RelatedFilter.get_filter_subset => FilterSet.get_subset

Author: Ryan P Kilby

rest_framework_filters/filters.py

@@ -1,7 +1,6 @@
 from __future__ import absolute_import
 from __future__ import unicode_literals
 
-from collections import OrderedDict
 from django.utils import six
 
 from django_filters.filters import *
@@ -36,27 +35,6 @@ def fset(self, value):
         return locals()
     filterset = property(**filterset())
 
-    def get_filterset_subset(self, filter_names):
-        """
-        Returns a FilterSet subclass that contains the subset of filters
-        specified in `filter_names`. This is useful for creating FilterSets
-        used across relationships, as it minimizes the deepcopy overhead
-        incurred when instantiating the FilterSet.
-        """
-        BaseFilterSet = self.filterset
-
-        class FilterSetSubset(BaseFilterSet):
-            pass
-
-        FilterSetSubset.__name__ = str('%sSubset' % (BaseFilterSet.__name__))
-        FilterSetSubset.base_filters = OrderedDict([
-            (name, f)
-            for name, f in six.iteritems(BaseFilterSet.base_filters)
-            if name in filter_names
-        ])
-
-        return FilterSetSubset
-
     @property
     def field(self):
         # if no queryset is provided, default to the filterset's default queryset

rest_framework_filters/filterset.py

@@ -129,7 +129,7 @@ def get_filters(self):
 
             # otherwise build and insert it into the cache
             if subset_class is None:
-                subset_class = related_filter.get_filterset_subset(filter_names)
+                subset_class = related_filter.filterset.get_subset(filter_names)
                 self.cache_set(key, subset_class)
 
             # initialize and copy filters
@@ -162,6 +162,26 @@ def get_filter_name(cls, param):
         if isinstance(f, filters.RelatedFilter):
             return related_param
 
+    @classmethod
+    def get_subset(cls, filter_names):
+        """
+        Returns a FilterSet subclass that contains the subset of filters
+        specified in `filter_names`. This is useful for creating FilterSets
+        used across relationships, as it minimizes the deepcopy overhead
+        incurred when instantiating the FilterSet.
+        """
+        class FilterSetSubset(cls):
+            pass
+
+        FilterSetSubset.__name__ = str('%sSubset' % (cls.__name__))
+        FilterSetSubset.base_filters = OrderedDict([
+            (name, f)
+            for name, f in six.iteritems(cls.base_filters)
+            if name in filter_names
+        ])
+
+        return FilterSetSubset
+
     def cache_key(self, filterset, filter_names):
         return '%sSubset-%s' % (filterset.__name__, '-'.join(sorted(filter_names)), )
 

tests/test_filterset.py

@@ -304,9 +304,9 @@ def test_m2m_relation(self):
         titles = set([p.title for p in f])
         self.assertEqual(titles, set(["First post", "Second post"]))
 
-    def test_get_filterset_subset(self):
+    def test_get_subset(self):
         related_filter = NoteFilterWithRelated.base_filters['author']
-        filterset_class = related_filter.get_filterset_subset(['email'])
+        filterset_class = related_filter.filterset.get_subset(['email'])
 
         # ensure that the class name is useful when debugging
         self.assertEqual(filterset_class.__name__, 'UserFilterSubset')