BlockComponentRenderArray.php in Drupal 8

Namespace

Drupal\layout_builder\EventSubscriber

File

core/modules/layout_builder/src/EventSubscriber/BlockComponentRenderArray.php

<?php

namespace Drupal\layout_builder\EventSubscriber;

use Drupal\block_content\Access\RefinableDependentAccessInterface;
use Drupal\Core\Access\AccessResult;
use Drupal\Core\Block\BlockPluginInterface;
use Drupal\Core\Cache\CacheableMetadata;
use Drupal\Core\Render\Element;
use Drupal\Core\Render\PreviewFallbackInterface;
use Drupal\Core\Session\AccountInterface;
use Drupal\Core\StringTranslation\StringTranslationTrait;
use Drupal\layout_builder\Access\LayoutPreviewAccessAllowed;
use Drupal\layout_builder\Event\SectionComponentBuildRenderArrayEvent;
use Drupal\layout_builder\LayoutBuilderEvents;
use Drupal\views\Plugin\Block\ViewsBlock;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

/**
 * Builds render arrays and handles access for all block components.
 *
 * @internal
 *   Tagged services are internal.
 */
class BlockComponentRenderArray implements EventSubscriberInterface {
  use StringTranslationTrait;

  /**
   * The current user.
   *
   * @var \Drupal\Core\Session\AccountInterface
   */
  protected $currentUser;

  /**
   * Creates a BlockComponentRenderArray object.
   *
   * @param \Drupal\Core\Session\AccountInterface $current_user
   *   The current user.
   */
  public function __construct(AccountInterface $current_user) {
    $this->currentUser = $current_user;
  }

  /**
   * {@inheritdoc}
   */
  public static function getSubscribedEvents() {
    $events[LayoutBuilderEvents::SECTION_COMPONENT_BUILD_RENDER_ARRAY] = [
      'onBuildRender',
      100,
    ];
    return $events;
  }

  /**
   * Builds render arrays for block plugins and sets it on the event.
   *
   * @param \Drupal\layout_builder\Event\SectionComponentBuildRenderArrayEvent $event
   *   The section component render event.
   */
  public function onBuildRender(SectionComponentBuildRenderArrayEvent $event) {
    $block = $event
      ->getPlugin();
    if (!$block instanceof BlockPluginInterface) {
      return;
    }

    // Set block access dependency even if we are not checking access on
    // this level. The block itself may render another
    // RefinableDependentAccessInterface object and need to pass on this value.
    if ($block instanceof RefinableDependentAccessInterface) {
      $contexts = $event
        ->getContexts();
      if (isset($contexts['layout_builder.entity'])) {
        if ($entity = $contexts['layout_builder.entity']
          ->getContextValue()) {
          if ($event
            ->inPreview()) {

            // If previewing in Layout Builder allow access.
            $block
              ->setAccessDependency(new LayoutPreviewAccessAllowed());
          }
          else {
            $block
              ->setAccessDependency($entity);
          }
        }
      }
    }

    // Only check access if the component is not being previewed.
    if ($event
      ->inPreview()) {
      $access = AccessResult::allowed()
        ->setCacheMaxAge(0);
    }
    else {
      $access = $block
        ->access($this->currentUser, TRUE);
    }
    $event
      ->addCacheableDependency($access);
    if ($access
      ->isAllowed()) {
      $event
        ->addCacheableDependency($block);

      // @todo Revisit after https://www.drupal.org/node/3027653, as this will
      //   provide a better way to remove contextual links from Views blocks.
      //   Currently, doing this requires setting
      //   \Drupal\views\ViewExecutable::$showAdminLinks() to false before the
      //   Views block is built.
      if ($block instanceof ViewsBlock && $event
        ->inPreview()) {
        $block
          ->getViewExecutable()
          ->setShowAdminLinks(FALSE);
      }
      $content = $block
        ->build();

      // We don't output the block render data if there are no render elements
      // found, but we want to capture the cache metadata from the block
      // regardless.
      $event
        ->addCacheableDependency(CacheableMetadata::createFromRenderArray($content));
      $is_content_empty = Element::isEmpty($content);
      $is_placeholder_ready = $event
        ->inPreview() && $block instanceof PreviewFallbackInterface;

      // If the content is empty and no placeholder is available, return.
      if ($is_content_empty && !$is_placeholder_ready) {
        return;
      }
      $build = [
        // @todo Move this to BlockBase in https://www.drupal.org/node/2931040.
        '#theme' => 'block',
        '#configuration' => $block
          ->getConfiguration(),
        '#plugin_id' => $block
          ->getPluginId(),
        '#base_plugin_id' => $block
          ->getBaseId(),
        '#derivative_plugin_id' => $block
          ->getDerivativeId(),
        '#weight' => $event
          ->getComponent()
          ->getWeight(),
        'content' => $content,
      ];
      if ($event
        ->inPreview()) {
        if ($block instanceof PreviewFallbackInterface) {
          $preview_fallback_string = $block
            ->getPreviewFallbackString();
        }
        else {
          $preview_fallback_string = $this
            ->t('"@block" block', [
            '@block' => $block
              ->label(),
          ]);
        }

        // @todo Use new label methods so
        //   data-layout-content-preview-placeholder-label doesn't have to use
        //   preview fallback in https://www.drupal.org/node/2025649.
        $build['#attributes']['data-layout-content-preview-placeholder-label'] = $preview_fallback_string;
        if ($is_content_empty && $is_placeholder_ready) {
          $build['content']['#markup'] = $this
            ->t('Placeholder for the @preview_fallback', [
            '@preview_fallback' => $block
              ->getPreviewFallbackString(),
          ]);
        }
      }
      $event
        ->setBuild($build);
    }
  }

}

Classes

Name	Description
BlockComponentRenderArray	Builds render arrays and handles access for all block components.