public static function generateSalt(
        $chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789',
        $saltLength = 30
    ){
        return substr(str_shuffle(str_repeat((string) $chars,10)),0, (int) $saltLength);
    }