Registering middleware in Laravel - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to register a middleware in the HTTP kernel.

Laravel

protected $middleware = [
    \App\Http\Middleware\CheckForMaintenanceMode::class,
    [1]
];

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

A\App\Http\Middleware\TrimStrings::class

B\App\Http\Middleware\RedirectIfAuthenticated::class

C\App\Http\Middleware\Authenticate::class

D\App\Http\Middleware\VerifyCsrfToken::class

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing middleware that is only for route groups or guards.

Confusing middleware classes that are registered in $routeMiddleware.

The TrimStrings middleware is commonly registered globally in the $middleware array in app/Http/Kernel.php.

2fill in blank

medium

Complete the code to assign middleware to a route group in the kernel.

Laravel

protected $middlewareGroups = [
    'web' => [
        \App\Http\Middleware\EncryptCookies::class,
        [1],
        \App\Http\Middleware\ShareErrorsFromSession::class,
    ],
];

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

A\App\Http\Middleware\RedirectIfAuthenticated::class

B\App\Http\Middleware\Authenticate::class

C\App\Http\Middleware\VerifyCsrfToken::class

D\App\Http\Middleware\TrimStrings::class

Attempts:

3 left

💡 Hint

Common Mistakes

Using authentication middleware instead of CSRF verification.

Placing middleware in the wrong group.

The VerifyCsrfToken middleware is part of the web middleware group to protect against CSRF attacks.

3fill in blank

hard

Fix the error in registering a route middleware alias.

Laravel

protected $routeMiddleware = [
    'auth' => [1],
    'guest' => \App\Http\Middleware\RedirectIfAuthenticated::class,
];

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

A\Authenticate::class

B\App\Http\Middleware\Authenticate::class

CAuthenticate::class

D\App\Http\Middleware\Authenticate

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting the ::class suffix.

Using incomplete namespace paths.

Middleware classes must be referenced with the full namespace and ::class suffix to register correctly.

4fill in blank

hard

Fill both blanks to register a custom middleware alias and add it to the 'api' group.

Laravel

protected $routeMiddleware = [
    'checkAge' => [1],
];

protected $middlewareGroups = [
    'api' => [
        'throttle:60,1',
        [2],
    ],
];

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

A\App\Http\Middleware\CheckAge::class

B\App\Http\Middleware\Authenticate::class

CcheckAge

Dauth

Attempts:

3 left

💡 Hint

Common Mistakes

Using the class name instead of the alias in the group.

Forgetting to add the middleware to the group.

The custom middleware class CheckAge is registered with the alias 'checkAge'. This alias is then added to the 'api' middleware group.

5fill in blank

hard

Fill all three blanks to register a middleware alias, add it to a group, and apply it to a route.

Laravel

protected $routeMiddleware = [
    [1] => \App\Http\Middleware\LogAccess::class,
];

protected $middlewareGroups = [
    'web' => [
        [2],
    ],
];

Route::middleware('[3]')->group(function () {
    Route::get('/dashboard', function () {
        return view('dashboard');
    });
});

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

Alog.access

Dauth

Attempts:

3 left

💡 Hint

Common Mistakes

Using different alias names in different places.

Forgetting to add the middleware to the group or route.

The middleware alias 'log.access' is registered, added to the 'web' group, and applied to the route group to log access on those routes.

Practice

1. What is the main purpose of registering middleware in Laravel's Kernel.php file?

easy

A. To define database connections

B. To make middleware available for use in routes and controllers

C. To create new views

D. To register event listeners

Solution

1. Step 1: Understand middleware role

   Middleware acts as a filter for HTTP requests in Laravel.

2. Step 2: Purpose of registering middleware

   Registering middleware in Kernel.php makes it available to assign to routes or groups.

