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middleware/check/check.go

 			}
 
 			if !ew.successful() {
+				// 对返回的错误信息格式进行代码检测
 				if len(rps) != 1 || rps["msg"] == "" {
 					panic(fmt.Sprintf("you need return %s but, %s", `{"msg":"content can't empty'"}`, string(ew.data)))
 				}