This PHP library implements a subscriber for PubSubHubbub.
It was written by Josh Fraser and is released under the Apache 2.0 License
Modified by Andrei Telteu to work with the latest modifications by Youtube's pubsubhubbub service to allow challenge verification.
Install this fork using this command:
composer require onlinedigital/pubsubhubbub-php-subscriberuse \Pubsubhubbub\Subscriber\Subscriber;
$hub_url = "http:https://pubsubhubbub.appspot.com";
$callback_url = "put your own endpoint here";
// create a new subscriber
$s = new Subscriber($hub_url, $callback_url);
$feed = "http:https://feeds.feedburner.com/onlineaspect";
// subscribe to a feed
$s->subscribe($feed);
// unsubscribe from a feed
$s->unsubscribe($feed);