def handler(self, event, context): """ Request handler method for fetch resource function. """ if event is None or Constants.event_path_parameters() not in event: return response(http.HTTPStatus.BAD_REQUEST, Constants.error_insufficient_parameters()) if Constants.event_path_parameter_identifier() not in event[ Constants.event_path_parameters()]: return response(http.HTTPStatus.BAD_REQUEST, Constants.error_insufficient_parameters()) _identifier = event[Constants.event_path_parameters()][ Constants.event_path_parameter_identifier()] _http_method = event[Constants.event_http_method()] if _http_method == HttpConstants.http_method_get() and _identifier: _ddb_response = self.__retrieve_resource(_identifier) if len(_ddb_response[ Constants.ddb_response_attribute_name_items()]) == 0: return response(http.HTTPStatus.NOT_FOUND, json.dumps(_ddb_response)) return response(http.HTTPStatus.OK, json.dumps(_ddb_response)) return response(http.HTTPStatus.BAD_REQUEST, Constants.error_insufficient_parameters())