function RTMPPublishURL($domain, $hub, $streamKey, $expireAfterSeconds, $accessKey, $secretKey)
{
    $expire = time() + $expireAfterSeconds;
    $path = sprintf("/%s/%s?e=%d", $hub, $streamKey, $expire);
    $token = $accessKey . ":" . Utils::sign($secretKey, $path);
    return sprintf("rtmp://%s%s&token=%s", $domain, $path, $token);
}