correct parsing input params

app.py

@@ -6,6 +6,7 @@ from io import BytesIO, StringIO
 from PIL import Image
 import pandas as pd
 import os.path
+import numpy as np
 
 DEBUG = True
 
@@ -35,6 +36,7 @@ def login(username, password) -> bool:
 
     if not len(df):
         return False
+    df = df.replace({np.nan: None})
 
     for idx, row in df.iterrows():
         if row['username'] == username and row['password'] == password:
@@ -42,7 +44,8 @@ def login(username, password) -> bool:
             restaurant_name = str(row['restaurant_name'])
             mode = 'waste'
             possible_modes = str(row.get('modes')).split(':')
-            possible_shifts = {i.split(':')[0]: i.split(':')[1] for i in str(row.get('shifts')).split('-')}
+            possible_shifts = {i.split(':')[0]: i.split(':')[1] for i in str(row.get('shifts')).split('-')} \
+                if row.get('shifts') else {'no shift': None}
 
             config_aux = {'restaurant_id': restaurant_id,
                           'restaurant_name': restaurant_name,