BanMiddleware.php

<?php

namespace Drupal\ban;

use Drupal\Component\Render\FormattableMarkup;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpKernel\HttpKernelInterface;

/**
 * Provides a HTTP middleware to implement IP based banning.
 */
class BanMiddleware implements HttpKernelInterface {
    
    /**
     * The decorated kernel.
     *
     * @var \Symfony\Component\HttpKernel\HttpKernelInterface
     */
    protected $httpKernel;
    
    /**
     * The ban IP manager.
     *
     * @var \Drupal\ban\BanIpManagerInterface
     */
    protected $banIpManager;
    
    /**
     * Constructs a BanMiddleware object.
     *
     * @param \Symfony\Component\HttpKernel\HttpKernelInterface $http_kernel
     *   The decorated kernel.
     * @param \Drupal\ban\BanIpManagerInterface $manager
     *   The ban IP manager.
     */
    public function __construct(HttpKernelInterface $http_kernel, BanIpManagerInterface $manager) {
        $this->httpKernel = $http_kernel;
        $this->banIpManager = $manager;
    }
    
    /**
     * {@inheritdoc}
     */
    public function handle(Request $request, $type = self::MASTER_REQUEST, $catch = TRUE) : Response {
        $ip = $request->getClientIp();
        if ($this->banIpManager
            ->isBanned($ip)) {
            return new Response(new FormattableMarkup('@ip has been banned', [
                '@ip' => $ip,
            ]), 403);
        }
        return $this->httpKernel
            ->handle($request, $type, $catch);
    }

}