Symfony 2 Dynamic Router

DynamicRouterController.php

<?php

namespace Acme\ContentBundle\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\Controller;
use Symfony\Component\HttpFoundation\Request;

/**
 * Dynamic router controller
 *
 * Tries to locate resources by a given path.
 */
class DynamicRouterController extends Controller
{
    /**
     * Dynamic content loader
     *
     * Takes the resource path and search for it in the content table.
     *
     * @param Request $request
     * @param $guid
     * @return \Symfony\Component\HttpFoundation\Response
     */
    public function getResourceByGuidAction(Request $request, $guid)
    {
        $contentService = $this->get('acme.content.content.service');

        // Redirect /wiki to /wiki/main-page
        if ($guid === 'wiki') {
            return $this->redirect('/wiki/main-page', 301);
        }

        $entity = $contentService->findOneByGuid($guid);
        if (!$entity) {
            throw $this->createNotFoundException(sprintf('No resource found for "%s /%s"',
                $request->getMethod(),
                $guid
            ));
        }

        // TODO: Do some tests to check if the content is already published and not yet expired

        return $this->render('AcmeContentBundle:Content:get.html.twig', array(
            'entity' => $entity
        ));
    }
}

routing.xml

<?xml version="1.0" encoding="UTF-8" ?>

<routes xmlns="http://symfony.com/schema/routing"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://symfony.com/schema/routing http://symfony.com/schema/routing/routing-1.0.xsd">

    <!-- This is the dynamic content loader, it should always be last! -->
    <route id="content.guid" path="/{guid}">
        <default key="_controller">AcmeContentBundle:DynamicRouter:getResourceByGuid</default>
        <requirement key="_method">get</requirement>
        <requirement key="guid">.+</requirement>
    </route>
</routes>