better subtitles for location groups and more caching in query set

src/c3nav/mapdata/api.py

@@ -262,13 +262,34 @@ class LocationViewSet(RetrieveModelMixin, GenericViewSet):
                 AccessPermission.cache_key_for_request(self.request)
             )
             queryset = cache.get(queryset_cache_key, None)
-            if queryset is None:
+            if queryset is None or 1:
                 queryset = self.get_queryset(mode=('searchable' if searchable else 'searchable-describe'))
-                cache.set(queryset_cache_key, queryset, 300)
 
-            queryset = (obj.get_child() for obj in queryset)
-            if searchable:
-                queryset = sorted(queryset, key=operator.attrgetter('order'), reverse=True)
+                queryset = tuple(obj.get_child() for obj in queryset)
+
+                if searchable:
+                    queryset = sorted(queryset, key=operator.attrgetter('order'), reverse=True)
+                else:
+                    queryset = tuple(queryset)
+
+                # add locations to groups
+                locationgroups = {obj.pk: obj for obj in queryset if isinstance(obj, LocationGroup)}
+                for group in locationgroups.values():
+                    group.locations = []
+                for obj in queryset:
+                    if not isinstance(obj, SpecificLocation):
+                        continue
+                    for group in obj.groups.all():
+                        group = locationgroups.get(group.pk, None)
+                        if group is not None:
+                            group.locations.append(obj)
+
+                # precache cached properties
+                for obj in queryset:
+                    # noinspection PyStatementEffect
+                    obj.subtitle, obj.order
+
+                cache.set(queryset_cache_key, queryset, 300)
 
             result = tuple(obj.serialize(include_type=True, detailed=detailed, geometry=geometry) for obj in queryset)
             cache.set(cache_key, result, 300)

src/c3nav/mapdata/models/locations.py

@@ -5,7 +5,9 @@ from django.apps import apps
 from django.db import models
 from django.db.models import Prefetch
 from django.utils.functional import cached_property
+from django.utils.text import format_lazy
 from django.utils.translation import ugettext_lazy as _
+from django.utils.translation import ungettext_lazy
 
 from c3nav.mapdata.models.access import AccessRestrictionMixin
 from c3nav.mapdata.models.base import SerializableMixin, TitledMixin
@@ -87,7 +89,7 @@ class Location(LocationSlug, AccessRestrictionMixin, TitledMixin, models.Model):
 
     def _serialize(self, **kwargs):
         result = super()._serialize(**kwargs)
-        result['subtitle'] = self.subtitle
+        result['subtitle'] = str(self.subtitle)
         result['can_search'] = self.can_search
         result['can_describe'] = self.can_search
         return result
@@ -275,7 +277,13 @@ class LocationGroup(Location, models.Model):
 
     @property
     def subtitle(self):
-        return self.category.title
+        result = self.category.title
+        if hasattr(self, 'locations'):
+            return format_lazy(_('{category_title}, {num_locations}'),
+                               category_title=result,
+                               num_locations=(ungettext_lazy('%(num)d location', '%(num)d locations', 'num') %
+                                              {'num': len(self.locations)}))
+        return result
 
     @cached_property
     def order(self):