Chaining request data in Postman - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to extract the token from the first response.

Postman

var token = pm.response.json().[1];

Drag options to blanks, or click blank then click option'

Aaccess_token

Bheaders

Cstatus

Durl

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to access token from headers instead of JSON body.

Using incorrect key names like 'status' or 'url'.

The token is usually found in the JSON response body under the key access_token. Using pm.response.json().access_token extracts it correctly.

2fill in blank

medium

Complete the code to set the extracted token as an environment variable.

Postman

pm.environment.set('authToken', [1]);

Drag options to blanks, or click blank then click option'

Apm.response.headers.get('Authorization')

Btoken

Cpm.response.json().token

Dpm.request.body

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to set the environment variable directly from response without storing it first.

Using incorrect methods like accessing headers or request body.

After extracting the token into the variable token, you set it as an environment variable by passing the variable name directly.

3fill in blank

hard

Fix the error in the code to use the environment variable in the next request header.

Postman

pm.request.headers.add({ key: 'Authorization', value: 'Bearer ' + [1] });

Drag options to blanks, or click blank then click option'

Apm.environment.get('authToken')

B{{authToken}}

Ctoken

DauthToken

Attempts:

3 left

💡 Hint

Common Mistakes

Using {{authToken}} inside script strings, which doesn't get resolved.

Using plain variable names like 'authToken' without retrieval method.

In Postman pre-request scripts, retrieve the environment variable using pm.environment.get('authToken') and concatenate it to the Bearer prefix.

4fill in blank

hard

Fill both blanks to correctly extract user ID and set it as a global variable.

Postman

var userId = pm.response.json().[1];
pm.globals.set('[2]', userId);

Drag options to blanks, or click blank then click option'

Auser.id

Bid

CuserId

DuserID

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect key names like 'user.id' which is not valid syntax here.

Mismatching variable names between extraction and setting.

The user ID is typically under the key id inside the JSON response. Then, you set it as a global variable named userId for use in other requests.

5fill in blank

hard

Fill all three blanks to create a test that checks if the response status is 200 and the token exists.

Postman

pm.test('Status code is 200', function () {
    pm.response.to.have.status([1]);
});
pm.test('Token is present', function () {
    pm.expect(pm.response.json().[2]).to.exist;
    pm.environment.set('token', pm.response.json().[3]);
});

Drag options to blanks, or click blank then click option'

Aaccess_token

B200

Dtoken

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong status codes like 201 or 400.

Mismatching token key names in the test and environment set.

The first test checks if the status code is 200. The second test verifies that the access_token exists in the response JSON and sets it as an environment variable.

Practice

1. What is the main purpose of chaining request data in Postman?

easy

A. To pass data from one API request to another for connected testing

B. To run multiple requests at the same time

C. To change the request method automatically

D. To generate random data for each request

Solution

1. Step 1: Understand chaining request data

   Chaining request data means using data from one API response in the next request to keep tests connected.

2. Step 2: Identify the purpose

   This helps simulate real user flows where one action depends on the previous one.

3. Final Answer:

   To pass data from one API request to another for connected testing -> Option A

4. Quick Check:

   Chaining = passing data between requests [OK]

Hint: Chaining means passing data forward between requests [OK]

Common Mistakes:

• Thinking chaining runs requests simultaneously
• Confusing chaining with changing HTTP methods
• Assuming chaining generates random data

2. Which Postman script correctly saves a value from a JSON response to an environment variable named userId?

easy

A. pm.response.set('userId', pm.environment.json().id);

B. pm.environment.get('userId', pm.response.json().id);

C. pm.response.get('userId', pm.environment.json().id);

D. pm.environment.set('userId', pm.response.json().id);

Solution

1. Step 1: Identify correct method to save variable

   Use pm.environment.set(key, value) to save data to environment variables.

2. Step 2: Extract value from response JSON

   Use pm.response.json() to parse JSON and get the id field.

3. Final Answer:

   pm.environment.set('userId', pm.response.json().id); -> Option D

4. Quick Check:

   Set environment variable = pm.environment.set [OK]

Hint: Use pm.environment.set to save data from pm.response.json() [OK]

Common Mistakes:

• Using pm.environment.get to set a variable
• Confusing pm.response and pm.environment methods
• Trying to get data from environment instead of response

3. Given this Postman test script after a request:

const jsonData = pm.response.json();
pm.environment.set('token', jsonData.auth.token);

What will be the value of the environment variable token if the response JSON is {"auth": {"token": "abc123"}}?

medium

A. null

B. undefined

C. "abc123"

D. Error: token not found

Solution

1. Step 1: Parse the response JSON

   The response JSON has an object with auth containing token with value "abc123".

2. Step 2: Set environment variable

   The script sets token variable to jsonData.auth.token, which is "abc123".

3. Final Answer:

   "abc123" -> Option C

4. Quick Check:

   token value = "abc123" [OK]

Hint: Check JSON path matches response structure exactly [OK]

Common Mistakes:

• Assuming token is undefined if nested
• Forgetting to parse JSON before accessing
• Expecting error when token exists

4. You wrote this script to chain data:

const data = pm.response.json();
pm.environment.set('userId', data.user.id);

But the environment variable userId is always empty after the request. What is the likely problem?

medium

A. The script must run before the request

B. The response JSON does not have a user object

C. You must use pm.variables.set instead

D. pm.environment.set cannot save variables

Solution

1. Step 1: Check JSON structure

   If data.user is undefined, accessing data.user.id returns undefined, so variable is empty.

2. Step 2: Confirm environment.set works correctly

   pm.environment.set works if given a valid value, so problem is likely missing user in response.

3. Final Answer:

   The response JSON does not have a user object -> Option B

4. Quick Check:

   Missing JSON key = empty variable [OK]

Hint: Verify JSON keys exist before accessing nested values [OK]

Common Mistakes:

• Assuming pm.environment.set is broken
• Using wrong method like pm.variables.set
• Running script before response is received

5. You want to chain two requests where the first returns a list of users:

{"users": [{"id": 1}, {"id": 2}]}

You want to save the id of the first user to an environment variable firstUserId and use it in the second request URL as /users/{{firstUserId}}. Which script correctly does this in the first request's Tests tab?

hard

A. const jsonData = pm.response.json();
pm.environment.set('firstUserId', jsonData.users[0].id);

B. const jsonData = pm.response.json();
pm.environment.set('firstUserId', jsonData.users.id[0]);

C. const jsonData = pm.response.json();
pm.environment.set('firstUserId', jsonData.users[1].id);

D. const jsonData = pm.response.json();
pm.environment.set('firstUserId', jsonData.user[0].id);

Solution

1. Step 1: Parse response JSON correctly

   The response has a users array with objects containing id. The first user is at index 0.

2. Step 2: Save first user's id properly

   Access jsonData.users[0].id and save it with pm.environment.set.

3. Final Answer:

   const jsonData = pm.response.json(); pm.environment.set('firstUserId', jsonData.users[0].id); -> Option A

4. Quick Check:

   Array index 0 for first user id [OK]

Hint: Use array index [0] to get first item in JSON array [OK]

Common Mistakes:

• Using wrong array index or property name
• Accessing id as users.id[0] instead of users[0].id
• Using singular 'user' instead of 'users'