Add Twig global variable after kernel.request event - php

Question

I am currently working on developing a project in SAAS, each client can access his platform by a personalized url (site1.com, site2.com, etc.).
For each domain name a set of template customization data is defined in the back office and I must be able to access it from my Twig files. So I defined a listener on the kernerl.request event that adds a global variable to Twig based on the current domain name. Everything works fine in most cases, except when a page is first displayed, Twig must be run upstream and I get the following error:
Unable to add global "site" as the runtime or the extensions have
already been initialized.
Listener class
class SiteListener
{
public function __construct(
SiteHelper $siteHelper,
\Twig_Environment $twig
) {
$this->siteHelper = $siteHelper;
$this->twig = $twig;
}
/**
* Add current contexts to twig global.
*/
public function addContextsToTwigGlobal(GetResponseEvent $event)
{
$this->twig->addGlobal('site', $this->siteHelper);
}
}
Listener service declaration
multisite.listener.site:
class: MultisiteBundle\Listener\SiteListener
arguments:
- "#multisite.helper.site"
- "#twig"
tags:
- { name: kernel.event_listener, event: kernel.request, method: addContextsToTwigGlobal }
SiteHelper service
class SiteHelper
{
/**
* #var RequestStack
*/
protected $requestStack;
/**
* #var ContextConfigManager;
*/
protected $contextConfigManager;
/**
* #var ContextConfig
*/
protected $contextConfig;
public function __construct(
RequestStack $requestStack,
ContextConfigManager $contextConfigManager
) {
$this->requestStack = $requestStack;
$this->contextConfigManager = $contextConfigManager;
$this->contextConfig = $this->contextConfigManager
->findByHostOrStandard($this->getHost());
}
/**
* Get host from current request.
*
* #return string|null
*/
public function getHost()
{
$request = $this->requestStack->getCurrentRequest();
return ($request) ? $request->getHost() : null;
}
/**
* Get current context config
*
* #return ContextConfig
*/
public function getContextConfig()
{
return $this->contextConfig;
}
}
Any idea ?

Answer 1

I decided to write a Twig function to avoid this kind of problem. This seem to be a good solution.
class SiteExtension extends \Twig_Extension
{
/**
* #var SiteHelper
*/
private $siteHelper;
/**
* Constructor.
*
* #param SiteHelper $siteHelper
*/
public function __construct(SiteHelper $siteHelper)
{
$this->siteHelper = $siteHelper;
}
/**
* {#inheritdoc}
*/
public function getFunctions()
{
return array(
new \Twig_Function('site', array($this->siteHelper, 'getContext')),
);
}
}