Variable syntax ({{variable}}) in Postman - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to correctly reference a variable in Postman.

Postman

pm.environment.set([1], '12345');

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

A'userId'

BuserId.value

C{{userId}}

DuserId

Attempts:

3 left

💡 Hint

Common Mistakes

Using {{userId}} directly without quotes causes syntax errors.

Using variable.value is incorrect for setting variables.

In Postman scripts, variable names must be passed as strings when setting environment variables.

2fill in blank

medium

Complete the code to retrieve a variable value using Postman variable syntax.

Postman

const token = pm.variables.get('[1]');

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

Atoken

Bpm.variables

CauthToken

D{{authToken}}

Attempts:

3 left

💡 Hint

Common Mistakes

Including curly braces inside the string causes the variable not to be found.

Passing the variable object instead of its name.

When retrieving a variable, pass the variable name as a string without curly braces.

3fill in blank

hard

Fix the error in the code to correctly use a variable in a request URL.

Postman

const url = `https://api.example.com/users/$[1]/details`;

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

Apm.variables.get('userId')

BuserId

C{{userId}}

D'userId'

Attempts:

3 left

💡 Hint

Common Mistakes

Using {{userId}} inside backticks does not get replaced automatically.

Using the variable name as a string does not insert the value.

Inside template literals, you must embed JavaScript expressions, not Postman variable syntax.

4fill in blank

hard

Fill both blanks to correctly set and then use a variable in Postman scripts.

Postman

pm.environment.set('[1]', '12345');
const id = pm.environment.get('[2]');

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

AsessionId

BuserId

DauthToken

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names causes undefined values.

Omitting quotes around variable names causes errors.

Use the same variable name when setting and getting to maintain consistency.

5fill in blank

hard

Fill all three blanks to create a dynamic request URL using Postman variables.

Postman

const baseUrl = pm.environment.get('[1]');
const user = pm.variables.get('[2]');
const fullUrl = `$[3]/users/${user}/profile`;

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

Abase_url

Busername

CbaseUrl

DuserId

Attempts:

3 left

💡 Hint

Common Mistakes

Using Postman variable syntax inside template literals instead of JavaScript variables.

Mismatching variable names between get() calls.

Retrieve variables by their names as strings, then use JavaScript variables inside template literals.

Practice

1. What is the correct way to use a variable named userId in a Postman request URL?

easy

A. Use $userId in the URL to insert the variable value.

B. Use [userId] in the URL to insert the variable value.

C. Use {{userId}} in the URL to insert the variable value.

D. Use userId directly without any special syntax.

Solution

1. Step 1: Understand Postman variable syntax

   Postman uses double curly braces {{variable}} to insert variable values dynamically.

2. Step 2: Apply syntax to the variable userId

   To use the variable userId, you write {{userId}} in the request URL or body.

3. Final Answer:

   Use {{userId}} in the URL to insert the variable value. -> Option C

4. Quick Check:

   Variable syntax = {{variable}} [OK]

Hint: Remember variables always use double curly braces {{}} [OK]

Common Mistakes:

• Using single brackets or dollar sign instead of {{}}
• Writing variable name without any braces
• Confusing variable syntax with other languages

2. Which of the following is the correct syntax to reference a variable named token in Postman?

easy

A. {token}

B. {{token}}

C. [[token]]

D. $token

Solution

1. Step 1: Recall Postman variable syntax rules

   Postman requires variables to be wrapped in double curly braces to be recognized.

2. Step 2: Match the correct syntax for variable token

   The correct syntax is {{token}}, which tells Postman to replace it with the variable's value.

3. Final Answer:

   {{token}} -> Option B

4. Quick Check:

   Variable reference = {{variable}} [OK]

Hint: Always use double curly braces {{}} for variables [OK]

Common Mistakes:

• Using single braces or brackets
• Using dollar sign prefix
• Forgetting braces entirely

3. Given the environment variable baseUrl is set to https://api.example.com, what will be the full URL when the request uses {{baseUrl}}/users?

medium

A. https://api.example.comusers

B. {{baseUrl}}/users

C. https://api.example.com{{baseUrl}}/users

D. https://api.example.com/users

Solution

1. Step 1: Understand variable substitution in Postman

   Postman replaces {{baseUrl}} with its set value before sending the request.

2. Step 2: Substitute {{baseUrl}} with its value

   Since baseUrl is https://api.example.com, the URL becomes https://api.example.com/users.

3. Final Answer:

   https://api.example.com/users -> Option D

4. Quick Check:

   Variable replaced URL = https://api.example.com/users [OK]

Hint: Variables replace exactly with their set values [OK]

Common Mistakes:

• Not replacing variable and leaving {{baseUrl}} as is
• Concatenating variable value incorrectly
• Missing slash between baseUrl and path

4. You wrote Authorization: Bearer {token} in the headers, but the token is not replaced. What is the error?

medium

A. Variable syntax is incorrect; should be {{token}}.

B. Token variable is not set anywhere.

C. Bearer keyword is missing.

D. Headers do not support variables.

Solution

1. Step 1: Check the variable syntax in the header

   The header uses {token} which is missing one pair of curly braces.

2. Step 2: Correct the syntax to {{token}}

   Postman requires double curly braces to recognize variables, so it should be Authorization: Bearer {{token}}.

3. Final Answer:

   Variable syntax is incorrect; should be {{token}}. -> Option A

4. Quick Check:

   Correct variable syntax = {{variable}} [OK]

Hint: Always use double curly braces {{}} for variables in headers too [OK]

Common Mistakes:

• Using single braces instead of double
• Assuming variables auto-replace without braces
• Not setting the variable value before use

5. You want to reuse a variable sessionId inside a JSON body and a header in Postman. Which is the best practice to ensure it works correctly?

hard

A. Set sessionId as an environment variable and use {{sessionId}} in both places.

B. Write sessionId value directly in JSON and header without variables.

C. Use different variable syntaxes in JSON and header for safety.

D. Set sessionId only in the header; JSON will inherit it automatically.

Solution

1. Step 1: Understand variable scope and reuse in Postman

   Environment variables are accessible throughout the request, including headers and body.

2. Step 2: Use consistent variable syntax {{sessionId}} in both JSON body and header

   This ensures Postman replaces the variable correctly wherever it appears.

3. Final Answer:

   Set sessionId as an environment variable and use {{sessionId}} in both places. -> Option A

4. Quick Check:

   Use environment variables + {{variable}} syntax for reuse [OK]

Hint: Set once as environment variable, use {{variable}} everywhere [OK]

Common Mistakes:

• Hardcoding values instead of variables
• Using inconsistent variable syntax
• Assuming variables auto-share without setting scope