public function withUserInfo($user, $password = null)
    {
        $username = rawurlencode($user);

        if (strlen($username) > 0) {
            return $this->with('userInfo', $this->constructString([
                '%s%s'  => $username,
                '%s:%s' => rawurlencode($password),
            ]));
        }

        return $this->with('userInfo', '');
    }