Stateless authentication mental model in Spring Boot - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to extract the token from the HTTP header.

Spring Boot

String token = request.getHeader([1]);

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A"Authorization"

B"Cookie"

C"Content-Type"

D"User-Agent"

Attempts:

3 left

💡 Hint

Common Mistakes

Using Cookie header instead of Authorization.

Trying to get token from Content-Type or User-Agent headers.

The token is usually sent in the Authorization header in stateless authentication.

2fill in blank

medium

Complete the code to validate the JWT token signature.

Spring Boot

boolean isValid = jwtUtil.validateToken([1]);

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Atoken

Brequest

Cauthentication

DuserDetails

Attempts:

3 left

💡 Hint

Common Mistakes

Passing the whole request object instead of the token string.

Passing user details or authentication objects.

The token string is passed to the validation method to check its signature and claims.

3fill in blank

hard

Fix the error in the code to set the authentication in the security context.

Spring Boot

SecurityContextHolder.getContext().setAuthentication([1]);

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AuserDetails

Btoken

CauthenticationToken

Drequest

Attempts:

3 left

💡 Hint

Common Mistakes

Setting the raw token string instead of an Authentication object.

Passing the request or user details directly.

The authenticationToken object represents the authenticated user and must be set in the security context.

4fill in blank

hard

Fill both blanks to create a JWT token with a subject and expiration.

Spring Boot

String jwt = Jwts.builder().setSubject([1]).setExpiration([2]).compact();

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Ausername

Bnew Date(System.currentTimeMillis() + 3600000)

Cnew Date()

Dpassword

Attempts:

3 left

💡 Hint

Common Mistakes

Using password as subject.

Setting expiration to current date (already expired).

The username is set as the subject, and the expiration is set to one hour from now.

5fill in blank

hard

Fill both blanks to extract username, check expiration, and get claims from JWT.

Spring Boot

Claims claims = Jwts.parser().setSigningKey(secretKey).parseClaimsJws([1]).getBody(); String username = claims.getSubject(); boolean expired = claims.getExpiration().[2](new Date());

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

Atoken

Bafter

Cbefore

Dequals

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'after' instead of 'before' to check expiration.

Parsing something other than the token string.

The token is parsed to get claims. The expiration date is checked if it is before the current date to determine if expired.