fix django-filter related resolution. improve test #150 #151

drf_spectacular/contrib/django_filters.py

@@ -1,4 +1,4 @@
-from drf_spectacular.plumbing import build_parameter_type, get_view_model
+from drf_spectacular.plumbing import build_parameter_type, follow_field_source, get_view_model
 from drf_spectacular.utils import OpenApiParameter
 
 try:
@@ -20,7 +20,8 @@ def get_schema_operation_parameters(self, view):
 
         parameters = []
         for field_name, field in filterset_class.base_filters.items():
-            model_field = model._meta.get_field(field.field_name)
+            path = field.field_name.split('__')
+            model_field = follow_field_source(model, path)
 
             parameters.append(build_parameter_type(
                 name=field_name,

tests/contrib/test_django_filters.py

@@ -23,19 +23,25 @@ class Product(models.Model):
     price = models.FloatField()
 
 
+class SubProduct(models.Model):
+    sub_price = models.FloatField()
+    product = models.ForeignKey(Product, on_delete=models.CASCADE)
+
+
 class ProductSerializer(serializers.ModelSerializer):
     class Meta:
         model = Product
         fields = '__all__'
 
 
 class ProductFilter(FilterSet):
-    min_price = NumberFilter(field_name="price", lookup_expr='gte')
     max_price = NumberFilter(field_name="price", lookup_expr='lte')
+    max_sub_price = NumberFilter(field_name="subproduct__sub_price", lookup_expr='lte')
+    sub = NumberFilter(field_name="subproduct", lookup_expr='exact')
 
     class Meta:
         model = Product
-        fields = ['category', 'in_stock', 'min_price', 'max_price']
+        fields = ['category', 'in_stock', 'max_price']
 
 
 class ProductViewset(viewsets.ReadOnlyModelViewSet):
@@ -63,11 +69,24 @@ def test_django_filters(no_warnings):
 @pytest.mark.urls(__name__)
 @pytest.mark.django_db
 def test_django_filters_requests(no_warnings):
-    Product.objects.create(category='X', price=4, in_stock=True)
+    product = Product.objects.create(category='X', price=4, in_stock=True)
+    SubProduct.objects.create(sub_price=5, product=product)
 
-    response = APIClient().get('/api/products/?min_price=3')
+    response = APIClient().get('/api/products/?max_price=1')
+    assert response.status_code == 200
+    assert len(response.json()) == 0
+    response = APIClient().get('/api/products/?max_price=5')
+    assert response.status_code == 200
+    assert len(response.json()) == 1
+    response = APIClient().get('/api/products/?max_sub_price=1')
+    assert response.status_code == 200
+    assert len(response.json()) == 0
+    response = APIClient().get('/api/products/?max_sub_price=6')
+    assert response.status_code == 200
+    assert len(response.json()) == 1
+    response = APIClient().get('/api/products/?sub=1')
     assert response.status_code == 200
     assert len(response.json()) == 1
-    response = APIClient().get('/api/products/?min_price=5')
+    response = APIClient().get('/api/products/?sub=2')
     assert response.status_code == 200
     assert len(response.json()) == 0

tests/contrib/test_django_filters.yml

@@ -28,11 +28,16 @@ paths:
           format: float
         description: max_price
       - in: query
-        name: min_price
+        name: max_sub_price
         schema:
           type: number
           format: float
-        description: min_price
+        description: max_sub_price
+      - in: query
+        name: sub
+        schema:
+          type: integer
+        description: sub
       tags:
       - products
       security: