modules/next_graphql/next_graphql.info.yml

+name: "Next.js GraphQL"
+type: module
+description: "GraphQL for Next.js"
+core_version_requirement: ^9
+package: Web services
+dependencies:
+  - graphql:graphql
+  - graphql_compose:graphql_compose
+  - next:next

src/Entity/NextSite.php

@@ -194,7 +194,9 @@ class NextSite extends ConfigEntityBase implements NextSiteInterface {
         ->getId();
     }
 
-    $query['resourceVersion'] = $resource_version;
+    if ($resource_version) {
+      $query['resourceVersion'] = $resource_version;
+    }
 
     $preview_url->setOption('query', $query);
 

tests/src/Kernel/Entity/NextSiteTest.php

+<?php
+
+namespace Drupal\Tests\next\Kernel\Entity;
+
+use Drupal\Component\Serialization\Json;
+use Drupal\KernelTests\KernelTestBase;
+use Drupal\next\Controller\NextPreviewUrlController;
+use Drupal\next\Entity\NextSite;
+use Drupal\Tests\node\Traits\NodeCreationTrait;
+use Drupal\Tests\user\Traits\UserCreationTrait;
+use Drupal\user\Entity\User;
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Tests the NextSite entity.
+ *
+ * @coversDefaultClass \Drupal\next\Entity\NextSite
+ *
+ * @group next
+ */
+class NextSiteTest extends KernelTestBase {
+
+  use NodeCreationTrait, UserCreationTrait;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected static $modules = ['filter', 'next', 'node', 'system', 'user'];
+
+  /**
+   * The next_site entity.
+   *
+   * @var \Drupal\next\Entity\NextSiteInterface
+   */
+  protected $nextSite;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp(): void {
+    parent::setUp();
+
+    $this->installEntitySchema('node');
+    $this->installEntitySchema('user');
+    $this->installConfig(['filter', 'next']);
+    $this->installSchema('system', ['sequences']);
+    $this->installSchema('node', ['node_access']);
+
+    $this->nextSite = NextSite::create([
+      'label' => 'Blog',
+      'id' => 'blog',
+      'base_url' => 'https://blog.com',
+      'preview_url' => 'https://blog.com/api/preview',
+      'preview_secret' => 'one'
+    ]);
+    $this->nextSite->save();
+
+    $this->setUpCurrentUser();
+  }
+
+  /**
+   * @covers ::getPreviewUrlForEntity
+   */
+  public function testGetPreviewUrlForEntity() {
+    $user = $this->createUser(['access content']);
+    $this->setCurrentUser($user);
+
+    // User entity type is not versionable.
+    // No resourceVersion in the query.
+    $preview_url = $this->nextSite->getPreviewUrlForEntity(User::load(1));
+    $query = $preview_url->getOption('query');
+    $this->assertNotContains('resourceVersion', array_keys($query));
+
+    // Node entity type is versionable.
+    // Expect a resourceVersion.
+    $node = $this->createNode();
+    $preview_url = $this->nextSite->getPreviewUrlForEntity($node);
+    $query = $preview_url->getOption('query');
+    $this->assertSame('rel:latest-version', $query['resourceVersion']);
+  }
+
+}