Avoid a stale read listing generic memberships

arkindex/users/api.py

@@ -668,7 +668,8 @@ class GenericMembershipsList(ACLMixin, ListAPIView):
         except (AttributeError, ValueError):
             raise ValidationError({key: [f"'{content_id}' is not a valid UUID."]})
 
-        return get_object_or_404(self.content_object_params[key], id=content_uuid)
+        # Use default database in case the content object has just been created
+        return get_object_or_404(self.content_object_params[key].objects.using('default'), id=content_uuid)
 
     def get_queryset(self):
         content_object = self.get_content_object()
@@ -680,7 +681,9 @@ class GenericMembershipsList(ACLMixin, ListAPIView):
         if not self.has_access(content_object, Role.Guest.value, **access_params):
             raise PermissionDenied(detail='You do not have the required access level to list members for this content.')
 
+        # Avoid a stale read when adding/deletig a member
         qs = content_object.memberships \
+            .using('default') \
             .prefetch_related(
                 'user',
                 Prefetch('group', queryset=Group.objects.annotate(members_count=Count('memberships')))