IAuthUser

You have to create a User component which responds to the getId() method. This user will be retrieved by the retrieve methods from your IUserService

interface {

    /**
     * Return the unique identifier for the user
     */
    function getId();

    /**
     * Verify if the user has one or more of the passed in permissions
     *
     * @permission One or a list of permissions to check for access
     *
     */
    boolean function hasPermission( required permission );

    /**
     * Shortcut to verify it the user is logged in or not.
     */
    boolean function isLoggedIn();

}

Combined with cbsecurity or cbguard you might have to specify additional methods for checking roles or permissions.