On Thu, Aug 18, 2005 at 03:56:48PM -0700, Wilfredo Sánchez Vega wrote:
> The spec for If-{None-}Match and If-{Un}Modified-Since is driving
> me batty.
>
> The biggest item has to do with having to know the response code
> for the request without processing the request. Specifically, 14.24
> (If-Match) and the others have a requirement like:
>
> If the request would, without the If-Match header field,
> result in
> anything other than a 2xx status, then the If-Match header
> MUST be
> ignored.
I could make a wild guess that this is an attempt to specify some
evaluation precedence to the header; so e.g. if you know you have to
issue a 400 because the request is otherwise syntactically invalid, then
you must ignore the if-match. Likewise for a 401. But it doesn't seem
to make much sense as a MUST requirement, agreed.
> Next up, 14.25 (If-Modified-Since) implies in the first paragraph
> that it applies to all methods, but then only proceeds to describe
> what to do with a GET, and even then, a GET with no Range header. If
> I get an IMS for a PUT, is that a valid request? How about a DAV
> COPY? Presumably in that case would apply, if valid, to the source
> resource, not the destination.
Yes, it should be valid for all methods certainly - it just applies to
the resource identified by the request-uri, regardless of method; so
that is the source for a COPY and MOVE, indeed. (iirc the I-M-S/I-U-S
headers do work properly with mod_dav, but not the if-match ones)
joe
