Using Chai assertion library in Postman - Test Execution Trace

Test Overview

This test sends a GET request to a sample API endpoint and uses the Chai assertion library to verify that the response status is 200 and the response body contains a specific property.

Test Code - Postman with Chai assertions

Postman

pm.test("Status code is 200", function () {
    pm.response.to.have.status(200);
});

pm.test("Response has userId property", function () {
    const jsonData = pm.response.json();
    pm.expect(jsonData).to.have.property('userId');
});

Execution Trace - 3 Steps

Step	Action	System State	Assertion	Result
1	Send GET request to https://jsonplaceholder.typicode.com/posts/1	Request sent, waiting for response	-	PASS
2	Check response status code using pm.response.to.have.status(200)	Response received with status 200	Verify status code is 200	PASS
3	Parse response JSON and check if it has property 'userId' using pm.expect	Response body parsed as JSON: { userId: 1, id: 1, title: "...", body: "..." }	Verify response JSON has property 'userId'	PASS

Failure Scenario

Failing Condition: Response status is not 200 or response JSON does not have 'userId' property

Execution Trace Quiz - 3 Questions

What does the first assertion check in this test?

A That the request URL is correct

B That the response body contains 'userId'

C That the response status code is 200

D That the response time is less than 200ms

Key Result

Always verify both the HTTP status code and the expected properties in the response body to ensure the API behaves correctly.