务。
如何利用Seata实现XA模式:
1、修改配置文件(每个参与事务的微服务),开启XA模式
seata:data-source-proxy-mode: XA
2、给发起全局事务的入口方法添加@GlobalTransactional注解
3、重启服务测试
2、AT模式
AT模式是对XA模式的弊端进行了完善(执行事务完并不会持续占有数据库资源)。我们来看看AT模式具体是怎么做的:
在XA模式当中,一阶段分支事务执行完事务后会等待TC的通知进行事务的提交或者事务的回滚,等待过程中会持有DB锁防止其他事务进行操作,这样会大大降低性能,在AT模式下,分支事务不需要等待TC的通知即可提交事务,但是会生成一份数据快照(undo_log),该快照记录了数据修改前和修改后的值,当TC通知分支事务进行事务提交或者回滚时,如果是提交,分支事务则仅需要删除生成的快照即可,如果是回滚,则需要根据快照当中的信息恢复数据。
AT模式下,该分支事务的执行流程如下:
一阶段:
1)TM发起并注册全局事务到TC
2)TM调用分支事务
3)分支事务准备执行业务SQL
4)RM拦截业务SQL,根据where条件查询原始数据,形成快照
5)RM执行业务SQL,提交本地事务,释放DB锁,此时money=90
6)RM报告本地事务状态给TC
二阶段:
1)TM通知TC事务结束
2)TC检查分支事务状态
a)都成功,则通知RM删除快照
b)有失败,通知RM根据快照恢复数据
流程图:
XA模式与AT模式的区别:
XA模式一阶段不提交事务,锁定资源;AT模式一阶段直接提交,不锁定资源。
XA模式依赖数据库机制实现回滚;AT模式利用数据快照实现数据回滚。
XA模式强一致;AT模式最终一致
AT模式的弊端——脏写问题
解决方案就是引入全局锁的概念,在释放DB锁之前,先要拿到全局锁,避免同一时刻有另外一个事务来操作当前持有的数据。
这个全局锁就限制了哪个事务可以操作该数据,当事务1执行业务SQL前,会先获取全局锁,TC就会进行记录,此时事务1释放DB锁去等待TC的通知(删除快照或根据快照修复数据),事务2拿到了DB锁开始执行业务SQL,当事务2尝试获取全局锁时,就会发现获取不到,因为全局锁现在被事务1所持有,此时假设恰好TC告知事务1进行数据回滚,事务1则会重新获取DB锁,但是DB锁此时被事务2所持有,这样就形成了死锁,怎么办?事务2在尝试获取一段时间全局锁后一直拿不到,就会放弃获取全局锁,此时事务1就拿到了DB锁,进行快照修复即可。前提是两个事务均是由seata控制的事务才会这样。假设事务2不是由seata控制的事务将会是怎样的?
我们上面说过,事务1记录undo_log时会记录数据修改前后的值,当我们进行数据恢复时,发现money此时为80,此时需要我们进行报警处理,人工的根据undo_log当中的数据进行数据恢复。
AT模式的优点:一阶段完成直接提交事务,释放数据库资源,性能比较好利用全局锁实现读写隔离没有代码侵入,框架自动完成回滚和提交
AT模式的缺点:两阶段之间属于软状态,属于最终一致框架的快照功能会影响性能,但比XA模式要好很多
3、TCC模式
TCC模式与AT模式非常相似,每阶段都是独立事务,区别在于TCC是通过人工代码控制来实现数据恢复,需要实现三个方法:
Try:资源的检测和预留。
Confirm:完成资源操作业务;要求 Try 成功 Confirm 一定要能成功。
Cancel:预留资源释放,可以理解为try的反向操作。
举例:一个扣减用户余额的业务。假设账户A原来余额是100,需要余额扣减30元。
阶段一( Try ):检查余额是否充足,如果充足则冻结金额增加30元,可用余额扣除30
初始余额:
此时,总金额 = 冻结金额 + 可用金额,数量依然是100不变。事务直接提交无需等待其它事务。
阶段二(Confirm):假如要提交(Confirm),则冻结金额扣减30
确认可以提交,不过之前可用金额已经扣减过了,这里只要清除冻结金额就好了:
此时,总金额 = 冻结金额 + 可用金额 = 0 + 70 = 70元
阶段二(Canncel):如果要回滚(Cancel),则冻结金额扣减30,可用余额增加30
需要回滚,那么就要释放冻结金额,恢复可用金额:
TCC模型:
可以看到,TCC模式和AT模式极其相似,但是区别在于,AT模式采用全局锁+undo_log的方式进行事务提交和回滚,这里我们不再使用锁,而是使用try-confirm-cancel的方式对操作进行记录。当TC通知分支事务可以提交的时候,分支事务直接执行confirm方法即可,通知回滚时则执行cancel方法
TCC模式的优缺点:
TCC模式的每个阶段是做什么的?
Try:资源检查和预留Confirm:业务执行和提交Cancel:预留资源的释放
TCC的优点是什么?
