bugfix GeometryFilter for GIS and django-filter #814

drf_spectacular/contrib/django_filters.py

@@ -236,7 +236,24 @@ def _get_schema_from_model_field(self, auto_schema, filter_field, model):
         # potential side effects. Only after that fails, attempt to call
         # get_queryset() to check for potential query annotations.
         model_field = self._get_model_field(filter_field, model)
+
+        # this is a cross feature between rest-framework-gis and django-filter. Regular
+        # behavior needs to be sidestepped as the model information is lost down the line.
+        # TODO for now this will be just a string to cover WKT, WKB, and urlencoded GeoJSON
+        #   build_geo_schema(model_field) would yield the correct result
+        if self._is_gis(model_field):
+            return build_basic_type(OpenApiTypes.STR)
+
         if not isinstance(model_field, models.Field):
             qs = auto_schema.view.get_queryset()
             model_field = qs.query.annotations[filter_field.field_name].field
         return auto_schema._map_model_field(model_field, direction=None)
+
+    def _is_gis(self, field):
+        try:
+            from django.contrib.gis.db.models import GeometryField
+            from rest_framework_gis.filters import GeometryFilter
+
+            return isinstance(field, (GeometryField, GeometryFilter))
+        except ImportError:
+            return False

tests/contrib/test_rest_framework_gis.py

@@ -87,3 +87,40 @@ class PlainViewset(mixins.RetrieveModelMixin, mixins.ListModelMixin, viewsets.Ge
         generate_schema(None, patterns=router.urls),
         'tests/contrib/test_rest_framework_gis.yml'
     )
+
+
+@pytest.mark.contrib('rest_framework_gis', 'django_filter')
+@mock.patch('drf_spectacular.settings.spectacular_settings.ENUM_NAME_OVERRIDES', {})
+def test_geo_filter_set(no_warnings):
+    from django.contrib.gis.db.models import PointField
+    from django_filters import filters
+    from django_filters.rest_framework import DjangoFilterBackend
+    from rest_framework_gis.filters import GeometryFilter
+    from rest_framework_gis.filterset import GeoFilterSet
+
+    class GeoRegionModel(models.Model):
+        slug = models.CharField(max_length=32)
+        geom = PointField()
+
+    class RegionFilter(GeoFilterSet):
+        slug = filters.CharFilter(field_name='slug', lookup_expr='istartswith')
+        contains_geom = GeometryFilter(field_name='geom', lookup_expr='contains')
+
+        class Meta:
+            model = GeoRegionModel
+            fields = ['slug', 'contains_geom']
+
+    class XSerializer(serializers.Serializer):
+        slug = serializers.CharField()
+
+    class XViewset(mixins.ListModelMixin, viewsets.GenericViewSet):
+        serializer_class = XSerializer
+        queryset = GeoRegionModel.objects.none()
+        filterset_class = RegionFilter
+        filter_backends = [DjangoFilterBackend]
+
+    schema = generate_schema('/x', XViewset)
+    assert schema['paths']['/x/']['get']['parameters'] == [
+        {'in': 'query', 'name': 'contains_geom', 'schema': {'type': 'string'}},
+        {'in': 'query', 'name': 'slug', 'schema': {'type': 'string'}}
+    ]