RE: conditional methods and WebDAV

It is my understanding that to be a HTTP compliant server
the server
MUST honor the if header on ALL methods (including Webdav).

The open issue IMHO is, does the IF header relate to just
the URI, or
does it relate to every resource the method touches (DEPTH
infinity or a
DELETE can touch LOTS of objects for instance).  I do not
remember if
this was ever decided (its been a while) but I would bet
this could
behave differently depending on the server.

Kevin

-----Original Message-----
From: w3c-dist-auth-requestw3.org
[mailto:w3c-dist-auth-requestw3.org]
On Behalf Of Arnaud Quillaud
Sent: Wednesday, August 08, 2007 9:30 AM
To: w3c-dist-authw3.org
Subject: conditional methods and WebDAV


Hello,

HTTP defines a few conditional headers (if-* headers) and so
does WebDAV
(if header). In both cases those headers can be used
"to make *a* method
conditional". There is no table listing which method
can be made
conditional.
By reading between the lines one can guess that the if-*
headers main
purpose is for GET/PUT methods while if can be applied to
pretty much
any method but that is about it.

This brings up a few questions:
* is the choice to make one method conditional or not left
to server
implementations ?
* how can a client discover whether a particular method
honor one of the
if* headers (e.g. DELETE with if-match, PROPPATCH with
if-unmodified-since or PROPFIND with if-modified-since) ?
* should the WebDAV if header be honored on all
HTTP/WebDAV/*DAV methods
?

Thanks,

Arnaud Q