[keycloak-user] Custom Authenticator development

Hi All. I try to develop custom authentication module for Keycloak server. According to requirements I need to validate not only login/password but one more attribute - siteId, which indicates the country domain of the application. I implemented factory and *SiteIdAuthenticator extends **UsernamePasswordForm* In my *action *method I check all needed credential and if it's OK, I create new user account. (Or if user already exists, just fetch its account and add it to AuthenticationFlowContext ) validateUserAndPassword(AuthenticationFlowContext context, MultivaluedMap<String, String> inputData) { ... UserModel userById = context.getSession().userLocalStorage().getUserById(userId, context.getRealm()); if(userById == null) { logger.info("add new user:" + userId); UserModel userModel = context.getSession().userLocalStorage().addUser(context.getRealm(), userId, userName, true, false); context.setUser(userModel); } else { logger.info("user exists:" + userId); context.setUser(userById); } ... } My question is - Do I really have to add new user account to user storage? Because in Keycloak version 2.5.1 there is a posibiliti of non-importing user fedration. So maybe it is somehow possible to implement custom Authenticator without creating new user account in Keycloaks storage? Thanks in advice, Pavel