Re: p1: generating "internal" errors

Willy Tarreau <w@1wt.eu> Sat, 20 April 2013 07:15 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 1F2F921F89AF for <ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com>; Sat, 20 Apr 2013 00:15:50 -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 p8CbZ26ALeH3 for <ietfarch-httpbisa-archive-bis2Juki@ietfa.amsl.com>; Sat, 20 Apr 2013 00:15:49 -0700 (PDT)
Received: from frink.w3.org (frink.w3.org [128.30.52.56]) by ietfa.amsl.com (Postfix) with ESMTP id 591FE21F874E for <httpbisa-archive-bis2Juki@lists.ietf.org>; Sat, 20 Apr 2013 00:15:49 -0700 (PDT)
Received: from lists by frink.w3.org with local (Exim 4.72) (envelope-from <ietf-http-wg-request@listhub.w3.org>) id 1UTS17-0003wD-Ir for ietf-http-wg-dist@listhub.w3.org; Sat, 20 Apr 2013 07:15:25 +0000
Resent-Date: Sat, 20 Apr 2013 07:15:25 +0000
Resent-Message-Id: <E1UTS17-0003wD-Ir@frink.w3.org>
Received: from lisa.w3.org ([128.30.52.41]) by frink.w3.org with esmtp (Exim 4.72) (envelope-from <w@1wt.eu>) id 1UTS14-0003vT-MB for ietf-http-wg@listhub.w3.org; Sat, 20 Apr 2013 07:15:22 +0000
Received: from 1wt.eu ([62.212.114.60]) by lisa.w3.org with esmtp (Exim 4.72) (envelope-from <w@1wt.eu>) id 1UTS14-0003C6-0V for ietf-http-wg@w3.org; Sat, 20 Apr 2013 07:15:22 +0000
Received: (from willy@localhost) by mail.home.local (8.14.4/8.14.4/Submit) id r3K7Exqs028650; Sat, 20 Apr 2013 09:14:59 +0200
Date: Sat, 20 Apr 2013 09:14:59 +0200
From: Willy Tarreau <w@1wt.eu>
To: Mark Nottingham <mnot@mnot.net>
Cc: "ietf-http-wg@w3.org Group" <ietf-http-wg@w3.org>
Message-ID: <20130420071459.GJ26517@1wt.eu>
References: <EA721AC2-5655-4EC6-851B-303EE22BB670@mnot.net> <20130420070354.GH26517@1wt.eu> <508475A0-4D1A-491B-AB1F-D9D1D9525D35@mnot.net>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <508475A0-4D1A-491B-AB1F-D9D1D9525D35@mnot.net>
User-Agent: Mutt/1.4.2.3i
Received-SPF: pass client-ip=62.212.114.60; envelope-from=w@1wt.eu; helo=1wt.eu
X-W3C-Hub-Spam-Status: No, score=-3.4
X-W3C-Hub-Spam-Report: AWL=-2.692, RP_MATCHES_RCVD=-0.702, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001
X-W3C-Scan-Sig: lisa.w3.org 1UTS14-0003C6-0V 3685146cb442fbe4b93409aa2c0a103e
X-Original-To: ietf-http-wg@w3.org
Subject: Re: p1: generating "internal" errors
Archived-At: <http://www.w3.org/mid/20130420071459.GJ26517@1wt.eu>
Resent-From: ietf-http-wg@w3.org
X-Mailing-List: <ietf-http-wg@w3.org> archive/latest/17394
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 Sat, Apr 20, 2013 at 05:06:08PM +1000, Mark Nottingham wrote:
> 
> On 20/04/2013, at 5:03 PM, Willy Tarreau <w@1wt.eu> wrote:
> 
> > On Sat, Apr 20, 2013 at 02:07:52PM +1000, Mark Nottingham wrote:
> >> p1 3.2.4 requires that a syntax violation in a received response be turned
> >> into a 502 (Bad Gateway) status code.
> >> 
> >> I'm not necessarily against it, but I think if we're going to take this
> >> approach to errors in received responses, it should be systematic, and we
> >> should recommend that others do it too. Currently, a lot of people are
> >> inventing new pseudo status codes to fill this role.
> >> 
> >> What do people think?
> > 
> > haproxy does exactly this right now (502) and I was not aware that people
> > invent their own code, this is pretty bad :-(
> 
> I'm thinking more about client libraries than intermediaries.

OK. As was once discussed here, if we insist on no status code in the range
100-599 to be randomly picked by a developer, we're leaving enough room for
libraries to do what they want without risk of interference.

> >> This might not result in any changes in our specs beyond adjusting language
> >> in a few other places to do the same thing. I could see writing a separate
> >> spec for a header that described the type of error, though.
> > 
> > Good idea. Alternatively the reason code after the 502 could be modulated too.
> 
> That is discarded in some circumstances, and in any case we shouldn't
> encourage people to start using it for semantically significant things...

Agreed.

Willy