SpringCloud Alibaba Seata處理分布式事務
分布式事務問題
分布式前
單機庫存沒這個問題
O(∩_∩)O
從1:1->1:N->N:N
分布式之后
單體應用被拆分成微服務應用,原來的三個模塊被拆分成三個獨立的應用,分別使用三個獨立的數據源,
業務操作需要調用三個服務來完成。此時每個服務內部的數據一致性由本地事務來保證, 但是全局的數據一致性問題沒法保證。
一句話
一次業務操作需要垮多個數據源或需要垮多個系統進行遠程調用,就會產生分布式事務問題
Seata簡介
是什么
Seata是一款開源的分布式事務解決方案,致力於在微服務架構下提供高性能和簡單易用的分布式事務服務
官網地址
http://seata.io/zh-cn/
能干嘛
一個典型的分布式事務過程
分布式事務處理過程-ID+三組件模型
Transaction ID(XID)
全局唯一的事務id
三組件概念
- Transaction Coordinator(TC):事務協調器,維護全局事務的運行狀態,負責協調並驅動全局事務的提交或回滾
- Transaction Manager(TM):控制全局事務的邊界,負責開啟一個全局事務,並最終發起全局提交或全局回滾的決議
- Resource Manager(RM):控制分支事務,負責分支注冊、狀態匯報,並接受事務協調的指令,驅動分支(本地)事務的提交和回滾
處理過程
在哪下
發布說明: https://github.com/seata/seata/releases
怎么玩
本地@Transational
全局@GlobalTranstional
seata的分布式交易解決方案
Seata-Server安裝
1.官網地址
https://seata.io/zh-cn/
2.下載版本
3.seata-server-0.9.0.zip解壓到指定目錄並修改conf目錄下的file.conf配置文件
先備份原始file.conf文件
主要修改:自定義事務組名稱+事務日志存儲模式為db+數據庫連接
file.conf
service模塊
store模塊
4.mysql5.7數據庫新建庫seata
5.在seata庫里新建表
建表db_store.sql在seata-server-0.9.0\seata\conf目錄里面
db_store.sql
SQL
-- 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目錄下的registry.conf目錄下的registry.conf配置文件
7.先啟動Nacos端口號8848
8.再啟動seata-server
seata-server-0.9.0\seata\bin
seata-server.bat
訂單/庫存/賬戶業務數據庫准備
以下演示都需要先啟動Nacos后啟動Seata,保證兩個都OK
Seata沒啟動報錯no available server to connect
分布式事務業務說明
這里我們會創建三個服務, 一個訂單服務, 一個庫存服務, 一個賬戶服務。
當用戶下單時,會在訂單服務中創建一個訂單 ,然后通過遠程調用庫存服務來扣減下單商品的庫存,
再通過遠程調用賬戶服務來扣減用戶賬戶里面的余額,
最后在訂單服務中修改訂單狀態為已完成。
該操作跨越三個數據庫,有兩次遠程調用,很明顯會有分布式事務問題。
創建業務數據庫
seata_order:存儲訂單的數據庫
seata_storage:存儲庫存的數據庫
seata_account:存儲賬戶信息的數據庫
建表SQL
create database seata_order;
create database seata_storage;
create database seata_account;
按照上述3庫分別建立對應業務表
seata_order庫下新建t_order表
DROP TABLE IF EXISTS `t_order`;
CREATE TABLE `t_order` (
`int` bigint(11) NOT NULL AUTO_INCREMENT,
`user_id` bigint(20) DEFAULT NULL COMMENT '用戶id',
`product_id` bigint(11) DEFAULT NULL COMMENT '產品id',
`count` int(11) DEFAULT NULL COMMENT '數量',
`money` decimal(11, 0) DEFAULT NULL COMMENT '金額',
`status` int(1) DEFAULT NULL COMMENT '訂單狀態: 0:創建中 1:已完結',
PRIMARY KEY (`int`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci COMMENT = '訂單表' ROW_FORMAT = Dynamic;
seata_storage庫下新建t_storage表
DROP TABLE IF EXISTS `t_storage`;
CREATE TABLE `t_storage` (
`int` bigint(11) NOT NULL AUTO_INCREMENT,
`product_id` bigint(11) DEFAULT NULL COMMENT '產品id',
`total` int(11) DEFAULT NULL COMMENT '總庫存',
`used` int(11) DEFAULT NULL COMMENT '已用庫存',
`residue` int(11) DEFAULT NULL COMMENT '剩余庫存',
PRIMARY KEY (`int`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci COMMENT = '庫存' ROW_FORMAT = Dynamic;
INSERT INTO `t_storage` VALUES (1, 1, 100, 0, 100);
seata_account庫下新建t_account表
CREATE TABLE `t_account` (
`id` bigint(11) NOT NULL COMMENT 'id',
`user_id` bigint(11) DEFAULT NULL COMMENT '用戶id',
`total` decimal(10, 0) DEFAULT NULL COMMENT '總額度',
`used` decimal(10, 0) DEFAULT NULL COMMENT '已用余額',
`residue` decimal(10, 0) DEFAULT NULL COMMENT '剩余可用額度',
PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci COMMENT = '賬戶表' ROW_FORMAT = Dynamic;
INSERT INTO `t_account` VALUES (1, 1, 1000, 0, 1000);
按照上述3庫分別建立對應的回滾日志表
訂單-庫存-賬戶3個庫下都需要建各自獨立的回滾日志表
seata-server-0.9.0\seata\conf\目錄下的db_undo_log.sql
建表SQL
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;
最終效果
訂單/庫存/賬戶業務微服務准備
