protected function add_additional_fields_to_object($object, $request) { $additional_fields = $this->get_additional_fields(); foreach ($additional_fields as $field_name => $field_options) { if (!$field_options['get_callback']) { continue; } $object[$field_name] = call_user_func($field_options['get_callback'], $object, $field_name, $request, $this->get_object_type()); } return $object; }