[keycloak-user] custom federation/authentication

[Simon Gordon]

Hello

Looking for some guidance please - let's say that we want to authenticate 
users against an external authenticator (e.g. RADIUS server, or a custom 
REST API) and at the time of login, the user does not necessarily have a 
profile/account within keycloak.

My initial scan suggests that we just need to create an Authenticator 
Provider - but I'm concerned that since the user account does not 
necessarily exist in KC, I can't see how the Authenticator provider will 
work. Should I be looking at a userFederation provider instead? Looking at 
the server-spi module, I'm not seeing the Interface(s) to implement, so any 
pointers gratefuilly received!

Regards,

  Simon