Take care of case where event has no date

amivapi/events/email_links.py

@@ -92,8 +92,10 @@ def on_delete_signup(token):
     event_name = data_event["title_en"]
     if event_name is None:
         event_name = data_event["title_en"]
-    print(data_event["time_start"])
-    event_date = datetime.strftime(data_event["time_start"], '%Y-%m-%d %H:%M')
+    if data_event["time_start"] is None:
+        event_date = datetime.strftime(data_event["time_start"], '%Y-%m-%d %H:%M')
+    else:
+        event_date = "a yet undefined day."
     # Serve the unregister_event page
     response = make_response(render_template("unregister_event.html",
                                              user=user,

amivapi/events/model.py

@@ -257,7 +257,6 @@
                 'description': 'Start time of the event itself. If you define '
                                'a start time, an end time is required, too.',
                 'example': '2018-10-17T18:00:00Z',
-
                 'type': 'datetime',
                 'nullable': True,
                 'default': None,
@@ -269,7 +268,6 @@
                 'description': 'End time of the event itself. If you define '
                                'an end time, a start time is required, too.',
                 'example': '2018-10-17T22:00:00Z',
-
                 'type': 'datetime',
                 'nullable': True,
                 'default': None,

amivapi/events/templates/unregister_event.html

@@ -29,7 +29,7 @@ <h1>
       </h1>
       <p>
         {% if user and event %}
-        We will irrevocably unregister you (<em>{{user}}</em>) from the event <em>{{event}}</em> on <em>{{event_date}}</em>.
+        We will irrevocably unregister you (<em>{{user}}</em>) from the event <em>{{event}}</em> on {{event_date}}.
         Is that ok?
         {% else %}
         You clicked on a opt-out link of the AMIV at ETHZ student organization. We cannot process your request,