Hidden feature: CardDAV for system users incl. federated servers (oC 9.0+)



Just a small hint as it seems that oC 9+ contains yet another hidden feature which is not documented (as quite often):

Always wondering what the following command is used for:

occ dav:sync-system-addressbook

The docs itself about it is not really descriptive:

Synchronizes users to the system addressbook

After digging around it seems this was introduced by @DeepDiver1975 in https://github.com/owncloud/core/pull/20719

However the documentation for this and the usage is completely missing. It seems one can attach an external CardDAV client to:


and is getting the users existing in the ownCloud installations as Contacts / VCARDs.

You can even sync these addressbooks over federated Clouds with oC 9: https://github.com/owncloud/core/pull/20948

occ federation:sync-addressbooks

Ref for a request to document this: