Update app.py

app.py

@@ -64,6 +64,12 @@ def predict_need_maintenance_for_batch ():
     try:
         # Get the uploaded CSV file from the request
         file = request.files ['file']
+
+        if file.filename == "":
+            return jsonify({
+                "status": "error",
+                "message": "No file selected"
+            }), 400        
     
         # Read the file into a DataFrame
         input_df = pd.read_csv (file)