21.cloudAlibaba-Seata处理分布式事务

1. 分布式事务问题

分布式前

单机单库没这个问题

分布式之后

一次业务操作需要跨多个数据源或需要跨多个系统进行远程调用，就会产生分布式事务问题

2. Seata简介

是什么

Seata是一款开源的分布式事务解决方案，致力于在微服务架构下提供高性能和简单易用的分布式事务服务

官网地址： http://seata.io/zh-cn/

能干嘛

分布式事务处理过程的-ID+三组件模型

1. Transaction ID XID 全局唯一的事务ID
2. Transaction Coordinator(TC)：事务协调器，维护全局事务的运行状态，负责协调并驱动全局事务的提交或回滚;
3. Transaction Manager(TM) ：控制全局事务的边界，负责开启一个全局事务，并最终发起全局提交或全局回滚的决议;
4. Resource Manager(RM) ：控制分支事务，负责分支注册，状态汇报，并接收事务协调器的指令，驱动分支（本地）事务的提交和回滚；

处理过程

去哪下：https://github.com/seata/seata/releases

怎么玩

本地@Transactional

全局@GlobalTransactional

SEATA的分布式交易解决方案

3. Seata-Server安装

1.官网地址：http://seata.io/zh-cn/

2.下载版本（我选择的0.9）

3.seata-server-0.9.0.zip解压到指定目录并修改conf目录下的file.conf配置文件

先备份原始file.conf文件

主要修改：自定义事务组名称+事务日志存储模式为db+数据库连接信息

service模块

vgroup_mapping.my_test_tx_group = "fsp_tx_group"

store模块

mode = "db"
 
  url = "jdbc:mysql://127.0.0.1:3306/seata"
  user = "root"
  password = "你自己的密码"
  

4.mysql5.7数据库新建库seata

5.在seata库里建表

建表db_store.sql在\seata-server-0.9.0\seata\conf目录里面

-- the table to store GlobalSession data
drop table if exists `global_table`;
create table `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`)
);
 
-- the table to store BranchSession data
drop table if exists `branch_table`;
create table `branch_table` (
  `branch_id` bigint not null,
  `xid` varchar(128) not null,
  `transaction_id` bigint ,
  `resource_group_id` varchar(32),
  `resource_id` varchar(256) ,
  `lock_key` varchar(128) ,
  `branch_type` varchar(8) ,
  `status` tinyint,
  `client_id` varchar(64),
  `application_data` varchar(2000),
  `gmt_create` datetime,
  `gmt_modified` datetime,
  primary key (`branch_id`),
  key `idx_xid` (`xid`)
);
 
-- the table to store lock data
drop table if exists `lock_table`;
create table `lock_table` (
  `row_key` varchar(128) not null,
  `xid` varchar(96),
  `transaction_id` long ,
  `branch_id` long,
  `resource_id` varchar(256) ,
  `table_name` varchar(32) ,
  `pk` varchar(36) ,
  `gmt_create` datetime ,
  `gmt_modified` datetime,
  primary key(`row_key`)
);
 

6.修改seata-server-0.9.0\seata\conf目录下的registry.conf配置文件

registry {
  # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
  type = "nacos"
 
  nacos {
    serverAddr = "localhost:8848"
    namespace = ""
    cluster = "default"
  }
  

目的是：指明注册中心为nacos，及修改nacos连接信息

7.先启动Nacos端口号8848

8.再启动seata-server

1. softs\seata-server-0.9.0\seata\bin
2. seata-server.bat

4. 订单/库存/账户业务数据库准备

以下演示都需要先启动Nacos后启动Seata，保证两个都OK

Nacos没启动报错no available server to connect

4.1 分布式事务业务说明

下订单–>扣库存–>减账户（余额）

4.2 创建业务数据库

seata_order: 存储订单的数据库

seata_storage:存储库存的数据库

seata_account: 存储账户信息的数据库

建库SQL

CREATE DATABASE seata_order；
 
CREATE DATABASE seata_storage；
 
CREATE DATABASE seata_account；

4.3 按照上述3库分别建对应业务表

seata_order库下建t_order表

CREATE TABLE t_order(
    'id' BIGINT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY,
    'user_id' BIGINT(11) DEFAULT NULL COMMENT '用户id',
    'product_id' BIGINT(11) DEFAULT NULL COMMENT '产品id',
    'count' INT(11) DEFAULT NULL COMMENT '数量',
    'money' DECIMAL(11,0) DEFAULT NULL COMMENT '金额',
    'status' INT(1) DEFAULT NULL COMMENT '订单状态：0：创建中; 1：已完结'
) ENGINE=INNODB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;
 
