Subject: draft-fielding-http-key-02 obvious shortcoming & failure

From: Henrik Nordström <[email-masked]>
Date: Thu, 25 Jul 2013 20:39:06 +0200

Learnt about the Key draft today in another discussion about how to
cache Vary responses, and reading the document I see a noticeble
shortcoming and failure of the proposed algorithm.

In "2.2.4. "p": Parameter Prefix Match Modifier" you have

Key: Accept;p="text/html"

And a seemingly nice looking list of things it matches and do not match.
So far so good. But it will also match

Accept: text/plain;q=0

which is the opposite. Here the client says it do not accept text/plain.

same issue applies to any other header using quality attribute.

It also fails to represent quality selection among different variants in
general. I.e. when there is both text/html and text/plain versions and
one client prefers plain, the other html but both can process both.

Regards
Henrik

---

From: Mark Nottingham <[email-masked]>
Date: Sun, 28 Jul 2013 08:50:15 +0200

Hi Henrik,

Yes, we're aware of that. 

We're trying to find the right level of complexity and capability for the draft, and biased towards "simple" very early. As we get some implementation experience and evolve the draft, we'll address this.

Cheers,

--
Mark Nottingham   http://www.mnot.net/