Thank you very much for your help Dobbel.
You can make this work (web & mobile app ) 99,99% guaranteed with https://expressjs.com/ using a rest API.
The Rest API, for talking with the frontend, I understand.
If you need to go the socket way + docker , I could help but that’s a bit more complicated. I have used sockets & docker for all my apps ( mobile/pwa/spa).
No. The socket was only implemented to be able to show in the frontend realtime info, without having to poll. While charging, things like charge level, voltage or power.
With realtime voltage one can make an idea of the load it is on the grid supply. For one’s like me that have a shitty supply.
And power, to be sure I’m not exceeding the contracted amount.
I’ve read that some frameworks for NodeJs already integrate socketio for the frontend to backend integration. I should take a look in how they determine the endpoint address.