Copy of the SSH key happens only during install

[Benjamin Allot]

The "copy_user_key" method is only called upon "install" hook

  @hooks.hook("install")
  def install():
      setup_udldap()
      copy_user_keys()
      reconfigure_sshd()

This means that every time a key is refreshed somehow by any other means, we never refresh it.

I guess it shall be called upon update-status and be a noop operation if there is no difference and only append key, not delete any.

This way if something else (say a nova-compute charm) refresh some ssh keys, they are refreshed automatically.

Arguably this could be handled by the nova-compute charm itself but I fear this is going to collide, so the "append only" feature makes sense anyway.

[Drew Freiberger (afreiberger)]

This is definitely an issue, and why we've stopped deploying to cloud nodes, it breaks nova migration due to the key copying.

I think we might be better off having a list of users that sshd uses ~/.ssh/authorized_keys for, instead of forcing all user keys to /var/lib/misc/ or /etc/ssh/user-authorized-keys, rather than having to have a cron to keep up with variable auth-keys files.

[Eric Chen (eric-chen)]

Migrate to https://github.com/canonical/charm-userdir-ldap/issues/3