On 23/08/2017 11:09, Ivory, William wrote:
Hi Robert,
Probably shouldn't have mentioned packages as that's really a diversion from
the main point. What submodules provide is a way to differentiate YANG nodes
in a single namespace so that while still belonging to that single namespace,
subsets may be handled by different daemons simply by routing according to
submodule id. That keeps all the identifying logic within YANG.
Obviously if we could start afresh, we'd use separate modules from day one.
However, we have existing YANG that needs to remain to be backwards-compatible,
so that isn't an option.
Another potential solution that doesn't use sub modules could be to
define a bespoke YANG extension to annotate your YANG schema tree with
any necessary routing information for it to be handled by the
appropriate daemon.
Thanks,
Rob
Regards,
William
-----Original Message-----
From: Robert Wilton [mailto:[email protected]]
Sent: 23 August 2017 10:46
To: Ivory, William <[email protected]>; 'Juergen Schoenwaelder'
<[email protected]>
Cc: 'Alex Campbell' <[email protected]>; '[email protected]'
<[email protected]>
Subject: Re: [netmod] Query about augmenting module from submodule in YANG 1.0
Hi William,
I think that there might be some downsides to your proposed solution of using
submodules - which you may have already considered:
1) All of the debian packages will have to be installed together to allow the
YANG module to be built, or otherwise there will be missing submodules, and the
module will fail to compile (since the top level module must list all included
sub-modules).
2) It might end up with your requiring tight versioning of all of your debian
packages together with the same version number, or otherwise you may need
greater care over how the sub-modules are updated and dependencies are handled.
If your YANG was being designed from scratch then using separate YANG modules
may allow for a cleaner solution - but I appreciate that may not help you with
where you are now.
Thanks,
Rob
On 23/08/2017 09:24, Ivory, William wrote:
Sorry - meant Debian packages. We have a large YANG module that really ought
to be handled by multiple daemons, so plan to use submodules so we can identify
the different parts and process them in the right place. Recombining into a
single module would lose that granularity.
William
-----Original Message-----
From: Juergen Schoenwaelder
[mailto:[email protected]]
Sent: 23 August 2017 08:25
To: Ivory, William <[email protected]>
Cc: 'Alex Campbell' <[email protected]>; 'Robert Wilton'
<[email protected]>; '[email protected]' <[email protected]>
Subject: Re: [netmod] Query about augmenting module from submodule in
YANG 1.0
What are packages? I think submodules declare to which module they belong, no?
Perhaps you are doing something that submodules do not even support.
/js
On Wed, Aug 23, 2017 at 07:08:10AM +0000, Ivory, William wrote:
... except that if the whole reason for splitting into submodules was to allow
the submodules to belong to different packages in our system, combining them
back again is not possible. I wouldn't be splitting them unless I needed to
for good reason.
William
-----Original Message-----
From: Alex Campbell [mailto:[email protected]]
Sent: 22 August 2017 23:28
To: Ivory, William <[email protected]>; 'Robert Wilton'
<[email protected]>; '[email protected]' <[email protected]>
Subject: Re: [netmod] Query about augmenting module from submodule in
YANG 1.0
Hi,
I'm not Rob, but my understanding is that if a module author wanted to migrate
to YANG 2.0, they could merge their submodules back into the main module -
which is not a difficult procedure and does not break compatibility with
clients.
Alex
________________________________________
From: netmod <[email protected]> on behalf of Ivory, William
<[email protected]>
Sent: Tuesday, 22 August 2017 1:44 a.m.
To: 'Robert Wilton'; '[email protected]'
Subject: Re: [netmod] Query about augmenting module from submodule in
YANG 1.0
Hi Rob,
That would make it very hard to update existing 1.x YANG models to use new
features in YANG 2.x if they used submodules. Maybe that's something that no
one would ever consider doing anyway, or maybe YANG 1.1 already has similar
differences to 1.0? I had (perhaps naively) assumed that you could migrate a
namespace / model from YANG 1.0 to 2.0?
Regards,
William
-----Original Message-----
From: netmod [mailto:[email protected]] On Behalf Of Robert
Wilton
Sent: 21 August 2017 11:24
To: [email protected]
Subject: Re: [netmod] Query about augmenting module from submodule in
YANG 1.0
On 09/08/2017 16:13, Juergen Schoenwaelder wrote:
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.
I agree.
I've added
https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_netmo
d
-2Dwg_yang-2Dnext_issues_26&d=DwICAg&c=LFYZ-o9_HUMeMTSQicvjIg&r=p8kye
K
3u4ZYiaQ2ZPGqwkyXmQgBH6r5jpYiYWzhqJ48&m=l7c4IPL049A2bVVO14fyBMly211xU
6 1xSHgPlAT7owI&s=-kR4fUtXArQy0RwWb32DpT1bP4X_cNqt2zJVoC0JiX8&e=
Rob
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
_______________________________________________
netmod mailing list
[email protected]
https://urldefense.proofpoint.com/v2/url?u=https-3A__www.ietf.org_mai
l
man_listinfo_netmod&d=DwICAg&c=LFYZ-o9_HUMeMTSQicvjIg&r=p8kyeK3u4ZYia
Q
2ZPGqwkyXmQgBH6r5jpYiYWzhqJ48&m=l7c4IPL049A2bVVO14fyBMly211xU61xSHgPl
A T7owI&s=t7vGIH8ABuAm00e-bkSowD9eawModGq0N2OkjANtpYI&e=
_______________________________________________
netmod mailing list
[email protected]
https://urldefense.proofpoint.com/v2/url?u=https-3A__www.ietf.org_mai
l
man_listinfo_netmod&d=DwIFAw&c=LFYZ-o9_HUMeMTSQicvjIg&r=p8kyeK3u4ZYia
Q
2ZPGqwkyXmQgBH6r5jpYiYWzhqJ48&m=esi8GPSc1xVjTt9SKxqzNHRDXT2P1h01a-Ueb
n ST-Yo&s=PctKy3ij6W0TQs1NFp18SX8MQtYKeG9RxADh3cphcxU&e=
_______________________________________________
netmod mailing list
[email protected]
https://urldefense.proofpoint.com/v2/url?u=https-3A__www.ietf.org_mai
l
man_listinfo_netmod&d=DwIBAg&c=LFYZ-o9_HUMeMTSQicvjIg&r=p8kyeK3u4ZYia
Q
2ZPGqwkyXmQgBH6r5jpYiYWzhqJ48&m=RH3zvD2B8_s4uw1PXm_ka37vgz9_q2Rc87tD8
K fZ9jA&s=XydU0vXE0AEg2FDE-kx_Ae6rOOAh5koxEeJ2cefgDNA&e=
_______________________________________________
netmod mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/netmod
