symfony2-twig-extension-container.php

<?php

# src/Acme/HelloBundle/Twig/AcmeExtension.php
namespace Acme\HelloBundle\Twig;

use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\Locale\Locale;

class AcmeExtension extends \Twig_Extension
{
    protected $container;

    public function __construct(ContainerInterface $container)
    {
        $this->container = $container;
    }   

    public function getGlobals()
    {
        // Either just return the container available in templates, so to get parameters: {{ container.getParameter('param') }}
        return array(
            'container' => $this->container,
        );

        // OR make every parameter a twig global variable
        $params = $this->container->getParameterBag()->all();
        $params['container'] = $this->container;

        return $params;
    }

    public function getName()
    {
        return 'acme_extension';
    }
}

# src/Acme/HelloBundle/Resources/config/services.yml
services:
    acme.twig.acme_extension:
        class: Acme\HelloBundle\Twig\AcmeExtension
        arguments: [@service_container]
        tags:
            - { name: twig.extension }