業務需求
下訂單->減庫存->扣余額->改(訂單)狀態
新建訂單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>
<groupId>io.seata</groupId>
<artifactId>seata-all</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>io.seata</groupId>
<artifactId>seata-all</artifactId>
<version>0.9.0</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!--jdbc-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!--hutool 測試雪花算法-->
<dependency>
<groupId>cn.hutool</groupId>
<artifactId>hutool-captcha</artifactId>
<version>5.2.0</version>
</dependency>
</dependencies>
3.YML
server:
port: 2001
spring:
application:
name: seata-order-service
cloud:
alibaba:
seata:
# 自定義事務組名稱需要與seata-server中的對應
tx-service-group: fsp_tx_group
nacos:
discovery:
server-addr: 127.0.0.1:8848
datasource:
# 當前數據源操作類型
type: com.alibaba.druid.pool.DruidDataSource
# mysql驅動類
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/seata_order?useUnicode=true&characterEncoding=UTF-8&useSSL=false&serverTimezone=GMT%2B8
username: root
password: root
feign:
hystrix:
enabled: false
logging:
level:
io:
seata: info
mybatis:
mapperLocations: classpath*:mapper/*.xml
4.file.conf
就是seata文件夾下的file.conf
拷貝seata-server/conf目錄下的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 {
#vgroup->rgroup
# 事務組名稱
vgroup_mapping.fsp_tx_group = "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 = "file"
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
}
}
5.registry.conf
拷貝seata-server/conf目錄下的registry.conf
registry {
# file 、nacos 、eureka、redis、zk、consul、etcd3、sofa
type = "nacos"
nacos {
#serverAddr = "localhost"
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
@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
7.Dao接口實現
OrderDao
@Mapper
public interface OrderDao {
/**
* 1 新建訂單
* @param order
* @return
*/
int create(Order order);
/**
* 2 修改訂單狀態,從0改為1
* @param userId
* @param status
* @return
*/
int update(@Param("userId") Long userId, @Param("status") Integer status);
}
resources文件夾下新建mapper文件夾后添加
<?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.eiletxie.springcloud.alibaba.dao.OrderDao">
<resultMap id="BaseResultMap" type="com.eiletxie.springcloud.alibaba.domain.Order">
<id column="id" property="id" jdbcType="BIGINT"></id>
<result column="user_id" property="userId" jdbcType="BIGINT"></result>
<result column="product_id" property="productId" jdbcType="BIGINT"></result>
<result column="count" property="count" jdbcType="INTEGER"></result>
<result column="money" property="money" jdbcType="DECIMAL"></result>
<result column="status" property="status" jdbcType="INTEGER"></result>
</resultMap>
<insert id="create" parameterType="com.eiletxie.springcloud.alibaba.domain.Order" useGeneratedKeys="true"
keyProperty="id">
insert into t_order(user_id,product_id,count,money,status) values (#{userId},#{productId},#{count},#{money},0);
</insert>
<update id="update">
update t_order set status =1 where user_id =#{userId} and status=#{status};
</update>
</mapper>
OrderMapper.xml
8.Service接口及實現
OrderService
public interface OrderService {
/**
* 創建訂單
* @param order
*/
void create(Order order);
}
@Service
@Slf4j
public class OrderServiceImpl implements OrderService {
@Resource
private OrderDao orderDao;
@Resource
private AccountService accountService;
@Resource
