MySQL resignal and customised error message

gistfile1.txt

DECLARE EXIT HANDLER FOR SQLEXCEPTION
BEGIN
    DECLARE v_error_message VARCHAR(512);
    DECLARE v_condition_number INT(1) UNSIGNED;

    ROLLBACK;
    GET DIAGNOSTICS v_condition_number = NUMBER;
    GET DIAGNOSTICS CONDITION v_condition_number v_error_message = MESSAGE_TEXT;
    SET v_error_message = CONCAT('Rolledback due to: "', v_error_message, '"');
    RESIGNAL SET MESSAGE_TEXT = v_error_message;
END;