From 894a94ce707489f42ddd494655af26c4e5fa6b24 Mon Sep 17 00:00:00 2001
From: OmegaDroid <dan@dwarvenhoard.com>
Date: Mon, 23 Oct 2017 15:21:56 +0100
Subject: [PATCH] replaced '.' for '__' in dotted ordering sources

---
 rest_framework/filters.py |  2 +-
 tests/test_filters.py     | 30 ++++++++++++++++++++++++++++++
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/rest_framework/filters.py b/rest_framework/filters.py
index 28b6995ec..d30135d2e 100644
--- a/rest_framework/filters.py
+++ b/rest_framework/filters.py
@@ -199,7 +199,7 @@ class OrderingFilter(BaseFilterBackend):
             raise ImproperlyConfigured(msg % self.__class__.__name__)
 
         return [
-            (field.source or field_name, field.label)
+            (field.source.replace('.', '__') or field_name, field.label)
             for field_name, field in serializer_class(context=context).fields.items()
             if not getattr(field, 'write_only', False) and not field.source == '*'
         ]
diff --git a/tests/test_filters.py b/tests/test_filters.py
index dc5b18068..bcfd7686a 100644
--- a/tests/test_filters.py
+++ b/tests/test_filters.py
@@ -320,6 +320,18 @@ class OrderingFilterSerializer(serializers.ModelSerializer):
         fields = '__all__'
 
 
+class OrderingDottedRelatedSerializer(serializers.ModelSerializer):
+    related_text = serializers.CharField(source='related_object.text')
+    related_title = serializers.CharField(source='related_object.title')
+
+    class Meta:
+        model = OrderingFilterRelatedModel
+        fields = (
+            'related_text',
+            'related_title',
+        )
+
+
 class DjangoFilterOrderingModel(models.Model):
     date = models.DateField()
     text = models.CharField(max_length=10)
@@ -484,6 +496,24 @@ class OrderingFilterTests(TestCase):
             {'id': 2, 'title': 'yxw', 'text': 'bcd'},
         ]
 
+    def test_ordering_by_dotted_source(self):
+        for obj in OrderingFilterModel.objects.all():
+            OrderingFilterRelatedModel.objects.create(related_object=obj)
+
+        class OrderingListView(generics.ListAPIView):
+            serializer_class = OrderingDottedRelatedSerializer
+            filter_backends = (filters.OrderingFilter,)
+            queryset = OrderingFilterRelatedModel.objects.all()
+
+        view = OrderingListView.as_view()
+        request = factory.get('/', {'ordering': 'related_object__text'})
+        response = view(request)
+        assert response.data == [
+            {'related_title': 'zyx', 'related_text': 'abc'},
+            {'related_title': 'yxw', 'related_text': 'bcd'},
+            {'related_title': 'xwv', 'related_text': 'cde'},
+        ]
+
     def test_ordering_with_nonstandard_ordering_param(self):
         with override_settings(REST_FRAMEWORK={'ORDERING_PARAM': 'order'}):
             reload_module(filters)