Throttle for form requests

[SeagleDub]

I needed the limit to work only if the request parameters were successfully validated. So I created a middleware that only hits when the request was successful. This will only work with a request that extends FormRequest class.

use Closure;
use Illuminate\Routing\Middleware\ThrottleRequests;

class ThrottleFormRequests extends ThrottleRequests
{
    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure  $next
     * @param  array  $limits
     * @return \Symfony\Component\HttpFoundation\Response
     *
     * @throws \Illuminate\Http\Exceptions\ThrottleRequestsException
     */
    protected function handleRequest($request, Closure $next, array $limits)
    {
        foreach ($limits as $limit) {
            if ($this->limiter->tooManyAttempts($limit->key, $limit->maxAttempts)) {
                throw $this->buildException($request, $limit->key, $limit->maxAttempts, $limit->responseCallback);
            }
        }

        $request->attributes->set('throttle_limits', `$limits);`

        $response = $next($request);

        foreach ($limits as $limit) {
            $response = $this->addHeaders(
                $response,
                $limit->maxAttempts,
                $this->calculateRemainingAttempts($limit->key, $limit->maxAttempts)
            );
        }

        return $response;
    }
}

It was also necessary to add logic to the form request class.

class FormRequest extends \Illuminate\Foundation\Http\FormRequest
{
    /**
     * Handle a passed validation attempt.
     *
     * @return void
     */
    protected function passedValidation()
    {
        $limits = (array) $this->attributes->get('throttle_limits');
        if(!empty($limits)){
            foreach ($limits as $limit) {
                \RateLimiter::hit($limit->key, $limit->decayMinutes * 60);
            }
        }
    }
}

Finally, it was necessary to create an alias for the new middleware in Kernel.php file.

protected $routeMiddleware = [
     ...
    'throttle.form' => \App\Http\Middleware\ThrottleFormRequests::class
];

Now we can use the default rate limit, which will only hit on a successful form request. The only thing is to change the name of the middleware from throttle to throttle.form.