I also changed this
private $client = mystream:myport;
private $pass = 'mypassword';
and added my stream:myport on every bit where the localhost was mentioned on purge.php
Oof, it has been very long since I posted that here.
The link isn't even working anymore, so how did you even get the script?
Anyways: The $client variable is meant to be null as it's being replaced by the Guzzle Http Client a few lines later.
Opening in the browser might work as well, but this was actually meant to be a commandline script.
The script requires cURL to be available as a PHP extension in order to work. That should be enabled by default on most webhosts and in the default PHP binaries for Windows you can download from php.net
If it doesn't show anything at all, it's definitely broken.
Check your error_reporting:
Right below the comment in index.php add the following lines:
That should show you whatever error occured.