[keycloak-dev] Moving ClientInitialAccessModel from infinispan to db

I've sent PR https://github.com/keycloak/keycloak/pull/4248 for move ClientInitialAccessModel from userSessionProvider (infinispan) to realm model (db). This has advantages like: - Client initial access tokens will remain persistent among server restarts - There won't be issues in cross-dc environment Regarding functionality, nothing is changed. Admin console and admin REST endpoints are still the same behaviour. There is still decrease of remainingCount during each client registration like was before. Only change is, that server restarts will just work :) I didn't add support for export/import of client initial access token models. Was thinking about possible issues like: - admin creates the initial token with 3 counters - Export is done - Then token is used to register 3 clients, which defacto make the token expired - After realm re-import, the token will be back again with 3 attempts, which is likely not what admin wants. Also I didn't add support for caching. Reason is, that there is just small amount of tokens. Also there is almost same amount of writes and reads to ClientInitialAccessModel as every client registration needs to decrease counter and update DB. With caching enabled, there will be lots of additional overhead needed to send invalidation message to all cluster nodes in all DCs during every write, which likely won't help with performance, but rather the opposite. WDYT? Marek