- 1、Alibaba Seata处理分布式事务
- tcp udt unix-domain-socket
- NIO NATIVE
- enable heartbeat
- thread factory for netty
- netty boss thread size,will not be used for UDT
- auto default pin or 8
- when destroy server, wait seconds
- vgroup->rgroup
- only support single node
- degrade current not support
- disable
- unit ms,s,m,h,d represents milliseconds, seconds, minutes, hours, days, default permanent
- schedule committing retry period in milliseconds
- schedule asyn committing retry period in milliseconds
- schedule rollbacking retry period in milliseconds
- schedule timeout retry period in milliseconds
- schedule delete expired undo_log in milliseconds
- multi exporters use comma divided
- 6、Seata之原理简介
1、Alibaba Seata处理分布式事务
1、分布式事务问题
1、分布式前
- 单机单库没这个问题
-
2、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
1、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
- http://seata.io/zh-cn/
2、一个典型的分布式事务过程
- http://seata.io/zh-cn/
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;
- 说白了就是seata-server
- 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;
- 说白白了就是全局@GlobalTransactional
- 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；
- Transaction Coordinator(TC)
- Transaction ID XID
- 处理过程
3、下载
https://github.com/seata/seata/releases
4、使用
- 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
https://github.com/seata/seata/releases/download/v1.4.2/seata-server-1.4.2.zip3、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
mysql5.7数据库新建库seata
在seata库里建表
目的是：指明注册中心为nacos，及修改nacos连接信息
registry { # file 、nacos 、eureka、redis、zk、consul、etcd3、sofa type = "nacos" nacos { serverAddr = "localhost:8848" namespace = "" cluster = "default" }6、启动
启动Nacos集群1111
- 参考nacos章节
启动seata-server
这里我们会创建三个服务, 一个订单服务,一个库存服务,一个账户服务。当用户下单时，会在订单服务中创建一个订单, 然后通过远程调用库存服务来扣减下单商品的库存,再通过远程调用账户服务来扣减用户账户里面的余额，τ最后在订单服务中修改订单状态为已完成。该操作跨越二三个数据库,有两次远程调用，很明显会有分布式事务问题。
-
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
CREATE DATABASE seata_order; CREATE DATABASE seata_storage; CREATE DATABASE seata_account; show databases;3、按照上述3库分别建对应业务表
seata_order库下建t_order表
- seata_storage库下建t_storage表
- seata_account库下建t_account表
use seata_order;
CREATE TABLE t_order (
`id` BIGINT(11) NOT NULL AUTO_INCREMENT,
`user_id` BIGINT(11) DEFAULT NULL COMMENT '用id',
`product_id` BIGINT(11) DEFAULT NULL COMMENT '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',
PRIMARY KEY(`id`)
) ENGINE=INNODB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8;
SELECT * FROM t_order;
use seata_storage;
CREATE TABLE t_storage (
`id` BIGINT(11) NOT NULL AUTO_INCREMENT,
`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',
PRIMARY KEY(`id`)
) 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;
use seata_account;
CREATE TABLE t_account (
`id` BIGINT(11) NOT NULL AUTO_INCREMENT 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',
PRIMARY KEY(`id`)
) 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、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
``sql -- the table to store seata xid data -- 0.7.0+ add context -- you must to init this sql for you business databese. the seata server not need it. -- 此脚本必须初始化在你当前的业务数据库中，用于AT 模式XID记录。与server端无关（注：业务数据库） -- 注意此处0.3.0+ 增加唯一索引 ux_undo_log use seata_order; drop tableundo_log; CREATE TABLEundo_log(idbigint(20) NOT NULL AUTO_INCREMENT,branch_idbigint(20) NOT NULL,xidvarchar(100) NOT NULL,contextvarchar(128) NOT NULL,rollback_infolongblob NOT NULL,log_statusint(11) NOT NULL,log_createddatetime NOT NULL,log_modifieddatetime NOT NULL,extvarchar(100) DEFAULT NULL, PRIMARY KEY (id), UNIQUE KEYux_undo_log(xid,branch_id`) ) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
use seata_account;
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;
use seata_storage;
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;
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## 5、订单/库存/账户业务微服务准备
- 下订单->减库存->扣余额->改（订单）状态
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### 1、创建seata-order-service2001
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#### 1、修改pom
```xml
<?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.daijunyi</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<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>
2、修改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: fsp_tx_group
nacos:
discovery:
server-addr: localhost:1111
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:10005/seata_order
username: root
password: 123456
feign:
hystrix:
enabled: false
logging:
level:
io:
seata: info
mybatis:
mapperLocations: classpath:mapper/*.xml
3、在resources文件夹下添加file.conf和registry.conf文件
- file.conf
```json
transport {
tcp udt unix-domain-socket
type = “TCP”NIO NATIVE
server = “NIO”enable heartbeat
