feat(files_versions): allow to block version creation using WFE

apps/files_versions/composer/composer/autoload_classmap.php

@@ -20,13 +20,16 @@
     'OCA\\Files_Versions\\Events\\VersionCreatedEvent' => $baseDir . '/../lib/Events/VersionCreatedEvent.php',
     'OCA\\Files_Versions\\Events\\VersionRestoredEvent' => $baseDir . '/../lib/Events/VersionRestoredEvent.php',
     'OCA\\Files_Versions\\Expiration' => $baseDir . '/../lib/Expiration.php',
+    'OCA\\Files_Versions\\Listener\\CreateVersionListenerForWorkflow' => $baseDir . '/../lib/Listener/CreateVersionListenerForWorkflow.php',
     'OCA\\Files_Versions\\Listener\\FileEventsListener' => $baseDir . '/../lib/Listener/FileEventsListener.php',
     'OCA\\Files_Versions\\Listener\\LegacyRollbackListener' => $baseDir . '/../lib/Listener/LegacyRollbackListener.php',
     'OCA\\Files_Versions\\Listener\\LoadAdditionalListener' => $baseDir . '/../lib/Listener/LoadAdditionalListener.php',
     'OCA\\Files_Versions\\Listener\\LoadSidebarListener' => $baseDir . '/../lib/Listener/LoadSidebarListener.php',
+    'OCA\\Files_Versions\\Listener\\RegisterWorkflowIntegrationListener' => $baseDir . '/../lib/Listener/RegisterWorkflowIntegrationListener.php',
     'OCA\\Files_Versions\\Listener\\VersionAuthorListener' => $baseDir . '/../lib/Listener/VersionAuthorListener.php',
     'OCA\\Files_Versions\\Listener\\VersionStorageMoveListener' => $baseDir . '/../lib/Listener/VersionStorageMoveListener.php',
     'OCA\\Files_Versions\\Migration\\Version1020Date20221114144058' => $baseDir . '/../lib/Migration/Version1020Date20221114144058.php',
+    'OCA\\Files_Versions\\Operation' => $baseDir . '/../lib/Operation.php',
     'OCA\\Files_Versions\\Sabre\\Plugin' => $baseDir . '/../lib/Sabre/Plugin.php',
     'OCA\\Files_Versions\\Sabre\\RestoreFolder' => $baseDir . '/../lib/Sabre/RestoreFolder.php',
     'OCA\\Files_Versions\\Sabre\\RootCollection' => $baseDir . '/../lib/Sabre/RootCollection.php',

apps/files_versions/composer/composer/autoload_static.php

@@ -35,13 +35,16 @@ class ComposerStaticInitFiles_Versions
         'OCA\\Files_Versions\\Events\\VersionCreatedEvent' => __DIR__ . '/..' . '/../lib/Events/VersionCreatedEvent.php',
         'OCA\\Files_Versions\\Events\\VersionRestoredEvent' => __DIR__ . '/..' . '/../lib/Events/VersionRestoredEvent.php',
         'OCA\\Files_Versions\\Expiration' => __DIR__ . '/..' . '/../lib/Expiration.php',
+        'OCA\\Files_Versions\\Listener\\CreateVersionListenerForWorkflow' => __DIR__ . '/..' . '/../lib/Listener/CreateVersionListenerForWorkflow.php',
         'OCA\\Files_Versions\\Listener\\FileEventsListener' => __DIR__ . '/..' . '/../lib/Listener/FileEventsListener.php',
         'OCA\\Files_Versions\\Listener\\LegacyRollbackListener' => __DIR__ . '/..' . '/../lib/Listener/LegacyRollbackListener.php',
         'OCA\\Files_Versions\\Listener\\LoadAdditionalListener' => __DIR__ . '/..' . '/../lib/Listener/LoadAdditionalListener.php',
         'OCA\\Files_Versions\\Listener\\LoadSidebarListener' => __DIR__ . '/..' . '/../lib/Listener/LoadSidebarListener.php',
+        'OCA\\Files_Versions\\Listener\\RegisterWorkflowIntegrationListener' => __DIR__ . '/..' . '/../lib/Listener/RegisterWorkflowIntegrationListener.php',
         'OCA\\Files_Versions\\Listener\\VersionAuthorListener' => __DIR__ . '/..' . '/../lib/Listener/VersionAuthorListener.php',
         'OCA\\Files_Versions\\Listener\\VersionStorageMoveListener' => __DIR__ . '/..' . '/../lib/Listener/VersionStorageMoveListener.php',
         'OCA\\Files_Versions\\Migration\\Version1020Date20221114144058' => __DIR__ . '/..' . '/../lib/Migration/Version1020Date20221114144058.php',
+        'OCA\\Files_Versions\\Operation' => __DIR__ . '/..' . '/../lib/Operation.php',
         'OCA\\Files_Versions\\Sabre\\Plugin' => __DIR__ . '/..' . '/../lib/Sabre/Plugin.php',
         'OCA\\Files_Versions\\Sabre\\RestoreFolder' => __DIR__ . '/..' . '/../lib/Sabre/RestoreFolder.php',
         'OCA\\Files_Versions\\Sabre\\RootCollection' => __DIR__ . '/..' . '/../lib/Sabre/RootCollection.php',

