IETF Logo Mail Archive

[Extra] IMAP4rev2, SEARCH CHARSET

Arnt Gulbrandsen <arnt@gulbrandsen.priv.no> Thu, 07 November 2019 10:39 UTC

Return-Path: <arnt@gulbrandsen.priv.no>
X-Original-To: extra@ietfa.amsl.com
Delivered-To: extra@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 4053E120106 for <extra@ietfa.amsl.com>; Thu, 7 Nov 2019 02:39:10 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.998
X-Spam-Level:
X-Spam-Status: No, score=-1.998 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, SPF_HELO_NONE=0.001, SPF_NONE=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=gulbrandsen.priv.no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id vyqsqpur6DBu for <extra@ietfa.amsl.com>; Thu, 7 Nov 2019 02:39:08 -0800 (PST)
Received: from stabil.gulbrandsen.priv.no (stabil.gulbrandsen.priv.no [144.76.73.169]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 6B944120103 for <extra@ietf.org>; Thu, 7 Nov 2019 02:39:08 -0800 (PST)
Received: from stabil.gulbrandsen.priv.no (stabil.gulbrandsen.priv.no [IPv6:2a01:4f8:191:91a8::3]) by stabil.gulbrandsen.priv.no (Postfix) with ESMTP id 4E9EEC001E; Thu, 7 Nov 2019 10:42:50 +0000 (GMT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gulbrandsen.priv.no; s=mail; t=1573123370; bh=PHExspEeGtGlFIMoRFlPt5KXxSdPJyg5SNaTHxDNtqk=; h=From:To:Subject:Date:From; b=FfvaJWlx+m43mvRiUVzcVhwUqMCEpdLsVSaoI0La/z6+cif+qXYaNDwTIosx/3gM7 LBSh5xjV3IGqXGMCry/2oL6fVL462KAtBAlZyORSXE7yH9fEi1jvMIUlbRp3PPfThe zYDZRbpFka9zgyU2pW7MfrLgfUn7WJiBYgwpzNYE=
Received: from arnt@gulbrandsen.priv.no by stabil.gulbrandsen.priv.no (Archiveopteryx 3.2.0) with esmtpsa id 1573123369-28749-28747/9/3; Thu, 7 Nov 2019 10:42:49 +0000
From: Arnt Gulbrandsen <arnt@gulbrandsen.priv.no>
To: extra@ietf.org
Date: Thu, 07 Nov 2019 11:39:03 +0100
Mime-Version: 1.0
Message-Id: <eb04c57f-682c-430c-b644-458fb704c48d@gulbrandsen.priv.no>
User-Agent: Trojita/0.7; Qt/5.7.1; xcb; Linux; Devuan GNU/Linux 2.1 (ascii)
Content-Type: text/plain; charset="utf-8"; format="flowed"
Archived-At: <https://mailarchive.ietf.org/arch/msg/extra/4Lli7CztFvvBMP6krDoumc4x82o>
Subject: [Extra] IMAP4rev2, SEARCH CHARSET
X-BeenThere: extra@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Email mailstore and eXtensions To Revise or Amend <extra.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/extra>, <mailto:extra-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/extra/>
List-Post: <mailto:extra@ietf.org>
List-Help: <mailto:extra-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/extra>, <mailto:extra-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 07 Nov 2019 10:39:10 -0000

Hi,

SEARCH CHARSET is a bit ungood now.

IMAP4rev1 used ASCII generally, and the CHARSET specification could be used 
to use something else in a search key. However, IMAP4rev2 now uses UTF-8 
generally (see section 4.3.1), and so CHARSET becomes rather odd.

I suggest obsoleting CHARSET and telling clients to use UTF-8 for searches. 
Suggested text (for 6.4.4):

"In IMAP4rev1, the client could specify the character encoding of non-ASCII 
search keys using SEARCH CHARSET. In IMAP4rev2, the client uses UTF-8 for 
all search keys, and for this reason CHARSET is now obsolete."

My question is: Obsolete CHARSET and say clients MUST NOT use it, or 
obsolete it and say that servers MUST support CHARSET UTF-8 and MAY support 
others?

Arnt

v2.23.0 | Report a Bug | By Email