How to match dynamic key in nested json object in karate?

Question

Trying to match nested json object from API response in Karate framework. Following in my API response.

    "status": {
        "code": 0,
        "message": "Successful"
    },
    "data": {
        "PHX": {
            "name": "Phoenix (All)",
            "city_code": "PHX",
            "country_code": "US",
            "country_name": "United States",
            "city_name": "Phoenix",
            "type": "city",
            "airports": {
                "SCF": {
                    "name": "Scottsdale Municipalcipal",
                    "city_code": "PHX",
                    "city_name": "Phoenix",
                    "country_code": "US",
                    "country_name": "United States",
                    "lat": 33.61667,
                    "lng": -111.916664,
                    "timezone": "America/Phoenix",
                    "type": "airport"
                },
                "PHX": {
                    "name": "Sky Harbor International",
                    "city_code": "PHX",
                    "city_name": "Phoenix",
                    "country_code": "US",
                    "country_name": "United States",
                    "lat": 33.435036,
                    "lng": -112.00016,
                    "timezone": "America/Phoenix",
                    "type": "airport"
                },
                "AZA": {
                    "name": "Williams Gateway",
                    "city_code": "PHX",
                    "city_name": "Phoenix",
                    "country_code": "US",
                    "country_name": "United States",
                    "lat": 33.307777,
                    "lng": -111.655556,
                    "timezone": "America/Phoenix",
                    "type": "airport"
                },
                "DVT": {
                    "name": "Phoenix Deer Valley Airport",
                    "city_code": "PHX",
                    "city_name": "Phoenix",
                    "country_code": "US",
                    "country_name": "United States",
                    "lat": 33.683887,
                    "lng": -112.083336,
                    "timezone": "America/Phoenix",
                    "type": "airport"
                },
                "LUF": {
                    "name": "Luke AFB",
                    "city_code": "PHX",
                    "city_name": "Phoenix",
                    "country_code": "US",
                    "country_name": "United States",
                    "lat": 33.61667,
                    "lng": -111.916664,
                    "timezone": "America/Phoenix",
                    "type": "airport"
                }
            }
        }
    }
}

I'm trying to match json object in data, here very tricky part is key "PHX" will be dynamic and I may get as many as json nested objects. Also the airports nested json like "SCF", "PHX", "AZA" are also dynamic. How can I write match statement in Karate? Tried several answers for dynamic keys but my API response is quite different here.

I'm tried below changes in feature file:

 * def response_data_airports =  { "#string": { "name": "#string", "city_code": "#string", "city_name": "#string", "country_code": "#string", "country_name": "#string", "lat": "#number", "lng": "#number", "timezone": "#string", "type": "#string" }}
 * def main_schema = { '#string': { "name": "#string", "city_code":
   "#string", "country_code": "#string", "country_name": "#string",
   "city_name": "#string", "type": "#string", "airports":
   '#(^response_data_airports)' }  }
 * match flightAutocompleteDetails.response.data contains main_schema

Thank you

I referred answers from @peter-thomas for solving dynamic keys but my case is quite different. — Veerabbhadrayya Math, Aug 16 '23 at 10:25
what are you trying to match ? you have not made that clear at all. — Peter Thomas, Aug 16 '23 at 10:32
I'm trying to match API response from `data` json nested object values, edited my question. Thank you — Veerabbhadrayya Math, Aug 16 '23 at 10:37
that honestly does not help at all. anyway I will try my luck, take it or leave it — Peter Thomas, Aug 16 '23 at 10:40
Here I'm trying to validate JSON schema with values inside `data` nested objects like `PHX` . And `airports` will have several nested objects. Hope I'm clear now. — Veerabbhadrayya Math, Aug 16 '23 at 10:43

Peter Thomas · Accepted Answer · 2023-08-23T12:06:24.437

Yes, this JSON is not easy to tackle. So you have to do a transform. I am focusing only on the response.data.PHX.airports part, the rest is a home-work for you ;)

* def data = []
* karate.forEach(response.data.PHX.airports, (k, v) => { v.code = k; data.push(v) })

EDIT: since you weren't happy with my first answer, here is how you can avoid hard-coding PHX, and I can give you hints, you have to do what is right for your situation. Read other examples, there are many ways to "unpack" keys:

* def data = []
* def code = karate.keysOf(response.data)[0]
* karate.forEach(response.data[code].airports, (k, v) => { v.code = k; data.push(v) })

If you need more help to understand this, refer: https://github.com/karatelabs/karate#json-transforms

What this does is gives you a neat array and also takes the key and adds it to each array item as a code property. Now you can easily do all the Karate matches you want.

* match data[*].code == ['SCF', 'PHX', 'AZA', 'DVT', 'LUF']

And since you seem to be stressing over doing a "schema" match, sure:

* match each data contains { name: '#string', city_code: '#string' }

My advice for testing is always test the whole payload, even if it feels like you are "hard coding" data. That is more useful to test whether your system is working correctly (instead of just schema matching) in my honest opinion.

Also see: https://stackoverflow.com/a/57929311/143475

Thank you @peter-thomas for your valuable time, but airports json object may change and data.`airport_code` could also change. below is another example. `"data": {"LAX": {"name": "Los Angeles (All)","city_code": "LAX","country_code": "US","country_name": "United States","city_name": "Los Angeles","type": "city","airports": {"WHP": {"name": "Whiteman","city_code": "LAX","city_name": "Los Angeles","country_code": "US","country_name": "United States","lat": 34.05,"lng": -118.25,"timezone": "America/Los_Angeles","type": "airport"}}} ` — Veerabbhadrayya Math, Aug 16 '23 at 11:03
@VeerabbhadrayyaMath yes I know that. I don't think you have understood my answer. did you try it for `LAX` ? `name` and `city_code` are still the same, right ? I am also saying that when you make a request and expect `LAX` back, just hard code a JSON in your test and do a match. that is the best kind of test in my opinion, instead of struggling to do `#string` kind of matches. if the solution given does not help, please look for another framework. or you can let me know how to solve your question in some other framework. anyway I am editing my answer for all "general" cases — Peter Thomas, Aug 16 '23 at 12:40

How to match dynamic key in nested json object in karate?

1 Answers1