[Ietf-caldav] CalDAV Global Address Book

[Julian Reschke]

Cyrus Daboo schrieb:
> Hi Kervin,
> 
> --On June 26, 2006 9:09:03 AM +0200 Julian Reschke 
> <julian.reschke at gmx.de> wrote:
> 
>>> (i) Is it reasonable to assume that the principal
>>> collection would allow listing?  In my current
>>> testing this has been the case.  Ie. Are we
>>> going to incur the wrath of Sys. Admins. because
>>> we assumed that users are allowed to list this
>>> collection?  ( I am hoping someone more familiar
>>> with WebDAV ACL can clarify this )
>>
>> No, in general you can't assume that listing will work, as the
>> collections may be very (very!) big.
>>
>> But the DAV:principal-property-search REPORT may help here
>> (<http://greenbytes.de/tech/webdav/rfc3744.html#rfc.section.9.4>).
> 
> There are situations where access to the principal hierarchy may be 
> denied entirely (whether directly or by a REPORT). For example, consider 
> an ISP running a caldav server - they are very unlikely to want to 
> expose their customer list (list of users) to everyone either outsiders 
> or customers.
> 
> Question: is your intent here to have a general way to find anybody's 
> calendar given some identifier? Do you actually want their calendar as 
> opposed to wanting to do scheduling operations with them (as in 
> free-busy lookups, booking meetings etc)? If this is what you want to do 
> then there have been several discussions of 'calendar user 
> discoverability' that have gone on in Calconnect. Right now the feeling 
> is that there needs to be a new 'scheduleto' URI scheme with appropriate 
> lookup rules (SRV records) to find the calendar service for a particular 
> address.

Why a new *URI scheme*???????? Common (well...) wisdom IMHO is not to 
define new URI schemes, unless none of the existing schemes would work. 
Why wouldn't http be sufficient? Did you consider defining a MIME type 
(holding the information in the content), or a link relation?

Best regards, Julian