heartbeat = truethread 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 = 1auto default pin or 8
worker-thread-size = 8 } shutdown {when destroy server, wait seconds
wait = 3 } serialization = “seata” compressor = “none” } service {vgroup->rgroup
vgroup_mapping.fsp_tx_group = “default”only support single node
default.grouplist = “127.0.0.1:8091”degrade current not support
enableDegrade = falsedisable
disable = falseunit 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://127.0.0.1:10005/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
} }
- registry.conf
```yaml
registry {
# file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
type = "nacos"
nacos {
serverAddr = "localhost:1111"
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"
}
}
4、添加config 配置文件
- DataSourceProxyConfig ```java package com.daijunyi.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();
}
}
- MyBatisConfig
```java
package com.daijunyi.config;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
@Configuration
@MapperScan({"com.daijunyi.dao"})
public class MyBatisConfig {
}
5、主启动类
package com.daijunyi;
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 SeataOrderService2001 {
public static void main(String[] args) {
SpringApplication.run(SeataOrderService2001.class,args);
}
}
6、添加domain
- CommonResult ```java package com.daijunyi.domain;
import lombok.AllArgsConstructor; import lombok.Data; import lombok.NoArgsConstructor;
@Data
@AllArgsConstructor
@NoArgsConstructor
public class CommonResult
public CommonResult(Integer code, String message)
{
this(code,message,null);
}
}
- Order
```java
package com.daijunyi.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、添加dao层
- OrderDao ```java package com.daijunyi.dao;
import com.daijunyi.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);
}
- 在resource文件夹下创建mapper文件夹，并创建OrderMapper.xml
```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.daijunyi.dao.OrderDao">
<resultMap id="BaseResultMap" type="com.daijunyi.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层
- AccountService ```java package com.daijunyi.service;
import com.daijunyi.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); }
- StorageService
```java
package com.daijunyi.service;
import com.daijunyi.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);
}
- OrderService ```java package com.daijunyi.service;
import com.daijunyi.domain.Order;
public interface OrderService{ void create(Order order); }
- OrderServiceImpl
```java
package com.daijunyi.service.impl;
import com.daijunyi.dao.OrderDao;
import com.daijunyi.domain.Order;
import com.daijunyi.service.AccountService;
import com.daijunyi.service.OrderService;
import com.daijunyi.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
*/
@GlobalTransactional(name = "fsp-create-order",rollbackFor = Exception.class)
@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");
}
}
9、创建controller层
- OrderController ```java package com.daijunyi.controller;
import com.daijunyi.domain.CommonResult; import com.daijunyi.domain.Order; import com.daijunyi.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");
}
}
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### 2、seata-order-service2002
<a name="sRUjE"></a>
#### 1、修改pom
```xml
<?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.daijunyi</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<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>
2、修改yaml
server:
port: 2002
spring:
application:
name: seata-storage-service
cloud:
alibaba:
seata:
tx-service-group: fsp_tx_group
nacos:
discovery:
server-addr: localhost:1111
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:10005/seata_storage
username: root
password: 123456
logging:
level:
io:
seata: info
mybatis:
mapperLocations: classpath:mapper/*.xml
3、在resource文件夹上文件
- 添加和seata-order-service2001一样的file.conf和registry.conf
4、复制seata-order-service2001中的两个config文件到项目中
5、主启动类
```java package com.daijunyi;
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;
@SpringBootApplication(exclude = {DataSourceAutoConfiguration.class}) @EnableDiscoveryClient public class SeataOrderService2002 { public static void main(String[] args) { SpringApplication.run(SeataOrderService2002.class,args); } }
<a name="FnUX5"></a>
#### 6、添加domain
- 复制2001中的CommonResult
- Storage
```java
package com.daijunyi.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、添加dao层
- StorageDao ```java package com.daijunyi.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);
}
- 在resource下创建mapper，并添加文件StorageMapper.xml
```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.daijunyi.dao.StorageDao">
<resultMap id="BaseResultMap" type="com.daijunyi.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层
