Issue #3267603 by phenaproxima: Prevent updates in a multisite

automatic_updates.services.yml

@@ -85,6 +85,12 @@ services:
       - '@package_manager.validator.file_system'
     tags:
       - { name: event_subscriber }
+  automatic_updates.validator.multisite:
+    class: Drupal\automatic_updates\Validator\PackageManagerReadinessCheck
+    arguments:
+      - '@package_manager.validator.multisite'
+    tags:
+      - { name: event_subscriber }
   automatic_updates.cron_frequency_validator:
     class: Drupal\automatic_updates\Validator\CronFrequencyValidator
     arguments:

package_manager/package_manager.services.yml

@@ -120,6 +120,13 @@ services:
       - '@string_translation'
     tags:
       - { name: event_subscriber }
+  package_manager.validator.multisite:
+    class: Drupal\package_manager\Validator\MultisiteValidator
+    arguments:
+      - '@package_manager.path_locator'
+      - '@string_translation'
+    tags:
+      - { name: event_subscriber }
   package_manager.excluded_paths_subscriber:
     class: Drupal\package_manager\EventSubscriber\ExcludedPathsSubscriber
     arguments:

package_manager/src/Validator/MultisiteValidator.php

+<?php
+
+namespace Drupal\package_manager\Validator;
+
+use Drupal\Core\StringTranslation\StringTranslationTrait;
+use Drupal\Core\StringTranslation\TranslationInterface;
+use Drupal\package_manager\Event\PreCreateEvent;
+use Drupal\package_manager\Event\PreOperationStageEvent;
+use Drupal\package_manager\PathLocator;
+
+/**
+ * Checks that the current site is not part of a multisite.
+ */
+class MultisiteValidator implements PreOperationStageValidatorInterface {
+
+  use StringTranslationTrait;
+
+  /**
+   * The path locator service.
+   *
+   * @var \Drupal\package_manager\PathLocator
+   */
+  protected $pathLocator;
+
+  /**
+   * Constructs a new MultisiteValidator.
+   *
+   * @param \Drupal\package_manager\PathLocator $path_locator
+   *   The path locator service.
+   * @param \Drupal\Core\StringTranslation\TranslationInterface $translation
+   *   The string translation service.
+   */
+  public function __construct(PathLocator $path_locator, TranslationInterface $translation) {
+    $this->pathLocator = $path_locator;
+    $this->setStringTranslation($translation);
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function validateStagePreOperation(PreOperationStageEvent $event): void {
+    if ($this->isMultisite()) {
+      $event->addError([
+        $this->t('Multisites are not supported by Package Manager.'),
+      ]);
+    }
+  }
+
+  /**
+   * Detects if the current site is part of a multisite.
+   *
+   * @return bool
+   *   TRUE if the current site is part of a multisite, otherwise FALSE.
+   *
+   * @todo Make this smarter in https://www.drupal.org/node/3267646.
+   */
+  protected function isMultisite(): bool {
+    $web_root = $this->pathLocator->getWebRoot();
+    if ($web_root) {
+      $web_root .= '/';
+    }
+    return file_exists($this->pathLocator->getProjectRoot() . '/' . $web_root . 'sites/sites.php');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function getSubscribedEvents() {
+    return [
+      PreCreateEvent::class => 'validateStagePreOperation',
+    ];
+  }
+
+}

package_manager/tests/src/Kernel/MultisiteValidatorTest.php

+<?php
+
+namespace Drupal\Tests\package_manager\Kernel;
+
+use Drupal\package_manager\Event\PreCreateEvent;
+use Drupal\package_manager\ValidationResult;
+
+/**
+ * @covers \Drupal\package_manager\Validator\MultisiteValidator
+ *
+ * @group package_manager
+ */
+class MultisiteValidatorTest extends PackageManagerKernelTestBase {
+
+  /**
+   * Data provider for ::testMultisite().
+   *
+   * @return array[]
+   *   Sets of arguments to pass to the test method.
+   */
+  public function providerMultisite(): array {
+    return [
+      'multisite' => [
+        TRUE,
+        [
+          ValidationResult::createError([
+            'Multisites are not supported by Package Manager.',
+          ]),
+        ],
+      ],
+      'not multisite' => [
+        FALSE,
+        [],
+      ],
+    ];
+  }
+
+  /**
+   * Tests that Package Manager flags an error if run in a multisite.
+   *
+   * @param bool $is_multisite
+   *   Whether the validator will be in a multisite.
+   * @param \Drupal\package_manager\ValidationResult[] $expected_results
+   *   The expected validation results.
+   *
+   * @dataProvider providerMultisite
+   */
+  public function testMultisite(bool $is_multisite, array $expected_results = []): void {
+    $this->createTestProject();
+
+    // If we should simulate a multisite, ensure there is a sites.php in the
+    // test project.
+    // @see \Drupal\package_manager\Validator\MultisiteValidator::isMultisite()
+    if ($is_multisite) {
+      $project_root = $this->container->get('package_manager.path_locator')
+        ->getProjectRoot();
+      touch($project_root . '/sites/sites.php');
+    }
+    $this->assertResults($expected_results, PreCreateEvent::class);
+  }
+
+}

tests/src/Kernel/ReadinessValidation/PackageManagerReadinessChecksTest.php

@@ -50,6 +50,7 @@ class PackageManagerReadinessChecksTest extends AutomaticUpdatesKernelTestBase {
       'Pending updates validator' => ['package_manager.validator.pending_updates'],
       'File system validator' => ['package_manager.validator.file_system'],
       'Composer settings validator' => ['package_manager.validator.composer_settings'],
+      'Multisite validator' => ['package_manager.validator.multisite'],
     ];
   }