diff --git a/dtmcli/types.go b/dtmcli/types.go
new file mode 100644
index 0000000..7b88b45
--- /dev/null
+++ b/dtmcli/types.go
@@ -0,0 +1,30 @@
+package dtmcli
+
+import (
+	"fmt"
+
+	"github.com/yedf/dtm/common"
+)
+
+func GenGid(server string) string {
+	res := common.MS{}
+	_, err := common.RestyClient.R().SetResult(&res).Get(server + "/newGid")
+	e2p(err)
+	return res["gid"]
+}
+
+type IDGenerator struct {
+	parentID string
+	branchID int
+}
+
+func (g *IDGenerator) NewBranchID() string {
+	if g.branchID >= 99 {
+		panic(fmt.Errorf("branch id is larger than 99"))
+	}
+	if len(g.parentID) >= 20 {
+		panic(fmt.Errorf("total branch id is longer than 20"))
+	}
+	g.branchID = g.branchID + 1
+	return g.parentID + fmt.Sprintf("%02d", g.branchID)
+}