From 0425985dab3e468c5e9e2edde4e747888e554f50 Mon Sep 17 00:00:00 2001
From: Kike Isidoro <heisba@gmail.com>
Date: Fri, 2 Aug 2019 16:31:28 +0200
Subject: [PATCH] Check for filters defined on base filterset classes

---
 graphene_django/filter/tests/test_fields.py | 83 +++++++++++++++++++++
 graphene_django/filter/utils.py             | 22 +++---
 2 files changed, 96 insertions(+), 9 deletions(-)

diff --git a/graphene_django/filter/tests/test_fields.py b/graphene_django/filter/tests/test_fields.py
index 99876b6..026f909 100644
--- a/graphene_django/filter/tests/test_fields.py
+++ b/graphene_django/filter/tests/test_fields.py
@@ -818,3 +818,86 @@ def test_integer_field_filter_type():
         }
     """
     )
+
+
+def test_filter_filterset_based_on_mixin():
+    class ArticleFilterMixin:
+
+        @classmethod
+        def get_filters(cls):
+            filters = super().get_filters()
+            filters.update({
+                'viewer__email__in': django_filters.CharFilter(
+                    method='filter_email_in',
+                    field_name='reporter__email__in',
+                ),
+            })
+
+            return filters
+
+    class NewArticleFilter(ArticleFilterMixin, ArticleFilter):
+        pass
+
+    class NewReporterNode(DjangoObjectType):
+        class Meta:
+            model = Reporter
+            interfaces = (Node,)
+
+    class NewArticleFilterNode(DjangoObjectType):
+        viewer = Field(NewReporterNode)
+
+        class Meta:
+            model = Article
+            interfaces = (Node,)
+            filterset_class = NewArticleFilter
+
+        def resolve_viewer(self, info):
+            return self.reporter
+
+    class Query(ObjectType):
+        all_articles = DjangoFilterConnectionField(NewArticleFilterNode)
+
+    reporter = Reporter.objects.create(
+        first_name="John", last_name="Doe", email="john@doe.com")
+
+    article = Article.objects.create(
+        headline="Hello",
+        reporter=reporter,
+        editor=reporter,
+        pub_date=datetime.now(),
+        pub_date_time=datetime.now())
+
+    schema = Schema(query=Query)
+
+    query = """
+        query NodeFilteringQuery {
+            allArticles {
+                edges {
+                    node {
+                        viewer {
+                            email
+                        }
+                    }
+                }
+            }
+        }
+    """
+
+    expected = {
+        "allArticles": {
+            "edges": [
+                {
+                    "node": {
+                        "viewer": {
+                            "email": reporter.email,
+                        }
+                    }
+                }
+            ]
+        }
+    }
+
+    result = schema.execute(query)
+
+    assert not result.errors
+    assert result.data == expected
diff --git a/graphene_django/filter/utils.py b/graphene_django/filter/utils.py
index 00030a0..81efb63 100644
--- a/graphene_django/filter/utils.py
+++ b/graphene_django/filter/utils.py
@@ -13,21 +13,25 @@ def get_filtering_args_from_filterset(filterset_class, type):
     args = {}
     model = filterset_class._meta.model
     for name, filter_field in six.iteritems(filterset_class.base_filters):
+        form_field = None
+
         if name in filterset_class.declared_filters:
             form_field = filter_field.field
         else:
             field_name = name.split("__", 1)[0]
-            model_field = model._meta.get_field(field_name)
 
-            if hasattr(model_field, "formfield"):
-                form_field = model_field.formfield(
-                    required=filter_field.extra.get("required", False)
-                )
+            if hasattr(model, field_name):
+                model_field = model._meta.get_field(field_name)
 
-            # Fallback to field defined on filter if we can't get it from the
-            # model field
-            if not form_field:
-                form_field = filter_field.field
+                if hasattr(model_field, "formfield"):
+                    form_field = model_field.formfield(
+                        required=filter_field.extra.get("required", False)
+                    )
+
+        # Fallback to field defined on filter if we can't get it from the
+        # model field
+        if not form_field:
+            form_field = filter_field.field
 
         field_type = convert_form_field(form_field).Argument()
         field_type.description = filter_field.label