added prefetch select related

apps/establishment/models.py

@@ -16,6 +16,7 @@ from phonenumber_field.modelfields import PhoneNumberField
 from collection.models import Collection
 from location.models import Address
 from main.models import Award
+from tag.models import Tag, TagCategory
 from review.models import Review
 from utils.models import (ProjectBaseMixin, TJSONField, URLImageMixin,
                           TranslatedFieldsMixin, BaseAttributes)
@@ -24,6 +25,18 @@ from utils.models import (ProjectBaseMixin, TJSONField, URLImageMixin,
 class EstablishmentTypeQuerySet(models.QuerySet):
     """QuerySet for model EstablishmentType."""
 
+    def with_base_related(self):
+        """Return QuerySet with base related."""
+        return self.prefetch_related(
+            models.Prefetch('tag_categories',
+                            EstablishmentTypeTagCategory.objects.select_related('tag_category')),
+            models.Prefetch('establishmentsubtype_set',
+                            EstablishmentSubType.objects.prefetch_related(
+                                models.Prefetch(
+                                    'tag_categories',
+                                    EstablishmentSubTypeTagCategory.objects.select_related('tag_category'))))
+        )
+
 
 # todo: establishment type&subtypes check
 class EstablishmentType(TranslatedFieldsMixin, ProjectBaseMixin):
@@ -35,6 +48,8 @@ class EstablishmentType(TranslatedFieldsMixin, ProjectBaseMixin):
                       help_text='{"en-GB":"some text"}')
     use_subtypes = models.BooleanField(_('Use subtypes'), default=True)
 
+    objects = EstablishmentTypeQuerySet.as_manager()
+
     class Meta:
         """Meta class."""
 

apps/establishment/views/back.py

@@ -167,7 +167,7 @@ class EstablishmentTypeRUDView(generics.RetrieveUpdateDestroyAPIView):
 class EstablishmentTypeTagListView(generics.ListAPIView):
     """List of tags with categories by establishment type."""
     serializer_class = serializers.EstablishmentTagsByType
-    queryset = models.EstablishmentType.objects.all()
+    queryset = models.EstablishmentType.objects.with_base_related()
     filter_class = EstablishmentTypeTagFilter
     permission_classes = (permissions.AllowAny, )
     pagination_class = None