Help with Authentication

[A-O]

Can someone point me in the right direction for authenticating users via the shared-secret mode?

I have all the configs setup and working correctly on my Spreed server, now I am not sure how to register a user from my webapp (on a different server), specifically register and create a room.

I see there is a rest api but I can't see how to send user/session info when attempting to join a room?

Ultimately I would like to restrict my Spreed server usage (ability to create rooms) to only users of my webapp just not sure how to connect the dots..., I have root access to both servers. Sorry if this is a noob question, thanks in advance!

My assumed line of communication:

1. User logs into my WebApp
2. WebApp has knowledge of shared secret
3. WebApp uses shared secret to create username:key combo
   ?
   ?
   ?
4. User loads spreed server URL into browser and is logged in with ability to create rooms.