added caching

README.md

@@ -12,8 +12,8 @@ it's easy to forget that they [don't work with Term Merge](https://www.drupal.or
 
 # Usage
 1. install
-2. Go to `/admin/zombies` to see the list of problems.
-3. Fix the broken links manually.
+2. Go to `/admin/reports` and select `Zombie Reference Hunter`.
+3. Click on the Source ID to navigate to the edit page.
 
 # Who to Blame
 Rosie Le Faive (rlefaive@upei.ca) and the human behind / the AI Bot that made the original.

src/Controller/ZombieReferenceHunterController.php

@@ -8,6 +8,10 @@ use Drupal\Core\Messenger\MessengerTrait;
 use Drupal\Core\Session\AccountInterface;
 use Drupal\zombie_reference_hunter\Service\ZombieReferenceHunterQuery;
 use Symfony\Component\DependencyInjection\ContainerInterface;
+use Drupal\Core\Link;
+use Drupal\Core\Url;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\RedirectResponse;
 
 /**
  * Creating a controller.
@@ -42,30 +46,108 @@ class ZombieReferenceHunterController extends ControllerBase
    * Returns the Report page.
    *
    */
-  public function view(): array
+  public function view(Request $request): array|RedirectResponse
   {
-    $issues = $this->query->scan();
+    // Force a new scan when requested.
+    if ($request->query->getBoolean('rescan')) {
+      $this->query->rebuildCache();
+
+      // Redirect back to the clean report URL so refreshing the browser
+      // doesn't perform another scan.
+      return new RedirectResponse(
+        Url::fromRoute('zombie_reference_hunter.prepare')->toString()
+      );
+    }
+
+    // This now returns cached results unless no cache exists yet.
+    $issues = $this->query->getIssues();
     $count = count($issues);
+
     $build = [
       '#cache' => ['max-age' => 0],
     ];
 
     $build['summary'] = [
-      '#markup' => $this->t('Found @count broken reference(s).', ['@count' => $count]),
+      '#type' => 'container',
+    ];
+
+    $build['summary']['count'] = [
+      '#markup' => $this->formatPlural(
+        $count,
+        'Found 1 broken reference.',
+        'Found @count broken references.',
+      ),
+    ];
+
+    // Rescan button.
+    $build['summary']['rescan'] = [
+      '#type' => 'link',
+      '#title' => $this->t('Rescan'),
+      '#url' => Url::fromRoute(
+        'zombie_reference_hunter.prepare',
+        [],
+        [
+          'query' => [
+            'rescan' => 1,
+          ],
+        ]
+      ),
+      '#attributes' => [
+        'class' => [
+          'button',
+          'button--primary',
+        ],
+        'style' => 'margin-left: 1em;',
+      ],
     ];
 
     if ($count === 0) {
       $build['empty'] = [
         '#markup' => $this->t('No broken references found.'),
       ];
+
       return $build;
     }
 
+    // Pager.
+    $limit = 50;
+
+    $pager = \Drupal::service('pager.manager')
+      ->createPager($count, $limit);
+
+    $current_page = $pager->getCurrentPage();
+
+    // Only build rows for the current page.
+    $issues = array_slice(
+      $issues,
+      $current_page * $limit,
+      $limit
+    );
+
     $rows = [];
+
     foreach ($issues as $issue) {
+      $entity_type_id = $issue['source_entity_type'];
+      $entity_type = $this->entityTypeManager()
+        ->getDefinition($entity_type_id);
+
+      $source_id = $issue['source_id'];
+
+      if ($entity_type->hasLinkTemplate('edit-form')) {
+        $source_id = Link::fromTextAndUrl(
+          (string) $issue['source_id'],
+          Url::fromRoute(
+            'entity.' . $entity_type_id . '.edit_form',
+            [
+              $entity_type_id => $issue['source_id'],
+            ]
+          )
+        );
+      }
+
       $rows[] = [
-        $issue['source_entity_type'],
-        $issue['source_id'],
+        $entity_type_id,
+        $source_id,
         $issue['field_name'],
         $issue['field_type'],
         $issue['target_type'],
@@ -87,6 +169,10 @@ class ZombieReferenceHunterController extends ControllerBase
       '#empty' => $this->t('No broken references found.'),
     ];
 