SELECT * FROM t_order;

seata_storage库下建t_storage表

CREATE TABLE t_storage(
    'id' BIGINT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY,
    'product_id' BIGINT(11) DEFAULT NULL COMMENT '产品id',
    'total' INT(11) DEFAULT NULL COMMENT '总库存',
    'used' INT(11) DEFAULT NULL COMMENT '已用库存',
    'residue' INT(11) DEFAULT NULL COMMENT '剩余库存'
) ENGINE=INNODB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;
 
INSERT INTO seata_storage.t_storage('id','product_id','total','used','residue')
VALUES('1','1','100','0','100');
SELECT * FROM t_storage;

seata_account库下建t_account表

CREATE TABLE t_account(
    'id' BIGINT(11) NOT NULL AUTO_INCREMENT PRIMARY KEY COMMENT 'id',
    'user_id' BIGINT(11) DEFAULT NULL COMMENT '用户id',
    'total' DECIMAL(10,0) DEFAULT NULL COMMENT '总额度',
    'used' DECIMAL(10,0) DEFAULT NULL COMMENT '已用余额',
    'residue' DECIMAL(10,0) DEFAULT '0' COMMENT '剩余可用额度'
) ENGINE=INNODB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;
 
INSERT INTO seata_account.t_account('id','user_id','total','used','residue') VALUES('1','1','1000','0','1000')
SELECT * FROM t_account;

4.4 按照上述3库分别建对应的回滚日志表

订单-库存-账户3个库下都需要建各自的回滚日志表

\seata-server-0.9.0\seata\conf目录下的db_undo_log.sql

建表SQL

drop table `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;

最终效果

5. 订单/库存/账户业务微服务准备

业务需求:下订单->减库存->扣余额->改（订单）状态:

5.1 新建订单Order-Module

1.seata-order-service2001

2.POM

 
<dependencies>
    <!--nacos-->
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
    </dependency>
    <!--seata-->
    <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-all</artifactId>
        <version>0.9.0</version>
    </dependency>
    <!--feign-->
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-openfeign</artifactId>
    </dependency>
    <!--web-actuator-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <!--mysql-druid-->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.37</version>
    </dependency>
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid-spring-boot-starter</artifactId>
        <version>1.1.10</version>
    </dependency>
    <dependency>
        <groupId>org.mybatis.spring.boot</groupId>
        <artifactId>mybatis-spring-boot-starter</artifactId>
        <version>2.0.0</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <optional>true</optional>
    </dependency>
</dependencies>

3.YML

server:
  port: 2001
 
spring:
  application:
    name: seata-order-service
  cloud:
    alibaba:
      seata:
        #自定义事务组名称需要与seata-server中的对应
        tx-service-group: fsp_tx_group
    nacos:
      discovery:
        server-addr: localhost:8848
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/seata_order
    username: root
    password: 123456
 
feign:
  hystrix:
    enabled: false
 
logging:
  level:
    io:
      seata: info
 
mybatis:
  mapperLocations: classpath:mapper/*.xml

4.file.conf

transport {
  # tcp udt unix-domain-socket
  type = "TCP"
  #NIO NATIVE
  server = "NIO"
  #enable heartbeat
  heartbeat = true
  #thread factory for netty
  thread-factory {
    boss-thread-prefix = "NettyBoss"
    worker-thread-prefix = "NettyServerNIOWorker"
    server-executor-thread-prefix = "NettyServerBizHandler"
    share-boss-worker = false
    client-selector-thread-prefix = "NettyClientSelector"
    client-selector-thread-size = 1
    client-worker-thread-prefix = "NettyClientWorkerThread"
    # netty boss thread size,will not be used for UDT
    boss-thread-size = 1
    #auto default pin or 8
    worker-thread-size = 8
  }
  shutdown {
    # when destroy server, wait seconds
    wait = 3
  }
  serialization = "seata"
  compressor = "none"
}
 