一阶段完成直接提交事务,释放数据库资源,性能好
相比AT模型,无需生成快照,无需使用全局锁,性能最强
不依赖数据库事务,而是依赖补偿操作,可以用于非事务型数据库
TCC的缺点是什么?
有代码侵入,需要人为编写try、Confirm和Cancel接口,太麻烦
软状态,事务是最终一致
需要考虑Confirm和Cancel的失败情况,做好幂等处理
TCC模式的两个重要问题:事务悬挂和空回滚
事务悬挂
对于已经空回滚的业务,之前被阻塞的try操作恢复,继续执行try,就永远不可能confirm或cancel ,事务一直处于中间状态,这就是业务悬挂。
执行try操作时,应当判断cancel是否已经执行过了,如果已经执行,应当阻止空回滚后的try操作,避免悬挂
空回滚
当某分支事务的try阶段阻塞时,可能导致全局事务超时而触发二阶段的cancel操作。在未执行try操作时先执行了cancel操作,这时cancel不能做回滚,就是空回滚。
执行cancel操作时,应当判断try是否已经执行,如果尚未执行,则应该空回
3、SAGA模式
原理:
在 Saga 模式下,分布式事务内有多个参与者,每一个参与者都是一个冲正补偿服务,需要用户根据业务场景实现其正向操作和逆向回滚操作。
分布式事务执行过程中,依次执行各参与者的正向操作,如果所有正向操作均执行成功,那么分布式事务提交。如果任何一个正向操作执行失败,那么分布式事务会去退回去执行前面各参与者的逆向回滚操作,回滚已提交的参与者,使分布式事务回到初始状态。
Saga也分为两个阶段:
一阶段:直接提交本地事务
二阶段:成功则什么都不做;失败则通过编写补偿业务来回滚
4.SAGA模式优缺点:
优点:
事务参与者可以基于事件驱动实现异步调用,吞吐高
一阶段直接提交事务,无锁,性能好
不用编写TCC中的三个阶段,实现简单
缺点:
软状态持续时间不确定,时效性差
没有锁,没有事务隔离,会有脏写
5.四种模式对比
四、微服务整合Seata AT案例
分布式事务和传统形式的事务区别有什么?众所周知,我们采用微服务框架开发项目时,不同服务之间通过相互调用的方式完成业务处理,用以下案例来描述分布式业务存在的问题:
假设我们此时现在有一个系统,其中包括下单系统、用户系统、仓库系统。当我们进行下单时,就需要创建订单信息,同时需要对用户的余额进行扣减,还需要对仓储系统的商品数量进行减少,由于每个系统分别负责一部分的业务,且其拥有独立的数据库信息,因此我们就会有三个事务,订单创建、余额扣减、商品剩余量扣减。
Seata配置
4.1.1Seata下载
下载Seata服务端压缩包:https://github.com/seata/seata/releases
4.1.2、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 = 5maxConn = 100globalTable = "global_table"branchTable = "branch_table"lockTable = "lock_table"queryLimit = 100maxWait = 5000}}
4.1.3、修改conf目录中 registry.conf文件
这里使用eureka注册中心
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"}
}
4.1.4、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 = InnoDBDEFAULT 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 = InnoDBDEFAULT 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 = InnoDBDEFAULT 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 = InnoDBDEFAULT 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);DROP TABLE IF EXISTS `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;
微服务整合
2.1、父工程项目创建
引入依赖
<?xml version="1.0" encoding="UTF-8"?><project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><groupId>com.my.springcloud</groupId><artifactId>cloud-seata</artifactId><version>1.0-SNAPSHOT</version><packaging>pom</packaging><modules><module>seata-account-service</module><module>seata-order-service</module><module>seata-storage-service</module><module>cloud-eureka-server7001</module><module>cloud-eureka-server7002</module><module>cloud-gateway-gateway</module></modules><!-- 统一管理jar包版本 --><properties><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding><maven.compiler.source>1.8</maven.compiler.source><maven.compiler.target>1.8</maven.compiler.target><junit.version>4.12</junit.version><log4j.version>1.2.17</log4j.version><lombok.version>1.16.18</lombok.version><mysql.version>8.0.28</mysql.version><druid.version>1.2.4</druid.version><mybatis.spring.boot.version>2.0.0</mybatis.spring.boot.version></properties><!-- 子模块继承之后,提供作用:锁定版本+子modlue不用写groupId和version --><dependencyManagement><dependencies><!--spring boot 2.3.2--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-dependencies</artifactId><version>2.3.2.RELEASE</version><type>pom</type><scope>import</scope></dependency><!--spring cloud Hoxton.SR9--><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-dependencies</artifactId><version>Hoxton.SR9</version><type>pom</type><scope>import</scope></dependency><!--spring cloud alibaba 2.2.5.RELEASE--><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-alibaba-dependencies</artifactId><version>2.2.5.RELEASE</version><type>pom</type><scope>import</scope></dependency><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId><version>${mybatis.spring.boot.version}</version></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><version>${mysql.version}</version></dependency><dependency><groupId>com.alibaba</groupId><artifactId>druid-spring-boot-starter</artifactId><version>${druid.version}</version></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>${lombok.version}</version><optional>true</optional></dependency><dependency><groupId>log4j</groupId><artifactId>log4j</artifactId><version>${log4j.version}</version></dependency><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>${junit.version}</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></dependencies></dependencyManagement><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId><configuration><addResources>true</addResources></configuration></plugin></plugins></build>
</project>
2.2、Eureka集群搭建
eureka搭建 添加链接描述
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
<dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-client</artifactId></dependency><!--seata依赖--><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-seata</artifactId><exclusions><exclusion><artifactId>seata-all</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><!--feign--><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-openfeign</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId></dependency><dependency><groupId>com.alibaba</groupId><artifactId>druid-spring-boot-starter</artifactId></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency></dependencies>
2.3.3seata事务用到的表
DROP TABLE IF EXISTS `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;
2.3.4seata微服务配置
在resources 下 新增2个配置文件 , file.conf 和 registry.conf
file.conf
transport {# tcp udt unix-domain-sockettype = "TCP"#NIO NATIVEserver = "NIO"#enable heartbeatheartbeat = true# the client batch send request enableenableClientBatchSendRequest = true#thread factory for nettythreadFactory {bossThreadPrefix = "NettyBoss"workerThreadPrefix = "NettyServerNIOWorker"serverExecutorThread-prefix = "NettyServerBizHandler"shareBossWorker = falseclientSelectorThreadPrefix = "NettyClientSelector"clientSelectorThreadSize = 1clientWorkerThreadPrefix = "NettyClientWorkerThread"# netty boss thread size,will not be used for UDTbossThreadSize = 1#auto default pin or 8workerThreadSize = "default"}shutdown {# when destroy server, wait secondswait = 3}serialization = "seata"compressor = "none"
}
service {#这里注意,等号前后都是配置,前面是yml里配置的事务组,后面是register.conf里定义的seata-servervgroupMapping.my_test_tx_group = "seata-server"#only support when registry.type=file, please don"t set multiple addressesseata_tc_server.grouplist = "127.0.0.1:8091"#degrade, current not supportenableDegrade = false#disable seatadisableGlobalTransaction = false
}
client {rm {asyncCommitBufferLimit = 10000lock {retryInterval = 10retryTimes = 30retryPolicyBranchRollbackOnConflict = true}reportRetryCount = 5tableMetaCheckEnable = falsereportSuccessEnable = false}tm {commitRetryCount = 5rollbackRetryCount = 5}undo {dataValidation = truelogSerialization = "jackson"logTable = "undo_log"}log {exceptionRate = 100}
}
registry.conf
registry {# file 、nacos 、eureka、redis、zk、consul、etcd3、sofa## 注册中心为eurekatype = "eureka"loadBalance = "RandomLoadBalance"loadBalanceVirtualNodes = 10nacos {application = "seata-server"serverAddr = "127.0.0.1:8848"group = "SEATA_GROUP"namespace = ""cluster = "default"username = ""password = ""}eureka {## eureka地址serviceUrl = "http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/"application = "seata-server"weight = "1"}redis {serverAddr = "localhost:6379"db = 0password = "123456"cluster = "default"timeout = 0}zk {cluster = "default"serverAddr = "127.0.0.1:2181"sessionTimeout = 6000connectTimeout = 2000username = ""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、etcd3type = "file"nacos {serverAddr = "127.0.0.1:8848"namespace = ""group = "SEATA_GROUP"username = ""password = ""}consul {serverAddr = "127.0.0.1:8500"}apollo {appId = "seata-server"apolloMeta = "http://192.168.1.204:8801"namespace = "application"apolloAccesskeySecret = ""}zk {serverAddr = "127.0.0.1:2181"sessionTimeout = 6000connectTimeout = 2000username = ""password = ""}etcd3 {serverAddr = "http://localhost:2379"}file {name = "file.conf"}
}
2.3.5yml配置seata事务
需要在yml配置文件加上配置项,指明当前服务使用了 seata分布式事务组件,且需要加入的分布式事务组是哪个:
server:# 服务器的HTTP端口,默认为80port: 2000# Spring配置
spring:application:#微服务名称name: seata-account-servicedatasource:type: com.alibaba.druid.pool.DruidDataSource # 当前数据源操作类型driverClassName: com.mysql.cj.jdbc.Driver # mysql驱动包url: jdbc:mysql://localhost:3306/seata_account?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=true&serverTimezone=GMT%2B8 # 数据库名称username: rootpassword: 123456seata:enabled: trueapplication-id: ${spring.application.name}tx-service-group: seata-serverenable-auto-data-source-proxy: trueservice:default: 127.0.0.1:8091vgroup-mapping:seata-server: defaultconfig:type: filefile:name: file.confregistry:type: filefile:name: file# MyBatis
mybatis:# 所有Entity别名类所在包typeAliasesPackage: com.my.springcloud.domain# 配置mapper的扫描,找到所有的mapper.xml映射文件mapperLocations: classpath*:mapper/*Mapper.xml# 加载全局的配置文件# configLocation: classpath:mybatis/mybatis-config.xml# eureka客户端配置
eureka:client:#表示是否向Eureka注册中心注册自己register-with-eureka: truefetch-registry: true # false表示自己就是注册中心,我的职责就是维护服务实例,并不需要去检索服务service-url:#defaultZone: http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/defaultZone: http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/instance:#向注册中心注册服务IDinstance-id: ${spring.cloud.client.ip-address}:${server.port}prefer-ip-address: true #显示IP地址# Eureka客户端向服务端发送心跳的时间间隔,单位为秒(默认是30秒)lease-renewal-interval-in-seconds: 30#Eureka服务端在收到最后一次心跳后等待时间上限,单位为秒(默认是90秒),超时将剔除服务lease-expiration-duration-in-seconds: 90logging:level:io:seata: info
