Postman - re-use same request for testing?

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1

In Postman you can define multiple response examples.

200 > success
404 > not found

In the postman collection, the examples are added but I cannot execute the request in Postman to return a 404.

I want to be able to run a request 2 times:

  • happy path: run the request and test if the path returns a 200
  • unhappy path: run the same request, but for example use a blank request parameter and test for a 404

Is there a way to do this natively in Postman?
Or is the only option to duplicate the request and manually modify the request to make the parameter blanc and test for a 404?

2

Hi @thim! I’m not sure if I’m fully understanding your question, but here’s a method that may be helpful for you:

removeQueryParams allows you to programmatically remove a query param from a search. You can add in some conditional logic in your Pre-request script to determine whether or not to include a query parameter.

3

You may want to look into data-driven testing.

Essentially, you reuse the same request but use a different data set for each execution. The external data file needs to be in CSV or JSON.

Here is a tutorial that can help you get started:

You can define expected data in your external fine and use that in your assertions.

Something like:

pm.test("Status code", () => {
    pm.response.to.have.status(pm.variables.get('expectedStatusCode'));
});
4

I’m looking more for a different flow

Execute a request > validate for 200 response
Next remove a paramater from the same request > Execute the same request > validate for 404 response.

I’m not sure how the data-driven flow via a CSV/JSON file would facilitate this?

5

Hello @thim, If I get your requirement correctly,

You need to test a same request for positive and negative flows (test case should pass though).

You can try a simple if else statement with the response Codes. Also I believe you are trying to do get 404 by removing the params. In that case,

Step 1: Make sure to parameterize the parameters of the request.
Step 2: Under your tests section you can write a if else logic like below:

if (pm.response.code === 200)
{    pm.test("Status code is 200", function () {
        pm.response.to.have.status(200);
        pm.environment.set("pathparam1","dummy");
    });
    }
else if (pm.response.code === 404){
pm.test("Status code is 404", function () {
    pm.response.to.have.status(404);
    pm.environment.set("pathparam1","pet");
    }); 
}

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You can customize it based on your needs :blush:

1 Like
6

@bpricilla I think I understand properly.

How do you rerun the same request? Would this be done by the newman iterations option?
And how do you know when to stop rerunning the samen request?

7

Hi @thim, I just clicked send twice. Since you said single request for validating two response codes. Based on your need you can tweak it :blush: It’s a rough idea based on my logic :slight_smile:

How are you running the remaining requests? And what’s the business usage for validating the same request for two different response codes?

8

@thim if you want to run requests in a collection in a specific order (or in your case, rerun the same request based on some status code conditions), you can do so using the postman.setNextRequest() method. Here’s a helpful resource on building workflows.