How to get .txt TLEs from website using webhooks?

Loving my Electron but I am very very very new to the web type api stuff, I’ve managed to get some JSON info back thanks to some of the awesome tutorials here using response templates but I’m currently trying to obtain the ISS TLE from http://www.celestrak.com/NORAD/elements/stations.txt and could use some help. Just trying to grab the ISS specific lines, once per day. I might be going about this the complete wrong way, just looking for a little guidance. Any help is appreciated. I found one website that returned TLEs in JSON but they were not up to date enough for my purposes. Thanks