# golang dtm server

git clone https://github.com/dtm-labs/dtm && cd dtm
go run main.go


git clone https://github.com/dtm-labs/dtmcli-go-sample && cd dtmcli-go-sample
go run main.go

// QsFireRequest quick start: fire request
func QsFireRequest() string {
	fmt.Println(mount)
	req := &gin.H{"amount": 30} // 微服務的載荷
	// DtmServer為DTM服務的地址
	saga := dtmcli.NewSaga(dtmServer, dtmcli.MustGenGid(dtmServer)).
		// 添加一個TransOut的子事務，正向操作為url: qsBusi+"/TransOut"， 逆向操作為url: qsBusi+"/TransOutCompensate"
		Add(qsBusi+"/TransOut", qsBusi+"/TransOutCompensate", req).
		// 添加一個TransIn的子事務，正向操作為url: qsBusi+"/TransOut"， 逆向操作為url: qsBusi+"/TransInCompensate"
		Add(qsBusi+"/TransIn", qsBusi+"/TransInCompensate", req)
	// 提交saga事務，dtm會完成所有的子事務/回滾所有的子事務
	err := saga.Submit()
	logger.FatalIfError(err)
	return saga.Gid
} 

var mount = 30
func qsAddRoute(app *gin.Engine) {

	app.POST(qsBusiAPI+"/TransIn", func(c *gin.Context) {
		logger.Infof("TransIn")
		// c.JSON(200, "")
		mount += 60
		fmt.Println(mount)
		c.JSON(409, "") // Status 409 for Failure. Won't be retried
	})
	app.POST(qsBusiAPI+"/TransInCompensate", func(c *gin.Context) {
		logger.Infof("TransInCompensate")
		mount -= 60
		fmt.Println(mount)
		c.JSON(200, "")
	})
	app.POST(qsBusiAPI+"/TransOut", func(c *gin.Context) {
		logger.Infof("TransOut")
		mount -= 20
		fmt.Println(mount)
		c.JSON(200, "")
	})
	app.POST(qsBusiAPI+"/TransOutCompensate", func(c *gin.Context) {
		logger.Infof("TransOutCompensate")
		mount += 20
		fmt.Println(mount)
		c.JSON(200, "")
	})
}

當你的微服務都是http requset 則在

		Add(qsBusi+"/TransOut", qsBusi+"/TransOutCompensate", req).
		// 添加一個TransIn的子事務，正向操作為url: qsBusi+"/TransOut"， 逆向操作為url: qsBusi+"/TransInCompensate"
		Add(qsBusi+"/TransIn", qsBusi+"/TransInCompensate", req)

要確保這部分的業務邏輯一定要對否則rollback

	app.POST(qsBusiAPI+"/TransIn", func(c *gin.Context) {
		logger.Infof("TransIn")
		// c.JSON(200, "")
		mount += 60
		fmt.Println(mount)
		c.JSON(409, "") // Status 409 for Failure. Won't be retried
	})

可以看到最終值可以維持不變