tags fix mtm

apps/tag/serializers.py

@@ -2,11 +2,9 @@
 from rest_framework import serializers
 from rest_framework.fields import SerializerMethodField
 
-from establishment.models import (Establishment, EstablishmentType,
-                                  EstablishmentSubType)
+from establishment.models import (Establishment, EstablishmentType)
 from news.models import News, NewsType
 from tag import models
-from tag.models import Tag
 from utils.exceptions import (ObjectAlreadyAdded, BindingObjectNotFound,
                               RemovedBindingObjectNotFound)
 from utils.serializers import TranslatedField
@@ -79,18 +77,21 @@ class TagCategoryBaseSerializer(serializers.ModelSerializer):
 
     def get_tags(self, obj):
         query_params = dict(self.context['request'].query_params)
+
         if len(query_params) > 1:
-            return None
-
-        tags = Tag.objects.all()
+            return []
 
+        params = {}
         if 'establishment_type' in query_params:
-            types = query_params['establishment_type']
-            tags = tags.filter(establishments__establishment_type__index_name__in=types).distinct()
+            params = {
+                'establishments__isnull': False,
+            }
         elif 'product_type' in query_params:
-            types = query_params['product_type']
-            tags = tags.filter(products__product_type__index_name__in=types).distinct()
+            params = {
+                'products__isnull': False,
+            }
 
+        tags = obj.tags.filter(**params).distinct()
         return TagBaseSerializer(instance=tags, many=True, read_only=True).data