2.3.6数据源交给seata去代理
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.beans.factory.annotation.Value;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;import javax.sql.DataSource;/*** 使用Seata对数据源进行代理*/
@Configuration
public class DataSourceProxyConfig {//加载数据源@Bean@ConfigurationProperties(prefix = "spring.datasource")public DataSource druidDataSource() {return new DruidDataSource();}@Value("${mybatis.mapperLocations}")private String mapperLocations;@Beanpublic DataSource dataSourceProxy(DataSource dataSource) {return new DataSourceProxy(dataSource);}@Beanpublic SqlSessionFactory sqlSessionFactoryBean(DataSource dataSourceProxy) throws Exception {SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();sqlSessionFactoryBean.setDataSource(dataSourceProxy);sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(mapperLocations));sqlSessionFactoryBean.setTransactionFactory(new SpringManagedTransactionFactory());return sqlSessionFactoryBean.getObject();}}
2.3.7主启动类去掉默认自动加载数据源
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.cloud.netflix.eureka.EnableEurekaClient;
import org.springframework.cloud.openfeign.EnableFeignClients;@EnableEurekaClient //开启Eureka的客户端服务,将会自动注册到注册中心
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
public class SeataAccountApp {public static void main(String[] args) {SpringApplication.run(SeataAccountApp.class, args);}
}
2.3.8业务数据
db
(1)创建account数据库
(2)在数据库下创建seata_account表
DROP TABLE IF EXISTS `t_account`;
CREATE TABLE `t_account`
(`id` BIGINT(20) NOT NULL AUTO_INCREMENT comment '主键',`user_id` BIGINT(20) comment '用户id',`total` NUMERIC(20) comment '总额度',`used` NUMERIC(20) comment '已用额度',`residue` NUMERIC(20) comment '剩余额度',PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 comment '账户表';
DO
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Account {private Long id;/*** 用户id*/private Long userId;/*** 总额度*/private BigDecimal total;/*** 已用额度*/private BigDecimal used;/*** 剩余额度*/private BigDecimal residue;
}
dao
@Mapper
public interface AccountDao {/*** 扣减账户余额*/void decrease(@Param("userId") Long userId, @Param("money") BigDecimal money);
}
service
public interface AccountService {/*** 扣减账户余额* @param userId 用户id* @param money 金额*/void decrease(@RequestParam("userId") Long userId, @RequestParam("money") BigDecimal money);
}
mapper.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" ><mapper namespace="com.my.springcloud.dao.AccountDao"><resultMap id="BaseResultMap" type="com.my.springcloud.domain.Account"><id column="id" property="id" jdbcType="BIGINT"/><result column="user_id" property="userId" jdbcType="BIGINT"/><result column="total" property="total" jdbcType="DECIMAL"/><result column="used" property="used" jdbcType="DECIMAL"/><result column="residue" property="residue" jdbcType="DECIMAL"/></resultMap><update id="decrease">UPDATE t_accountSETresidue = residue - #{money},used = used + #{money}WHEREuser_id = #{userId};</update></mapper>
controller
public class AccountController {@ResourceAccountService accountService;/*** 扣减账户余额*/@RequestMapping("/account/decrease")public CommonResult decrease(@RequestParam("userId") Long userId, @RequestParam("money") BigDecimal money) {accountService.decrease(userId, money);return new CommonResult(200, "扣减账户余额成功!");}
}
2.4、搭建库存微服务
2.4.1 新建seata-storage-service微服务
2.4.2引入依赖
<dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-client</artifactId></dependency><!--seata依赖--><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-seata</artifactId><exclusions><exclusion><artifactId>seata-all</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><!--feign--><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-openfeign</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId></dependency><dependency><groupId>com.alibaba</groupId><artifactId>druid-spring-boot-starter</artifactId></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency></dependencies>
2.4.3seata事务用到的表
DROP TABLE IF EXISTS `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;
2.4.4seata微服务配置
在resources 下 新增2个配置文件 , file.conf 和 registry.conf
file.conf
