Query on using instance-identifier yang type

[akumartm]

How can I use the "instance-identifier" type to reference an instance of a nested list within a YANG data model? For instance, consider a YANG module where there are two lists, "a" and "b", with "b" nested inside "a". Additionally, there is a leaf "c" within "a", and I want to utilize the "instance-identifier" type for leaf "c" to reference an instance of list "b".

Here is yang structure.
list a {
  key a-key;
  leaf a-key {
    type string;
  }
  list b {
    key b-key;
    leaf b-key {
      type string;
    }
  }
  leaf c {
    type instance-identifier;
  }
}

When I try to configure it from cli, it doesnt show up the instance of list b.
admin@ncs(config)# a test b btest
admin@ncs(config-b-btest)# exit
admin@ncs(config-a-test)# c /a[a-key=test]/b?
Possible completions:
b <cr>
admin@ncs(config-a-test)# c /a[a-key=test]/b
--------------------------------------^
syntax error: The XPath /a[a-key=test]/b doesn't belong to the restricted subset.


Any pointers on this.

[snovello]

You used the wrong key name and did not quote.
Here are examples of how NSO behaves when you correct ithe sytax
admin@ncs(config-a-test)# c /a[a-key='test']
admin@ncs(config-a-test)# c /test:a[test:a-key='test']
admin@ncs(config-a-test)# c /test:a[test:a-key='test']/test:b
----------------------------^
syntax error: /a/b: Invalid path
admin@ncs(config-a-test)# c /test:a[test:a-key='test']/test:b[test:b-key='btest']
admin@ncs(config-a-test)#

In https://datatracker.ietf.org/doc/html/rfc7950#section-9.13
It says that you also need the preifx everywhere, but NSO accepts an instance identifier without the module prefix.

As you see if the path is to a list rather than to a list-element NSO says the path is invalid (tested on version 6.2)

The RFC mentions the path has to reference a ‘particular instance node’ but I did not find a clear defintion of what that means. I assume it means that some nodes are not allowed otherwise it would have just said ‘node’ or ‘particular node’. The examples given in the RFC do not show an instance-identifier to a list.

[akumartm]

Hi, 
Okay, so are we supposed to give a valid input by manually typing the xpath?
Why dont we get it in tab completion?
If I try to use tab completion, It doesn't even show up the instance of nested list.