I don't mean custom authentication with firebase. What I need is slightly different from that custom authentication that generates tokens in application server and allows access in firebase. Actually, I'm trying to authenticate in firebase with e-mail and password , for instance, and with that authentication be able to access restful services in some application server. Is this possible ? I think that in some way an token could be sent to application server after firebase authentication and that server would validate the auth token against firebase.
Client --------authenticates ------->> Firebase
Client <<--------auth token ---------- Firebase
Client --------- sends ------------->> Application server (NodeJS)
App Server ------- validates (auth token) ---->> Firebase
Thanks in advance.