transport {# tcp udt unix-domain-sockettype = "TCP"#NIO NATIVEserver = "NIO"#enable heartbeatheartbeat = true# the client batch send request enableenableClientBatchSendRequest = true#thread factory for nettythreadFactory {bossThreadPrefix = "NettyBoss"workerThreadPrefix = "NettyServerNIOWorker"serverExecutorThread-prefix = "NettyServerBizHandler"shareBossWorker = falseclientSelectorThreadPrefix = "NettyClientSelector"clientSelectorThreadSize = 1clientWorkerThreadPrefix = "NettyClientWorkerThread"# netty boss thread size,will not be used for UDTbossThreadSize = 1#auto default pin or 8workerThreadSize = "default"}shutdown {# when destroy server, wait secondswait = 3}serialization = "seata"compressor = "none"
}
service {#这里注意,等号前后都是配置,前面是yml里配置的事务组,后面是register.conf里定义的seata-servervgroupMapping.my_test_tx_group = "seata-server"#only support when registry.type=file, please don"t set multiple addressesseata_tc_server.grouplist = "127.0.0.1:8091"#degrade, current not supportenableDegrade = false#disable seatadisableGlobalTransaction = false
}
client {rm {asyncCommitBufferLimit = 10000lock {retryInterval = 10retryTimes = 30retryPolicyBranchRollbackOnConflict = true}reportRetryCount = 5tableMetaCheckEnable = falsereportSuccessEnable = false}tm {commitRetryCount = 5rollbackRetryCount = 5}undo {dataValidation = truelogSerialization = "jackson"logTable = "undo_log"}log {exceptionRate = 100}
}
registry.conf
registry {# file 、nacos 、eureka、redis、zk、consul、etcd3、sofa## 注册中心为eurekatype = "eureka"loadBalance = "RandomLoadBalance"loadBalanceVirtualNodes = 10nacos {application = "seata-server"serverAddr = "127.0.0.1:8848"group = "SEATA_GROUP"namespace = ""cluster = "default"username = ""password = ""}eureka {## eureka地址serviceUrl = "http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/"application = "seata-server"weight = "1"}redis {serverAddr = "localhost:6379"db = 0password = "123456"cluster = "default"timeout = 0}zk {cluster = "default"serverAddr = "127.0.0.1:2181"sessionTimeout = 6000connectTimeout = 2000username = ""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、etcd3type = "file"nacos {serverAddr = "127.0.0.1:8848"namespace = ""group = "SEATA_GROUP"username = ""password = ""}consul {serverAddr = "127.0.0.1:8500"}apollo {appId = "seata-server"apolloMeta = "http://192.168.1.204:8801"namespace = "application"apolloAccesskeySecret = ""}zk {serverAddr = "127.0.0.1:2181"sessionTimeout = 6000connectTimeout = 2000username = ""password = ""}etcd3 {serverAddr = "http://localhost:2379"}file {name = "file.conf"}
}
2.4.5yml配置seata事务
需要在yml配置文件加上配置项,指明当前服务使用了 seata分布式事务组件,且需要加入的分布式事务组是哪个:
server:# 服务器的HTTP端口,默认为80port: 2002#Spring配置
spring:application:name: seata-storage-service#----------------------------数据源----------------------------datasource:type: com.alibaba.druid.pool.DruidDataSourcedriverClassName: com.mysql.cj.jdbc.Driverurl: jdbc:mysql://localhost:3306/seata_storage?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=true&serverTimezone=GMT%2B8username: rootpassword: 123456druid:initial-size: 5min-idle: 5max-active: 20test-while-idle: truetest-on-borrow: falsetest-on-return: falsepool-prepared-statements: truemax-pool-prepared-statement-per-connection-size: 20max-wait: 60000time-between-eviction-runs-millis: 60000min-evictable-idle-time-millis: 30000filters: statasync-init: true#----------------------------seata----------------------------
seata:enabled: trueapplication-id: ${spring.application.name}tx-service-group: seata-serverenable-auto-data-source-proxy: trueservice:default: 127.0.0.1:8091vgroup-mapping:seata-server: defaultconfig:type: filefile:name: file.confregistry:type: filefile:name: file# eureka客户端配置
eureka:client:#表示是否向Eureka注册中心注册自己register-with-eureka: truefetch-registry: true # false表示自己就是注册中心,我的职责就是维护服务实例,并不需要去检索服务service-url:#defaultZone: http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/defaultZone: http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/instance:#向注册中心注册服务IDinstance-id: ${spring.cloud.client.ip-address}:${server.port}prefer-ip-address: true #显示IP地址# Eureka客户端向服务端发送心跳的时间间隔,单位为秒(默认是30秒)lease-renewal-interval-in-seconds: 30#Eureka服务端在收到最后一次心跳后等待时间上限,单位为秒(默认是90秒),超时将剔除服务lease-expiration-duration-in-seconds: 90#MyBatis
mybatis:#所有Entity别名类所在包,多个路径用逗号分割typeAliasesPackage: com.my.springcloud.domain# 配置mapper的扫描,找到所有的mapper,多个目录用逗号或者分号分隔mapperLocations: classpath*:mapper/*Mapper.xml# 加载全局的配置文件# configLocation: classpath:mybatis/mybatis-config.xml
2.4.6数据源交给seata去代理
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.beans.factory.annotation.Value;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;import javax.sql.DataSource;/*** 使用Seata对数据源进行代理*/
@Configuration
