Drupal 10 filter plugin (mymodule/src/Plugin/Filter) for importing media by Feeds GUID

MediaFeedsEmbed.php

<?php

namespace Drupal\my_module\Plugin\Filter;

use Drupal\Component\Utility\Html;
use Drupal\Core\Entity\EntityDisplayRepositoryInterface;
use Drupal\Core\Security\TrustedCallbackInterface;
use Drupal\filter\FilterProcessResult;
use Drupal\media\MediaInterface;
use Drupal\media\Plugin\Filter\MediaEmbed;

/**
 * Provides a filter to embed media items using a custom tag.
 *
 * @Filter(
 *   id = "media_feeds_embed",
 *   title = @Translation("Embed feeds media"),
 *   description = @Translation("Embeds media items using a custom tag, <code>&lt;feeds-media&gt;</code>. If used in conjunction with the 'Align/Caption' filters, make sure this filter is configured to run after them."),
 *   type = Drupal\filter\Plugin\FilterInterface::TYPE_TRANSFORM_REVERSIBLE,
 *   settings = {
 *     "default_view_mode" = "default",
 *     "allowed_view_modes" = {},
 *     "allowed_media_types" = {},
 *   },
 *   weight = 100,
 * )
 *
 * @internal
 */
class MediaFeedsEmbed extends MediaEmbed implements TrustedCallbackInterface {
  /**
   * {@inheritdoc}
   */
  public function process($text, $langcode) {
    $result = new FilterProcessResult($text);

    if (stristr($text, '<feeds-media') === FALSE) {
      return $result;
    }

    $dom = Html::load($text);
    $xpath = new \DOMXPath($dom);

    foreach ($xpath->query('//feeds-media[normalize-space(@data-entity-guid)!=""]') as $node) {
      /** @var \DOMElement $node */
      $feeds_guid = $node->getAttribute('data-entity-guid');
      $view_mode_id = $node->getAttribute('data-view-mode') ?: $this->settings['default_view_mode'];

      // Delete the consumed attributes.
      $node->removeAttribute('data-entity-guid');
      $node->removeAttribute('data-view-mode');

      $media_load_by_properties = $this->entityTypeManager->getStorage('media')
        ->loadByProperties(['feeds_item.guid' => $feeds_guid]);
      // loadByProperties() can return multiple.
      // It will only return a single value in this case (because only 1 GUID),
      // but we need to reset it anyway b/c Drupal doesn't know that.
      $media = reset($media_load_by_properties);
      assert($media === NULL || $media instanceof MediaInterface, "Failed to load guid $feeds_guid for rendering.");
      if (!$media) {
        $this->loggerFactory->get('media')->error('During rendering of embedded media: the media item with UUID "@feeds_guid" does not exist.', ['@feeds_guid' => $feeds_guid]);
      }
      else {
        $media = $this->entityRepository->getTranslationFromContext($media, $langcode);
        $media = clone $media;
        $this->applyPerEmbedMediaOverrides($node, $media);
      }

      $view_mode = NULL;
      if ($view_mode_id !== EntityDisplayRepositoryInterface::DEFAULT_DISPLAY_MODE) {
        $view_mode = $this->entityRepository->loadEntityByConfigTarget('entity_view_mode', "media.$view_mode_id");
        if (!$view_mode) {
          $this->loggerFactory->get('media')->error('During rendering of embedded media: the view mode "@view-mode-id" does not exist.', ['@view-mode-id' => $view_mode_id]);
        }
      }

      $build = $media && ($view_mode || $view_mode_id === EntityDisplayRepositoryInterface::DEFAULT_DISPLAY_MODE)
        ? $this->renderMedia($media, $view_mode_id, $langcode)
        : $this->renderMissingMediaIndicator();

      if (empty($build['#attributes']['class'])) {
        $build['#attributes']['class'] = [];
      }
      // Any attributes not consumed by the filter should be carried over to the
      // rendered embedded entity. For example, `data-align` and `data-caption`
      // should be carried over, so that even when embedded media goes missing,
      // at least the caption and visual structure won't get lost.
      foreach ($node->attributes as $attribute) {
        if ($attribute->nodeName == 'class') {
          // We don't want to overwrite the existing CSS class of the embedded
          // media (or if the media entity can't be loaded, the missing media
          // indicator). But, we need to merge in CSS classes added by other
          // filters, such as filter_align, in order for those filters to work
          // properly.
          $build['#attributes']['class'] = array_unique(array_merge($build['#attributes']['class'], explode(' ', $attribute->nodeValue)));
        }
        else {
          $build['#attributes'][$attribute->nodeName] = $attribute->nodeValue;
        }
      }

      $this->renderIntoDomNode($build, $node, $result);
    }

    $result->setProcessedText(Html::serialize($dom));

    return $result;
  }

  /**
   * {@inheritdoc}
   */
  public function tips($long = FALSE) {
    if ($long) {
      return $this->t('
      <p>You can embed media items:</p>
      <ul>
        <li>Choose which media item to embed: <code>&lt;feeds-media data-entity-guid="my-feeds-id" /&gt;</code></li>
        <li>Optionally also choose a view mode: <code>data-view-mode="tiny_embed"</code>, otherwise the default view mode is used.</li>
      </ul>');
    }
    else {
      return $this->t('You can embed media items (using the <code>&lt;feeds-media&gt;</code> tag).');
    }
  }

}