Re: [netconf] Usage examples for max-depth (rfc8526)

[Balázs Lengyel <[e-mail]>]

As a private opinion:

Providing a list without keys is kind of useless. IMHO keys should 
always be present if the list is allowed by depth. In my view the 
correct answer is:

Example 3: no subtree filter is provided, max-depth=3
        <top xmlns="http://example.com/schema/1.2/config">
          <users>
            <user>
               <name>Joe</name>
            </user>
            <user>
               <name>Bill</name>
            </user>
            <user>
               <name>Balazs</name>
            </user>
          </users>
        </top>

So even if the key name is strictly speaking on depth=4 it should be 
included in a level 3 get result.

regards Balazs

On 2019. 03. 14. 9:53, Wisotzky, Sven (Nokia - DE/Stuttgart) wrote:
> Unfortunately the info provided in RFC 8526 about the max-depth attribute is not very precise.
> Is it fair to assume, that behavior is aligned with the RESTCONF "depth" attribute described in RFC 8040?
>
> Let's use the following sample from chapter 3.1.1.3:
>         <top xmlns="http://example.com/schema/1.2/config">
>           <users>
>             <user>
>               <name>root</name>
>               <type>superuser</type>
>               <full-name>Charlie Root</full-name>
>               <company-info>
>                 <dept>1</dept>
>                 <id>1</id>
>               </company-info>
>             </user>
>             <!-- additional <user> elements appear here... -->
>           </users>
>         </top>
>
> Example 1: no subtree filter is provided, max-depth=1
>         <top xmlns="http://example.com/schema/1.2/config">
>         </top>
>
> Example 2: no subtree filter is provided, max-depth=2
>         <top xmlns="http://example.com/schema/1.2/config">
>           <users>
>           </users>
>         </top>
> Assumption the container <users> would only be present in the result, if this container has any explicit children configuration. If there is no children config, it would not be part of the output.
>
> Example 3: no subtree filter is provided, max-depth=3
>         <top xmlns="http://example.com/schema/1.2/config">
>           <users>
>             <user>
>             </user>
>           </users>
>         </top>
> Somewhat interesting scenario. It provides the netconf client with a method to check, if a list contains any entries. So if the XML node <user> is contained, we would know that the list "user" has at least one entry. However, this XML output would not validate against the YANG model - because list-keys (user/name) are mandatory. In essence, that client requires to be flexible when parsing such result and cannot be restricted to YANG.
>
> Example 4: no subtree filter is provided, max-depth=4
>         <top xmlns="http://example.com/schema/1.2/config">
>           <users>
>             <user>
>               <name>root</name>
>               <type>superuser</type>
>               <full-name>Charlie Root</full-name>
>               <company-info>
>               </company-info>
>             </user>
>             <!-- additional <user> elements appear here... -->
>           </users>
>         </top>
> Similar to example 2, the container <company-info> would only be present, if this container has explicit children configuration.
>
>
> Someone please to confirm, if those examples and assumptions being made are correct!
>
> /wiso
>
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-- 
Balazs Lengyel                       Ericsson Hungary Ltd.
Senior Specialist
Mobile: [phone]              email: [e-mail]