From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by dcvr.yhbt.net (Postfix) with ESMTP id E711D1F66E for ; Fri, 14 Aug 2020 20:47:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726362AbgHNUrd (ORCPT ); Fri, 14 Aug 2020 16:47:33 -0400 Received: from pb-smtp2.pobox.com ([64.147.108.71]:52050 "EHLO pb-smtp2.pobox.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726270AbgHNUrd (ORCPT ); Fri, 14 Aug 2020 16:47:33 -0400 Received: from pb-smtp2.pobox.com (unknown [127.0.0.1]) by pb-smtp2.pobox.com (Postfix) with ESMTP id 5C29A6C420; Fri, 14 Aug 2020 16:47:31 -0400 (EDT) (envelope-from junio@pobox.com) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type:content-transfer-encoding; s=sasl; bh=TAWVzz1euwqA QLRHLum8Dh/EiRQ=; b=PoqStWzjWXIBBDwhiu6LCwo6YiXAy+FMhmqm1UFBUEta eNTB8ipXy/NHy4e6TSb41mzMIY4m0g/h3AjPWypPImhSMp0MvcMxID9J+p4/qoMP Sm9sIdIJEpbGO1U/WkYsQdGGAN+XUPJ4Sh3znLbv81K+THRMoYx7yFgkmTXdGc8= DomainKey-Signature: a=rsa-sha1; c=nofws; d=pobox.com; h=from:to:cc :subject:references:date:in-reply-to:message-id:mime-version :content-type:content-transfer-encoding; q=dns; s=sasl; b=SFqAxU uzUGekkSMwdFAm09b8uZAANOzzB3XcMUeWxZwVQOsIstuEEKtLcM01IAKwrdwH6r LFJ3EwjHAY2q3f62Z+23Cn8IJBL9N3ToUhat+AT+VdBvHub++nzGsDmtGIza3ju2 gKDkCSa3XrabujbmztCYCoIO4MaxrW8Ux4PyA= Received: from pb-smtp2.nyi.icgroup.com (unknown [127.0.0.1]) by pb-smtp2.pobox.com (Postfix) with ESMTP id 533506C41F; Fri, 14 Aug 2020 16:47:31 -0400 (EDT) (envelope-from junio@pobox.com) Received: from pobox.com (unknown [35.231.104.69]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by pb-smtp2.pobox.com (Postfix) with ESMTPSA id D1E2B6C41D; Fri, 14 Aug 2020 16:47:30 -0400 (EDT) (envelope-from junio@pobox.com) From: Junio C Hamano To: "brian m. carlson" Cc: Martin =?utf-8?Q?=C3=85gren?= , git@vger.kernel.org, Derrick Stolee Subject: Re: [PATCH 1/5] http-protocol.txt: document SHA-256 "want"/"have" format References: <20200813224901.2652387-1-sandals@crustytoothpaste.net> <5590a68c5ba7081cd7e64c708b5c25db23f5e95b.1597406877.git.martin.agren@gmail.com> <20200814202347.GN8085@camp.crustytoothpaste.net> Date: Fri, 14 Aug 2020 13:47:30 -0700 In-Reply-To: (Junio C. Hamano's message of "Fri, 14 Aug 2020 13:39:37 -0700") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 X-Pobox-Relay-ID: 5F3D0376-DE6F-11EA-8853-2F5D23BA3BAF-77302942!pb-smtp2.pobox.com Content-Transfer-Encoding: quoted-printable Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Junio C Hamano writes: > "brian m. carlson" writes: > >> On 2020-08-14 at 17:28:27, Junio C Hamano wrote: >>> Martin =C3=85gren writes: >>>=20 >>> > Document that in SHA-1 repositories, we use SHA-1 for "want"s and >>> > "have"s, and in SHA-256 repositories, we use SHA-256. >>>=20 >>> Ehh, doesn't this directly contradict the transition plan of "on the >>> wire everything will use SHA-1 version for now?" >> >> SHA-256 repositories interoperate currently using SHA-256 object IDs. >> It was originally intended that we wouldn't update the protocol, but >> that leads to much of the testsuite failing since it's impossible to >> move objects from one place to another. >> >> If we wanted to be more pedantically correct and optimize for the >> future, we could say that the values use the format negotiated by the >> "object-format" protocol extension and SHA-1 otherwise. Yes, that's wonderful. I was confused when I said about the evolution path. We still would want to eventually do the on-the-fly migration over the wire to make SHA-1 and SHA-256 repositories interoperate, but at least we already can allow SHA-256 repositories safely attempt to talk to SHA-1 repositories and gracefully fail. Thanks.