How to validate POST request body required params in Pre-request script?

Question

I have few need-to-have params in JSON raw data in my request body and I want to validate in the pre-request script in Postman if those params are present in the body or not.

{
  "stores": [
    {
      "city": "Tokyo",
      "name": "Church Street"
      ....
      ....
    }
  ]
}

How to check if city and name is passed or not in the request body?

score 1 · Accepted Answer · answered Apr 07 '20 at 08:12

You can use the pm.test function with the pm.expect assertions in the Pre-request Scripts.

As Postman comes with Lodash, you can use the _.get() function in the sandbox to get the data from the stores array. You would need to use JSON.parse() to correctly assign the data from the request body in the _.get() function.

let requestBody = _.get(JSON.parse(pm.request.body.raw), 'stores[0]')

pm.test("Check Body", () => {
    pm.expect(requestBody).to.have.keys(['city', 'name'])
})

Or something like this without Lodash:

let requestBody = JSON.parse(pm.request.body.raw)

pm.test("Check Body", () => {
    pm.expect(requestBody.stores[0]).to.have.keys(['city', 'name'])
})

More info on the pm.* API can be found here:

https://learning.postman.com/docs/postman/scripts/postman-sandbox-api-reference/

Thank you @DannyDainton I can now able to validate the results successfully. — Pruthvi K R, Apr 08 '20 at 11:16

score 0 · Answer 2 · answered Apr 07 '20 at 07:39

Use pm.test as you can see request body, content-type, response content in Run Results. Export Results has too many details.

Test Request Body:

pm.test(JSON.parse(pm.request.body));

Test URLEncoded with Request Body:

pm.test(JSON.stringify(pm.request.body.urlencoded.toObject(true)));

Test Raw Text in Request Body:

 pm.test(JSON.parse(pm.request.body.raw));

Example:

var reqBody = request.data; //JSON.parse(request.data);
tests["Data"] = reqBody.stores[0].city !== null;

How to validate POST request body required params in Pre-request script?

2 Answers2