保姆级教程：Spring Cloud 集成Seata分布式事务

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环境搭建

Nacos搭建

最新版本快速搭建 使用Mysql模式

Nacos直接启动即可。控制台默认账号密码是nacos/nacos，Mysql账户密码有两个 root/root 和 nacos/nacos。

Seata搭建

Seata版本1.5.0 快速搭建

Seata1.5.0版本直接是一个SpringBoot项目，下载后修改application.yml 文件中注册中心、配置中心、存储模式配置。参考resources/application.example.yml 文件 ，修改后如下

server:
port:7091

spring:
application:
name:seata-server

logging:
config:classpath:logback-spring.xml
file:
path:${user.home}/logs/seata
extend:
logstash-appender:
destination:127.0.0.1:4560
kafka-appender:
bootstrap-servers:127.0.0.1:9092
topic:logback_to_logstash

console:
user:
username:seata
password:seata

seata:
config:
#support:nacos,consul,apollo,zk,etcd3
type:file
registry:
#support:nacos,eureka,redis,zk,consul,etcd3,sofa
type:nacos
nacos:
application:seata-server
server-addr:127.0.0.1:8848
namespace:
group:SEATA_GROUP
cluster:default
username:nacos
password:nacos
##ifuseMSENacoswithauth,mutexwithusername/passwordattribute
#access-key:""
#secret-key:""
store:
#support:file、db、redis
mode:db
db:
datasource:druid
db-type:mysql
driver-class-name:com.mysql.jdbc.Driver
url:jdbc//127.0.0.1:3306/seata?rewriteBatchedStatements=true
user:root
password:root
min-conn:5
max-conn:100
global-table:global_table
branch-table:branch_table
lock-table:lock_table
distributed-lock-table:distributed_lock
query-limit:100
max-wait:5000

>基于SpringBoot+MyBatisPlus+Vue&Element实现的后台管理系统+用户小程序，支持RBAC动态权限、多租户、数据权限、工作流、三方登录、支付、短信、商城等功能
>
>*项目地址：
>*视频教程：

#server:

>基于SpringCloudAlibaba+Gateway+Nacos+RocketMQ+Vue&Element实现的后台管理系统+用户小程序，支持RBAC动态权限、多租户、数据权限、工作流、三方登录、支付、短信、商城等功能
>
>*项目地址：
>*视频教程：

#service-port:8091#Ifnotconfigured,thedefaultis'${server.port}+1000'
security:
secretKey:SeataSecretKey0c382ef121d778043159209298fd40bf3850a017
tokenValidityInMilliseconds:1800000
ignore:
urls:/,/**/*.css,/**/*.js,/**/*.html,/**/*.map,/**/*.svg,/**/*.png,/**/*.ico,/console-fe/public/**,/api/v1/auth/login

创建seata数据库，执行脚本建表

----------------------------------ThescriptusedwhenstoreModeis'db'--------------------------------
--thetabletostoreGlobalSessiondata
CREATETABLEIFNOTEXISTS`global_table`
(
`xid`VARCHAR(128)NOTNULL,
`transaction_id`BIGINT,
`status`TINYINTNOTNULL,
`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,
PRIMARYKEY(`xid`),
KEY`idx_status_gmt_modified`(`status`,`gmt_modified`),
KEY`idx_transaction_id`(`transaction_id`)
)ENGINE=InnoDB
DEFAULTCHARSET=utf8mb4;

--thetabletostoreBranchSessiondata
CREATETABLEIFNOTEXISTS`branch_table`
(
`branch_id`BIGINTNOTNULL,
`xid`VARCHAR(128)NOTNULL,
`transaction_id`BIGINT,
`resource_group_id`VARCHAR(32),
`resource_id`VARCHAR(256),
`branch_type`VARCHAR(8),
`status`TINYINT,
`client_id`VARCHAR(64),
`application_data`VARCHAR(2000),
`gmt_create`DATETIME(6),
`gmt_modified`DATETIME(6),
PRIMARYKEY(`branch_id`),
KEY`idx_xid`(`xid`)
)ENGINE=InnoDB
DEFAULTCHARSET=utf8mb4;

--thetabletostorelockdata
CREATETABLEIFNOTEXISTS`lock_table`
(
`row_key`VARCHAR(128)NOTNULL,
`xid`VARCHAR(128),
`transaction_id`BIGINT,
`branch_id`BIGINTNOTNULL,
`resource_id`VARCHAR(256),
`table_name`VARCHAR(32),
`pk`VARCHAR(36),
`status`TINYINTNOTNULLDEFAULT'0'COMMENT'0:locked,1:rollbacking',
`gmt_create`DATETIME,
`gmt_modified`DATETIME,
PRIMARYKEY(`row_key`),
KEY`idx_status`(`status`),
KEY`idx_branch_id`(`branch_id`),
KEY`idx_xid`(`xid`)
)ENGINE=InnoDB
DEFAULTCHARSET=utf8mb4;

