Issue #3491782 by phenaproxima, penyaskito, thejimbirch, gambry, amateescu,...

Issue #3491782 by phenaproxima, penyaskito, thejimbirch, gambry, amateescu, alexpott: When applying a recipe, we need to trigger an event pre importing content

(cherry picked from commit 51ae0389)

core/lib/Drupal/Core/DefaultContent/Importer.php

@@ -18,6 +18,7 @@
 use Drupal\user\EntityOwnerInterface;
 use Psr\Log\LoggerAwareInterface;
 use Psr\Log\LoggerAwareTrait;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * A service for handling import of content.
@@ -45,6 +46,7 @@ public function __construct(
     private readonly FileSystemInterface $fileSystem,
     private readonly LanguageManagerInterface $languageManager,
     private readonly EntityRepositoryInterface $entityRepository,
+    private readonly EventDispatcherInterface $eventDispatcher,
   ) {}
 
   /**
@@ -70,6 +72,9 @@ public function importContent(Finder $content, Existing $existing = Existing::Er
       return;
     }
 
+    $event = new PreImportEvent($content, $existing);
+    $skip = $this->eventDispatcher->dispatch($event)->getSkipList();
+
     $account = $this->accountSwitcher->switchToAdministrator();
 
     try {
@@ -80,6 +85,19 @@ public function importContent(Finder $content, Existing $existing = Existing::Er
         assert(is_string($entity_type_id));
         assert(is_string($path));
 
+        // The event subscribers asked to skip importing this entity. If they
+        // explained why, log that.
+        if (array_key_exists($uuid, $skip)) {
+          if ($skip[$uuid]) {
+            $this->logger?->info('Skipped importing @entity_type @uuid because: %reason', [
+              '@entity_type' => $entity_type_id,
+              '@uuid' => $uuid,
+              '%reason' => $skip[$uuid],
+            ]);
+          }
+          continue;
+        }
+
         $entity_type = $this->entityTypeManager->getDefinition($entity_type_id);
         /** @var \Drupal\Core\Entity\EntityTypeInterface $entity_type */
         if (!$entity_type->entityClassImplements(ContentEntityInterface::class)) {

core/lib/Drupal/Core/DefaultContent/PreImportEvent.php

+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\Core\DefaultContent;
+
+use Symfony\Contracts\EventDispatcher\Event;
+
+/**
+ * Event dispatched before default content is imported.
+ *
+ * Subscribers to this event should avoid modifying content, because it is
+ * probably about to change again. This event is best used for tasks like
+ * notifications, logging, or updating a value in state. It can also be used
+ * to skip importing certain entities, identified by their UUID.
+ */
+final class PreImportEvent extends Event {
+
+  /**
+   * Entity UUIDs that should not be imported.
+   *
+   * @var string[]
+   */
+  private array $skip = [];
+
+  /**
+   * Constructs a PreImportEvent object.
+   *
+   * @param \Drupal\Core\DefaultContent\Finder $finder
+   *   The content finder, which has information on the entities to create
+   *   in the necessary dependency order.
+   * @param \Drupal\Core\DefaultContent\Existing $existing
+   *   What the importer will do when importing an entity that already exists.
+   */
+  public function __construct(
+    public readonly Finder $finder,
+    public readonly Existing $existing,
+  ) {}
+
+  /**
+   * Adds an entity UUID to the skip list.
+   *
+   * @param string $uuid
+   *   The UUID of an entity that should not be imported.
+   * @param string|\Stringable|null $reason
+   *   (optional) A reason why the entity is being skipped. Defaults to NULL.
+   *
+   * @throws \InvalidArgumentException
+   *   If the given UUID is not one of the ones being imported.
+   */
+  public function skip(string $uuid, string|\Stringable|null $reason = NULL): void {
+    if (array_key_exists($uuid, $this->finder->data)) {
+      $this->skip[$uuid] = $reason;
+    }
+    else {
+      throw new \InvalidArgumentException("Content entity '$uuid' cannot be skipped, because it is not one of the entities being imported.");
+    }
+  }
+
+  /**
+   * Returns the list of entity UUIDs that should not be imported.
+   *
+   * @return string|\Stringable|null[]
+   *   An array whose keys are the UUIDs of the entities that should not be
+   *   imported, and the values are either a short explanation of why that
+   *   entity was skipped, or NULL if no explanation was given.
+   */
+  public function getSkipList(): array {
+    return $this->skip;
+  }
+
+}

core/tests/Drupal/FunctionalTests/DefaultContent/ContentImportTest.php

@@ -8,6 +8,7 @@
 use Drupal\block_content\BlockContentInterface;
 use Drupal\block_content\Entity\BlockContentType;
 use Drupal\Component\Serialization\Yaml;
+use Drupal\Core\DefaultContent\PreImportEvent;
 use Drupal\Core\DefaultContent\Existing;
 use Drupal\Core\DefaultContent\Finder;
 use Drupal\Core\DefaultContent\Importer;
@@ -33,6 +34,7 @@
 use Drupal\Tests\media\Traits\MediaTypeCreationTrait;
 use Drupal\Tests\taxonomy\Traits\TaxonomyTestTrait;
 use Psr\Log\LogLevel;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
 
 /**
  * @covers \Drupal\Core\DefaultContent\Importer
@@ -277,7 +279,50 @@ private function assertContentWasImported(): void {
     $this->assertInstanceOf(Section::class, $section);
     $this->assertCount(2, $section->getComponents());
     $this->assertSame('system_powered_by_block', $section->getComponent('03b45f14-cf74-469a-8398-edf3383ce7fa')->getPluginId());
+  }
+
+  /**
+   * Tests that the pre-import event allows skipping certain entities.
+   */
+  public function testPreImportEvent(): void {
+    $invalid_uuid_detected = FALSE;
+
+    $listener = function (PreImportEvent $event) use (&$invalid_uuid_detected): void {
+      $event->skip('3434bd5a-d2cd-4f26-bf79-a7f6b951a21b', 'Decided not to!');
+      try {
+        $event->skip('not-a-thing');
+      }
+      catch (\InvalidArgumentException) {
+        $invalid_uuid_detected = TRUE;
+      }
+    };
+    \Drupal::service(EventDispatcherInterface::class)
+      ->addListener(PreImportEvent::class, $listener);
 
+    $finder = new Finder($this->contentDir);
+    $this->assertSame('menu_link_content', $finder->data['3434bd5a-d2cd-4f26-bf79-a7f6b951a21b']['_meta']['entity_type']);
+
+    /** @var \Drupal\Core\DefaultContent\Importer $importer */
+    $importer = \Drupal::service(Importer::class);
+    $logger = new TestLogger();
+    $importer->setLogger($logger);
+    $importer->importContent($finder, Existing::Error);
+
+    // The entity we skipped should not be here, and the reason why should have
+    // been logged.
+    $menu_link = \Drupal::service(EntityRepositoryInterface::class)
+      ->loadEntityByUuid('menu_link_content', '3434bd5a-d2cd-4f26-bf79-a7f6b951a21b');
+    $this->assertNull($menu_link);
+    $this->assertTrue($logger->hasInfo([
+      'message' => 'Skipped importing @entity_type @uuid because: %reason',
+      'context' => [
+        '@entity_type' => 'menu_link_content',
+        '@uuid' => '3434bd5a-d2cd-4f26-bf79-a7f6b951a21b',
+        '%reason' => 'Decided not to!',
+      ],
+    ]));
+    // We should have caught an exception for trying to skip an invalid UUID.
+    $this->assertTrue($invalid_uuid_detected);
   }
 
 }