Fix event speaker lists in schedule api

src/api/schedule.py

@@ -148,17 +148,16 @@ class ScheduleEncoder(json.JSONEncoder):
     def collect_persons(self, event):
         persons = []
 
-        # TODO remove this workaround once imported speakers are stored as participants
-        #      and have links and biography=description
-        if event.additional_data and 'persons' in event.additional_data and len(event.additional_data['persons']) > 0:
-            persons = event.additional_data['persons']
-        else:
         if hasattr(event, 'speakers'):
             # event is a QuerySet and already fetched speakers
-                persons = list(event.speakers)
+            persons = [speaker.participant for speaker in event.speakers]
         else:
             # direct event lookup -> fetch persons via public_speakers
-                persons = list(event.public_speakers)
+            persons = event.public_speakers
+
+        # TODO remove this workaround once imported speakers are stored as participants
+        if event.additional_data and 'persons' in event.additional_data and len(event.additional_data['persons']) > 0:
+            persons += event.additional_data['persons']
 
         return [self.encode_person(person) for person in persons]
 

src/core/models/events.py

@@ -223,11 +223,12 @@ class Event(TaggedItemMixin, BackendMixin, models.Model):
         return hub_absolute('plainui:event', event_slug=self.slug, i18n=False)
 
     @property
-    def public_speakers(self):
+    def public_speakers(self) -> list:
         """Returns a list of all public speakers of this event."""
-        persons = self.participants.filter(is_public=True, role=EventParticipant.Role.SPEAKER).select_related('participant')
+        persons = self.participants.filter(is_public=True, role=EventParticipant.Role.SPEAKER).values_list('participant', flat=True)
 
-        if self.kind == Event.Kind.SELF_ORGANIZED and self.owner:
+        # If there is no speaker for an SoS, the owner is automatically added.
+        if self.kind == Event.Kind.SELF_ORGANIZED and not persons and self.owner:
             persons.add(self.owner)
 
         return persons