Re: New Version Notification for draft-nottingham-http-availability-hints-00.txt

[Glenn Strauss <[e-mail]>]

What about replacing "Accept-" in request from client
with "Vary-" in response from server?  This might indicate
to the client (or intermediate proxy) how the server might
"vary" responses for that vector.  A client might choose to
look at Vary-* only for related items listed in Vary.

This might extend to Vary-User-Agent, though that does not
begin with Accept-*.  (If Accept-*, then Vary-* without
repeating the Accept-, e.g. not Vary-Accept-Encoding).

BTW, the draft does not highlight that "Accept-" prefix for
items in the Vary response header is not included in the name
of the corresponding "Avail-*" response header.

Cheers, Glenn

On Mon, Mar 13, 2023 at 09:16:13PM +0100, Asbjørn Ulsberg wrote:
> I too like the spec. I’m also +1 with Mike on the “Avail” prefix. If we want to save characters, can’t “Has” work instead? “Has-Encoding”, and “Has-Language” sounds good to me, at least.
> 
> --
> Asbjørn Ulsberg    -=|=-    [e-mail]
> «He's a loathsome offensive brute, yet I can't look away»
> On 13 Mar 2023, 19:37 +0100, Mike Bishop <[e-mail]>, wrote:
> > Broadly, I like it.  I think Variants had a lot of potential to improve caching and am disappointed it hasn’t made more progress; this might be an easier way to approach the problem.
> >
> > It seems like you’re moving in a direction where:
> >
> > • These headers are always lists
> > • Equivalence classes MAY be indicated by including a sublist as a list element, for axes where it’s possible for different values to produce identical responses
> > • One list element MAY be indicated as default, for axes where a default makes sense and isn’t already implicit
> >
> >
> > It’d be nice to be able to define this more generally, but you may be on the right track that many of the Accept-* headers have enough individual quirks that they’ll all have to be separately defined.
> >
> > Minor nits:
> >
> > • I’m unenthused by “Avail” as a prefix here, purely because it’s an actual word that isn’t actually what you mean.  Do we really need to save those four characters?
> > • 5.3, Avail-Format => Avail-Language
> >
> >
> > From: Mark Nottingham <[e-mail]>
> > Sent: Saturday, March 11, 2023 9:49 PM
> > To: HTTP Working Group <[e-mail]>
> > Subject: Fwd: New Version Notification for draft-nottingham-http-availability-hints-00.txt
> >
> > FYI - this is a draft that I think is suitable for replacing the Variants specification. It conveys roughly the same information, but in a much more simple and intuitive way. Many parts are just sketched out to be filled in later, but it should be possible to get the general idea being proposed.
> >
> > Thoughts? If there's interest, I might ask for five minutes in Yokohama to talk about adoption.
> >
> > Cheers,
> >
> >
> >
> > > Begin forwarded message:
> > >
> > > From: [e-mail]
> > > Subject: New Version Notification for draft-nottingham-http-availability-hints-00.txt
> > > Date: 12 March 2023 at 1:47:09 pm AEDT
> > > To: "Mark Nottingham" <[e-mail]>
> > >
> > >
> > > A new version of I-D, draft-nottingham-http-availability-hints-00.txt
> > > has been successfully submitted by Mark Nottingham and posted to the
> > > IETF repository.
> > >
> > > Name:                  draft-nottingham-http-availability-hints
> > > Revision:              00
> > > Title:                     HTTP Availability Hints
> > > Document date:               2023-03-11
> > > Group:                  Individual Submission
> > > Pages:                  10
> > > URL:            https://www.ietf.org/archive/id/draft-nottingham-http-availability-hints-00.txt
> > > Status:         https://datatracker.ietf.org/doc/draft-nottingham-http-availability-hints/
> > > Html:           https://www.ietf.org/archive/id/draft-nottingham-http-availability-hints-00.html
> > > Htmlized:       https://datatracker.ietf.org/doc/html/draft-nottingham-http-availability-hints
> > >
> > >
> > > Abstract:
> > >   This specification defines availability hints, a new class of HTTP
> > >   responses headers that augment the information in the Vary header
> > >   field.
> > >
> > >
> > >
> > >
> > > The IETF Secretariat
> > >
> >
> > --
> > Mark Nottingham   https://www.mnot.net/
> >