Re: [netmod] Query about augmenting module from submodule in YANG 1.0

Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de> Wed, 09 August 2017 15:13 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 3EF651323B2 for <netmod@ietfa.amsl.com>; Wed, 9 Aug 2017 08:13:18 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.9
X-Spam-Level:
X-Spam-Status: No, score=-1.9 tagged_above=-999 required=5 tests=[BAYES_00=-1.9] 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 uj7M95o1zf4c for <netmod@ietfa.amsl.com>; Wed, 9 Aug 2017 08:13:16 -0700 (PDT)
Received: from atlas5.jacobs-university.de (atlas5.jacobs-university.de [212.201.44.20]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id D6F051323AE for <netmod@ietf.org>; Wed, 9 Aug 2017 08:13:15 -0700 (PDT)
Received: from localhost (demetrius5.irc-it.jacobs-university.de [10.70.0.222]) by atlas5.jacobs-university.de (Postfix) with ESMTP id AAFEEF6F for <netmod@ietf.org>; Wed, 9 Aug 2017 17:13:14 +0200 (CEST)
X-Virus-Scanned: amavisd-new at jacobs-university.de
Received: from atlas5.jacobs-university.de ([10.70.0.217]) by localhost (demetrius5.jacobs-university.de [10.70.0.222]) (amavisd-new, port 10032) with ESMTP id 6yl2uwRggY6K for <netmod@ietf.org>; Wed, 9 Aug 2017 17:13:13 +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 "Jacobs University CA - G01" (verified OK)) by atlas5.jacobs-university.de (Postfix) with ESMTPS for <netmod@ietf.org>; Wed, 9 Aug 2017 17:13:14 +0200 (CEST)
Received: from localhost (demetrius4.jacobs-university.de [212.201.44.49]) by hermes.jacobs-university.de (Postfix) with ESMTP id 8C446200B8 for <netmod@ietf.org>; Wed, 9 Aug 2017 17:13:14 +0200 (CEST)
X-Virus-Scanned: amavisd-new at jacobs-university.de
Received: from hermes.jacobs-university.de ([212.201.44.23]) by localhost (demetrius4.jacobs-university.de [212.201.44.32]) (amavisd-new, port 10024) with ESMTP id nx02KB2VrDtc; Wed, 9 Aug 2017 17:13:14 +0200 (CEST)
Received: from elstar.local (elstar.jacobs.jacobs-university.de [10.50.231.133]) by hermes.jacobs-university.de (Postfix) with ESMTP id 3BDD1200BA; Wed, 9 Aug 2017 17:13:14 +0200 (CEST)
Received: by elstar.local (Postfix, from userid 501) id F3147400EA3B; Wed, 9 Aug 2017 17:13:12 +0200 (CEST)
Date: Wed, 09 Aug 2017 17:13:12 +0200
From: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
To: netmod@ietf.org
Message-ID: <20170809151312.GC42207@elstar.local>
Reply-To: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
Mail-Followup-To: netmod@ietf.org
References: <E3378E0605547F4E854DEE0CB1116AB020865B@gbcdcmbx03.intl.att.com> <85A1FF5A-EF0B-4278-B4FF-3FE431486B2C@tail-f.com> <E3378E0605547F4E854DEE0CB1116AB02102DC@gbcdcmbx03.intl.att.com> <11857e8e-f46e-dc2e-cf99-80224859d221@transpacket.com> <E3378E0605547F4E854DEE0CB1116AB0210631@gbcdcmbx03.intl.att.com> <defe35bb-bb8b-f1f0-d8c4-2d2d0f23731b@transpacket.com> <1502290869.16638.15.camel@nic.cz>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
In-Reply-To: <1502290869.16638.15.camel@nic.cz>
User-Agent: Mutt/1.6.0 (2016-04-01)
Archived-At: <https://mailarchive.ietf.org/arch/msg/netmod/sQl9MWNSGEpUlLZolHH5Tkwwi7U>
Subject: Re: [netmod] Query about augmenting module from submodule in YANG 1.0
X-BeenThere: netmod@ietf.org
X-Mailman-Version: 2.1.22
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: Wed, 09 Aug 2017 15:13:18 -0000

On Wed, Aug 09, 2017 at 05:01:09PM +0200, Ladislav Lhotka wrote:
> 
> I remember that in early stages of YANG there was some irrational
> fear of introducing too many namespaces, and submodules may be a
> consequence of it. As you write, submodules provide no benefits
> whatsoever in terms of modularity, but the overhead in terms of
> metadata, IANA registration etc. is pretty much the same as for
> modules.

In case YANG 2.0 is ever done, I suggest someone files a proposal to
remove submodules if the cost/benefit ratio is at odds. There is
nothing wrong with removing stuff that has been found problematic.

The motivation for submodules was that organizations maintaining large
modules with multiple people can do so without having to mess around
with tools like m4 scripts to produce a single module from 'snippets'
and to avoid integration surprises. But perhaps using m4 scripts and
decent version control systems (that can integrate and compile on
checkin) is indeed cheaper than having submodules part of the YANG
language itself.

/js

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