I found an interesting UPS board with a 10.000mAh LiPo battery on Amazon to provide backup power to my Pi running HA in Greece (frequent power outages). I have added a link to the documentation below.
For the board to gracefully shutdown the Pi, it is wired to the UART pins on the GPIO headers. The software is a .py script that needs to be added to /etc/rc.local on the host os. It imports RPi.GPIO to connect to the pin signaling system_halt on battery low. Is python3 and RPi.GPIO available on HA OS?
I am running HA OS and would like to continue doing so because of the auto-updates of all components. I know that I can ssh as root into the host (after jumping through a few hoops with authorized_keys) and I would be willing to do that if there is no better alternative (existing integration)?
Has anyone done this or similar? Will it work if the host shutdowns? will the containers (core and supervisor) be gracefully stopped as well?