cacheDrupalContainer example

    \Drupal::setContainer($this->container);

    // Allow other parts of the codebase to react on container initialization in     // subrequest.     if (!empty($subrequest)) {
      $this->container->get('event_dispatcher')->dispatch(new Event(), self::CONTAINER_INITIALIZE_SUBREQUEST_FINISHED);
    }

    // If needs dumping flag was set, dump the container.     if ($this->containerNeedsDumping && !$this->cacheDrupalContainer($container_definition)) {
      $this->container->get('logger.factory')->get('DrupalKernel')->error('Container cannot be saved to cache.');
    }

    return $this->container;
  }

  /** * Setup a consistent PHP environment. * * This method sets PHP environment options we want to be sure are set * correctly for security or just saneness. * * @param string $app_root * (optional) The path to the application root as a string. If not supplied, * the application root will be computed. */