apps/files_versions/lib/AppInfo/Application.php

@@ -13,11 +13,14 @@
 use OCA\Files\Event\LoadAdditionalScriptsEvent;
 use OCA\Files\Event\LoadSidebar;
 use OCA\Files_Versions\Capabilities;
+use OCA\Files_Versions\Events\CreateVersionEvent;
 use OCA\Files_Versions\Events\VersionRestoredEvent;
+use OCA\Files_Versions\Listener\CreateVersionListenerForWorkflow;
 use OCA\Files_Versions\Listener\FileEventsListener;
 use OCA\Files_Versions\Listener\LegacyRollbackListener;
 use OCA\Files_Versions\Listener\LoadAdditionalListener;
 use OCA\Files_Versions\Listener\LoadSidebarListener;
+use OCA\Files_Versions\Listener\RegisterWorkflowIntegrationListener;
 use OCA\Files_Versions\Listener\VersionAuthorListener;
 use OCA\Files_Versions\Listener\VersionStorageMoveListener;
 use OCA\Files_Versions\Versions\IVersionManager;
@@ -47,6 +50,8 @@
 use OCP\L10N\IFactory;
 use OCP\Server;
 use OCP\Share\IManager as IShareManager;
+use OCP\WorkflowEngine\Events\LoadSettingsScriptsEvent;
+use OCP\WorkflowEngine\Events\RegisterOperationsEvent;
 use Psr\Container\ContainerInterface;
 use Psr\Log\LoggerInterface;
 
@@ -110,8 +115,12 @@ public function register(IRegistrationContext $context): void {
 
 		// we add the version author listener with lower priority to make sure new versions already are created by FileEventsListener
 		$context->registerEventListener(NodeWrittenEvent::class, VersionAuthorListener::class, -1);
-
 		$context->registerEventListener(VersionRestoredEvent::class, LegacyRollbackListener::class);
+
+		// WFE integration
+		$context->registerEventListener(RegisterOperationsEvent::class, RegisterWorkflowIntegrationListener::class);
+		$context->registerEventListener(LoadSettingsScriptsEvent::class, RegisterWorkflowIntegrationListener::class);
+		$context->registerEventListener(CreateVersionEvent::class, CreateVersionListenerForWorkflow::class);
 	}
 
 	public function boot(IBootContext $context): void {

apps/files_versions/lib/BlockVersioningOperation.php

@@ -0,0 +1,95 @@
+<?php
+
+declare(strict_types=1);
+
+/*!
+ * SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OCA\Files_Versions;
+
+use OCA\Files_Versions\Events\CreateVersionEvent;
+use OCA\WorkflowEngine\Entity\File as FileEntity;
+use OCP\EventDispatcher\Event;
+use OCP\Files\Folder;
+use OCP\IL10N;
+use OCP\IURLGenerator;
+use OCP\WorkflowEngine\IComplexOperation;
+use OCP\WorkflowEngine\IManager;
+use OCP\WorkflowEngine\IRuleMatcher;
+use OCP\WorkflowEngine\ISpecificOperation;
+use Psr\Log\LoggerInterface;
+
+class BlockVersioningOperation implements ISpecificOperation, IComplexOperation {
+
+	public function __construct(
+		private readonly IL10N $l10n,
+		private readonly FileEntity $fileEntity,
+		private readonly LoggerInterface $logger,
+		private readonly IURLGenerator $urlGenerator,
+	) {
+	}
+
+	#[\Override]
+	public function getEntityId(): string {
+		return FileEntity::class;
+	}
+
+	#[\Override]
+	public function getDisplayName(): string {
+		return $this->l10n->t('Block versioning');
+	}
+
+	#[\Override]
+	public function getDescription(): string {
+		return $this->l10n->t('Automatic tag based blocking of files version creation.');
+	}
+
+	#[\Override]
+	public function getIcon(): string {
+		return $this->urlGenerator->imagePath('files_versions', 'app.svg');
+	}
+
+	#[\Override]
+	public function isAvailableForScope(int $scope): bool {
+		return $scope === IManager::SCOPE_ADMIN;
+	}
+
+	#[\Override]
+	public function validateOperation(string $name, array $checks, string $operation): void {
+		if (empty($checks)) {
+			throw new \UnexpectedValueException($this->l10n->t('No rule given'));
+		}
+	}
+
+	#[\Override]
+	public function onEvent(string $eventName, Event $event, IRuleMatcher $ruleMatcher): void {
+		if ($eventName !== CreateVersionEvent::class || !($event instanceof CreateVersionEvent)) {
+			return;
+		}
+
+		$node = $event->getNode();
+		$path = $node->getInternalPath();
+
+		$ruleMatcher->setFileInfo(
+			$node->getStorage(),
+			$path,
+			$node instanceof Folder,
+		);
+		$ruleMatcher->setEntitySubject($this->fileEntity, $node);
+		$ruleMatcher->setOperation($this);
+		$flows = $ruleMatcher->getFlows();
+
+		if ($flows !== []) {
+			$this->logger->debug('Blocking version creation due to matching workflow rules', [
+				'path' => $path,
+			]);
+			$event->disableVersions();
+		}
+	}
+
+	#[\Override]
+	public function getTriggerHint(): string {
+		return $this->l10n->t('A new version is created'); // TRANSLATORS: This will be shown as "When: " "A new version is created"
+	}
+}

