<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace App\EventSubscriber;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\HttpFoundation\RedirectResponse;
use Symfony\Component\HttpKernel\Event\RequestEvent;
use Symfony\Component\HttpKernel\KernelEvents;
use Symfony\Component\Routing\Generator\UrlGeneratorInterface;
/**
* When visiting the homepage, this listener redirects the user to the most
* appropriate localized version according to the browser settings.
*
* See https://symfony.com/doc/current/components/http_kernel/introduction.html#the-kernel-request-event
*
* @author Oleg Voronkovich <oleg-voronkovich@yandex.ru>
*/
class RedirectToPreferredLocaleSubscriber implements EventSubscriberInterface
{
private $urlGenerator;
private $locales;
private $defaultLocale;
public function __construct(UrlGeneratorInterface $urlGenerator, string $locales, string $defaultLocale = null)
{
$this->urlGenerator = $urlGenerator;
$this->locales = explode('|', trim($locales));
if (empty($this->locales)) {
throw new \UnexpectedValueException('The list of supported locales must not be empty.');
}
$this->defaultLocale = $defaultLocale ?: $this->locales[0];
if (!\in_array($this->defaultLocale, $this->locales, true)) {
throw new \UnexpectedValueException(sprintf('The default locale ("%s") must be one of "%s".', $this->defaultLocale, $locales));
}
// Add the default locale at the first position of the array,
// because Symfony\HttpFoundation\Request::getPreferredLanguage
// returns the first element when no an appropriate language is found
array_unshift($this->locales, $this->defaultLocale);
$this->locales = array_unique($this->locales);
}
public static function getSubscribedEvents(): array
{
return [
KernelEvents::REQUEST => 'onKernelRequest',
];
}
public function onKernelRequest(RequestEvent $event): void
{
$request = $event->getRequest();
// Ignore sub-requests and all URLs but the homepage
if (!$event->isMasterRequest() || '/' !== $request->getPathInfo()) {
return;
}
// Ignore requests from referrers with the same HTTP host in order to prevent
// changing language for users who possibly already selected it for this application.
if (0 === mb_stripos($request->headers->get('referer'), $request->getSchemeAndHttpHost())) {
return;
}
$preferredLanguage = $request->getPreferredLanguage($this->locales);
if ($preferredLanguage !== $this->defaultLocale) {
$response = new RedirectResponse($this->urlGenerator->generate('homepage', ['_locale' => $preferredLanguage]));
$event->setResponse($response);
}
}
}