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
总结
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
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
一个典型的分布式事务过程:
1(ID)+3(组件)
分布式事务处理过程的-ID+三组件模型
Transaction ID XID
全局唯一的事务ID
3组件概念:
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;
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;
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
发布说明:https://github.com/seata/seata/releases
怎么玩
之前使用Spring 的@Transactional注解来控制事务
现在使用SEATA需要使用@GlobalTransactional注解
SEATA的分布式交易解决方案
Seata-Server安装
官网地址:http://seata.io/zh-cn/
下载版本,本示例以v0.9.0为例
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
file.conf文件中修改:
service模块
事务组的名称可以随意取
store模块
将数据库连接信息改为自己的
mysql数据库新建库seata
在seata库里建表
建表语句db_store.sql在\seata-server-0.9.0\seata\conf目录里面
修改seata-server-0.9.0\seata\conf目录下的registry.conf配置文件
先启动Nacos端口号8848
再启动seata-server
执行softs\seata-server-0.9.0\seata\bin下的seata-server.bat
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。Seata没启动报错no available server to connect
分布式事务业务说明
下订单–>扣库存–>减账户(余额)
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
CREATE DATABASE seata_order;
CREATE DATABASE seata_storage;
CREATE DATABASE seata_account;
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;
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
建表语句在\seata-server-0.9.0\seata\conf目录下的db_undo_log.sql
在以上三个库中各自执行一遍
最终效果
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
新建订单Order-Module
建module
新建seata-order-service2001模块
改POM
<?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">
<parent>
<artifactId>cloud2020</artifactId>
<groupId>com.mg.springcloud</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<groupId>com.mg.springcloud</groupId>
<artifactId>seata-order-service2001</artifactId>
<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>
</project>
写yaml
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: mg_tx_test
nacos:
discovery:
server-addr: localhost:8848
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:3306/seata_order
username: root
password: root
feign:
hystrix:
enabled: false
logging:
level:
io:
seata: info
mybatis:
mapperLocations: classpath:mapper/*.xml
file.conf
在resource文件中新建file.conf文件,文件内容就是\seata-server-0.9.0\seata\conf\file.conf的文件内容
注意service模块的配置vgroup_mapping.mg_tx_test = "default"
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 {
vgroup_mapping.mg_tx_test = "default"
#only support single node
default.grouplist = "127.0.0.1:8091"
#degrade current not support
enableDegrade = false
#disable
disable = false
#unit ms,s,m,h,d represents milliseconds, seconds, minutes, hours, days, default permanent
max.commit.retry.timeout = "-1"
max.rollback.retry.timeout = "-1"
}
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 = "root"
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
}
}
registry.conf
在resource文件中新建registry.conf文件,文件内容就是\seata-server-0.9.0\seata\conf\registry.conf的文件内容
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"
}
}
domain
CommonResult
package com.mg.springcloud.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.mg.springcloud.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
}
Dao接口及实现
OrderDao
package com.mg.springcloud.dao;
import com.mg.springcloud.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);
}
OrderMapper.xml
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.mg.springcloud.dao.OrderDao">
<resultMap id="BaseResultMap" type="com.mg.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_order set status = 1
where user_id=#{userId} and status = #{status};
</update>
</mapper>
Service接口及实现
OrderService
package com.mg.springcloud.service;
import com.mg.springcloud.domain.Order;
public interface OrderService{
void create(Order order);
}
OrderServiceImpl
package com.mg.springcloud.service.impl;
import com.mg.springcloud.dao.OrderDao;
import com.mg.springcloud.domain.Order;
import com.mg.springcloud.service.AccountService;
import com.mg.springcloud.service.OrderService;
import com.mg.springcloud.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
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.mg.springcloud.service;
import com.mg.springcloud.domain.CommonResult;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
@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.mg.springcloud.service;
import com.mg.springcloud.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);
}
Controller
package com.mg.springcloud.controller;
import com.mg.springcloud.domain.CommonResult;
import com.mg.springcloud.domain.Order;
import com.mg.springcloud.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");
}
}
Config配置
MyBatisConfig
package com.mg.springcloud.config;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Configuration;
@Configuration
@MapperScan({"com.mg.springcloud.dao"})
public class MyBatisConfig {
}
DataSourceProxyConfig
package com.mg.springcloud.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();
}
}
主启动
package com.mg.springcloud;
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);
}
}
新建库存Storage-Module
建module
新建seata-order-service2002模块
改POM
引入的依赖同上
<?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">
<parent>
<artifactId>cloud2020</artifactId>
<groupId>com.mg.springcloud</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<groupId>com.mg.springcloud</groupId>
<artifactId>seata-order-service2002</artifactId>
<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>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.0.0</version>
</dependency>
<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.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
</dependencies>
</project>
写yaml
同上,注意端口和应用名称的变化
server:
port: 2002
spring:
application:
name: seata-storage-service
cloud:
alibaba:
seata:
tx-service-group: mg_tx_test
nacos:
discovery:
server-addr: localhost:8848
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:3306/seata_storage
username: root
password: root
logging:
level:
io:
seata: info
mybatis:
mapperLocations: classpath:mapper/*.xml
file.conf
同上
registry.conf
同上
domain
CommonResult
同上
Storage
package com.mg.springcloud.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;
}
Dao接口及实现
StorageDao
