From 4bdcf054ebdb29e84ea190bb6becc8dc27ca286d Mon Sep 17 00:00:00 2001
From: Bas Stottelaar <basstottelaar@gmail.com>
Date: Fri, 28 Jul 2017 16:46:39 +0200
Subject: [PATCH] Pass context object to FilterSet instance to support
 request-baed filtering (fixes #203).

---
 docs/filtering.rst                          | 20 ++++++++++
 graphene_django/filter/fields.py            |  3 +-
 graphene_django/filter/tests/test_fields.py | 42 +++++++++++++++++++++
 3 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/docs/filtering.rst b/docs/filtering.rst
index f6ad882..2e6b87f 100644
--- a/docs/filtering.rst
+++ b/docs/filtering.rst
@@ -126,3 +126,23 @@ create your own ``Filterset`` as follows:
         # We specify our custom AnimalFilter using the filterset_class param
         all_animals = DjangoFilterConnectionField(AnimalNode,
                                                   filterset_class=AnimalFilter)
+
+The context argument is passed on as the `request argument <http://django-filter.readthedocs.io/en/latest/guide/usage.html#request-based-filtering>`__
+in a ``django_filters.FilterSet`` instance. You can use this to customize your
+filters to be context-dependent. We could modify the ``AnimalFilter`` above to
+pre-filter animals owned by the authenticated user (set in ``context.user``).
+
+.. code:: python
+
+    class AnimalFilter(django_filters.FilterSet):
+        # Do case-insensitive lookups on 'name'
+        name = django_filters.CharFilter(lookup_type='iexact')
+
+        class Meta:
+            model = Animal
+            fields = ['name', 'genus', 'is_domesticated']
+
+        @property
+        def qs(self):
+            # The query context can be found in self.request.
+            return super(AnimalFilter, self).filter(owner=self.request.user)
diff --git a/graphene_django/filter/fields.py b/graphene_django/filter/fields.py
index fc414bf..68a9072 100644
--- a/graphene_django/filter/fields.py
+++ b/graphene_django/filter/fields.py
@@ -73,7 +73,8 @@ class DjangoFilterConnectionField(DjangoConnectionField):
         filter_kwargs = {k: v for k, v in args.items() if k in filtering_args}
         qs = filterset_class(
             data=filter_kwargs,
-            queryset=default_manager.get_queryset()
+            queryset=default_manager.get_queryset(),
+            request=context
         ).qs
 
         return super(DjangoFilterConnectionField, cls).connection_resolver(
diff --git a/graphene_django/filter/tests/test_fields.py b/graphene_django/filter/tests/test_fields.py
index 1b24ff2..565e4f2 100644
--- a/graphene_django/filter/tests/test_fields.py
+++ b/graphene_django/filter/tests/test_fields.py
@@ -136,6 +136,48 @@ def test_filter_shortcut_filterset_extra_meta():
     assert 'headline' not in field.filterset_class.get_fields()
 
 
+def test_filter_shortcut_filterset_context():
+    class ArticleContextFilter(django_filters.FilterSet):
+
+        class Meta:
+            model = Article
+            exclude = set()
+
+        @property
+        def qs(self):
+            qs = super(ArticleContextFilter, self).qs
+            return qs.filter(reporter=self.request.reporter)
+
+    class Query(ObjectType):
+        context_articles = DjangoFilterConnectionField(ArticleNode, filterset_class=ArticleContextFilter)
+
+    r1 = Reporter.objects.create(first_name='r1', last_name='r1', email='r1@test.com')
+    r2 = Reporter.objects.create(first_name='r2', last_name='r2', email='r2@test.com')
+    Article.objects.create(headline='a1', pub_date=datetime.now(), reporter=r1, editor=r1)
+    Article.objects.create(headline='a2', pub_date=datetime.now(), reporter=r2, editor=r2)
+
+    class context(object):
+        reporter = r2
+
+    query = '''
+    query {
+        contextArticles {
+            edges {
+                node {
+                    headline
+                }
+            }
+        }
+    }
+    '''
+    schema = Schema(query=Query)
+    result = schema.execute(query, context_value=context())
+    assert not result.errors
+
+    assert len(result.data['contextArticles']['edges']) == 1
+    assert result.data['contextArticles']['edges'][0]['node']['headline'] == 'a2'
+
+
 def test_filter_filterset_information_on_meta():
     class ReporterFilterNode(DjangoObjectType):