eduVPN / vpn-server-api

    const USER_ID_PATTERN = '/^[a-zA-Z0-9-_.@]+$/';

    const DATE_PATTERN = '/^[0-9]{4}-[0-9]{2}-[0-9]{2}$/';

    public static function commonName($commonName, $isRequired)

    {

        $commonName = !empty($commonName) ? $commonName : null;

        if (!$isRequired && is_null($commonName)) {

            return;

        }

        if (0 === preg_match(self::COMMON_NAME_PATTERN, $commonName)) {

            throw new BadRequestException('invalid value for "common_name"');

        }

        if ('..' === $commonName) {

            throw new BadRequestException('"common_name" cannot be ".."');

        }

        return $commonName;

    }

    public static function userId($userId, $isRequired)

    {

        return $commonName;

    }

    public static function userId($userId, $isRequired)

    {

        $userId = !empty($userId) ? $userId : null;

        if (!$isRequired && is_null($userId)) {

            return;

        }

        if (0 === preg_match(self::USER_ID_PATTERN, $userId)) {

            throw new BadRequestException('invalid value for "user_id"');

        }

        if ('..' === $userId) {

            throw new BadRequestException('"user_id" cannot be ".."');

        }

        return $userId;

    }

    public static function date($date, $isRequired)

    {