Re: p6: Returning the freshest response

Martin Thomson <martin.thomson@gmail.com> Fri, 29 March 2013 16:41 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 8935A21F9409 for <ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com>; Fri, 29 Mar 2013 09:41:00 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -10.549
X-Spam-Level:
X-Spam-Status: No, score=-10.549 tagged_above=-999 required=5 tests=[AWL=0.050, 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 fOTnfB3s+ZLq for <ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com>; Fri, 29 Mar 2013 09:40:57 -0700 (PDT)
Received: from frink.w3.org (frink.w3.org [128.30.52.56]) by ietfa.amsl.com (Postfix) with ESMTP id A968F21F9405 for <httpbisa-archive-bis2Juki@lists.ietf.org>; Fri, 29 Mar 2013 09:40:57 -0700 (PDT)
Received: from lists by frink.w3.org with local (Exim 4.72) (envelope-from <ietf-http-wg-request@listhub.w3.org>) id 1ULcLR-00052V-8R for ietf-http-wg-dist@listhub.w3.org; Fri, 29 Mar 2013 16:40:01 +0000
Resent-Date: Fri, 29 Mar 2013 16:40:01 +0000
Resent-Message-Id: <E1ULcLR-00052V-8R@frink.w3.org>
Received: from maggie.w3.org ([128.30.52.39]) by frink.w3.org with esmtp (Exim 4.72) (envelope-from <martin.thomson@gmail.com>) id 1ULcLE-00050A-P9 for ietf-http-wg@listhub.w3.org; Fri, 29 Mar 2013 16:39:48 +0000
Received: from mail-we0-f179.google.com ([74.125.82.179]) by maggie.w3.org with esmtps (TLS1.0:RSA_ARCFOUR_SHA1:16) (Exim 4.72) (envelope-from <martin.thomson@gmail.com>) id 1ULcLC-0005TO-J1 for ietf-http-wg@w3.org; Fri, 29 Mar 2013 16:39:48 +0000
Received: by mail-we0-f179.google.com with SMTP id p43so469428wea.10 for <ietf-http-wg@w3.org>; Fri, 29 Mar 2013 09:39:20 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:x-received:in-reply-to:references:date:message-id :subject:from:to:cc:content-type; bh=AU55OsE9UNWVuCeKrO+MtkRcSC7Us2YSiGK870KUyzY=; b=Jb6gMmWtM6tqzVYiCs4Tb29mpSGQMZolvPmD8I+PWj33yAbD6cFxkyjch7XGQPR/8v LOF0/XQ7vvXZ6rezejJg2UvhapD4PngnC2JBmqJLe33ZC0cSyReE3D7aflJ650Ey1UGe OHccPuX/V+HU0yr0rkGCuUceLBo51dDkwWLhnDWeo7iOENJPWIAbJkDY9LI9VKcfo9hg kOiJJefzF6sIxVLAamelRvZsl9pZcQh056x8lrDGjxmtpTkIe1GsxaY4xUGNkLSVebtk yJvsWXcoEUqnSoQLlPSsqNlBiLcNzJKOkQLhxSMzPZ46uU7EJWF/X9+AtI+ziLpb+i6G eqsg==
MIME-Version: 1.0
X-Received: by 10.194.92.231 with SMTP id cp7mr4581574wjb.19.1364575160354; Fri, 29 Mar 2013 09:39:20 -0700 (PDT)
Received: by 10.194.41.35 with HTTP; Fri, 29 Mar 2013 09:39:20 -0700 (PDT)
In-Reply-To: <5155BB1C.1020703@andrew.cmu.edu>
References: <E56A5FA7-555D-4283-95A1-FD0030D4616A@mnot.net> <5155B23A.2050002@andrew.cmu.edu> <CABkgnnUc+CxTUfVvxsyJnG6pemkTpC9Z+3bQeaZbfnAdALZEtQ@mail.gmail.com> <5155BB1C.1020703@andrew.cmu.edu>
Date: Fri, 29 Mar 2013 09:39:20 -0700
Message-ID: <CABkgnnVtiRV0HNAY04nyD+h=0BEWt1ACCtGZSPNxgZ-cS9M=xA@mail.gmail.com>
From: Martin Thomson <martin.thomson@gmail.com>
To: Ken Murchison <murch@andrew.cmu.edu>
Cc: HTTP Working Group <ietf-http-wg@w3.org>
Content-Type: text/plain; charset=UTF-8
Received-SPF: pass client-ip=74.125.82.179; envelope-from=martin.thomson@gmail.com; helo=mail-we0-f179.google.com
X-W3C-Hub-Spam-Status: No, score=-3.4
X-W3C-Hub-Spam-Report: AWL=-2.636, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001
X-W3C-Scan-Sig: maggie.w3.org 1ULcLC-0005TO-J1 864565611176ad4ce67144e93c725eec
X-Original-To: ietf-http-wg@w3.org
Subject: Re: p6: Returning the freshest response
Archived-At: <http://www.w3.org/mid/CABkgnnVtiRV0HNAY04nyD+h=0BEWt1ACCtGZSPNxgZ-cS9M=xA@mail.gmail.com>
Resent-From: ietf-http-wg@w3.org
X-Mailing-List: <ietf-http-wg@w3.org> archive/latest/17177
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 29 March 2013 09:02, Ken Murchison <murch@andrew.cmu.edu> wrote:
> The current language in
> https://svn.tools.ietf.org/svn/wg/httpbis/draft-ietf-httpbis/latest/p2-semantics.html#proactive.negotiation
> (MAY) and
> https://svn.tools.ietf.org/svn/wg/httpbis/draft-ietf-httpbis/latest/p2-semantics.html#header.vary
> (SHOULD)
> don't seem to make it a requirement.  However, the SHOULD certainly suggests
> best practice.

I think that this might trigger a review comment:

The MAY is spurious, no 2119 language is needed here: the text need
only highlight that it is possible (as opposed to permissible) for a
Vary header to be present.

The SHOULD is qualified sufficiently that I believe that a MUST is
more appropriate.