Re: p6: Returning the freshest response

Amos Jeffries <squid3@treenet.co.nz> Sun, 31 March 2013 00:32 UTC

Return-Path: <ietf-http-wg-request@listhub.w3.org>
X-Original-To: ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com
Delivered-To: ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id D12C721F8714 for <ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com>; Sat, 30 Mar 2013 17:32:13 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -10.599
X-Spam-Level:
X-Spam-Status: No, score=-10.599 tagged_above=-999 required=5 tests=[BAYES_00=-2.599, RCVD_IN_DNSWL_HI=-8]
Received: from mail.ietf.org ([12.22.58.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id IuZ+C9CG9uHc for <ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com>; Sat, 30 Mar 2013 17:32:13 -0700 (PDT)
Received: from frink.w3.org (frink.w3.org [128.30.52.56]) by ietfa.amsl.com (Postfix) with ESMTP id 5A98E21F86D2 for <httpbisa-archive-bis2Juki@lists.ietf.org>; Sat, 30 Mar 2013 17:32:13 -0700 (PDT)
Received: from lists by frink.w3.org with local (Exim 4.72) (envelope-from <ietf-http-wg-request@listhub.w3.org>) id 1UM6Ah-0000x1-CN for ietf-http-wg-dist@listhub.w3.org; Sun, 31 Mar 2013 00:30:55 +0000
Resent-Date: Sun, 31 Mar 2013 00:30:55 +0000
Resent-Message-Id: <E1UM6Ah-0000x1-CN@frink.w3.org>
Received: from maggie.w3.org ([128.30.52.39]) by frink.w3.org with esmtp (Exim 4.72) (envelope-from <squid3@treenet.co.nz>) id 1UM6AU-0000vQ-Kt for ietf-http-wg@listhub.w3.org; Sun, 31 Mar 2013 00:30:42 +0000
Received: from ip-58-28-153-233.static-xdsl.xnet.co.nz ([58.28.153.233] helo=treenet.co.nz) by maggie.w3.org with esmtp (Exim 4.72) (envelope-from <squid3@treenet.co.nz>) id 1UM6AT-0008LB-1G for ietf-http-wg@w3.org; Sun, 31 Mar 2013 00:30:42 +0000
Received: from [192.168.2.7] (103-9-43-128.flip.co.nz [103.9.43.128]) by treenet.co.nz (Postfix) with ESMTP id 2F2E0E70D3 for <ietf-http-wg@w3.org>; Sun, 31 Mar 2013 12:30:14 +1200 (NZST)
Message-ID: <51578395.6070800@treenet.co.nz>
Date: Sun, 31 Mar 2013 13:30:13 +1300
From: Amos Jeffries <squid3@treenet.co.nz>
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:17.0) Gecko/20130307 Thunderbird/17.0.4
MIME-Version: 1.0
To: ietf-http-wg@w3.org
References: <E56A5FA7-555D-4283-95A1-FD0030D4616A@mnot.net> <CABkgnnXbDfXN1KA-AfHcW=macw44hK346z0UuYMZYx8OXBZv4g@mail.gmail.com>
In-Reply-To: <CABkgnnXbDfXN1KA-AfHcW=macw44hK346z0UuYMZYx8OXBZv4g@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Received-SPF: pass client-ip=58.28.153.233; envelope-from=squid3@treenet.co.nz; helo=treenet.co.nz
X-W3C-Hub-Spam-Status: No, score=-4.4
X-W3C-Hub-Spam-Report: AWL=-2.499, BAYES_00=-1.9, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001
X-W3C-Scan-Sig: maggie.w3.org 1UM6AT-0008LB-1G a54659a9b661396c9f42aaafa902377a
X-Original-To: ietf-http-wg@w3.org
Subject: Re: p6: Returning the freshest response
Archived-At: <http://www.w3.org/mid/51578395.6070800@treenet.co.nz>
Resent-From: ietf-http-wg@w3.org
X-Mailing-List: <ietf-http-wg@w3.org> archive/latest/17184
X-Loop: ietf-http-wg@w3.org
Resent-Sender: ietf-http-wg-request@w3.org
Precedence: list
List-Id: <ietf-http-wg.w3.org>
List-Help: <http://www.w3.org/Mail/>
List-Post: <mailto:ietf-http-wg@w3.org>
List-Unsubscribe: <mailto:ietf-http-wg-request@w3.org?subject=unsubscribe>

On 30/03/2013 4:47 a.m., Martin Thomson wrote:
> On 28 March 2013 20:10, Mark Nottingham <mnot@mnot.net> wrote:
>> """
>> If multiple selected responses are available, the cache will need to choose one to use. If a selecting header has a known mechanism for doing so (e.g., qvalues on Accept and similar request headers), it MAY be used to select one; otherwise, the most recent response (as determined by the Date header field) is used, as per Section 4.
>> """
> This seems good.  The "it" in "it MAY be used to select one" is
> perhaps ambiguous, but I don't see how to fix it without making it
> even harder to parse :)
>

Perhapse this is a bit better?

"

If multiple selected responses are available, the cache will need to choose one to use. When a selecting header has a known mechanism for doing so (e.g., qvalues on Accept and similar request headers), that mechanism SHOULD be used to eliminate unwanted responses; of the remainder, the most recent response (as determined by the Date header field) is used, as per Section 4.

"

Making it clear that Date mechanism still applies, but only after the 
negotiation filtering has been done. AFAIK that is how it always gets 
done in practice anyway.

Amos