Middleware in Laravel allows you to filter HTTP requests entering your application. It provides a convenient mechanism to perform actions before a request is handled by the application's route or after the response has been generated. In this post, we'll walk through a step-by-step guide on how to create custom middleware in Laravel, giving you the flexibility to add custom logic to your application's request flow.

Step 1: Create the Middleware

To create custom middleware in Laravel, use the make:middleware Artisan command:

php artisan make:middleware CustomMiddleware

This will generate a new middleware class file named CustomMiddleware.php in the app/Http/Middleware directory.

Step 2: Define the Middleware Logic

Open the CustomMiddleware.php file and implement the middleware logic in the handle method. This method will be called for every incoming request that passes through this middleware.

<?php

namespace App\Http\Middleware;

use Closure;

class CustomMiddleware
{
    public function handle($request, Closure $next)
    {
        // Middleware logic goes here

        return $next($request);
    }
}

Step 3: Register the Middleware

To use the custom middleware, you need to register it in the app/Http/Kernel.php file. Open the file and add your middleware to the $middleware array or the $routeMiddleware array if you want to use it for specific routes.

protected $middleware = [
    // Other middleware
    \App\Http\Middleware\CustomMiddleware::class,
];

// Or, for route-specific usage
protected $routeMiddleware = [
    // Other middleware
    'custom' => \App\Http\Middleware\CustomMiddleware::class,
];

Step 4: Applying Middleware to Routes

Now that your custom middleware is registered, you can apply it to routes in your routes/web.php or routes/api.php file.

// Apply middleware to individual routes
Route::get('/example', function () {
    // Your route logic here
})->middleware('custom');

// Apply middleware to a group of routes
Route::middleware('custom')->group(function () {
    // Your routes here
});

Step 5: Middleware Logic

Custom middleware can perform various tasks, such as authentication, authorization, logging, modifying request/response, and more. For example, let's add a simple logging functionality to our custom middleware:

<?php

namespace App\Http\Middleware;

use Closure;
use Illuminate\Support\Facades\Log;

class CustomMiddleware
{
    public function handle($request, Closure $next)
    {
        // Log the incoming request details
        Log::info('Incoming request:', [
            'method' => $request->method(),
            'path' => $request->path(),
            'params' => $request->all(),
        ]);

        return $next($request);
    }
}

Step 6: Testing the Custom Middleware

With the custom middleware implemented, run your Laravel application and access the routes where the middleware is applied. You should see the logged request details in your application's log file.

Creating custom middleware in Laravel provides a powerful way to add reusable and flexible logic to your application's request flow. Whether it's authentication, logging, or any other custom functionality, middleware allows you to intercept requests and perform actions before they reach the route handlers.