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Verify GET API returns correct user data

Preconditions (2)

Step 1: Send a GET request to https://api.example.com/users/123

Step 2: Check the response status code is 200

Step 3: Verify the response body contains user ID 123

Step 4: Verify the response body contains user name 'John Doe'

Step 5: Verify the response body contains email '[e-mail]'

✅ Expected Result: The API returns status 200 and the correct user data in JSON format

Automation Requirements - Postman

Assertions Needed:

Status code is 200

Response JSON contains correct user ID

Response JSON contains correct user name

Response JSON contains correct email

Best Practices:

Use environment variables for API base URL

Use test scripts in Postman to assert response data

Keep tests independent and repeatable

Validate both status code and response body content

Automated Solution

Postman

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

const responseJson = pm.response.json();
pm.test('User ID is 123', function () {
    pm.expect(responseJson.id).to.eql(123);
});

pm.test('User name is John Doe', function () {
    pm.expect(responseJson.name).to.eql('John Doe');
});

pm.test('User email is [e-mail]', function () {
    pm.expect(responseJson.email).to.eql('[e-mail]');
});

This Postman test script checks the API response after sending a GET request.

First, it verifies the status code is 200, meaning the request succeeded.

Then, it parses the JSON response and checks that the user ID, name, and email match the expected values.

Using pm.test and pm.expect ensures clear, readable assertions that will show pass or fail in the Postman test results.

This approach helps confirm the API returns correct data and is working as expected.

Common Mistakes - 3 Pitfalls

Not checking the status code before validating response data

Hardcoding API URLs directly in tests

Not parsing JSON response before accessing fields

Bonus Challenge

Now add data-driven testing with 3 different user IDs and verify their data

Show Hint