- make gorm.DB singleton.

globals/gormdb/gormdb.go

@@ -9,7 +9,8 @@ import (
 )
 
 var (
-	dbStr string
+	dbStr       string
+	singletonDB *gorm.DB
 )
 
 func Init() {
@@ -17,12 +18,17 @@ func Init() {
 	AutoMigrate()
 }
 
+// todo gorm要求用单一的db？如果每次重新调用Open，会导致too many connection错误
 func GetDB() *gorm.DB {
-	db, err := gorm.Open("mysql", dbStr)
-	if err == nil {
-		return db
+	if singletonDB == nil {
+		db, err := gorm.Open("mysql", dbStr)
+		if err == nil {
+			singletonDB = db
+			return db
+		}
+		panic(fmt.Sprintf("AutoMigrate failed with error:%v", err))
 	}
-	panic(fmt.Sprintf("AutoMigrate failed with error:%v", err))
+	return singletonDB
 }
 
 func AutoMigrate() {
@@ -38,4 +44,5 @@ func AutoMigrate() {
 	db.AutoMigrate(&model.SkuVendorCategory{}, &model.StoreSkuCategoryMap{}, &model.SkuName{}, &model.Sku{}, &model.SkuNamePlaceBind{}, &model.StoreSkuBind{})
 	db.Set("gorm:table_options", "CHARSET=utf8mb4").AutoMigrate(&model.SkuCategory{})
 	db.AutoMigrate(&model.WeiXins{}, &model.JxBackendUser{})
+	// db.AutoMigrate(&model.DurableTask{}, &model.DurableTaskItem{})
 }