WGLC p6 4.2.1
"Adrien W. de Croy" <adrien@qbik.com> Sun, 17 March 2013 22:41 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 2846221F8B18 for <ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com>; Sun, 17 Mar 2013 15:41:25 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -10.014
X-Spam-Level:
X-Spam-Status: No, score=-10.014 tagged_above=-999 required=5 tests=[AWL=0.584, BAYES_00=-2.599, HTML_MESSAGE=0.001, 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 WVQMWekgvAn5 for <ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com>; Sun, 17 Mar 2013 15:41:23 -0700 (PDT)
Received: from frink.w3.org (frink.w3.org [128.30.52.56]) by ietfa.amsl.com (Postfix) with ESMTP id 8E2CC21F8A43 for <httpbisa-archive-bis2Juki@lists.ietf.org>; Sun, 17 Mar 2013 15:41:23 -0700 (PDT)
Received: from lists by frink.w3.org with local (Exim 4.72) (envelope-from <ietf-http-wg-request@listhub.w3.org>) id 1UHMFK-0000um-Ui for ietf-http-wg-dist@listhub.w3.org; Sun, 17 Mar 2013 22:40:06 +0000
Resent-Date: Sun, 17 Mar 2013 22:40:06 +0000
Resent-Message-Id: <E1UHMFK-0000um-Ui@frink.w3.org>
Received: from lisa.w3.org ([128.30.52.41]) by frink.w3.org with esmtp (Exim 4.72) (envelope-from <adrien@qbik.com>) id 1UHMEz-000838-3h for ietf-http-wg@listhub.w3.org; Sun, 17 Mar 2013 22:39:45 +0000
Received: from smtp.qbik.com ([210.55.214.35]) by lisa.w3.org with esmtp (Exim 4.72) (envelope-from <adrien@qbik.com>) id 1UHMEy-0001ct-8w for ietf-http-wg@w3.org; Sun, 17 Mar 2013 22:39:45 +0000
Received: From [192.168.0.10] (unverified [192.168.0.10]) by SMTP Server [192.168.0.1] (WinGate SMTP Receiver v7.5.0 (Build 3512)) with SMTP id <0019581080@smtp.qbik.com>; Mon, 18 Mar 2013 11:39:22 +1300
From: "Adrien W. de Croy" <adrien@qbik.com>
To: IETF HTTP Working Group <ietf-http-wg@w3.org>
Date: Sun, 17 Mar 2013 22:39:21 +0000
Content-Type: multipart/alternative; boundary="------=_MB35EA5939-D5EF-4CF5-A41A-11A5CEBFEBDF"
Message-Id: <em2a931273-ea65-4c5c-83d3-2d9698e19de0@bombed>
Mime-Version: 1.0
Reply-To: "Adrien W. de Croy" <adrien@qbik.com>
User-Agent: eM_Client/5.0.17595.0
Received-SPF: pass client-ip=210.55.214.35; envelope-from=adrien@qbik.com; helo=smtp.qbik.com
X-W3C-Hub-Spam-Status: No, score=-5.6
X-W3C-Hub-Spam-Report: AWL=-1.219, BAYES_00=-1.9, HTML_MESSAGE=0.001, RP_MATCHES_RCVD=-2.497, SPF_PASS=-0.001
X-W3C-Scan-Sig: lisa.w3.org 1UHMEy-0001ct-8w 7f9099b0a62729a2245335b261648f44
X-Original-To: ietf-http-wg@w3.org
Subject: WGLC p6 4.2.1
Archived-At: <http://www.w3.org/mid/em2a931273-ea65-4c5c-83d3-2d9698e19de0@bombed>
Resent-From: ietf-http-wg@w3.org
X-Mailing-List: <ietf-http-wg@w3.org> archive/latest/17046
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>
Hi all I see there were some changes made to the 3rd bullet point in 4.2.1 about selection of representations to update with a 304. The new text hints that dates other than those received in a previous Last-Modified can be used to generate a conditional request with If-Modified-Since. However, there are a number of side-effects with introducing this concept. The previous iterations of the spec requires that If-Modified-Since may only contain the content of a previously received Last-Modified. I don't know if it's wise to open this up. We would need to consider what the side-effects of choosing any other date may be. For instance if the sender (revalidating client) just chose the file date on the file in their store, it could bear no resemblance to any time on the server, and may appear to be a more recent copy than they actually have. A server could then send a 304 back for content that was no longer valid. So I think the date used in If-Modified-Since needs to have originally come from the server. This only leaves Last-Modified, and Date. Date could have been altered by intermediaries, so actually I feel it's unsafe to allow any other value than that contained in Last-Modified. My original query about this point, which I suspect was a contributing factor to this change, was concerning receiving a 304 response to a request that related to revalidating a stored entry that had no validators. My point at the time was that a 304 response to a non-conditional request is a server bug. I would argue that constructing validators in a request where none were previously received is not valid (client can't invent ETag, and shouldn't invent Last-Modified), and so therefore my proposal was to strike this altogether, or prohibit it. Regards Adrien
- WGLC p6 4.2.1 Adrien W. de Croy
- Re: WGLC p6 4.2.1 Poul-Henning Kamp
- Re: WGLC p6 4.2.1 Amos Jeffries
- Re: WGLC p6 4.2.1 Adrien W. de Croy
- Re: WGLC p6 4.2.1 Poul-Henning Kamp
- Re: WGLC p6 4.2.1 Adrien W. de Croy
- Re: WGLC p6 4.2.1 Poul-Henning Kamp
- Re: WGLC p6 4.2.1 Adrien W. de Croy
- Re: WGLC p6 4.2.1 Poul-Henning Kamp
- Re: WGLC p6 4.2.1 Fabian Keil
- Re: WGLC p6 4.2.1 Roy T. Fielding
- Re: WGLC p6 4.2.1 Mark Nottingham
- Re: WGLC p6 4.2.1 Adrien W. de Croy