apps/files_versions/lib/Listener/CreateVersionListenerForWorkflow.php

@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+/*!
+ * SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OCA\Files_Versions\Listener;
+
+use OCA\Files_Versions\BlockVersioningOperation;
+use OCA\Files_Versions\Events\CreateVersionEvent;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventListener;
+use OCP\WorkflowEngine\IManager;
+
+/** @template-implements IEventListener<CreateVersionEvent> */
+class CreateVersionListenerForWorkflow implements IEventListener {
+
+	public function __construct(
+		private IManager $manager,
+		private BlockVersioningOperation $operation,
+	) {
+	}
+
+	public function handle(Event $event): void {
+		if (!($event instanceof CreateVersionEvent)) {
+			return;
+		}
+
+		$this->operation->onEvent(
+			$event::class,
+			$event,
+			$this->manager->getRuleMatcher(),
+		);
+	}
+}

apps/files_versions/lib/Listener/RegisterWorkflowIntegrationListener.php

@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+/*!
+ * SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OCA\Files_Versions\Listener;
+
+use OCA\Files_Versions\BlockVersioningOperation;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventListener;
+use OCP\Util;
+use OCP\WorkflowEngine\Events\LoadSettingsScriptsEvent;
+use OCP\WorkflowEngine\Events\RegisterOperationsEvent;
+
+/** @template-implements IEventListener<RegisterOperationsEvent|LoadSettingsScriptsEvent> */
+class RegisterWorkflowIntegrationListener implements IEventListener {
+
+	public function __construct(
+		private readonly BlockVersioningOperation $operation,
+	) {
+	}
+
+	public function handle(Event $event): void {
+		if ($event instanceof RegisterOperationsEvent) {
+			$event->registerOperation($this->operation);
+		} elseif ($event instanceof LoadSettingsScriptsEvent) {
+			Util::addScript('files_versions', 'workflow', 'workflowengine');
+		}
+	}
+}

apps/files_versions/lib/Storage.php

@@ -205,6 +205,7 @@ public static function store($filename) {
 		}
 
 		$event = new CreateVersionEvent($file);
+		$eventDispatcher->dispatchTyped($event);
 		$eventDispatcher->dispatch('OCA\Files_Versions::createVersion', $event);
 		if ($event->shouldCreateVersion() === false) {
 			return false;

apps/files_versions/src/workflow.ts

@@ -0,0 +1,12 @@
+/*!
+ * SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+window.addEventListener('DOMContentLoaded', () => {
+	globalThis.OCA.WorkflowEngine.registerOperator({
+		id: 'OCA\\Files_Versions\\BlockVersioningOperation',
+		color: '#ff5900',
+		operation: 'deny',
+	})
+})

build/frontend/vite.config.ts

@@ -45,6 +45,7 @@ const modules = {
 	},
 	files_versions: {
 		'sidebar-tab': resolve(import.meta.dirname, 'apps/files_versions/src', 'sidebar_tab.ts'),
+		workflow: resolve(import.meta.dirname, 'apps/files_versions/src', 'workflow.ts'),
 	},
 	oauth2: {
 		'settings-admin': resolve(import.meta.dirname, 'apps/oauth2/src', 'settings-admin.ts'),