Re: [netmod] WGLC - draft-ietf-netmod-yang-tree-diagrams

[Vladimir Vassilev <[e-mail]>]

Hi,

I have reviewed and implemented (apart from schema mount specific 
functionality) draft-ietfetf-netmod-yang-tree-diagrams-04 and found the 
following issues:

==sec 2.6.  Node Representation==

1. To correctly reflect the current pyang output one needs to add '--' 
between <status> and <flags>.
OLD:
     <status> <flags> <name> <opts> <type> <if-features>
NEW:
     <status>--<flags> <name> <opts> <type> <if-features>

There is also undocumented alignment space count function before <type> 
that pyang uses to align the <type> fields of child data leafs with 
common ancestor. If this is specified in the draft the tree output can 
be deterministic and for me this is an advantage. This is currently one 
of the few underspecified pieces of the tree format so I had to check 
pyang implementation in oder to generate same alignment space counts and 
binary identical tree output results.


2. It is unclear which <flags> option should be used for rpc and action 
input/output and child nodes and the notification child nodes. pyang 
uses '-w' for input and input/* and 'ro' for output and output/*:

     module: ietf-netconf-partial-lock
       rpcs:
         +---x partial-lock
         |  +---w input
         |  |  +---w select*   string
     ...

pyang also uses '--' as <flags> for augmentation data nodes for actions 
input.

     ...
       augment /rt:routing-state/rt:ribs/rt:rib/rt:active-route/rt:input:
         +---- destination-address?   inet:ipv4-address
     ...


3. pyang is prefixing choice node names with the parent <flags> e.g. 
+--ro (next-hop-options) while case nodes are not prefixed. I guess this 
is a bug in pyang since it is not specified in the draft but choice 
nodes prefixed with parent <flags> are  also present in the sec 4 and 
4.1 examples?

4. This bit I found confusing. I propose this change to unambiguously 
describe the current pyang format.

OLD:
          *  for a leaf-list or list
          [<keys>] for a list's keys
NEW:
          *  for a leaf-list or list without keys
          * [<keys>] for a list with keys

Vladimir

On 01/01/2018 11:01 PM, joel jaeggli wrote:
> Greetings,
>
> We hope  the new year is a time to make great progess on outstanding
> documents before preparation for the  London IETF begins in earnest.
>
> This starts a two-week working group last call on:
>
>   YANG Tree Diagrams
> draft-ietf-netmod-yang-tree-diagrams
>
> https://datatracker.ietf.org/doc/draft-ietf-netmod-yang-tree-diagrams/
>
> Please send email to the list indicating your support or concerns.
>
> We are particularly interested in statements of the form:
>
>    * I have reviewed this draft and found no issues.
>    * I have reviewed this draft and found the following issues: ...
>
>
> Thank you,
> NETMOD WG Chairs