[keycloak-user] How to migrate users and roles from in-house storage

Hi all, I'm in the process of migrating from an in-house user-role storage to Keycloak and I'm looking for programmatic (Java) ways to migrate all current users to the new storage. And I need your help to figure out the best approach. At first, when reading KC documentation, I believed I could easily achieve this by implementing a User Federation provider but after diving a little more into it, and looking for examples, I can't see a way to migrate all users on-demand but simply one user at a time, possible during log-in. Next, I tried and look into ways, such as admin-cli, REST, etc but nothing strikes me as the solution to use. Here's what I was hoping to deliver: * Get all roles and users from my soon-to-be deprecated storage, e.g. MySQL tables * Add roles to KC * Iterate users and add user to KC + map roles + update password hashes (here I know I need to implement a HashProvider) Any hints will be appreciated! Pires