service {
 #############这里一定要改自己之前service模块！！！！！！！
  vgroup_mapping.fsp_tx_group = "default" 
 
  default.grouplist = "127.0.0.1:8091"
  enableDegrade = false
  disable = false
  max.commit.retry.timeout = "-1"
  max.rollback.retry.timeout = "-1"
  disableGlobalTransaction = false
}
 
 
client {
  async.commit.buffer.limit = 10000
  lock {
    retry.internal = 10
    retry.times = 30
  }
  report.retry.count = 5
  tm.commit.retry.count = 1
  tm.rollback.retry.count = 1
}
 
## transaction log store
store {
  ## store mode: file、db
  mode = "db"
 
  ## file store
  file {
    dir = "sessionStore"
 
    # branch session size , if exceeded first try compress lockkey, still exceeded throws exceptions
    max-branch-session-size = 16384
    # globe session size , if exceeded throws exceptions
    max-global-session-size = 512
    # file buffer size , if exceeded allocate new buffer
    file-write-buffer-cache-size = 16384
    # when recover batch read size
    session.reload.read_size = 100
    # async, sync
    flush-disk-mode = async
  }
 
  ## database store
  db {
    ## the implement of javax.sql.DataSource, such as DruidDataSource(druid)/BasicDataSource(dbcp) etc.
    datasource = "dbcp"
    ## mysql/oracle/h2/oceanbase etc.
    db-type = "mysql"
    driver-class-name = "com.mysql.jdbc.Driver"
    url = "jdbc:mysql://127.0.0.1:3306/seata"
    user = "root"
    password = "123456"
    min-conn = 1
    max-conn = 3
    global.table = "global_table"
    branch.table = "branch_table"
    lock-table = "lock_table"
    query-limit = 100
  }
}
lock {
  ## the lock store mode: local、remote
  mode = "remote"
 
  local {
    ## store locks in user's database
  }
 
  remote {
    ## store locks in the seata's server
  }
}
recovery {
  #schedule committing retry period in milliseconds
  committing-retry-period = 1000
  #schedule asyn committing retry period in milliseconds
  asyn-committing-retry-period = 1000
  #schedule rollbacking retry period in milliseconds
  rollbacking-retry-period = 1000
  #schedule timeout retry period in milliseconds
  timeout-retry-period = 1000
}
 
transaction {
  undo.data.validation = true
  undo.log.serialization = "jackson"
  undo.log.save.days = 7
  #schedule delete expired undo_log in milliseconds
  undo.log.delete.period = 86400000
  undo.log.table = "undo_log"
}
 
## metrics settings
metrics {
  enabled = false
  registry-type = "compact"
  # multi exporters use comma divided
  exporter-list = "prometheus"
  exporter-prometheus-port = 9898
}
 
support {
  ## spring
  spring {
    # auto proxy the DataSource bean
    datasource.autoproxy = false
  }
}
 
 

5.registry.conf

registry {
  # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
  type = "nacos"
 
  nacos {
    serverAddr = "localhost:8848"
    namespace = ""
    cluster = "default"
  }
  eureka {
    serviceUrl = "http://localhost:8761/eureka"
    application = "default"
    weight = "1"
  }
  redis {
    serverAddr = "localhost:6379"
    db = "0"
  }
  zk {
    cluster = "default"
    serverAddr = "127.0.0.1:2181"
    session.timeout = 6000
    connect.timeout = 2000
  }
  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
  type = "file"
 
  nacos {
    serverAddr = "localhost"
    namespace = ""
  }
  consul {
    serverAddr = "127.0.0.1:8500"
  }
  apollo {
    app.id = "seata-server"
    apollo.meta = "http://192.168.1.204:8801"
  }
  zk {
    serverAddr = "127.0.0.1:2181"
    session.timeout = 6000
    connect.timeout = 2000
  }
  etcd3 {
    serverAddr = "http://localhost:2379"
  }
  file {
    name = "file.conf"
  }
}