private StorageService storageService;
/**
* 創建訂單->調用庫存服務扣減庫存->調用賬戶服務扣減賬戶余額->修改訂單狀態
* 簡單說:
* 下訂單->減庫存->減余額->改狀態
* GlobalTransactional seata開啟分布式事務,異常時回滾,name保證唯一即可
* @param order 訂單對象
*/
@Override
///@GlobalTransactional(name = "fsp-create-order", rollbackFor = Exception.class)
public void create(Order order) {
// 1 新建訂單
log.info("----->開始新建訂單");
orderDao.create(order);
// 2 扣減庫存
log.info("----->訂單微服務開始調用庫存,做扣減Count");
storageService.decrease(order.getProductId(), order.getCount());
log.info("----->訂單微服務開始調用庫存,做扣減End");
// 3 扣減賬戶
log.info("----->訂單微服務開始調用賬戶,做扣減Money");
accountService.decrease(order.getUserId(), order.getMoney());
log.info("----->訂單微服務開始調用賬戶,做扣減End");
// 4 修改訂單狀態,從0到1,1代表已完成
log.info("----->修改訂單狀態開始");
orderDao.update(order.getUserId(), 0);
log.info("----->下訂單結束了,O(∩_∩)O哈哈~");
}
}
AccountService
@FeignClient(value = "seata-account-service")
public interface AccountService {
/**
* 減余額
* @param userId
* @param money
* @return
*/
@PostMapping(value = "/account/decrease")
CommonResult decrease(@RequestParam("userId") Long userId, @RequestParam("money") BigDecimal money);
}
StorageService
@FeignClient(value = "seata-storage-service")
public interface StorageService {
/**
* 減庫存
* @param productId
* @param count
* @return
*/
@PostMapping(value = "/storage/decrease")
CommonResult decrease(@RequestParam("productId") Long productId, @RequestParam("count") Integer count);
}
9.Controller
OrderController
@RestController
public class OrderController {
@Resource
private OrderService orderService;
/**
* 創建訂單
*
* @param order
* @return
*/
@GetMapping("/order/create")
public CommonResult create(Order order) {
orderService.create(order);
return new CommonResult(200, "訂單創建成功");
}
}
10.Config配置
MyBatisConfig
@Configuration
@MapperScan({"com.eiletxie.springcloud.alibaba.dao"})
public class MyBatisConfig {
}
DataSourceProxyConfig
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.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 org.springframework.core.io.support.ResourcePatternResolver;
import javax.sql.DataSource;
/**
* @Author EiletXie
* @Since 2020/3/18 21:51
* 使用Seata對數據源進行代理
*/
@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 druidDataSource) {
return new DataSourceProxy(druidDataSource);
}
@Bean
public SqlSessionFactory sqlSessionFactoryBean(DataSourceProxy dataSourceProxy) throws Exception {
SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
bean.setDataSource(dataSourceProxy);
ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
bean.setMapperLocations(resolver.getResources(mapperLocations));
return bean.getObject();
}
}
11.主啟動
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class) //取消數據源的自動創建
@EnableDiscoveryClient
@EnableFeignClients
public class SeataOrderMain2001 {
public static void main(String[] args) {
SpringApplication.run(SeataOrderMain2001.class,args);
}
}
新建庫存Storage-Module
1、seata-storage-service2002
基本和2001一樣,除了dao層和mapper有點區別
2、POM
3、YML
server:
port: 2002
spring:
application:
name: seata-storage-service
cloud:
alibaba:
seata:
tx-service-group: fsp_tx_group
nacos:
discovery:
server-addr: localhost:8848
datasource:
type: com.alibaba.druid.pool.DruidDataSource