CREATETABLEIFNOTEXISTS`distributed_lock`
(
`lock_key`CHAR(20)NOTNULL,
`lock_value`VARCHAR(20)NOTNULL,
`expire`BIGINT,
primarykey(`lock_key`)
)ENGINE=InnoDB
DEFAULTCHARSET=utf8mb4;

INSERTINTO`distributed_lock`(lock_key,lock_value,expire)VALUES('AsyncCommitting','',0);
INSERTINTO`distributed_lock`(lock_key,lock_value,expire)VALUES('RetryCommitting','',0);
INSERTINTO`distributed_lock`(lock_key,lock_value,expire)VALUES('RetryRollbacking','',0);
INSERTINTO`distributed_lock`(lock_key,lock_value,expire)VALUES('TxTimeoutCheck','',0);

启动seata-server，控制台登录页面如下，账号密码为seata/seata。

项目搭建

业务背景

用户购买商品的业务逻辑。整个业务逻辑由3个微服务提供支持：

• 仓储服务： 对给定的商品扣除仓储数量。
• 订单服务： 根据采购需求创建订单。
• 帐户服务： 从用户帐户中扣除余额。

架构

业务表创建

------------------------------
--Tablestructurefort_account
------------------------------
DROPTABLEIFEXISTS`t_account`;
CREATETABLE`t_account`
(
`id`int(11)NOTNULLAUTO_INCREMENT,
`user_id`varchar(255)DEFAULTNULL,
`amount`double(14,2
)DEFAULT'0.00',
PRIMARYKEY(`id`)
)ENGINE=InnoDBAUTO_INCREMENT=2DEFAULTCHARSET=utf8;

------------------------------
--Recordsoft_account
------------------------------
INSERTINTO`t_account`
VALUES('1','1','4000.00');

------------------------------
--Tablestructurefort_order
------------------------------
DROPTABLEIFEXISTS`t_order`;
CREATETABLE`t_order`
(
`id`int(11)NOTNULLAUTO_INCREMENT,
`order_no`varchar(255)DEFAULTNULL,
`user_id`varchar(255)DEFAULTNULL,
`commodity_code`varchar(255)DEFAULTNULL,
`count`int(11)DEFAULT'0',
`amount`double(14,2
)DEFAULT'0.00',
PRIMARYKEY(`id`)
)ENGINE=InnoDBAUTO_INCREMENT=64DEFAULTCHARSET=utf8;

------------------------------
--Recordsoft_order
------------------------------

------------------------------
--Tablestructurefort_stock
------------------------------
DROPTABLEIFEXISTS`t_stock`;
CREATETABLE`t_stock`
(
`id`int(11)NOTNULLAUTO_INCREMENT,
`commodity_code`varchar(255)DEFAULTNULL,
`name`varchar(255)DEFAULTNULL,
`count`int(11)DEFAULT'0',
PRIMARYKEY(`id`),
UNIQUEKEY`commodity_code`(`commodity_code`)
)ENGINE=InnoDBAUTO_INCREMENT=2DEFAULTCHARSET=utf8;

------------------------------
--Recordsoft_stock
------------------------------
INSERTINTO`t_stock`
VALUES('1','C201901140001','水杯','1000');

------------------------------
--Tablestructureforundo_log
--注意此处0.3.0+增加唯一索引ux_undo_log
------------------------------
DROPTABLEIFEXISTS`undo_log`;
CREATETABLE`undo_log`
(
`id`bigint(20)NOTNULLAUTO_INCREMENT,
`branch_id`bigint(20)NOTNULL,
`xid`varchar(100)NOTNULL,
`context`varchar(128)NOTNULL,
`rollback_info`longblobNOTNULL,
`log_status`int(11)NOTNULL,
`log_created`datetimeNOTNULL,
`log_modified`datetimeNOTNULL,
PRIMARYKEY(`id`),
UNIQUEKEY`ux_undo_log`(`xid`,`branch_id`)
)ENGINE=InnoDBAUTO_INCREMENT=1DEFAULTCHARSET=utf8;

------------------------------
--Recordsofundo_log
------------------------------
SET
FOREIGN_KEY_CHECKS=1;

