How to get FirstName/LastName using Keycloak UserRegistrationProvider? - keycloak

Question

I am looking for any way to get the firstname or the lastname of a new self-registered user on keyclock using a User Storage Provider ?
In my case, i'm working with Keycloak 12 and an old legacy MySQL database where I have to store all my users.
Implementing into my SPI the UserRegistrationProvider.addUser(RealmModel realm, String username) and the CredentialInputUpdater.updateCredential(RealmModel realm, UserModel user, CredentialInput input) allows me to catch the username and the password ... but I can't get any other basic information such as firstname/lastname ?
Here are my two implementation of CredentialInputUpdater and UserRegistrationProvider :
#Override
public UserModel addUser(final RealmModel realmModel, final String username) {
Integer id = userRepository.createUser(username, "password");
User user = null;
if (id != null) {
user = new User(id.toString(), username, "firstName", "userName", "password");
}
return user != null ? new UserAdapter(session, realmModel, model, user) : null;
}
#Override
public boolean updateCredential(RealmModel realm, UserModel user, CredentialInput input) {
if (!supportsCredentialType(input.getType()) || !(input instanceof UserCredentialModel)) {
return false;
}
UserCredentialModel cred = (UserCredentialModel) input;
return userRepository.updateCredentials(user.getUsername(), cred.getChallengeResponse());
}
Any idea on how to get these two data ?

Answer 1

A bit late for your question, but I ran into a similar problem. My use case was the following : I had to call an external API from the addUser method while providing both username and password.
After debugging Keycloak I found out you can retrieve every parameters filled in the form inside the Keycloak session (or the context).
Here is an example for the password :
String password = this.session.getContext()
.getContextObject(HttpRequest.class)
.getDecodedFormParameters()
.getFirst("password");
Hopefully, this will help other people.

Answer 2

After some days of research, I finally found the solution.
I'm not sure if it works on keycloak 12, but it does on keycloak 18.
This comment give me the point.
So in addUser you don't have to persit the new user, you only have to create your UserAdapter and just before return UserModel I added:
javax.enterprise.inject.spi.CDI.current().getBeanManager().fireEvent(userAdapter);
and in the same class I added the event listener:
public void observeUserAddedEvent(#Observes(during = TransactionPhase.BEFORE_COMPLETION) UserModel addedUser) {
// persist the "post populated" user
}