# mysql驅動類
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/seata_storage?useUnicode=true&characterEncoding=UTF-8&useSSL=false&serverTimezone=GMT%2B8
username: root
password: root
feign:
hystrix:
enabled: false
logging:
level:
io:
seata: info
mybatis:
mapperLocations: classpath*:mapper/*.xml
4、file.conf
5、registry.conf
6、domain
CommonResult
和2001一樣
Storage
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Storage {
private Long id;
private Integer total;
private Integer used;
private Integer residue;
}
7、Dao接口及實現
StorageDao
@Mapper
public interface StorageDao {
void decrease(@Param("productId") Long productId,@Param("count") Integer count);
}
resources文件夾下新建mapper文件夾后添加
<?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.eiletxie.springcloud.alibaba.dao.StorageDao">
<resultMap id="BaseResultMap" type="com.eiletxie.springcloud.alibaba.domain.Storage">
<id column="id" property="id" jdbcType="BIGINT"></id>
<result column="product_id" property="productId" jdbcType="BIGINT"></result>
<result column="total" property="total" jdbcType="INTEGER"></result>
<result column="used" property="used" jdbcType="INTEGER"></result>
<result column="residue" property="residue" jdbcType="INTEGER"></result>
</resultMap>
<update id="decrease">
update t_storage
set used = used + #{count},residue = residue - #{count}
where product_id= #{productId};
</update>
</mapper>
8、Service接口及實現
StorageService
public interface StorageService {
void decrease(Long productId, Integer count);
}
StorageServiceImpl
@Service
public class StorageServiceImpl implements StorageService {
private static final Logger LOGGER = LoggerFactory.getLogger(StorageServiceImpl.class);
@Resource
private StorageDao storageDao;
@Override
public void decrease(Long productId, Integer count) {
LOGGER.info("----> storage-service中扣減庫存開始");
storageDao.decrease(productId,count);
LOGGER.info("----> storage-service中扣減庫存結束");
}
}
9、Controller
StorageController
@RestController
public class StorageController {
@Resource
private StorageService storageService;
@RequestMapping("/storage/decrease")
public CommonResult decrease(Long productId,Integer count) {
storageService.decrease(productId, count);
return new CommonResult(200,"扣減庫存成功!");
}
}
10、Config配置
和2001一樣
11、主啟動
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
@EnableFeignClients
@EnableDiscoveryClient
public class SeataStorageMain2002 {
public static void main(String[] args) {
SpringApplication.run(SeataStorageMain2002.class,args);
}
}
新建賬戶Account-Module
1、seata-account-service2003
6、domain
CommonResult
和2001一樣
Account
7、Dao接口及實現
AccountDao
@Mapper
public interface AccountDao {
/**
* 扣減賬戶余額
* @param userId
* @param money
*/
void decrease(@Param("userId") Long userId, @Param("money") BigDecimal money);
}
resources文件夾下新建mapper文件夾后添加
<?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.eiletxie.springcloud.alibaba.dao.AccountDao">
<resultMap id="BaseResultMap" type="com.eiletxie.springcloud.alibaba.domain.Account">
<id column="id" property="id" jdbcType="BIGINT"></id>
<result column="user_id" property="userId" jdbcType="BIGINT"></result>
<result column="total" property="total" jdbcType="DECIMAL"></result>
<result column="used" property="used" jdbcType="DECIMAL"></result>
<result column="residue" property="residue" jdbcType="DECIMAL"></result>
