Size of JSON array

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1

Hi.

I have calls that return me an xml. To navigate the response, I first convert it to JSON with the following:

var jsonObject = xml2Json(responseBody);

I then address its parts with variables hierarchically like this:

var x = jsonObject[‘x’]
var y = x[‘y’]

My goal is to use the test script to figure out how many elements the x-array has, i.e. how many y-blobs there are (how many y children of the main x object).

I tried with

x.length

and the previous definition of x, but in this case I get null.

Can anyone help? Thanks!!!

2

Would you mind providing an example of what your xml/json looks like please?

3

I do not know how to post xml here…

4

image

5

Looking at the XML picture you provided,
you’ll be getting a JSON as:

 x = [
  "y1",
  "y2"
]

If you just write x.length, you’ll actually get the number of items there are there in the x array.

var x = jsonObject[‘x’],
  numberOfYItems = x.length;

Is that what you were trying to achieve?

6

It is, but I get null. I will try to provide a more realistic example (I have to change label names and so on).

7

Ohh, there could be some other issue.
Array.length can never give you null, if it’s not an array but an object then it will give you an undefined.

I think the x is actually an object here which already has a property length with a value null

Can you write console.log(x, Array.isArray(x)); and open Postman console and show the result after you send the request?
Feel free to retract any sensitive information.

8

The command you are using to convert to json is just converting the xml to a json string.

Take a look at this javascript I wrote to test.

I think you’re just missing JSON.parse

2 Likes
9

Ok, the trouble seems to come from the XML, which is a bit strange. I will have to investigate it. Your example works fine.

10

This is now working:

var jsonObject = xml2Json(responseBody);

let hasMemberArray = jsonObject[‘PizzaMessage’][‘hasMember’]
pm.test(“response contains exactly three hasMember entries”, function () {
pm.expect(hasMemberArray.length).to.equal(3);
});

I was probably doung something really stupid. Thanks, everyone!!!

1 Like