AssertionError to check keys in json

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1

I have an API Endpoint that returns a JSON array in response:

[
    {
        "base": "ethereum-eth",
        "quote": "tether-usdt",
        "volume": 60126390.25608005,
        "price": 1663.0597462528697,
        "volumePercent": 32.36999258988893,
        "spread": 0.006014675808968427,
        "category": "Verified",
        "time": 1659695310
    },
]

I try to run the code below for each item of Array

pm.test("Check if response contains all the keys", function () {
    var data = pm.response.json();
    data.forEach(function(item) {
        pm.expect(item).to.have.all.keys('base', 'qoute', 'volume', 'price', 'volumePercent', 'spread', 'category', 'time');     
    });
});

Response

Check if response contains all the keys | AssertionError: expected { base: 'ethereum-eth', …(7) } to have keys 'base', 'qoute', 'volume', 'price', 'volumePercent', 'spread', 'category', and 'time'

For some reason, even for one item, I have an Assertion error

pm.test("Check if response contains all the keys", function () {
    var data = pm.response.json();
    console.log(data[0]);
    pm.expect(data[0]).to.have.all.keys('base', 'qoute', 'volume', 'price', 'volumePercent', 'spread', 'category', 'time');
});

How I can resolve it? pls, help

2

Hi @science-pilot-863855

The easiest way to achieve this is to have multiple assertions, like this;

const response = pm.response.json();

pm.test("Check if response contains all the keys", function () {
    pm.expect(response).to.have.property('base');
    pm.expect(response).to.have.property('quote');
    pm.expect(response).to.have.property('volume');
    pm.expect(response).to.have.property('price');
    pm.expect(response).to.have.property('volumePercent');
    pm.expect(response).to.have.property('spread');
    pm.expect(response).to.have.property('category');
    pm.expect(response).to.have.property('time');
})

However, if it is necessary to run a for loop, then you could do this;

const response = pm.response.json();

//get all of the keys from the response as an array
let arrayOfResponseKeys = Object.keys(response);
console.log(arrayOfResponseKeys);

//create an array with what you expect the keys to be
let myKeysList = ['base', 'quote', 'volume', 'price', 'volumePercent', 'spread', 'category', 'time'];
console.log(myKeysList);

pm.test("Check if response contains all the keys with for loop", function () {
    //loop through the response array
    for (let x = 0; x < response.length; x++) {
        //for each item in the response array, loop through the entire array of keys
        for (let y = 0; y < myKeysList.length; y++) {
            //match the response array to the expected array
            pm.expect(arrayOfResponseKeys[y]).to.include(myKeysList[y]);
        }
    }
})

Note: you also had a spelling mistake that threw me off a little, your second key was spelt ‘qoute’. Thought it was worth mentioning just in case it caused any further issues.

3

Thanks, I thought about some spelling mistakes and I checked everything a few times. lol, it was so simple.
And also thank you for advice, I found a validation schema that is also easy to use: https://postman-quick-reference-guide.readthedocs.io/en/latest/schema-validation.html#object-has-required-property

4

Shouldn’t these be multiple tests, rather than multiple assertions in the same test.

If the first assertion fails, then the rest of the assertions\tests don’t run. Therefore if multiple properties are missing, you aren’t necessarily going to see that in the results, making troubleshooting the issue more difficult.

5

If you use try/catch inside the test it would go through all of the properties regardless of failures. The result would be a full list of passed and failed assertions inside a singular test.

Better yet, use schema validation.

6

I was going to say that, to use the schema validation as shown in the learning\training modules.