MainContentViewSubscriber::onViewRenderArray

public MainContentViewSubscriber::onViewRenderArray(GetResponseForControllerResultEvent $event)

public function onViewRenderArray(GetResponseForControllerResultEvent $event) {
  $request = $event->getRequest();
  $result = $event->getControllerResult();

  // Render the controller result into a response if it's a render array.
  if (is_array($result) && ($request->query->has(static::WRAPPER_FORMAT) || $request->getRequestFormat() == 'html')) {
    $wrapper = $request->query->get(static::WRAPPER_FORMAT, 'html');

    // Fall back to HTML if the requested wrapper envelope is not available.
    $wrapper = isset($this->mainContentRenderers[$wrapper]) ? $wrapper : 'html';

    $renderer = $this->classResolver->getInstanceFromDefinition($this->mainContentRenderers[$wrapper]);
    $response = $renderer->renderResponse($result, $request, $this->routeMatch);
    // The main content render array is rendered into a different Response
    // object, depending on the specified wrapper format.
    if ($response instanceof CacheableResponseInterface) {
      $main_content_view_subscriber_cacheability = (new CacheableMetadata())->setCacheContexts(['url.query_args:' . static::WRAPPER_FORMAT]);
      $response->addCacheableDependency($main_content_view_subscriber_cacheability);
    }
    $event->setResponse($response);
  }
}