Fix django polymorphic on django 1.9

cabot/rest_urls.py

@@ -36,17 +36,12 @@ def create_viewset(arg_model, arg_fields, arg_read_only_fields=(), no_create=Fal
     else:
         viewset_class = viewsets.ModelViewSet
 
-    arg_queryset = None
-    if issubclass(arg_model, PolymorphicModel):
-        arg_queryset = arg_model.objects.instance_of(arg_model)
-    else:
-        arg_queryset = arg_model.objects.all()
-
     class ViewSet(viewset_class):
-        queryset = arg_queryset
+        queryset = arg_model.objects
         serializer_class = Serializer
         ordering = ['id']
         filter_fields = arg_fields
+
     return ViewSet
 
 check_group_mixin_fields = (

cabot/settings.py

@@ -255,7 +255,7 @@ REST_FRAMEWORK = {
         'rest_framework.permissions.DjangoModelPermissions',
     ],
     'DEFAULT_FILTER_BACKENDS': [
-        'rest_framework.filters.DjangoFilterBackend',
+        'django_filters.rest_framework.DjangoFilterBackend',
         'rest_framework.filters.OrderingFilter',
     ]
 }

requirements.txt

@@ -7,12 +7,12 @@ django-appconf==1.0.2
 django-auth-ldap==1.2.6
 django-celery==3.1.17
 django-compressor==2.1.1
-django-filter==0.13
+django-filter==1.0.1
 django-jsonify==0.3.0
 django-mptt==0.6.0
 django-polymorphic==1.1
 Django>=1.9,<1.10
-djangorestframework>=3.4,<3.5
+djangorestframework>=3.5,<3.6
 freezegun==0.3.8
 gevent==1.0.1
 gunicorn==19.6.0