Symfony CMF Dynamic Router no contentDocument - symfony

Question

Following the Dynamic Router doc, I can:
Create a route linked to my content (Page entity)
Persist it with ORM
Load my controller matching the route
But as my controller should expect the $contentDocument parameter, I have nothing.
Here's how I create my route and my entity:
$page = new Page();
$page->setTitle('My Content')
->setBackground(1)
->setDescription('My description')
->setContent('<h1>Hello</h1>');
$manager->persist($page);
$manager->flush(); // flush to be able to use the generated id
$contentRepository = $this->container->get('cmf_routing.content_repository');
$route = new Route();
$route->setName('my-content');
$route->setStaticPrefix('/my-content');
$route->setDefault(RouteObjectInterface::CONTENT_ID, $contentRepository->getContentId($page));
$route->setContent($page);
$page->addRoute($route); // Create the backlink from content to route
$manager->persist($page);
$manager->flush();
Here's my config section:
cmf_routing:
chain:
routers_by_id:
router.default: 200
cmf_routing.dynamic_router: 100
dynamic:
enabled: true
persistence:
orm:
enabled: true
generic_controller: AppBundle:Default:showPage
templates_by_class:
AppBundle\Entity\Page: AppBundle:Default:index.html.twig
My controller:
public function showPageAction($page)
{
return $this->render('default/index.html.twig');
}
And the error:
Controller "AppBundle\Controller\DefaultController::showPageAction()" requires that you provide a value for the "$page" argument. Either the argument is nullable and no null value has been provided, no default value has been provided or because there is a non optional argument after this one.

Answer 1

Dynamic routing puts the content document into the request with the name "contentDocument". You need to explicitly use that name:
public function showPageAction($contentDocument)
{
return $this->render('default/index.html.twig');
}
if you do not need to do anything in your controller, you don't need to specify the generic_controller. template_by_class will make the bundle provided controller render that template with the page instance found in $contentDocument.