FASTAPI Websocket Authentication

I need to build realtime application
Client 1 emit Smartband data heartrate as athlete
FASTAPI Server as receiver of Client 1 and sender to Client 2
Client 2 receive heart rate data as coach
I need validate authentication token
1 athlete for 1 coach
1 coach for some athlete
They must be in some room
I don’t understand usage of Websocket in FASTAPI, but I understand concept room of Socketio. Unfortunately, FastAPI doesn’t fully support Socketio.

How do I achieve my goals to build realtime application that have auth process using FastAPI Websocket?