public class DataSourceProxyConfig {//加载数据源@Bean@ConfigurationProperties(prefix = "spring.datasource")public DataSource druidDataSource() {return new DruidDataSource();}@Value("${mybatis.mapperLocations}")private String mapperLocations;@Beanpublic DataSource dataSourceProxy(DataSource dataSource) {return new DataSourceProxy(dataSource);}@Beanpublic SqlSessionFactory sqlSessionFactoryBean(DataSource dataSourceProxy) throws Exception {SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();sqlSessionFactoryBean.setDataSource(dataSourceProxy);sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(mapperLocations));sqlSessionFactoryBean.setTransactionFactory(new SpringManagedTransactionFactory());return sqlSessionFactoryBean.getObject();}}
2.4.7主启动类去掉默认自动加载数据源
@EnableEurekaClient //开启Eureka的客户端服务,将会自动注册到注册中心
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
public class SeataStorageApp {public static void main(String[] args) {SpringApplication.run(SeataStorageApp.class, args);}
}
2.4.8业务数据
db
(1)创建storage数据库
(2)在数据库下创建seata_storage表
DROP TABLE IF EXISTS `t_storage`;
CREATE TABLE `t_storage`
(`id` bigint(20) NOT NULL AUTO_INCREMENT comment '主键',`product_id` bigint(30) comment '产品id',`total` INTEGER(20) comment '总库存',`used` INTEGER(20) comment '已用库存',`residue` INTEGER(30) comment '剩余库存',PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 comment '库存表';
DO
@Data
public class Storage {private Long id;/*** 产品id*/private Long productId;/*** 总库存*/private Integer total;/*** 已用库存*/private Integer used;/*** 剩余库存*/private Integer residue;
}
dao
@Mapper
public interface StorageDao {//扣减库存void decrease(@Param("productId") Long productId, @Param("count") Integer count);
}
service
public interface StorageService {/*** 扣减库存*/void decrease(Long productId, Integer count);
}
mapper.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.my.springcloud.dao.StorageDao"><resultMap id="BaseResultMap" type="com.my.springcloud.domain.Storage"><id column="id" property="id" jdbcType="BIGINT"/><result column="product_id" property="productId" jdbcType="BIGINT"/><result column="total" property="total" jdbcType="INTEGER"/><result column="used" property="used" jdbcType="INTEGER"/><result column="residue" property="residue" jdbcType="INTEGER"/></resultMap><update id="decrease">UPDATEt_storageSET used = used + #{count},residue = residue - #{count}WHERE product_id = #{productId}</update>
</mapper>
controller
@RestController
public class StorageController {@Autowiredprivate StorageService storageService;/*** 扣减库存*/@RequestMapping("/storage/decrease")public CommonResult decrease(Long productId, Integer count) {storageService.decrease(productId, count);return new CommonResult(200, "扣减库存成功!");}
}
2.5、搭建订单微服务
2.5.1 新建seata-order-service微服务
2.5.2引入依赖
<dependencies><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-netflix-eureka-client</artifactId></dependency><!--seata依赖--><dependency><groupId>com.alibaba.cloud</groupId><artifactId>spring-cloud-starter-alibaba-seata</artifactId><exclusions><exclusion><artifactId>seata-all</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><!--feign--><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter-openfeign</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId></dependency><dependency><groupId>com.alibaba</groupId><artifactId>druid-spring-boot-starter</artifactId></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><!-- 添加 httpclient 框架依赖 --><dependency><groupId>io.github.openfeign</groupId><artifactId>feign-httpclient</artifactId></dependency><dependency><groupId>io.github.openfeign</groupId><artifactId>feign-okhttp</artifactId></dependency></dependencies>
2.5.3seata事务用到的表
DROP TABLE IF EXISTS `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;
2.5.4seata微服务配置
在resources 下 新增2个配置文件 , file.conf 和 registry.conf
file.conf
transport {# tcp udt unix-domain-sockettype = "TCP"#NIO NATIVEserver = "NIO"#enable heartbeatheartbeat = true# the client batch send request enableenableClientBatchSendRequest = true#thread factory for nettythreadFactory {bossThreadPrefix = "NettyBoss"workerThreadPrefix = "NettyServerNIOWorker"serverExecutorThread-prefix = "NettyServerBizHandler"shareBossWorker = falseclientSelectorThreadPrefix = "NettyClientSelector"clientSelectorThreadSize = 1clientWorkerThreadPrefix = "NettyClientWorkerThread"# netty boss thread size,will not be used for UDTbossThreadSize = 1#auto default pin or 8workerThreadSize = "default"}shutdown {# when destroy server, wait secondswait = 3}serialization = "seata"compressor = "none"
}
