Enhancement: support naming API fields differently than model fields

Author: TayHobbs

rest_framework_json_api/renderers.py

@@ -263,10 +263,13 @@ def extract_included(fields, resource, resource_instance, included_resources):
                     # For ManyRelatedFields if `related_name` is not set we need to access `foo_set` from `source`
                     relation_instance_or_manager = getattr(resource_instance, field.child_relation.source)
                 except AttributeError:
-                    if not hasattr(current_serializer, field.source):
+                    if hasattr(current_serializer, field.source):
+                        serializer_method = getattr(current_serializer, field.source)
+                        relation_instance_or_manager = serializer_method(resource_instance)
+                    elif hasattr(current_serializer.instance, field.source):
+                        relation_instance_or_manager = getattr(current_serializer.instance, field.source)
+                    else:
                         continue
-                    serializer_method = getattr(current_serializer, field.source)
-                    relation_instance_or_manager = serializer_method(resource_instance)
 
             new_included_resources = [key.replace('%s.' % field_name, '', 1)
                                       for key in included_resources