Re: NEW PREFERENCE - vtimezone

Hi Martin,

--On June 19, 2015 at 9:56:11 AM -0700 Martin Thomson 
<> wrote:

>> Indicates whether the client prefers a CalDAV server
>>       to send "VTIMEZONE" iCalendar components in responses.
> This is a very general type of solution to what appears to be a highly
> specific problem.  Isn't this just content negotiation?  Could you use a
> MIME type?
> I understand that there might be compatibility issues, but this seems like
> a poor use of the Prefer mechanism.

Content negotiation at the HTTP level (Accept header) is not possible here 
because some of the CalDAV responses actually contain calendar data 
embedded in an overall XML response - i.e., the HTTP response is 
application/xml, that contains XML elements with text/calendar data in 
them. We want those embedded calendar data elements to be subject to the 

Of course we could just invent our own HTTP to indicate this "embedded 
data" preference, but making use of Prefer seems better in that we are 
already encouraging clients to use that (e.g., return=minimal is a very 
useful for reducing response sizes with many of the WebDAV PROPFIND and 
REPORT requests that CalDAV clients use).

Cyrus Daboo

Received on Friday, 19 June 2015 17:08:35 UTC