service {#这里注意,等号前后都是配置,前面是yml里配置的事务组,后面是register.conf里定义的seata-servervgroupMapping.my_test_tx_group = "seata-server"#only support when registry.type=file, please don"t set multiple addressesseata_tc_server.grouplist = "127.0.0.1:8091"#degrade, current not supportenableDegrade = false#disable seatadisableGlobalTransaction = false
}
client {rm {asyncCommitBufferLimit = 10000lock {retryInterval = 10retryTimes = 30retryPolicyBranchRollbackOnConflict = true}reportRetryCount = 5tableMetaCheckEnable = falsereportSuccessEnable = false}tm {commitRetryCount = 5rollbackRetryCount = 5}undo {dataValidation = truelogSerialization = "jackson"logTable = "undo_log"}log {exceptionRate = 100}
}
registry.conf
registry {# file 、nacos 、eureka、redis、zk、consul、etcd3、sofa## 注册中心为eurekatype = "eureka"loadBalance = "RandomLoadBalance"loadBalanceVirtualNodes = 10nacos {application = "seata-server"serverAddr = "127.0.0.1:8848"group = "SEATA_GROUP"namespace = ""cluster = "default"username = ""password = ""}eureka {## eureka地址serviceUrl = "http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/"application = "seata-server"weight = "1"}redis {serverAddr = "localhost:6379"db = 0password = "123456"cluster = "default"timeout = 0}zk {cluster = "default"serverAddr = "127.0.0.1:2181"sessionTimeout = 6000connectTimeout = 2000username = ""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、etcd3type = "file"nacos {serverAddr = "127.0.0.1:8848"namespace = ""group = "SEATA_GROUP"username = ""password = ""}consul {serverAddr = "127.0.0.1:8500"}apollo {appId = "seata-server"apolloMeta = "http://192.168.1.204:8801"namespace = "application"apolloAccesskeySecret = ""}zk {serverAddr = "127.0.0.1:2181"sessionTimeout = 6000connectTimeout = 2000username = ""password = ""}etcd3 {serverAddr = "http://localhost:2379"}file {name = "file.conf"}
}
2.5.5yml配置seata事务
需要在yml配置文件加上配置项,指明当前服务使用了 seata分布式事务组件,且需要加入的分布式事务组是哪个:
server:# 服务器的HTTP端口,默认为80port: 2001#Spring配置
spring:application:name: seata-order-service#----------------------------数据源----------------------------datasource:type: com.alibaba.druid.pool.DruidDataSourcedriverClassName: com.mysql.cj.jdbc.Driverurl: jdbc:mysql://localhost:3306/seata_order?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&useSSL=true&serverTimezone=GMT%2B8username: rootpassword: 123456druid:initial-size: 5min-idle: 5max-active: 20test-while-idle: truetest-on-borrow: falsetest-on-return: falsepool-prepared-statements: truemax-pool-prepared-statement-per-connection-size: 20max-wait: 60000time-between-eviction-runs-millis: 60000min-evictable-idle-time-millis: 30000filters: statasync-init: true#----------------------------seata----------------------------
seata:enabled: trueapplication-id: ${spring.application.name}tx-service-group: seata-serverenable-auto-data-source-proxy: trueservice:default: 127.0.0.1:8091vgroup-mapping:seata-server: defaultconfig:type: filefile:name: file.confregistry:type: filefile:name: file# eureka客户端配置
eureka:client:#表示是否向Eureka注册中心注册自己register-with-eureka: truefetch-registry: true # false表示自己就是注册中心,我的职责就是维护服务实例,并不需要去检索服务service-url:#defaultZone: http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/defaultZone: http://eureka7001.com:7001/eureka/,http://eureka7002.com:7002/eureka/instance:#向注册中心注册服务IDinstance-id: ${spring.cloud.client.ip-address}:${server.port}prefer-ip-address: true #显示IP地址# Eureka客户端向服务端发送心跳的时间间隔,单位为秒(默认是30秒)lease-renewal-interval-in-seconds: 30#Eureka服务端在收到最后一次心跳后等待时间上限,单位为秒(默认是90秒),超时将剔除服务lease-expiration-duration-in-seconds: 90#MyBatis
mybatis:#所有Entity别名类所在包,多个路径用逗号分割typeAliasesPackage: com.my.springcloud.domain# 配置mapper的扫描,找到所有的mapper,多个目录用逗号或者分号分隔mapperLocations: classpath*:mapper/*Mapper.xml# 加载全局的配置文件# configLocation: classpath:mybatis/mybatis-config.xml# feign超时设置
feign:client:config:default: # default全局的配置loggerLevel: BASIC # 日志级别,BASIC就是基本的请求和响应信息httpclient:enabled: true # 开启feign对HttpClient的支持max-connections: 200 # 最大的连接数max-connections-per-route: 50 # 每个路径的最大连接数logging:level:io:seata: info
2.5.6数据源交给seata去代理
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.beans.factory.annotation.Value;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;import javax.sql.DataSource;/*** 使用Seata对数据源进行代理*/
@Configuration
