Hello @it33,
sorry, my linux shell experience is a little bit clumsy. Sometimes i find my solution by trial and errror, sometimes not. I hoped, this problem would have been solved by someone else yet.
My approach was using curl to fetch rss feeds and to send them to my (yet working) webhook. I started at http://www.askdavetaylor.com/can_i_track_an_rss_feed_with_a_shell_script/, got stuck and stumbled upon rsstail, which could lead to a solution, but I have no idea how to solve this.
Bye,
Markus