3. Final Answer:

   To make middleware available for use in routes and controllers -> Option B

4. Quick Check:

   Middleware registration = availability for routes [OK]

Hint: Middleware must be registered to use it in routes [OK]

Common Mistakes:

• Confusing middleware registration with database setup
• Thinking middleware creates views
• Mixing middleware with event listeners

2. Which of the following is the correct way to register a route middleware named checkAge in app/Http/Kernel.php?

easy

A. 'checkAge' => \App\Http\Middleware\CheckAge::class,

B. 'checkAge' => 'CheckAgeMiddleware',

C. 'checkAge' => new CheckAge(),

D. 'checkAge' => 'middleware.checkAge',

Solution

1. Step 1: Locate middleware registration syntax

   In Kernel.php, route middleware are registered as key-value pairs with the key as the name and value as the class reference.

2. Step 2: Match correct syntax

   The correct syntax uses the fully qualified class name with ::class keyword.

3. Final Answer:

   'checkAge' => \App\Http\Middleware\CheckAge::class, -> Option A

4. Quick Check:

   Middleware registration uses class reference [OK]

Hint: Use full class path with ::class to register middleware [OK]

Common Mistakes:

• Using string names instead of class references
• Instantiating middleware instead of referencing class
• Using incorrect keys or formats

3. Given the following Kernel.php snippet, what middleware will be applied when accessing the route /profile?

protected $routeMiddleware = [
    'auth' => \App\Http\Middleware\Authenticate::class,
    'verified' => \App\Http\Middleware\EnsureEmailIsVerified::class,
];

Route::middleware(['auth', 'verified'])->get('/profile', function () {
    return 'User Profile';
});

medium

A. Both 'auth' and 'verified' middleware run

B. Only the 'auth' middleware runs

C. No middleware runs

D. Only the 'verified' middleware runs

Solution

1. Step 1: Check middleware registration

   Both 'auth' and 'verified' middleware are registered in $routeMiddleware.

2. Step 2: Analyze route middleware assignment

   The route applies both middleware by listing them in the array ['auth', 'verified'].

3. Final Answer:

   Both 'auth' and 'verified' middleware run -> Option A

4. Quick Check:

   Route middleware array applies all listed middleware [OK]

Hint: All middleware in array run in order [OK]

Common Mistakes:

• Assuming only one middleware runs
• Confusing middleware registration with application
• Ignoring middleware order

4. Identify the error in this middleware registration snippet inside Kernel.php:

protected $routeMiddleware = [
    'admin' => App\Http\Middleware\AdminCheck,
];

medium

A. Middleware should be registered in $middleware property

B. Middleware name 'admin' is invalid

C. Missing the ::class keyword after the middleware class name

D. Namespace should not be used in Kernel.php

Solution

1. Step 1: Review middleware registration syntax

   Middleware classes must be referenced with the ::class keyword to provide the full class name as a string.

2. Step 2: Identify missing part

   The snippet misses ::class after App\Http\Middleware\AdminCheck.

3. Final Answer:

   Missing the ::class keyword after the middleware class name -> Option C

4. Quick Check:

   Middleware class references need ::class [OK]

Hint: Always add ::class after middleware class name [OK]

Common Mistakes:

• Omitting ::class causing syntax errors
• Registering middleware in wrong property
• Using invalid middleware names

5. You want to create a middleware that logs every request to a specific route group. After creating the middleware class, what is the correct way to register and apply it to the route group in Laravel?

hard

A. Use the middleware class name as a string in the route group without registration

B. Add the middleware class directly inside the route group without registration

C. Register the middleware in $middleware property and apply it only to the route group

D. Register the middleware in Kernel.php under $routeMiddleware with a name, then apply it in the route group using middleware('name')

Solution

1. Step 1: Register middleware properly

   Custom middleware must be registered in $routeMiddleware in Kernel.php with a key name.

2. Step 2: Apply middleware to route group

   Use the registered name in the route group with middleware('name') to apply it.

3. Final Answer:

   Register the middleware in Kernel.php under $routeMiddleware with a name, then apply it in the route group using middleware('name') -> Option D

4. Quick Check:

   Register then apply by name for route groups [OK]

Hint: Register middleware name, then use it in route groups [OK]

Common Mistakes:

• Skipping registration and using class name directly
• Registering middleware globally instead of route-specific
• Misplacing middleware registration property