Exclude entities which have a redirect from the search api index

For a custom project, we use a taxonomy to tag nodes. Some terms have their own page, while others redirect to a node. The search on the site has one index which contains both nodes and terms, but the terms which are redirecting shouldn't show up when viewing a search results page. While it's possible to use hook_search_api_index_items_alter(), a nicer way to exclude them is by using a processor plugin so you can enable them in the UI per index. The relevant code is underneath. Adjust to your own likings - and maybe inject the service if you want to as well :)

<?php namespace Drupal\project\Plugin\search_api\processor; use Drupal\search_api\IndexInterface; use Drupal\search_api\Processor\ProcessorPluginBase; /**  * Excludes entities which have a redirect.  *  * @SearchApiProcessor(  *   id = "entity_redirect",  *   label = @Translation("Entity redirect"),  *   description = @Translation("Exclude entities which have a redirect from being indexed."),  *   stages = {  *     "alter_items" = 0,  *   },  * )  */ class EntityRedirect extends ProcessorPluginBase {   /**    * {@inheritdoc}    */   public static function supportsIndex(IndexInterface $index) {     foreach ($index->getDatasources() as $datasource) {       $entity_type_id = $datasource->getEntityTypeId();       if (!$entity_type_id) {         continue;       }       if ($entity_type_id === 'node' || $entity_type_id == 'taxonomy_term') {         return TRUE;       }     }     return FALSE;   }   /**    * {@inheritdoc}    */   public function alterIndexedItems(array &$items) {     $repository = \Drupal::service('redirect.repository');     $pathAliasmanager = \Drupal::service('path.alias_manager');     /** @var \Drupal\search_api\Item\ItemInterface $item */     foreach ($items as $item_id => $item) {       $object = $item->getOriginalObject()->getValue();       try {         $path = $object->toUrl()->toString();         $path = $pathAliasmanager->getPathByAlias($path);         $path = ltrim($path, '/');         $redirect = $repository->findMatchingRedirect($path);         if (!empty($redirect)) {           unset($items[$item_id]);         }       }       catch (\Exception $ignored) {}     }   } } ?>

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