public class DataSourceProxyConfig {//加载数据源@Bean@ConfigurationProperties(prefix = "spring.datasource")public DataSource druidDataSource() {return new DruidDataSource();}@Value("${mybatis.mapperLocations}")private String mapperLocations;@Beanpublic DataSource dataSourceProxy(DataSource dataSource) {return new DataSourceProxy(dataSource);}@Beanpublic SqlSessionFactory sqlSessionFactoryBean(DataSource dataSourceProxy) throws Exception {SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();sqlSessionFactoryBean.setDataSource(dataSourceProxy);sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(mapperLocations));sqlSessionFactoryBean.setTransactionFactory(new SpringManagedTransactionFactory());return sqlSessionFactoryBean.getObject();}}
2.5.7主启动类去掉默认自动加载数据源
@EnableFeignClients
@EnableEurekaClient //开启Eureka的客户端服务,将会自动注册到注册中心
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)//取消数据源的自动创建
public class SeataOrderApp {public static void main(String[] args) {SpringApplication.run(SeataOrderApp.class, args);}
}
2.5.8业务数据
db
(1)创建storage数据库
(2)在数据库下创建seata_storage表
DROP TABLE IF EXISTS `t_storage`;
CREATE TABLE `t_storage`
(`id` bigint(20) NOT NULL AUTO_INCREMENT comment '主键',`product_id` bigint(30) comment '产品id',`total` INTEGER(20) comment '总库存',`used` INTEGER(20) comment '已用库存',`residue` INTEGER(30) comment '剩余库存',PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8 comment '库存表';
DO
@Data
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Order {private Long id;private Long userId;private Long productId;private Integer count;private BigDecimal money;private Integer status; //订单状态:0:创建中;1:已完结
}
dao
@Mapper
public interface OrderDao {//1 新建订单void create(Order order);//2 修改订单状态,从零改为1void update(@Param("userId") Long userId, @Param("status") Integer status);
}
service
public interface OrderService {void create(Order order);
}
service实现类添加@GlobalTransactional
@Service
@Slf4j
public class OrderServiceImpl implements OrderService {@Resourceprivate OrderDao orderDao;@Resourceprivate StorageService storageService;@Resourceprivate AccountService accountService;/*** 创建订单->调用库存服务扣减库存->调用账户服务扣减账户余额->修改订单状态* 简单说:下订单->扣库存->减余额->改状态*/@Override@GlobalTransactional( rollbackFor = Exception.class)public void create(Order order) {log.info("----->开始新建订单");//1 新建订单orderDao.create(order);//2 扣减库存log.info("----->订单微服务开始调用库存,做扣减Count");storageService.decrease(order.getProductId(), order.getCount());log.info("----->订单微服务开始调用库存,做扣减end");//3 扣减账户log.info("----->订单微服务开始调用账户,做扣减Money");accountService.decrease(order.getUserId(), order.getMoney());log.info("----->订单微服务开始调用账户,做扣减end");//4 修改订单状态,从零到1,1代表已经完成log.info("----->修改订单状态开始");orderDao.update(order.getUserId(), 0);log.info("----->修改订单状态结束");log.info("----->下订单结束了,O(∩_∩)O哈哈~");}
}
mapper.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" ><mapper namespace="com.my.springcloud.dao.OrderDao"><resultMap id="BaseResultMap" type="com.my.springcloud.domain.Order"><id column="id" property="id" jdbcType="BIGINT"/><result column="user_id" property="userId" jdbcType="BIGINT"/><result column="product_id" property="productId" jdbcType="BIGINT"/><result column="count" property="count" jdbcType="INTEGER"/><result column="money" property="money" jdbcType="DECIMAL"/><result column="status" property="status" jdbcType="INTEGER"/></resultMap><insert id="create">insert into t_order (id, user_id, product_id, count, money, status)values (null, #{userId}, #{productId}, #{count}, #{money}, 0);</insert><update id="update">update t_orderset status = 1where user_id = #{userId}and status = #{status};</update>
</mapper>
fegin
@FeignClient(value = "seata-account-service")
public interface AccountService {@PostMapping(value = "/account/decrease")CommonResult decrease(@RequestParam("userId") Long userId, @RequestParam("money") BigDecimal money);
}
@FeignClient(value = "seata-storage-service")
public interface StorageService {@PostMapping(value = "/storage/decrease")CommonResult decrease(@RequestParam("productId") Long productId, @RequestParam("count") Integer count);
}
controller
@RestController
public class OrderController {@Resourceprivate OrderService orderService;@GetMapping("/order/create")public CommonResult create(Order order) {orderService.create(order);return new CommonResult(200, "订单创建成功");}
}
2.6、测试
启动eureka7001和7002
启动seata service
启动库存微服务,账户微服务,订单微服务
访问 http://localhost:2001/order/create
业务流程
1.创建订单
2 扣减库存
3 扣减账户
4 修改订单状态,从零到1,1代表已经完成
添加@GlobalTransactional注解开启seata事务
扣减账户的时候模拟异常
获得全局事务状态
// 开启全局事务地方获取全局事务xid
String xid = RootContext.getXID();
// 通过全局事务xid获得GlobalStatus枚举类
GlobalTransaction globalTransaction = GlobalTransactionContext.reload(xid);
GlobalStatus globalStatus = globalTransaction.getStatus();
// 通过GlobalStatus枚举类获取全局事务状态值
int code = globalStatus.getCode();
使用idea控制台获取全局事务id
查看数据库
查看数据库表数据已经回滚