I think the discussion is on the WebDAV group mailing
list, but of some interest here... see
for WebDAV WG mail.
From: Larry Masinter [mailto:LMM(_at_)acm(_dot_)org]
Sent: Thursday, March 21, 2002 11:16 AM
Subject: RE: WebDAV and Open Pluggable Edge Services
I'm reviewing the HTTP spec and the Cache-Control: no-transform
directive; RFC 2616 section 14.9.5.
To prevent transformations of authored content, servers could
respond, when the client is "authoring", with a no-transform.
But I'm less sure of the utility of the Cache-Control: no-transform
request; does it mean "don't transform the request" or does
it mean "don't transform the response?". And would it apply
to an origin server as another way of saying a kind of "translate"?
Note that authoring clients should be sensitive to
Warning 214 (Transformation applied). At least, then
there would be some belief that they wouldn't inadvertently
try to let the user edit something that wasn't the original
I'm not sure how a DAV server would know whether to supply
a cache-control: no-transform if clients distinguish between
the resource and its source by the "DAV:source" property.
(I was also wondering about the interaction between
cache-control: no-transform and the vary header. A response
with no-transform and one without no-transform are different.
So if the decision to supply no-transform depends on a request
header, then should the result Vary by that request header?)