Re: [netmod] Text in import to indicate whether a module is needed as import-only or as implemented

Ladislav Lhotka <lhotka@nic.cz> Thu, 19 December 2019 16:00 UTC

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From: Ladislav Lhotka <lhotka@nic.cz>
To: netmod@ietf.org
Date: Thu, 19 Dec 2019 17:00:18 +0100
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Subject: Re: [netmod] Text in import to indicate whether a module is needed as import-only or as implemented
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On Thu, 2019-12-19 at 07:52 +0000, Schönwälder, Jürgen wrote:
> On Thu, Dec 19, 2019 at 08:23:27AM +0100, Ladislav Lhotka wrote:
> > I don't see how YANG syntax defines this. If a module imports ietf-netconf-
> > acm, it could be because
> > 
> > - it just uses a typedef, such as "node-instance-identifier", and then
> >   ietf-netconf-acm needn't be implemented (but can be),
> > 
> > or
> > 
> > - it augments ietf-netconf-acm, which makes sense only if the latter
> >   module is implemented.
> > 
> > It it the YANG library that specifies whether a module is implemented or
> > not, but the "import" statement itself doesn't tell you anything.
> > 
> 
> Can we not assume that an implementor will figure out the difference?

An implementor should be able to figure it out, but other potential module users
may not. For example, if somebody is evaluating whether to use a module for
their device or not, it is important to know that NACM has to be implemented (or
not).

Lada

> Or someone writes a pyang plugin to determine from the schema tree the
> kind of imports there are (for a given set of features).
> 
> /js
> 
-- 
Ladislav Lhotka
Head, CZ.NIC Labs
PGP Key ID: 0xB8F92B08A9F76C67