[sync-services-developers] syncing only some Address Book groups

[Martin Redington]

This is probably the most frequent feature request from my users.

I hadn't really looked into filters until now, but my first naive
idea, having looked at the docs, is to grab a truth snapshot of the
relevant data, and to have my filter inspect the pulled records, and
walk up to the parent, to determine whether they belong to a group
that should be synced or not.

My understanding is that  filter only work when pulling, so I would
add similar logic to the pushing side of my app (although actually I
might not need to, as I will already  have filtered them out when
pulling [from a different truth store]).

Does this sound viable, or am I on the wrong track? Has anyone else
tried to do this, or anything like it?

What happens if someone enables a group that  has previously been
unsynced. Will they get all the updates that they're missing (i.e.
that they filtered on previous syncs)?

   cheers,
         Martin