How to proactively notify the browser through ubus?

I want to notify the browser through ubus (such as the insertion and removal of a U disk). The current solution is to use nginx as a websocket server to establish a websocket connection with the browser, and nginx integrates the ubus module (see https://github.com/Ansuel /nginx-ubus-module), here I need to develop a websocket module nginx as a websocket server. I don't know if there are any other better solutions?

There was some attempt to create a notification framework in Luci:

You can pull messages via UBUS periodically and that should be fine to see an event with some delay