dotEngine php sdk
$appsecret = '';
$appkey = '';
$dotEngine = new DotEngine($appkey, $appsecret);
$dotEngine->setConnectTimeout(20);
$token = $dotEngine->createToken('room', 'user', 36000*24);
https://github.com/firebase/php-jwt/blob/master/src/JWT.php
many thanks to @SN511 provide the php version sdk