[netconf] YANG Push patch messages

[Michal Vasko <[e-mail]>]

Hi,

I wanted to clarify how exactly should the YANG Patch messages look like 
when sending YANG Push on-change notifications. Specifically, it is not 
clear whether nested changes should be reported. Example:

YANG:
list l {
   key "k";
   leaf k {
     type string;
   }
   leaf x {
     type string;
   }
}

Data:
<l>
   <k>key</k>
   <x>value</x>
</l>

1) An instance of `l` with `x` is created. The patch can then report a 
single creation of `l` or a creation of `l` and `x`. Since the YANG 
Patch includes a value <https://www.rfc-editor.org/rfc/rfc8072#page-19> 
node, I assume it should be the former and only a single change reported 
because all the descendants are included in the `value` node.

2) An instance of `l` with `x` is deleted. Here it is a bit more tricky 
because deletions cannot include the `value` node because of its when 
condition. So, should all the nested deletions be reported individually 
or report only the parent change? Only a single deletion would be used 
for a similar RESTCONF edit but in this case the information about any 
deleted descendants would be lost, is that intentional or should the 
nested changes be also reported?

Regards,
Michal