Steffen,
I'll make a sketch here, let me know if you have questions.
One ("maximum groupings") way of dealing with this would be:
module A {
grouping a-base-plate { ... }
}
module B {
import A { prefix a; }
grouping b-secret-sauce { ... }
grouping b-mounted-in-a {
uses a:a-base-plate {
augment grafting-point-in-base {
uses b-secret-sauce;
}
}
}
}
module C {
import A { prefix a; }
groping c-cool-stuff { ... }
grouping c-mounted-in-a {
uses a:a-base-plate {
augment grafting-point-in-base {
uses c-cool-stuff;
}
}
}
}
module D {
import A { prefix a; }
import B { prefix b; }
import C { prefix c; }
grouping d-full-echilada {
uses a:a-base-plate {
augment grafting-point-in-base {
uses b:b-secret-sauce;
}
augment grafting-point-in-base {
uses c:c-cool-stuff;
}
}
}
}
The same structure could also be built without groupings, just using augment,
but as I understand it, the point here was to build some rc:yang-data
structures, and then I guess the grouping approach is the way. The
"X-mounted-in-a" groupings could be skipped entirely if nobody is interested in
using B or C directly in a pre-packaged form.
Best Regards,
/jan
> Hi Jan,
>
> Thank you for the test.
>
>
> From: Anima <[email protected] <mailto:[email protected]>> On
> Behalf Of Jan Lindblad
> Sent: Donnerstag, 4. August 2022 12:23
> To: Michael Richardson <[email protected] <mailto:[email protected]>>
> Cc: [email protected] <mailto:[email protected]>; [email protected]
> <mailto:[email protected]>
> Subject: Re: [Anima] [netmod] mcr's YANG question raised during the ANIMA WG
> session
>
> Michael,
>
> I had a look at your test example. The example is invalid, but pyang fails to
> detect the error and overwrites some internal structures, with the result
> below. The root cause of the problem is this:
>
> module ietf-voucher-D {
> ...
> uses b:voucher-request-prm-grouping {
> augment "voucher" { }
> }
>
> uses c:voucher-request-constrained-grouping {
> augment "voucher" { }
> }
> }
>
> Each one of the two uses statement brings in a "container voucher" (with
> partly different content) at this point in the schema. That is an attempt at
> a duplicate definition of voucher, which is an error. Pyang misses this, and
> overwrites one voucher object with the next, losing some of the content.
>
> By placing the two uses statements into separate containers, pyang is able to
> successfully make a tree:
>
> module: ietf-voucher-D
> +--rw x1
> | +--rw voucher
> | +--rw created-on? yang:date-and-time
> | +--rw expires-on? yang:date-and-time
> | +--rw assertion? enumeration
> | +--rw serial-number string
> | +--rw idevid-issuer? binary
> | +--rw pinned-domain-cert? binary
> | +--rw domain-cert-revocation-checks? boolean
> | +--rw nonce? binary
> | +--rw last-renewal-date? yang:date-and-time
> | +--rw prior-signed-voucher-request? binary
> | +--rw proximity-registrar-cert? binary
> | +--rw agent-signed-data? binary
> | +--rw agent-provided-proximity-registrar-cert? binary
> | +--rw agent-sign-cert* binary
> +--rw x2
> +--rw voucher
> +--rw created-on? yang:date-and-time
> +--rw expires-on? yang:date-and-time
> +--rw assertion enumeration
> +--rw serial-number string
> +--rw idevid-issuer? binary
> +--rw pinned-domain-cert? binary
> +--rw domain-cert-revocation-checks? boolean
> +--rw nonce? binary
> +--rw last-renewal-date? yang:date-and-time
> +--rw proximity-registrar-pubk? binary
> +--rw proximity-registrar-pubk-sha256? binary
> +--rw proximity-registrar-cert? binary
> +--rw prior-signed-voucher-request? binary
>
> Normally in YANG, it wouldn't be hard to to let modules "B" and "C" augment
> module "A" independently. But here you are working with groupings in such a
> way that both "B" and "C" build up a complete grouping with everything in
> "A". When "D" tries to use both "B" and "C", there is inevitably unwanted
> duplication. If instead, "B" and "C" just defined their little contributions,
> "D" could import groupings from "A", "B" and "C" and compose them as desired.
>
> [stf] Just to be sure, you said you would recommend to avoid the “use”
> statement, which leads to duplication when creating “D”. I understand this
> for the inclusion case.
> If we use voucher B stand alone without the “use” statement wouldn’t we miss
> a part of the voucher? Or would you recommend to move the use out of the
> grouping?
>
> Regards
> Steffen
>
>
> Best Regards,
> /jan
>
_______________________________________________
Anima mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/anima
