Authentication guards in Laravel - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if the user is authenticated using the default guard.

Laravel

<?php
if (Auth::[1]()) {
    // User is authenticated
}

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

Acheck

Bguest

Cuser

Dattempt

Attempts:

3 left

💡 Hint

Common Mistakes

Using guest() instead of check()

Using attempt() which is for login attempts

The check() method returns true if the user is authenticated with the default guard.

2fill in blank

medium

Complete the code to get the currently authenticated user from the 'admin' guard.

Laravel

<?php
$user = Auth::guard('[1]')->user();

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

Aweb

Bapi

Cadmin

Dguest

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'web' guard instead of 'admin'

Using 'guest' which is not a guard name

The guard('admin') specifies the 'admin' guard to get the authenticated user from.

3fill in blank

hard

Fix the error in the code to log out the user from the 'api' guard.

Laravel

<?php
Auth::guard('[1]')->[2]();

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

Aapi

Blogout

Clogin

Duser

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'login' instead of 'logout'

Not specifying the guard name

The first blank must be the guard name 'api' to specify which guard to log out from.

4fill in blank

hard

Fill both blanks to check if the user is a guest on the 'web' guard.

Laravel

<?php
if (Auth::guard('[1]')->[2]()) {
    // User is a guest
}

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

Aweb

Bguest

Ccheck

Dapi

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'check()' instead of 'guest()'

Using 'api' guard instead of 'web'

The 'web' guard is specified first, then the guest() method checks if the user is not authenticated.

5fill in blank

hard

Fill all three blanks to attempt login with email and password on the 'admin' guard.

Laravel

<?php
$credentials = ['email' => $email, 'password' => $password];
if (Auth::guard('[1]')->[2]([3])) {
    // Login successful
}

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

Aadmin

Battempt

C$credentials

Dweb

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'web' guard instead of 'admin'

Using 'login' instead of 'attempt'

Passing wrong variable instead of credentials

The 'admin' guard is used, the attempt() method tries to log in with the given credentials array.

Practice

1. What is the main purpose of an authentication guard in Laravel?

easy

A. To manage session timeouts

B. To store user passwords securely

C. To define database connections

D. To control how users are authenticated for each request

Solution

1. Step 1: Understand the role of authentication guards

   Guards determine how users are authenticated on each request, like checking credentials or tokens.

2. Step 2: Differentiate guards from other features

   Guards do not store passwords, manage sessions, or define databases; those are handled elsewhere.

3. Final Answer:

   To control how users are authenticated for each request -> Option D

4. Quick Check:

   Authentication guard = controls user authentication [OK]

Hint: Guards decide how users log in and access app [OK]

Common Mistakes:

• Confusing guards with password storage
• Thinking guards manage database connections
• Assuming guards handle session timeouts

2. Which of the following is the correct way to specify a guard in Laravel's auth.php config file?

easy

A. 'guards' => ['web' => ['driver' => 'database', 'provider' => 'users']]

B. 'guards' => ['web' => ['driver' => 'token', 'provider' => 'admins']]

C. 'guards' => ['web' => ['driver' => 'session', 'provider' => 'users']]

D. 'guards' => ['api' => ['driver' => 'session', 'provider' => 'users']]

Solution

1. Step 1: Check the standard guard configuration

   Laravel's default 'web' guard uses 'session' driver and 'users' provider.

2. Step 2: Validate driver and provider correctness

   'database' is not a valid driver for guards; 'token' is used for API guards, but 'web' uses 'session'.

3. Final Answer:

   'guards' => ['web' => ['driver' => 'session', 'provider' => 'users']] -> Option C

4. Quick Check:

   Default web guard uses session driver [OK]

Hint: Web guard uses session driver and users provider [OK]

Common Mistakes:

• Using 'database' as a driver instead of 'session'
• Mixing 'token' driver with 'web' guard
• Assigning wrong provider names

3. Given this code snippet in a Laravel controller:

if (Auth::guard('admin')->check()) {
    return 'Admin logged in';
} else {
    return 'No admin logged in';
}

What will be the output if no admin user is logged in but a regular user is?

medium

A. No admin logged in

B. Error: guard not found

C. Admin logged in

D. No output

Solution

1. Step 1: Understand what Auth::guard('admin')->check() does

   This checks if a user is logged in using the 'admin' guard specifically.

2. Step 2: Analyze the scenario

   No admin user is logged in, so check() returns false, even if a regular user is logged in under a different guard.

3. Final Answer:

   No admin logged in -> Option A

4. Quick Check:

   Guard check false means no user logged in for that guard [OK]

Hint: Guard check only sees users of that guard [OK]

Common Mistakes:

• Assuming any logged-in user passes the guard check
• Confusing guard names
• Expecting error if guard exists

4. Identify the error in this Laravel guard usage:

Auth::guard('web')->login($user);
if (Auth::check()) {
    return 'User logged in';
}

medium

A. No error, code works correctly

B. Auth::check() does not check the 'web' guard by default

C. Missing middleware to protect the route

D. Auth::guard('web')->login() requires a user ID, not a user object

Solution

1. Step 1: Understand Auth::guard('web')->login()

   This logs in the user using the 'web' guard explicitly.

2. Step 2: Check what Auth::check() does

   Auth::check() uses the default guard, which may not be 'web', so it might not detect the login.

3. Final Answer:

   Auth::check() does not check the 'web' guard by default -> Option B

4. Quick Check:

   Auth::check() uses default guard, not necessarily 'web' [OK]

Hint: Auth::check() uses default guard, not specified guard [OK]

Common Mistakes:

• Assuming Auth::check() checks all guards
• Thinking login() needs user ID only
• Ignoring middleware importance

5. You want to protect an admin route so only users authenticated with the 'admin' guard can access it. Which is the correct way to apply this in Laravel's route definition?

hard

A. Route::middleware('auth:admin')->group(function () { Route::get('/admin', fn() => 'Admin area'); });

B. Route::middleware('auth:web')->group(function () { Route::get('/admin', fn() => 'Admin area'); });

C. Route::middleware('guest:admin')->group(function () { Route::get('/admin', fn() => 'Admin area'); });

D. Route::middleware('auth')->group(function () { Route::get('/admin', fn() => 'Admin area'); });

Solution

1. Step 1: Understand middleware usage for guards

   The 'auth' middleware accepts a guard name to specify which guard to check for authentication.

2. Step 2: Choose the middleware that checks 'admin' guard

   'auth:admin' ensures only users authenticated with 'admin' guard access the route.

3. Step 3: Eliminate incorrect options

   'auth:web' checks the wrong guard, 'guest:admin' checks for unauthenticated users, and 'auth' without guard uses default guard.

4. Final Answer:

   Route::middleware('auth:admin')->group(function () { Route::get('/admin', fn() => 'Admin area'); }); -> Option A

5. Quick Check:

   Use 'auth:guardname' middleware to protect routes [OK]

Hint: Use 'auth:admin' middleware to protect admin routes [OK]

Common Mistakes:

• Using 'auth' without specifying guard
• Using 'guest' middleware instead of 'auth'
• Applying wrong guard name in middleware