package com.mg.springcloud.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
resources文件夹下新建mapper文件夹后添加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.mg.springcloud.dao.StorageDao">
<resultMap id="BaseResultMap" type="com.mg.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">
UPDATE
t_storage
SET
used = used + #{count},residue = residue - #{count}
WHERE
product_id = #{productId}
</update>
</mapper>
Service接口及实现
StorageService
package com.mg.springcloud.services;
public interface StorageService {
// 扣减库存
void decrease(Long productId, Integer count);
}
StorageServiceImpl
package com.mg.springcloud.services.impl;
import com.mg.springcloud.dao.StorageDao;
import com.mg.springcloud.services.StorageService ;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
public class StorageServiceImpl implements StorageService {
private static final Logger LOGGER = LoggerFactory.getLogger(StorageServiceImpl.class);
@Autowired
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");
}
}
Controller
package com.mg.springcloud.controller;
import com.mg.springcloud.domain.CommonResult ;
import com.mg.springcloud.services.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!");
}
}
Config配置
MyBatisConfig
同上
DataSourceProxyConfig
同上
主启动
package com.mg.springcloud;
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;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.concurrent.ForkJoinWorkerThread;
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
@EnableDiscoveryClient
@EnableFeignClients
public class SeataStorageServiceApplication2002
{
public static void main(String[] args)
{
SpringApplication.run(SeataStorageServiceApplication2002.class, args);
}
}
新建账户Account-Module
建module
新建seata-order-service2003模块
改POM
引入的依赖同上
<<?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">
<parent>
<artifactId>cloud2020</artifactId>
<groupId>com.mg.springcloud</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<groupId>com.mg.springcloud</groupId>
<artifactId>seata-order-service2003</artifactId>
<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>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.0.0</version>
</dependency>
<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.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
</dependencies>
</project>
写yaml
同上,注意端口和应用名称的变化
server:
port: 2003
spring:
application:
name: seata-account-service
cloud:
alibaba:
seata:
tx-service-group: mg_tx_test
nacos:
discovery:
server-addr: localhost:8848
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:3306/seata_account
username: root
password: root
feign:
hystrix:
enabled: false
logging:
level:
io:
seata: info
mybatis:
mapperLocations: classpath:mapper/*.xml
file.conf
同上
registry.conf
同上
domain
CommonResult
同上
Account
package com.mg.springcloud.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;
}
Dao接口及实现
StorageDao
package com.mg.springcloud.dao;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import java.math.BigDecimal;
@Mapper
public interface AccountDao {
/**
* 扣减账户余额
*/
void decrease(@Param("userId") Long userId, @Param("money") BigDecimal money);
}
AccountMapper.xml
resources文件夹下新建mapper文件夹后添加AccountMapper.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.mg.springcloud.dao.AccountDao">
<resultMap id="BaseResultMap" type="com.mg.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_account
SET
residue = residue - #{money},used = used + #{money}
WHERE
user_id = #{userId};
</update>
</mapper>
Service接口及实现
AccountService
package com.mg.springcloud.services;
import org.springframework.web.bind.annotation.RequestParam;
import java.math.BigDecimal;
public interface AccountService {
/**
* 扣减账户余额
*/
void decrease(@RequestParam("userId") Long userId, @RequestParam("money") BigDecimal money);
}
AccountServiceImpl
package com.mg.springcloud.services.impl;
import com.mg.springcloud.dao.AccountDao;
import com.mg.springcloud.services.AccountService ;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
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");
accountDao.decrease(userId,money);
LOGGER.info("------->account-service中扣减账户余额结束");
}
}
Controller
package com.mg.springcloud.controller;
import com.mg.springcloud.domain.CommonResult ;
import com.mg.springcloud.services.AccountService ;
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!");
}
}
Config配置
MyBatisConfig
同上
DataSourceProxyConfig
同上
主启动
package com.mg.springcloud;
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;
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
@EnableDiscoveryClient
@EnableFeignClients
public class SeataAccountMainApp2003 {
public static void main(String[] args)
{
SpringApplication.run(SeataAccountMainApp2003.class, args);
}
}
测试
先启动nacos,再启动Seata
下订单->减库存->扣余额->改(订单)状态
数据库初始情况
正常下单
http://localhost:2001/order/create?userid=1&producrid=1&counr=10&money=100
数据库情况:
超时异常,没加@GlobalTransactional
AccountServiceImpl添加超时
package com.mg.springcloud.services.impl;
import com.mg.springcloud.dao.AccountDao;
import com.mg.springcloud.services.AccountService ;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
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");
//添加超时
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");
}
}
访问:http://localhost:2001/order/create?userid=1&producrid=1&counr=10&money=100
数据库情况:
故障情况
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
超时异常,添加@GlobalTransactional
AccountServiceImpl添加超时,同上
OrderServiceImpl添加@GlobalTransactional注解
package com.mg.springcloud.service.impl;
import com.mg.springcloud.dao.OrderDao;
import com.mg.springcloud.domain.Order;
import com.mg.springcloud.service.AccountService;
import com.mg.springcloud.service.OrderService;
import com.mg.springcloud.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 = "mg-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");
}
}
访问:http://localhost:2001/order/create?userid=1&producrid=1&counr=10&money=100下单后数据库数据并没有任何改变,记录都添加不进来
Seata之原理简介
Seata
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:
TM开启分布式事务(TM向TC注册全局事务记录)
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)
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)
TC汇总事务信息,决定分布式事务是提交还是回滚
TC通知所有RM提交/回滚资源,事务二阶段结束。