Recurring events in CalDAV

At last week's calendaring BOF at Etech, folks asked how CalDAV treats recurring events. I had to embarrassingly admit that I didn't know the answer. Just because I'm evangelizing calendaring interoperability doesn't mean I've actually read the spec! (he says sheepishly).

So for those who want to know, from the latest draft of the CalDAV spec - the answer is that recurring events are treated as a single object in CalDAV:

 Recurrence is an important part of the data model because it governs
   how many resources are expected to exist.  This specification models
   a recurring calendar component and its recurrence exceptions as a
   single resource.  In this model, recurrence rules, recurrence dates,
   exception rules, and exception dates are all part of the data in a
   single calendar object resource.  This model avoids problems of
   limiting how many recurrence instances to store in the repository,
   how to keep recurrence instances in sync with the recurring calendar
   component, and how to link recurrence exceptions with the recurring
   calendar component.  It also results in less data to synchronize
   between client and server, and makes it easier to make changes to all
   recurrence instances or to a recurrence rule.  It makes it easier to
   create a recurring calendar component, and easier to delete all
   recurrence instances.

   Clients are not forced to retrieve information about all recurrence

   instances of a recurring component.  The CALDAV:calendar-query and

   CALDAV:calendar-multiget REPORTs defined in this document allow

   clients to retrieve only recurrence instances that overlap a given

   time range.

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