+    $build['pager'] = [
+      '#type' => 'pager',
+    ];
+
     return $build;
   }
 

src/Service/ZombieReferenceHunterQuery.php

@@ -7,13 +7,26 @@ use Drupal\Component\Plugin\Exception\PluginNotFoundException;
 use Drupal\Core\Entity\EntityFieldManagerInterface;
 use Drupal\Core\Entity\EntityTypeManagerInterface;
 use Drupal\Core\Logger\LoggerChannelInterface;
+use Drupal\Core\Cache\Cache;
+use Drupal\Core\Cache\CacheBackendInterface;
+
+class ZombieReferenceHunterQuery {
 
-class ZombieReferenceHunterQuery
-{
   /**
    * Default number of entities loaded per batch.
    */
   const BATCH_SIZE = 200;
+
+  /**
+   * Cache ID for scan results.
+   */
+  const CACHE_ID = 'zombie_reference_hunter.issues';
+
+  /**
+   * Cached scan results.
+   */
+  protected CacheBackendInterface $cache;
+
   /**
    * The entity type manager.
    *
@@ -48,11 +61,13 @@ class ZombieReferenceHunterQuery
   public function __construct(
     EntityTypeManagerInterface $entityTypeManager,
     EntityFieldManagerInterface $entityFieldManager,
-    LoggerChannelInterface $logger
+    LoggerChannelInterface $logger,
+    CacheBackendInterface $cache
   ) {
     $this->entityTypeManager = $entityTypeManager;
     $this->entityFieldManager = $entityFieldManager;
     $this->logger = $logger;
+    $this->cache = $cache;
   }
 
   /**
@@ -187,4 +202,47 @@ class ZombieReferenceHunterQuery
 
     return $issues;
   }
+
+  /**
+   * Gets the current report results.
+   *
+   * Uses cached results when available. If there is no cached scan,
+   * a new scan is performed automatically.
+   *
+   * @return array
+   *   Broken reference records.
+   */
+  public function getIssues(): array {
+    if ($cache = $this->cache->get(self::CACHE_ID)) {
+      return $cache->data;
+    }
+
+    return $this->rebuildCache();
+  }
+
+  /**
+   * Performs a fresh scan and caches the results.
+   *
+   * @return array
+   *   Broken reference records.
+   */
+  public function rebuildCache(): array {
+    $issues = $this->scan();
+
+    $this->cache->set(
+      self::CACHE_ID,
+      $issues,
+      Cache::PERMANENT
+    );
+
+    return $issues;
+  }
+
+  /**
+   * Clears the cached scan.
+   */
+  public function clearCache(): void {
+    $this->cache->delete(self::CACHE_ID);
+  }
+
 }

zombie_reference_hunter.links.menu.yml

@@ -0,0 +1,6 @@
+zombie_reference_hunter.prepare:
+  title: 'Zombie Reference Hunter'
+  description: 'Find and repair zombie entity references.'
+  route_name: zombie_reference_hunter.prepare
+  parent: system.admin_reports
+  weight: 10

zombie_reference_hunter.routing.yml

@@ -1,6 +1,7 @@
 zombie_reference_hunter.prepare:
-  path: '/admin/zombies'
+  path: '/admin/reports/zombies'
   defaults:
     _controller: '\Drupal\zombie_reference_hunter\Controller\ZombieReferenceHunterController::view'
+    _title: 'Zombie Reference Hunter'
   requirements:
     _custom_access: '\Drupal\zombie_reference_hunter\Controller\ZombieReferenceHunterController::access'

zombie_reference_hunter.services.yml

@@ -6,6 +6,7 @@ services:
       - '@entity_type.manager'
       - '@entity_field.manager'
       - '@logger.channel.zombie_reference_hunter'
+      - '@cache.data'
 
   logger.channel.zombie_reference_hunter:
     parent: logger.channel_base