IETF Logo Mail Archive

Re: [netmod] IETF 108: Summary of insignificant whitespace changes and versioning

Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de> Thu, 13 August 2020 10:23 UTC

Return-Path: <j.schoenwaelder@jacobs-university.de>
X-Original-To: netmod@ietfa.amsl.com
Delivered-To: netmod@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id DD9793A0B4D for <netmod@ietfa.amsl.com>; Thu, 13 Aug 2020 03:23:08 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.899
X-Spam-Level:
X-Spam-Status: No, score=-1.899 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=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 9hffsjWdDfdP for <netmod@ietfa.amsl.com>; Thu, 13 Aug 2020 03:23:07 -0700 (PDT)
Received: from atlas5.jacobs-university.de (atlas5.jacobs-university.de [212.201.44.20]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 155213A0AA1 for <netmod@ietf.org>; Thu, 13 Aug 2020 03:23:06 -0700 (PDT)
Received: from localhost (demetrius5.irc-it.jacobs-university.de [10.70.0.222]) by atlas5.jacobs-university.de (Postfix) with ESMTP id 89049374; Thu, 13 Aug 2020 12:23:04 +0200 (CEST)
X-Virus-Scanned: amavisd-new at jacobs-university.de
Received: from atlas5.jacobs-university.de ([10.70.0.198]) by localhost (demetrius5.jacobs-university.de [10.70.0.222]) (amavisd-new, port 10032) with ESMTP id FueuSEhbBRrz; Thu, 13 Aug 2020 12:23:04 +0200 (CEST)
Received: from hermes.jacobs-university.de (hermes.jacobs-university.de [212.201.44.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "hermes.jacobs-university.de", Issuer "DFN-Verein Global Issuing CA" (verified OK)) by atlas5.jacobs-university.de (Postfix) with ESMTPS; Thu, 13 Aug 2020 12:23:04 +0200 (CEST)
Received: from localhost (demetrius5.irc-it.jacobs-university.de [10.70.0.222]) by hermes.jacobs-university.de (Postfix) with ESMTP id 13AAB20154; Thu, 13 Aug 2020 12:23:04 +0200 (CEST)
X-Virus-Scanned: amavisd-new at jacobs-university.de
Received: from hermes.jacobs-university.de ([212.201.44.23]) by localhost (demetrius5.jacobs-university.de [10.70.0.222]) (amavisd-new, port 10028) with ESMTP id Txy0Pang_IzQ; Thu, 13 Aug 2020 12:23:03 +0200 (CEST)
Received: from localhost (anna.jacobs.jacobs-university.de [10.50.218.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by hermes.jacobs-university.de (Postfix) with ESMTPS id 8C04D200E4; Thu, 13 Aug 2020 12:23:03 +0200 (CEST)
Date: Thu, 13 Aug 2020 12:23:02 +0200
From: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
To: Ladislav Lhotka <ladislav.lhotka@nic.cz>
Cc: "Joe Clarke (jclarke)" <jclarke@cisco.com>, "netmod@ietf.org" <netmod@ietf.org>
Message-ID: <20200813102302.xwowkncgur4s7yuc@anna.jacobs.jacobs-university.de>
Reply-To: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
Mail-Followup-To: Ladislav Lhotka <ladislav.lhotka@nic.cz>, "Joe Clarke (jclarke)" <jclarke@cisco.com>, "netmod@ietf.org" <netmod@ietf.org>
References: <5CF24083-4126-4BE0-93F1-9A36F6DE9296@cisco.com> <20200811.164556.608015447238311339.id@4668.se> <A634B3C1-9F19-4A44-9479-56EC986DA1D8@cisco.com> <878sekb885.fsf@nic.cz> <11245BD3-6E79-4F02-9962-53BE87264460@cisco.com> <acfe1b95-e0f3-0b7e-2635-9582eb11b4e6@nic.cz>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
In-Reply-To: <acfe1b95-e0f3-0b7e-2635-9582eb11b4e6@nic.cz>
Archived-At: <https://mailarchive.ietf.org/arch/msg/netmod/MaCS-f94-X45olwaG5EbTCE4MBE>
Subject: Re: [netmod] IETF 108: Summary of insignificant whitespace changes and versioning
X-BeenThere: netmod@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: NETMOD WG list <netmod.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/netmod>, <mailto:netmod-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/netmod/>
List-Post: <mailto:netmod@ietf.org>
List-Help: <mailto:netmod-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/netmod>, <mailto:netmod-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 13 Aug 2020 10:23:09 -0000

On Thu, Aug 13, 2020 at 11:37:18AM +0200, Ladislav Lhotka wrote:
> 
> 
> $ pyang -f yin ietf-inet-types.yang | xmllint --c14n - | sha256sum
> 8d1ca8f30566ce8cbeffa095e20642f8f6e9f3a724286be4ead863b4467dc40b  -
> 
> might be a very good start. It is certainly much more robust than
> relying on a simple checksum of the YANG module text.

This work started with the need for _semantic_ version numbers and now
we are down to hashes of modules? Do we still have a clear idea which
problem we are solving?

- Sane development environments use version control systems, we should
  in my view not attempt to go there. We should assume that people
  developing YANG modules use version control systems to track
  changes.

- There apparently is a need for a packaging system that can express
  which combinations of YANG module version are known to work
  together.

The YANG versioning work was driven (I think) by the desire to
support non-backwards compatible changes (section 4 of
draft-ietf-netmod-yang-versioning-reqs-03). Why do we end up
discussing how to calculate hashes or the impact of whitespace
changes? Whitespace and layout changes are backwards compatible,
even today's YANG versioning rules handle them well.

/js

-- 
Juergen Schoenwaelder           Jacobs University Bremen gGmbH
Phone: +49 421 200 3587         Campus Ring 1 | 28759 Bremen | Germany
Fax:   +49 421 200 3103         <https://www.jacobs-university.de/>

v2.23.0 | Report a Bug | By Email