Add public filters based on meta data (#3673)

* Add public filters based on meta data

* Fix licenseheaders

* ignore empty values

* Fix tests

* Full non-widget implementation

* Widget support

* Add a few tests

* Allow to reorder properties

* Fix isort

* Allow to opt-out for specific events

* Fix name clash between new and old field to make migration feasible

src/tests/api/test_events.py

@@ -198,6 +198,10 @@ def test_event_list_filter(token_client, organizer, event):
 
     resp = token_client.get('/api/v1/organizers/{}/events/?attr[type]='.format(organizer.slug))
     assert resp.status_code == 200
+    assert resp.data['count'] == 1
+
+    resp = token_client.get('/api/v1/organizers/{}/events/?attr[type]=Unknown'.format(organizer.slug))
+    assert resp.status_code == 200
     assert resp.data['count'] == 0
 
     resp = token_client.get('/api/v1/organizers/{}/events/?date_from_after=2017-12-27T10:00:00Z'.format(organizer.slug))
@@ -231,7 +235,10 @@ def test_event_get(token_client, organizer, event):
 
 @pytest.mark.django_db
 def test_event_create(team, token_client, organizer, event, meta_prop):
-    meta_prop.allowed_values = "Conference\nWorkshop"
+    meta_prop.choices = [
+        {"key": "Conference", "label": {"en": "Conference"}},
+        {"key": "Workshop", "label": {"en": "Workshop"}},
+    ]
     meta_prop.save()
     team.can_change_organizer_settings = False
     team.save()

src/tests/api/test_subevents.py

@@ -256,7 +256,7 @@ def test_all_subevents_list_filter(token_client, organizer, event, subevent):
 
 @pytest.mark.django_db
 def test_subevent_create(team, token_client, organizer, event, subevent, meta_prop, item):
-    meta_prop.allowed_values = "Conference\nWorkshop"
+    meta_prop.choices = [{"key": "Conference", "label": {"en": "Conference"}}, {"key": "Workshop", "label": {"en": "Workshop"}}]
     meta_prop.save()
     team.can_change_organizer_settings = False
     team.save()