This is a PHP class that can read RSS feeds.
You can either clone the repository or you can use composer to install UpdateSite.
If you do not have composer you can get it at https://getcomposer.org/download/. Just follow the instruction to install it globally.
Once you have composer select a directory where you want your repository and enter:
composer require bartonlp/rssfeed:dev-master
There is an example file (test.php) in the 'docs' directory along with a XML and image file that you can run.