fixed ifelse logic fault

handler/diag.go

@@ -10,12 +10,13 @@ import (
 func Dhandler(w http.ResponseWriter, r *http.Request) {
 	var diagnostics pkg.Diag
 
-	if err := pkg.GetDiag(&diagnostics); err != nil {
-		http.Error(w, "An error occurred", http.StatusBadGateway)
-	}
-
+	err := pkg.GetDiag(&diagnostics)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusBadGateway)
+	} else {
 		w.Header().Set("Content-Type", "application/json")
 		if err := json.NewEncoder(w).Encode(&diagnostics); err != nil {
 			log.Fatal(err)
 		}
+	}
 }