8.Seata实习分布式事务控制

seata介绍

Seata实习分布式事务控制

下载seata

修改registry.conf文件

注意：命令空间的一致

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

  nacos {
    serverAddr = "localhost"
    namespace = "public"
    cluster = "default"
  }
}

config {
  # file、nacos 、apollo、zk、consul、etcd3
  type = "nacos"
  nacos {
    serverAddr = "localhost"
    namespace = "public"
    cluster = "default"
  }
}

修改nacos-conf.txt

初始化seata在nacos的配置

安装git

cd conf
sh nacos-config.sh

1.4.0版本有下列配置参数，当前使用0.9.0版本

sh nacos-config.sh -h localhost -p 8848 -g SEATA_GROUP -t cbf85741-7e38-4644-b333-140733a87e51 -u nacos -w nacos

-h -p 指定nacos的端口地址；-g 指定配置的分组，注意，是配置的分组；-t 指定命名空间id； -u -w指定nacos的用户名和密码，同样，这里开启了nacos注册和配置认证的才需要指定。

nacos出现新配置

启动seata服务

cd bin
seata-server.bat -p 9000 -h 127.0.0.1 -m file

-h 指定运行的ip，本地运行也要指定，否则连接不上

nacos出现新服务

简单使用

建表存储日志

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;

添加依赖

<!--seata-->
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-seata</artifactId>
</dependency>
 <!--nacos客户端-->
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>
<dependency>
    <groupId>com.alibaba.nacos</groupId>
    <artifactId>nacos-client</artifactId>
    <version>1.1.3</version>
</dependency>
<!--nacos conf-->
<dependency>
    <groupId>com.alibaba.cloud</groupId>
    <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId>
</dependency>

DataSourceProxyConfig

Seata是通过代理数据源实现事务分支的，且是@Primary默认的数据源，否则事务不会回滚

@Configuration
public class DataSourceProxyConfig {
    @Bean
    @ConfigurationProperties(prefix = "spring.datasource")
    public DruidDataSource druidDataSource() {
        return new DruidDataSource();
    }

    @Primary
    @Bean
    public DataSourceProxy dataSource(DruidDataSource druidDataSource) {
        return new DataSourceProxy(druidDataSource);
    }
}

在resources下添加Seata的配置文件registry.conf

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

  nacos {
    serverAddr = "localhost"
    namespace = "public"
    cluster = "default"
  }
}

config {
  # file、nacos 、apollo、zk、consul、etcd3
  type = "nacos"
  nacos {
    serverAddr = "localhost"
    namespace = "public"
    cluster = "default"
  }
}

修改配置

tx-service-group 要与nacos-conf.txt的一致

spring:
  cloud:
    nacos:
      discovery:
        server-addr: localhost:8848
      config:
        server-addr: localhost:8848
        namespace: seata
        group: SEATA_GROUP
    alibaba:
      seata:
        tx-service-group: product-service

在需要的服务添加注解

  //全局事务控制
    @GlobalTransactional
    public Order createOrder(Long pid){
        //直接根据服务id获取服务
        Product product = productFeignClient.findByPid(pid);
        log.info("查询{}号商品:{}", pid, JSON.toJSONString(product));
        pre.cg.entity.Order order = new pre.cg.entity.Order().setNumber(1).setPid(pid).setUid(1L);
        log.info("订单信息{}", order.toString());
        orderDao.save(order);

        //扣库存
        productFeignClient.reduceInventory(pid,1);

        //mq发送
        rocketMQTemplate.convertAndSend("order-topic",order);

        return order;
    }

运行时可在数据库看到记录，运行结束后自动删除