6.domain

CommonResult

package com.atguigu.springcloud.alibaba.domain;
 
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
 
 
@Data
@AllArgsConstructor
@NoArgsConstructor
public class CommonResult<T>
{
    private Integer code;
    private String  message;
    private T       data;
 
    public CommonResult(Integer code, String message)
    {
        this(code,message,null);
    }
}
 

Order

package com.atguigu.springcloud.alibaba.domain;
 
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
 
import java.math.BigDecimal;
 
 
@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
}
 

7.Dao接口及实现

OrderDao

package com.atguigu.springcloud.alibaba.dao;
 
import com.atguigu.springcloud.alibaba.domain.Order;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
 
@Mapper
public interface OrderDao
{
    //新建订单
    void create(Order order);
 
    //修改订单状态，从零改为1
    void update(@Param("userId") Long userId,@Param("status") Integer status);
}
 

resources文件夹下新建mapper文件夹后添加OrderMapper.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.atguigu.springcloud.alibaba.dao.OrderDao">
 
    <resultMap id="BaseResultMap" type="com.atguigu.springcloud.alibaba.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_order set status = 1
        where user_id=#{userId} and status = #{status};
    </update>
 
</mapper>
 

8.Service接口及实现

OrderService

package com.atguigu.springcloud.alibaba.service;
 
import com.atguigu.springcloud.alibaba.domain.Order;
 
 
public interface OrderService{
    void create(Order order);
}
 

OrderServiceImpl

package com.atguigu.springcloud.alibaba.service.impl;
 
import com.atguigu.springcloud.alibaba.dao.OrderDao;
import com.atguigu.springcloud.alibaba.domain.Order;
import com.atguigu.springcloud.alibaba.service.AccountService;
import com.atguigu.springcloud.alibaba.service.OrderService;
import com.atguigu.springcloud.alibaba.service.StorageService;
import io.seata.spring.annotation.GlobalTransactional;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Service;
 
import javax.annotation.Resource;
 
 
@Service
@Slf4j
public class OrderServiceImpl implements OrderService
{
    @Resource
    private OrderDao orderDao;
    @Resource
    private StorageService storageService;
    @Resource
    private 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
     */
     
    @Override
    @GlobalTransactional(name = "fsp-create-order",rollbackFor = Exception.class)
    public void create(Order order){
        log.info("----->开始新建订单");
        //新建订单
        orderDao.create(order);
 
        //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");
 
        //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");
 
         
        //修改订单状态，从零到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");
 
    }
}
 

StorageService

package com.atguigu.springcloud.alibaba.service;
 
import com.atguigu.springcloud.alibaba.domain.CommonResult;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
 
import java.math.BigDecimal;
 
 
@FeignClient(value = "seata-storage-service")
public interface StorageService{
    @PostMapping(value = "/storage/decrease")
    CommonResult decrease(@RequestParam("productId") Long productId, @RequestParam("count") Integer count);
}
 

AccountService

package com.atguigu.springcloud.alibaba.service;
 
import com.atguigu.springcloud.alibaba.domain.CommonResult;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
 
import java.math.BigDecimal;
 
@FeignClient(value = "seata-account-service")
public interface AccountService{
    @PostMapping(value = "/account/decrease")
    CommonResult decrease(@RequestParam("userId") Long userId, @RequestParam("money") BigDecimal money);
}
 

9.Controller

package com.atguigu.springcloud.alibaba.controller;
 
import com.atguigu.springcloud.alibaba.domain.CommonResult;
import com.atguigu.springcloud.alibaba.domain.Order;
import com.atguigu.springcloud.alibaba.service.OrderService;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
 
import javax.annotation.Resource;
 
 
@RestController
public class OrderController{
    @Resource
    private OrderService orderService;
 
 
    @GetMapping("/order/create")
    public CommonResult create(Order order)
    {
        orderService.create(order);
        return new CommonResult(200,"订单创建成功");
    }
}
 

