让我们从一个微服务示例开始。
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:
public interface StorageService {
/**
* 扣除存储数量
*/
void deduct(String commodityCode, int count);
}
public interface OrderService {
/**
* 创建订单
*/
Order create(String userId, String commodityCode, int orderCount);
}
public interface AccountService {
/**
* 从用户账户中借出
*/
void debit(String userId, int money);
}
public class BusinessServiceImpl implements BusinessService {
private StorageService storageService;
private OrderService orderService;
/**
* 采购
*/
public void purchase(String userId, String commodityCode, int orderCount) {
storageService.deduct(commodityCode, orderCount);
orderService.create(userId, commodityCode, orderCount);
}
}
public class OrderServiceImpl implements OrderService {
private OrderDAO orderDAO;
private AccountService accountService;
public Order create(String userId, String commodityCode, int orderCount) {
int orderMoney = calculate(commodityCode, orderCount);
accountService.debit(userId, orderMoney);
Order order = new Order();
order.userId = userId;
order.commodityCode = commodityCode;
order.count = orderCount;
order.money = orderMoney;
// INSERT INTO orders ...
return orderDAO.insert(order);
}
}
我们只需要使用一个
@GlobalTransactional
注解在业务方法上:
@GlobalTransactional
public void purchase(String userId, String commodityCode, int orderCount) {
......
}
注意: 实际上,在示例用例中,这3个服务应该有3个数据库。 但是,为了简单起见,我们只创建一个数据库并配置3个数据源。
使用您刚创建的数据库 URL/username/password 修改Spring XML。
dubbo-account-service.xml dubbo-order-service.xml dubbo-storage-service.xml
<property name="url" value="jdbc:mysql://x.x.x.x:3306/xxx" />
<property name="username" value="xxx" />
<property name="password" value="xxx" />
SEATA AT 模式需要 UNDO_LOG
表
-- 注意此处0.3.0+ 增加唯一索引 ux_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;
DROP TABLE IF EXISTS `storage_tbl`;
CREATE TABLE `storage_tbl` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`commodity_code` varchar(255) DEFAULT NULL,
`count` int(11) DEFAULT 0,
PRIMARY KEY (`id`),
UNIQUE KEY (`commodity_code`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
DROP TABLE IF EXISTS `order_tbl`;
CREATE TABLE `order_tbl` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`user_id` varchar(255) DEFAULT NULL,
`commodity_code` varchar(255) DEFAULT NULL,
`count` int(11) DEFAULT 0,
`money` int(11) DEFAULT 0,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
DROP TABLE IF EXISTS `account_tbl`;
CREATE TABLE `account_tbl` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`user_id` varchar(255) DEFAULT NULL,
`money` int(11) DEFAULT 0,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
Usage: sh seata-server.sh(for linux and mac) or cmd seata-server.bat(for windows) [options]
Options:
--host, -h
The address is expose to registration center and other service can access seata-server via this ip
Default: 0.0.0.0
--port, -p
The port to listen.
Default: 8091
--storeMode, -m
log store mode : file、db
Default: file
--help
e.g.
sh seata-server.sh -p 8091 -h 127.0.0.1 -m file
示例仓库: seata-samples
TBD: 运行演示应用程序的脚本