Checking eSIM promo codes with ESP32

[Daur29]

Hey,

I’m working on a small project where my ESP32 automatically checks if an eSIM promo code is still valid and sends me a notification. The problem is the site uses redirects and JavaScript, so it’s not easy to parse the info. Any ideas on libraries or methods to fetch this kind of web data on ESP32 without running a full browser?

[Daur29]

Alright, quick update after thinking it through a bit. I was trying to make everything run directly on the ESP32. In theory it sounded neat. In practice… not really. With the redirects and JS on that site, the ESP32 can fetch the page but it struggles once you actually need to interpret what’s going on. So I changed the approach slightly. I’ve put a small script on a server that handles the messy part (following redirects, checking the page, that sort of thing). The ESP32 just calls it from time to time and gets back a simple status. Way cleaner overall. Not as fully embedded as I first wanted, but honestly it saves a lot of headaches. Right now I’m testing it with an esim voucher I’m keeping an eye on, just to see if the system correctly flags it once it becomes invalid. So far it seems to behave alright.