10.Config配置

MyBatisConfig

package com.atguigu.springcloud.alibaba.config;
 
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Configuration;
 
 
@Configuration
@MapperScan({"com.atguigu.springcloud.alibaba.dao"})
public class MyBatisConfig {
 
}
 

DataSourceProxyConfig

package com.atguigu.springcloud.alibaba.config;
 
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;
 
 
@Configuration
public class DataSourceProxyConfig {
 
 
    @Value("${mybatis.mapperLocations}")
    private String mapperLocations;
 
    
    @Bean
    @ConfigurationProperties(prefix = "spring.datasource")
    public DataSource druidDataSource(){
        return new DruidDataSource();
    }
 
    
    @Bean
    public DataSourceProxy dataSourceProxy(DataSource dataSource) {
        return new DataSourceProxy(dataSource);
    }
 
    
    @Bean
    public SqlSessionFactory sqlSessionFactoryBean(DataSourceProxy dataSourceProxy) throws Exception {
        SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        sqlSessionFactoryBean.setDataSource(dataSourceProxy);
        sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources(mapperLocations));
        sqlSessionFactoryBean.setTransactionFactory(new SpringManagedTransactionFactory());
        return sqlSessionFactoryBean.getObject();
    }
 
}
 

11.主启动

package com.atguigu.springcloud.alibaba;
 
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;
 
@EnableDiscoveryClient
@EnableFeignClients
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)//取消数据源自动创建的配置
public class SeataOrderMainApp2001{
 
    public static void main(String[] args)
    {
        SpringApplication.run(SeataOrderMainApp2001.class, args);
    }
}
 

5.2 新建库存Storage-Module

1.seata-order-service2002

2.POM

3.YML

server:
  port: 2002
 
spring:
  application:
    name: seata-storage-service

4.file.conf

5.registry.conf

6.domain

CommonResult同上

package com.atguigu.springcloud.alibaba.domain;
 
import lombok.Data;
 
@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;
}
 

7.Dao接口及实现

StorageDao

package com.atguigu.springcloud.alibaba.dao;
 
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
 
@Mapper
public interface StorageDao {
 
 
    //扣减库存信息
    void decrease(@Param("productId") Long productId, @Param("count") Integer count);
}
 

StorageMapper.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.atguigu.springcloud.alibaba.dao.StorageDao">
 
    <resultMap id="BaseResultMap" type="com.atguigu.springcloud.alibaba.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">
        UPDATE
            t_storage
        SET
            used = used + #{count},residue = residue - #{count}
        WHERE
            product_id = #{productId}
    </update>
 
</mapper>
 

8.Service接口及实现

StorageService

package com.atguigu.springcloud.alibaba.service;
 
 
public interface StorageService {
    
     // 扣减库存
    void decrease(Long productId, Integer count);
}
 

StorageServiceImpl

package com.atguigu.springcloud.alibaba.service.impl;
 
import com.atguigu.springcloud.alibaba.dao.StorageDao;
import com.atguigu.springcloud.alibaba.service.StorageService ;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
 
import javax.annotation.Resource;
 
 
@Service
public class StorageServiceImpl implements StorageService {
 
    private static final Logger LOGGER = LoggerFactory.getLogger(StorageServiceImpl.class);
 
    @Resource
    private StorageDao storageDao;
 
     // 扣减库存
    @Override
    public void decrease(Long productId, Integer count) {
        LOGGER.info("------->storage-service中扣减库存开始");
        storageDao.decrease(productId,count);
        LOGGER.info("------->storage-service中扣减库存结束");
    }
}
 

9.Controller

package com.atguigu.springcloud.alibaba.controller;
 
 
import com.atguigu.springcloud.alibaba.domain.CommonResult ;
import com.atguigu.springcloud.alibaba.service.StorageService ;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
 
@RestController
public class StorageController {
 
    @Autowired
    private 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！");
    }
}
 

10.Config配置

11.主启动

5.3 新建账户Account-Module

1.seata-order-service2003

2.POM

3.YML

server:
  port: 2003
 
spring:
  application:
    name: seata-account-service

4.file.conf

5.registry.conf

6.domain

CommonResult同上

package com.atguigu.springcloud.alibaba.domain;
 