- StorageService ```java package com.daijunyi.service;
public interface StorageService { // 扣减库存 void decrease(Long productId, Integer count); }
- StorageServiceImpl
```java
package com.daijunyi.service.impl;
import com.daijunyi.dao.StorageDao;
import com.daijunyi.service.StorageService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
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
- StorageController ```java package com.daijunyi.controller;
import com.daijunyi.domain.CommonResult; import com.daijunyi.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！");
}
}
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### 3、seata-order-service2003
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#### 1、修改pom.xml
```xml
<?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.daijunyi</groupId>
<version>1.0-SNAPSHOT</version>
</parent>
<modelVersion>4.0.0</modelVersion>
<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>
2、修改yaml
server:
port: 2003
spring:
application:
name: seata-account-service
cloud:
alibaba:
seata:
tx-service-group: fsp_tx_group
nacos:
discovery:
server-addr: localhost:1111
datasource:
driver-class-name: com.mysql.jdbc.Driver
url: jdbc:mysql://localhost:10005/seata_account
username: root
password: 123456
feign:
hystrix:
enabled: false
logging:
level:
io:
seata: info
mybatis:
mapperLocations: classpath:mapper/*.xml
3、在resource文件夹下
复制2001项目中的file.conf和registry.conf文件到目录下
4、复制2001项目中config配置到目录下
DataSourceProxyConfig
- MyBatisConfig
5、主启动类
```java package com.daijunyi;
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 SeataOrderService2003 { public static void main(String[] args) { SpringApplication.run(SeataOrderService2003.class,args); } }
<a name="YsJ6V"></a>
#### 6、添加domain
- 复制2001项目中的CommonResult
- Account
```java
package com.daijunyi.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、添加dao
- AccountDao ```java package com.daijunyi.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);
}
- 在resource下创建mapper文件夹，并且创建AccountMapper.xml
```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.daijunyi.dao.AccountDao">
<resultMap id="BaseResultMap" type="com.daijunyi.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层
- AccountService ```java package com.daijunyi.service;
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
```java
package com.daijunyi.service.impl;
import com.daijunyi.dao.AccountDao;
import com.daijunyi.service.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");
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层
package com.daijunyi.controller;
import com.daijunyi.domain.CommonResult;
import com.daijunyi.service.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！");
}
}
4、测试
1、下订单->减库存->扣余额->改（订单）状态
2、数据库初始情况
3、正常下单
http://localhost:2001/order/create?userId=1&productId=1&count=10&money=100
- 数据库情况
-
4、超时异常，没加@GlobalTransactional
AccountServiceImpl添加超时
- 数据库情况
故障情况
AccountServiceImpl添加超时
- OrderServiceImpl@GlobalTransactional
下单后数据库数据并没有任何改变
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
2、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。
3、AT模式如何做到对业务的无侵入
1、是什么
http://seata.io/zh-cn/docs/overview/what-is-seata.html
前提
- 基于支持本地 ACID 事务的关系型数据库。
- Java 应用，通过 JDBC 访问数据库。
- 整体机制
- 解析 SQL：得到 SQL 的类型（UPDATE），表（product），条件（where name = ‘TXC’）等相关的信息。
- 查询前镜像：根据解析得到的条件信息，生成查询语句，定位数据。
select id, name, since from product where name = ‘TXC’;
得到前镜像：
| id | name | since |
|---|---|---|
| 1 | TXC | 2014 |
- 执行业务 SQL：更新这条记录的 name 为 ‘GTS’。
- 查询后镜像：根据前镜像的结果，通过 主键 定位数据。
select id, name, since from product where id = 1;
得到后镜像：
| id | name | since |
|---|---|---|
| 1 | GTS | 2014 |
插入回滚日志：把前后镜像数据以及业务 SQL 相关的信息组成一条回滚日志记录，插入到 UNDO_LOG 表中。
{ "branchId": 641789253, "undoItems": [{ "afterImage": { "rows": [{ "fields": [{ "name": "id", "type": 4, "value": 1 }, { "name": "name", "type": 12, "value": "GTS" }, { "name": "since", "type": 12, "value": "2014" }] }], "tableName": "product" }, "beforeImage": { "rows": [{ "fields": [{ "name": "id", "type": 4, "value": 1 }, { "name": "name", "type": 12, "value": "TXC" }, { "name": "since", "type": 12, "value": "2014" }] }], "tableName": "product" }, "sqlType": "UPDATE" }], "xid": "xid:xxx" }提交前，向 TC 注册分支：申请 product 表中，主键值等于 1 的记录的 全局锁 。
- 本地事务提交：业务数据的更新和前面步骤中生成的 UNDO LOG 一并提交。
-
3、二阶段提交
收到 TC 的分支提交请求，把请求放入一个异步任务的队列中，马上返回提交成功的结果给 TC。
- 异步任务阶段的分支提交请求将异步和批量地删除相应 UNDO LOG 记录。
4、二阶段回滚
- 收到 TC 的分支回滚请求，开启一个本地事务，执行如下操作。
- 通过 XID 和 Branch ID 查找到相应的 UNDO LOG 记录。
- 数据校验：拿 UNDO LOG 中的后镜与当前数据进行比较，如果有不同，说明数据被当前全局事务之外的动作做了修改。这种情况，需要根据配置策略来做处理，详细的说明在另外的文档中介绍。
- 根据 UNDO LOG 中的前镜像和业务 SQL 的相关信息生成并执行回滚的语句：
update product set name = 'TXC' where id = 1;- 提交本地事务。并把本地事务的执行结果（即分支事务回滚的结果）上报给 TC。
4、补充
gulishang
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