How to configure Symfony2 sticky locale during session - php

Question

I would like to translate my website thanks to an link on the right top.
I found out that, since Symfony 2.1, the locale is not stored in the session anymore.
So, I followed this Symfony documentation: Making the Locale "Sticky" during a User's Session
...Bundle/Service/LocaleListener.php
class LocaleListener implements EventSubscriberInterface
{
private $defaultLocale;
public function __construct($defaultLocale)
{
$this->defaultLocale = $defaultLocale;
}
public function onKernelRequest(GetResponseEvent $event)
{
$request = $event->getRequest();
if (!$request->hasPreviousSession()) {
return;
}
$locale = $request->attributes->get('_locale');
var_dump($locale);
if ($locale) {
$request->getSession()->set('_locale', $locale);
} else {
$request->setLocale($request->getSession()->get('_locale', $this->defaultLocale));
}
}
static public function getSubscribedEvents()
{
return array(
// must be registered before the default Locale listener
KernelEvents::REQUEST => array(array('onKernelRequest', 17)),
);
}
}
...Bundle/Resources/config/services.yml
locale_listener:
class: ..Bundle\Service\LocaleListener
arguments: ["%kernel.default_locale%"]
tags:
- { name: kernel.event_subscriber }
./app/config/config.yml
framework:
translator: { fallback: en }
And, I add two links to translate my website on the parent twig template, shown below (Symfony2 locale languages whole page event listener).
base.html.twig
<li><a href="{{-
path(app.request.get('_route'),
app.request.get('_route_params')|merge({'_locale' : 'fr'}))
-}}">FR</a></li>
<li><a href="{{-
path(app.request.get('_route'),
app.request.get('_route_params')|merge({'_locale' : 'en'}))
-}}">EN</a></li>
Problem and Question
When I click on one of these links, the parameter _locale is added.
For instance:
satisfaction?_locale=fr
So, the value of the _locale parameter is fr. Consequently, my website should be translated in french.
Nevertheless, that
var_dump($locale)
in the listener is displayed three times:
null
en
null
I don't understand why the _locale parameter is not found when it display null and why the en?

Answer 1

With your listener, you will catch all request and subrequest that is not needed. This explain the three times apparition.
Try to add this following code to your onKernelRequest method:
if (HttpKernel::MASTER_REQUEST != $event->getRequestType()) {
return;
}
This will avoid subRequests and possibly resolve your problem.