check

controllers/api_controller.go

@@ -38,6 +38,9 @@ const (
 	keyOrderNo  = "order_no"
 	keyContent  = "content"
 	keyMsgID    = "msg_id"
+	keySound    = "sound"
+	keyVolume   = "volume"
+	keySim      = "sim"
 )
 
 var (
@@ -265,17 +268,17 @@ func (c *ApiController) UpdatePrinter(dataMap map[string]interface{}) (data, err
 	} else {
 		name = &nameStr
 	}
-	if simStr, ok := dataMap["sim"].(string); !ok {
+	if simStr, ok := dataMap[keySim].(string); !ok {
 		sim = nil
 	} else {
 		sim = &simStr
 	}
-	if soundStr, ok := dataMap["sound"].(string); !ok {
+	if soundStr, ok := dataMap[keySound].(string); !ok {
 		sound = nil
 	} else {
 		sound = &soundStr
 	}
-	if volumeInt, ok := dataMap["volume"].(int); !ok {
+	if volumeInt, ok := dataMap[keyVolume].(int); !ok {
 		volume = nil
 	} else {
 		volume = &volumeInt