</resultMap>
<update id="decrease">
update t_account
set used = used + #{money},residue = residue - #{money}
where user_id= #{userId};
</update>
</mapper>
8、Service接口及實現
AccountService
public interface AccountService {
void decrease(Long userId, BigDecimal money);
}
AccountServiceImpl
@Service
public class AccountServiceImpl implements AccountService {
private static final Logger LOGGER = LoggerFactory.getLogger(AccountServiceImpl.class);
@Resource
private AccountDao accountDao;
@Override
public void decrease(Long userId, BigDecimal money) {
LOGGER.info("----> account-service中扣減用戶余額開始");
accountDao.decrease(userId,money);
LOGGER.info("----> account-service中扣減用戶余額開始");
}
}
9、Controller
AccountController
@RestController
public class AccountController {
@Resource
AccountService accountService;
@RequestMapping("/account/decrease")
public CommonResult decrease(@RequestParam("userId") Long userId,@RequestParam("money") BigDecimal money) {
accountService.decrease(userId,money);
return new CommonResult(200,"扣減賬戶余額成功!");
}
}
11、主啟動
@SpringBootApplication(exclude = DataSourceAutoConfiguration.class)
@EnableFeignClients
@EnableDiscoveryClient
public class SeataAccountMain2003 {
public static void main(String[] args) {
SpringApplication.run(SeataAccountMain2003.class,args);
}
}
YML
server:
port: 2003
spring:
application:
name: seata-account-service
cloud:
alibaba:
seata:
tx-service-group: fsp_tx_group
nacos:
discovery:
server-addr: localhost:8848
datasource:
type: com.alibaba.druid.pool.DruidDataSource
# mysql驅動類
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/seata_account?useUnicode=true&characterEncoding=UTF-8&useSSL=false&serverTimezone=GMT%2B8
username: root
password: root
feign:
hystrix:
enabled: false
logging:
level:
io:
seata: info
mybatis:
mapperLocations: classpath*:mapper/*.xml
Test
數據庫初始情況
下訂單->減庫存->扣余額->改訂單狀態
正常下單
http://localhost:2001/order/create?userId=1&productId=1&count=10&money=100
數據庫情況
超時異常,沒加@GlobalTransational
- AccountServiceImpl添加超時
- 數據庫情況
- 故障情況
- 當庫存和賬戶金額扣減后,訂單狀態並沒有設置為依據完成,沒有從零改為1
- 而且由於feign的重試機制,賬戶余額還有可能被多次扣減
超時異常,添加@GlobalTransational
結果
各數據庫無記錄新增
OrderServiceImpl
@Override
@GlobalTransactional(name = "fsp-create-order",rollbackFor = Exception.class)
///@GlobalTransactional(name = "fsp-create-order", rollbackFor = Exception.class)
public void create(Order order) {
// 1 新建訂單
log.info("----->開始新建訂單");
orderDao.create(order);
// 2 扣減庫存
log.info("----->訂單微服務開始調用庫存,做扣減Count");
storageService.decrease(order.getProductId(), order.getCount());
log.info("----->訂單微服務開始調用庫存,做扣減End");
// 3 扣減賬戶
log.info("----->訂單微服務開始調用賬戶,做扣減Money");
accountService.decrease(order.getUserId(), order.getMoney());
log.info("----->訂單微服務開始調用賬戶,做扣減End");
// 4 修改訂單狀態,從0到1,1代表已完成
log.info("----->修改訂單狀態開始");
orderDao.update(order.getUserId(), 0);
log.info("----->下訂單結束了,O(∩_∩)O哈哈~");
}
一部分補充
Seata
- 2019年1月份螞蟻金服和阿里巴巴共同開源的分布式事務解決方案
- Simple Extensible Autonomous Transaction Architecture ,簡單可擴展自治事務框架
- 2020起始,參加工作后使用1.0以后的版本
再看TC/TM/RM三大組件
分布式事務的執行流程
- TM開啟分布式事務(TM向TC注冊全局事務記錄)
- 按業務場景,編排數據庫、服務等事務內資源(RM向TC匯報資源准備狀態)
- TM結束分布式事務,事務一階段結束(TM通知TC提交/回滾分布式事務)
- TC匯總事務信息,決定分布式事務是提交還是回滾
- TC通知所有RM提交/回滾 資源,事務二階段結束
AT模式如何做到對業務的無侵入
是什么
一階段加載
二階段提交
二階段回滾
debug
AccountServiceImpl
undo.log
before image
補充