This is a simplest realization of long-polling server.
All data is stored in RAM, so it will be lost after server restart.
There is no request logging or error handling features implemented, but you can find it in advanced app file located somewhere in this repo 😅
POST
example.com/any_string?data=any_data => 200 OKGET
example.com/any_string?last_id=0&timeout=60 => 200 OK {"any_data"}