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
 
import java.math.BigDecimal;
 
@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;
}

7.Dao接口及实现

AccountDao

package com.atguigu.springcloud.alibaba.dao;
 
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.springframework.stereotype.Component;
import org.springframework.stereotype.Repository;
 
import java.math.BigDecimal;
 
@Mapper
public interface AccountDao {
 
    /**
     * 扣减账户余额
     */
    void decrease(@Param("userId") Long userId, @Param("money") BigDecimal money);
}
 

<?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.atguigu.springcloud.alibaba.dao.AccountDao">
 
    <resultMap id="BaseResultMap" type="com.atguigu.springcloud.alibaba.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_account
        SET
          residue = residue - #{money},used = used + #{money}
        WHERE
          user_id = #{userId};
    </update>
 
</mapper>
 

8.Service接口及实现

package com.atguigu.springcloud.alibaba.service;
 
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
 
import java.math.BigDecimal;
 
 
public interface AccountService {
 
    /**
     * 扣减账户余额
     */
    void decrease(@RequestParam("userId") Long userId, @RequestParam("money") BigDecimal money);
}

package com.atguigu.springcloud.alibaba.service.impl;
 
 
import com.atguigu.springcloud.alibaba.dao.AccountDao;
import com.atguigu.springcloud.alibaba.service.AccountService ;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
 
import javax.annotation.Resource;
import java.math.BigDecimal;
import java.util.concurrent.TimeUnit;
 
/**
 * 账户业务实现类
 */
@Service
public class AccountServiceImpl implements AccountService {
 
    private static final Logger LOGGER = LoggerFactory.getLogger(AccountServiceImpl.class);
 
 
    @Resource
    AccountDao accountDao;
 
    /**
     * 扣减账户余额
     */
    @Override
    public void decrease(Long userId, BigDecimal money) {
        
         LOGGER.info("------->account-service中扣减账户余额开始");
        try { TimeUnit.SECONDS.sleep(20); } catch (InterruptedException e) { e.printStackTrace(); }
        accountDao.decrease(userId,money);
        LOGGER.info("------->account-service中扣减账户余额结束");
    }
}

9.Controller

package com.atguigu.springcloud.alibaba.controller;
 
import com.atguigu.springcloud.alibaba.domain.CommonResult ;
import com.atguigu.springcloud.alibaba.service.AccountService ;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
 
import javax.annotation.Resource;
import java.math.BigDecimal;
 
@RestController
public class AccountController {
 
    @Resource
    AccountService 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！");
    }
}

10.Config配置

11.主启动

5. Test

下订单->减库存->扣余额->改（订单）状态

数据库初始情况

5.1 正常下单

http://localhost:2001/order/create?userid=1&productId=1&count=10&money=100

数据库情况

5.2 超时异常，没加@GlobalTransactional

AccountServiceImpl添加超时

当库存和账户余额扣减后，订单状态并没有设置为已经完成，没有从零改为1

而且由于feign的重试机制，账户余额还有可能被多次扣减

5.3 超时异常，添加@GlobalTransactional

AccountServiceImpl添加超时

OrderServiceImpl添加@GlobalTransactional

下单后数据库数据并没有任何改变,记录都添加不进来

6. Seata之原理简介

2019年1月份蚂蚁金服和阿里巴巴共同开源的分布式事务解决方案

Simple Extensible Autonomous Transaction Architecture,简单可扩展自治事务框架

再看TC/TM/RM三大组件

分布式事务的执行流程

1. TM开启分布式事务(TM向TC注册全局事务记录)
2. 换业务场景，编排数据库，服务等事务内资源（RM向TC汇报资源准备状态）
3. TM结束分布式事务，事务一阶段结束（TM通知TC提交/回滚分布式事务）
4. TC汇总事务信息，决定分布式事务是提交还是回滚
5. TC通知所有RM提交/回滚资源，事务二阶段结束。

AT模式如何做到对业务的无侵入

是什么

一阶段加载

二阶段提交

二阶段回滚

补充