Generate xml/json from Yang model

Question

I've been trying to find something that can generate sample xml/json data from the yang model in java, For eg for xsd there are tools where you can generate the Sample xml.

I tried Pyang: 1. Its in Python. 2. After conversion it gives me yin format which is xml equivalent of yang specs. for Eg. for following yang code if I convert it to YIN using pyang:

 leaf templateSendPeriod {
      when "../exportProtocol!='netflow-v5'";
      type uint16;
      default 60;
      units seconds;
    }

This is what I got-

 <leaf name="templateSendPeriod">
      <when condition="../exportProtocol!='netflow-v5'"/>
      <type name="uint16"/>
      <default value="60"/>
      <units name="seconds"/>
    </leaf>

Instead what I wanted was

<templateSendPeriod></templateSendPeriod>

So that I could get the xml, enter the details and validate against the same yang.

Answer 1

You can do this way, First declare your model

// module name
module napalm-star-wars {

    // boilerplate
    yang-version "1";
    namespace "https://napalm-yang.readthedocs.io/napalm-star-wars";

    prefix "napalm-star-wars";

    // identity to unequivocally identify the faction an individual belongs to
    identity AFFILIATION {
      description "To which group someone belongs to";
    }

    identity EMPIRE {
      base AFFILIATION;
      description "Affiliated to the empire";
    }

    identity REBEL_ALLIANCE {
      base AFFILIATION;
      description "Affiliated to the rebel alliance";
    }

    // new type to enforce correctness of the data
    typedef age {
      type uint16 {
        range 1..2000;
      }
    }

    // this grouping will all the personal data we will assign to individuals
    grouping personal-data {
        leaf name {
            type string;
        }
        leaf age {
            type age;
        }
        leaf affiliation {
            type identityref {
                base napalm-star-wars:AFFILIATION;
            }
        }
    }

    // this is the root object defined by the model
    container universe {
        list individual {
            // identify each individual by using the name as key
            key "name";

            // each individual will have the elements defined in the grouping
            uses personal-data;
        }
    }
}

Do tree representation of your model

$ pyang -f tree napalm-star-wars.yang
module: napalm-star-wars
    +--rw roster
        +--rw individual* [name]
           +--rw name           string
           +--rw age?           age
           +--rw affiliation?   identityref

later use this in your python code:

>>> import napalm_star_wars
>>>
>>> sw = napalm_star_wars.napalm_star_wars()
>>>
>>> obi = sw.universe.individual.add("Obi-Wan Kenobi")
>>> obi.affiliation = "REBEL_ALLIANCE"
>>> obi.age = 57
>>>
>>> luke = sw.universe.individual.add("Luke Skywalker")
>>> luke.affiliation = "REBEL_ALLIANCE"
>>> luke.age = 19 

Here you get the answer for getting json or xml as per your choice..

import json
>>> print(json.dumps(sw.get(), indent=4))