服务创建

业务服务

以order服务为例，引入依赖、配置参数、提供创建订单接口。

pom.xml文件中引入依赖

<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>com.alibaba.cloudgroupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discoveryartifactId>
dependency>
<dependency>
<groupId>com.alibaba.cloudgroupId>
<artifactId>spring-cloud-starter-alibaba-seataartifactId>
dependency>
<dependency>
<groupId>com.alibabagroupId>
<artifactId>druidartifactId>
dependency>
<dependency>
<groupId>com.baomidougroupId>
<artifactId>mybatis-plus-boot-starterartifactId>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
dependency>
dependencies>

application.properties配置参数

server.port=81
spring.application.name=order
spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848
spring.cloud.nacos.username=nacos
spring.cloud.nacos.password=nacos
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc//127.0.0.1:3306/seata_samples?allowPublicKeyRetrieval=true&useSSL=false&useUnicode=true&characterEncoding=utf-8&allowMultiQueries=true
spring.datasource.username=root
spring.datasource.password=root
mybatis-plus.mapper-locations=classpath:mapper/*.xml
mybatis-plus.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl

提供创建订单接口

@RequestMapping("/add")
publicvoidadd(StringuserId,StringcommodityCode,Integercount,BigDecimalamount){
Orderorder=newOrder();
order.setOrderNo(UUID.randomUUID().toString());
order.setUserId(userId);
order.setAmount(amount);
order.setCommodityCode(commodityCode);
order.setCount(count);
orderService.save(order);
}

聚合服务

business服务远程调用仓储、订单、帐户服务，完成下单流程。

1.pom.xml文件中引入依赖

<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-webartifactId>
dependency>
<dependency>
<groupId>com.alibaba.cloudgroupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discoveryartifactId>
dependency>
<dependency>
<groupId>com.alibaba.cloudgroupId>
<artifactId>spring-cloud-starter-alibaba-seataartifactId>
dependency>
<dependency>
<groupId>com.alibabagroupId>
<artifactId>druidartifactId>
dependency>
<dependency>
<groupId>org.springframework.cloudgroupId>
<artifactId>spring-cloud-starter-openfeignartifactId>
dependency>
dependencies>

2.application.properties配置参数

server.port=80
spring.application.name=business
spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848
spring.cloud.nacos.username=nacos
spring.cloud.nacos.password=nacos
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc//127.0.0.1:3306/seata_samples?allowPublicKeyRetrieval=true&useSSL=false&useUnicode=true&characterEncoding=utf-8&allowMultiQueries=true
spring.datasource.username=root
spring.datasource.password=root
service.disableGlobalTransaction=false
# 连接超时时间
ribbon.ConnectTimeout=3000
# 响应超时时间
ribbon.ReadTimeout=5000

3.声明account、stock、order的feign接口。

@FeignClient(value="account")
publicinterfaceAccountFeign{
@RequestMapping("/account/reduce")
publicvoidreduce(@RequestParam("userId")StringuserId,@RequestParam("amount")BigDecimalamount);

}
@FeignClient(value="order")
publicinterfaceOrderFeign{
@RequestMapping("/order/add")
publicvoidadd(@RequestParam("userId")StringuserId,@RequestParam("commodityCode")StringcommodityCode,@RequestParam("count")Integercount,@RequestParam("amount")BigDecimalamount);

}
@FeignClient(value="stock")
publicinterfaceStockFeign{
@RequestMapping("/stock/deduct")
publicvoiddeduct(@RequestParam("commodityCode")StringcommodityCode,@RequestParam("count")Integercount);

}

4.全局事务开启，调用feign接口

@Autowired
privateOrderFeignorderFeign;

@Autowired
privateStockFeignstockFeign;

@Autowired
privateAccountFeignaccountFeign;

@GlobalTransactional
@RequestMapping("/toOrder")
publicvoidtoOrder(StringuserId,StringcommodityCode,Integercount,BigDecimalamount){
accountFeign.reduce(userId,amount);
stockFeign.deduct(commodityCode,count);
orderFeign.add(userId,commodityCode,count,amount);
}

测试验证

当前资金账户4000，库存1000，模拟用户购买商品2000个，消费4000，业务调用后，数据库数据状态应该如下：

• 用户资金满足4000，数据库更新用户资金为0。
• 商品库存不满足2000个，异常。
• business服务提交全局回滚。
• 资金服务回滚操作，更新资金为4000。

验证：

1.浏览器输入地址请求访问

• http://127.0.0.1/business/toOrder?userId=1&commodityCode=C201901140001&count=2000&amount=4000

2.account、stock服务日志观察。

3.数据库数据依然为原始状态。

注意事项

1.Seata1.5版本的mysql驱动是5.7，需要为8，在libs文件夹删除mysql-connector-java-5.xx.jar，替换mysql-connector-java-8.xx.jar即可

2.Spring Boot &Spring Cloud&Spring Cloud Alibaba版本兼容问题

Spring Cloud Alibaba版本说明

3.druid和数据驱动版本兼容

通过druid仓库版本查看各依赖版本说明

代码仓库

• https://gitee.com/codeWBG/springcloud_alibaba