Avoided shadowing of exception when rendering errors (#1220)

Author: sliverc

CHANGELOG.md

@@ -22,6 +22,7 @@ any parts of the framework not mentioned in the documentation should generally b
 * `ModelSerializer` fields are now returned in the same order than DRF
 * Avoided that an empty attributes dict is rendered in case serializer does not
   provide any attribute fields.
+* Avoided shadowing of exception when rendering errors (regression since 4.3.0).
 
 ### Removed
 

rest_framework_json_api/utils.py

@@ -381,18 +381,19 @@ def format_drf_errors(response, context, exc):
             errors.extend(format_error_object(message, "/data", response))
     # handle all errors thrown from serializers
     else:
-        # Avoid circular deps
-        from rest_framework import generics
-
-        has_serializer = isinstance(context["view"], generics.GenericAPIView)
-        if has_serializer:
+        try:
             serializer = context["view"].get_serializer()
             fields = get_serializer_fields(serializer) or dict()
             relationship_fields = [
                 format_field_name(name)
                 for name, field in fields.items()
                 if is_relationship_field(field)
             ]
+        except Exception:
+            # ignore potential errors when retrieving serializer
+            # as it might shadow error which is currently being
+            # formatted
+            serializer = None
 
         for field, error in response.data.items():
             non_field_error = field == api_settings.NON_FIELD_ERRORS_KEY
@@ -401,7 +402,7 @@ def format_drf_errors(response, context, exc):
             if non_field_error:
                 # Serializer error does not refer to a specific field.
                 pointer = "/data"
-            elif has_serializer:
+            elif serializer:
                 # pointer can be determined only if there's a serializer.
                 rel = "relationships" if field in relationship_fields else "attributes"
                 pointer = f"/data/{rel}/{field}"

tests/test_views.py

@@ -154,6 +154,17 @@ def test_list_with_include_nested_related_field(
             "included"
         ]
 
+    @pytest.mark.urls(__name__)
+    def test_list_with_invalid_include(self, client, foreign_key_source):
+        url = reverse("foreign-key-source-list")
+        response = client.get(url, data={"include": "invalid"})
+        assert response.status_code == status.HTTP_400_BAD_REQUEST
+        result = response.json()
+        assert (
+            result["errors"][0]["detail"]
+            == "This endpoint does not support the include parameter for path invalid"
+        )
+
     @pytest.mark.urls(__name__)
     def test_list_with_default_included_resources(self, client, foreign_key_source):
         url = reverse("default-included-resources-list")