Merge pull request #40326 from nextcloud/enh/text-to-image-api

Implement TextToImage OCP API

9 files changed, 751 insertions, 4 deletions

diff --git a/lib/private/AppFramework/Bootstrap/RegistrationContext.php b/lib/private/AppFramework/Bootstrap/RegistrationContext.php
index d4588527006..5ff2dcd7969 100644
--- a/lib/private/AppFramework/Bootstrap/RegistrationContext.php
+++ b/lib/private/AppFramework/Bootstrap/RegistrationContext.php
@@ -138,6 +138,12 @@ class RegistrationContext {
 	/** @var ServiceRegistration<IReferenceProvider>[] */
 	private array $referenceProviders = [];
 
+	/** @var ServiceRegistration<\OCP\TextToImage\IProvider>[] */
+	private $textToImageProviders = [];
+
+
+
+
 	/** @var ParameterRegistration[] */
 	private $sensitiveMethods = [];
 
@@ -273,6 +279,13 @@ class RegistrationContext {
 				);
 			}
 
+			public function registerTextToImageProvider(string $providerClass): void {
+				$this->context->registerTextToImageProvider(
+					$this->appId,
+					$providerClass
+				);
+			}
+
 			public function registerTemplateProvider(string $providerClass): void {
 				$this->context->registerTemplateProvider(
 					$this->appId,
@@ -450,6 +463,10 @@ class RegistrationContext {
 		$this->textProcessingProviders[] = new ServiceRegistration($appId, $class);
 	}
 
+	public function registerTextToImageProvider(string $appId, string $class): void {
+		$this->textToImageProviders[] = new ServiceRegistration($appId, $class);
+	}
+
 	public function registerTemplateProvider(string $appId, string $class): void {
 		$this->templateProviders[] = new ServiceRegistration($appId, $class);
 	}
@@ -740,6 +757,13 @@ class RegistrationContext {
 	}
 
 	/**
+	 * @return ServiceRegistration<\OCP\TextToImage\IProvider>[]
+	 */
+	public function getTextToImageProviders(): array {
+		return $this->textToImageProviders;
+	}
+
+	/**
 	 * @return ServiceRegistration<ICustomTemplateProvider>[]
 	 */
 	public function getTemplateProviders(): array {
diff --git a/lib/private/Files/Node/Folder.php b/lib/private/Files/Node/Folder.php
index ccd10da9d0c..c7462572fed 100644
--- a/lib/private/Files/Node/Folder.php
+++ b/lib/private/Files/Node/Folder.php
@@ -177,7 +177,7 @@ class Folder extends Node implements \OCP\Files\Folder {
 	 * @throws \OCP\Files\NotPermittedException
 	 */
 	public function newFile($path, $content = null) {
-		if (empty($path)) {
+		if ($path === '') {
 			throw new NotPermittedException('Could not create as provided path is empty');
 		}
 		if ($this->checkPermissions(\OCP\Constants::PERMISSION_CREATE)) {
diff --git a/lib/private/Repair/AddRemoveOldTasksBackgroundJob.php b/lib/private/Repair/AddRemoveOldTasksBackgroundJob.php
index 94ae39f2183..00badbb726d 100644
--- a/lib/private/Repair/AddRemoveOldTasksBackgroundJob.php
+++ b/lib/private/Repair/AddRemoveOldTasksBackgroundJob.php
@@ -25,7 +25,8 @@ declare(strict_types=1);
  */
 namespace OC\Repair;
 
-use OC\TextProcessing\RemoveOldTasksBackgroundJob;
+use OC\TextProcessing\RemoveOldTasksBackgroundJob as RemoveOldTextProcessingTasksBackgroundJob;
+use OC\TextToImage\RemoveOldTasksBackgroundJob as RemoveOldTextToImageTasksBackgroundJob;
 use OCP\BackgroundJob\IJobList;
 use OCP\Migration\IOutput;
 use OCP\Migration\IRepairStep;
@@ -38,10 +39,11 @@ class AddRemoveOldTasksBackgroundJob implements IRepairStep {
 	}
 
 	public function getName(): string {
-		return 'Add language model tasks cleanup job';
+		return 'Add AI tasks cleanup job';
 	}
 
 	public function run(IOutput $output) {
-		$this->jobList->add(RemoveOldTasksBackgroundJob::class);
+		$this->jobList->add(RemoveOldTextProcessingTasksBackgroundJob::class);
+		$this->jobList->add(RemoveOldTextToImageTasksBackgroundJob::class);
 	}
 }
diff --git a/lib/private/Server.php b/lib/private/Server.php
index 37b7669f624..77791c49e8b 100644
--- a/lib/private/Server.php
+++ b/lib/private/Server.php
@@ -1428,6 +1428,8 @@ class Server extends ServerContainer implements IServerContainer {
 
 		$this->registerAlias(\OCP\TextProcessing\IManager::class, \OC\TextProcessing\Manager::class);
 
+		$this->registerAlias(\OCP\TextToImage\IManager::class, \OC\TextToImage\Manager::class);
+
 		$this->registerAlias(ILimiter::class, Limiter::class);
 
 		$this->registerAlias(IPhoneNumberUtil::class, PhoneNumberUtil::class);
diff --git a/lib/private/TextToImage/Db/Task.php b/lib/private/TextToImage/Db/Task.php
new file mode 100644
index 00000000000..96dd6e4e165
--- /dev/null
+++ b/lib/private/TextToImage/Db/Task.php
@@ -0,0 +1,117 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2023 Marcel Klehr <mklehr@gmx.net>
+ *
+ * @author Marcel Klehr <mklehr@gmx.net>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+namespace OC\TextToImage\Db;
+
+use DateTime;
+use OCP\AppFramework\Db\Entity;
+use OCP\AppFramework\Utility\ITimeFactory;
+use OCP\TextToImage\Task as OCPTask;
+
+/**
+ * @method setLastUpdated(DateTime $lastUpdated)
+ * @method DateTime getLastUpdated()
+ * @method setInput(string $type)
+ * @method string getInput()
+ * @method setResultPath(string $resultPath)
+ * @method string getResultPath()
+ * @method setStatus(int $type)
+ * @method int getStatus()
+ * @method setUserId(?string $userId)
+ * @method string|null getUserId()
+ * @method setAppId(string $type)
+ * @method string getAppId()
+ * @method setIdentifier(string $identifier)
+ * @method string|null getIdentifier()
+ * @method setNumberOfImages(int $numberOfImages)
+ * @method int getNumberOfImages()
+ * @method setCompletionExpectedAt(DateTime $at)
+ * @method DateTime getCompletionExpectedAt()
+ */
+class Task extends Entity {
+	protected $lastUpdated;
+	protected $type;
+	protected $input;
+	protected $status;
+	protected $userId;
+	protected $appId;
+	protected $identifier;
+	protected $numberOfImages;
+	protected $completionExpectedAt;
+
+	/**
+	 * @var string[]
+	 */
+	public static array $columns = ['id', 'last_updated', 'input', 'status', 'user_id', 'app_id', 'identifier', 'number_of_images', 'completion_expected_at'];
+
+	/**
+	 * @var string[]
+	 */
+	public static array $fields = ['id', 'lastUpdated', 'input', 'status', 'userId', 'appId', 'identifier', 'numberOfImages', 'completionExpectedAt'];
+
+
+	public function __construct() {
+		// add types in constructor
+		$this->addType('id', 'integer');
+		$this->addType('lastUpdated', 'datetime');
+		$this->addType('input', 'string');
+		$this->addType('status', 'integer');
+		$this->addType('userId', 'string');
+		$this->addType('appId', 'string');
+		$this->addType('identifier', 'string');
+		$this->addType('numberOfImages', 'integer');
+		$this->addType('completionExpectedAt', 'datetime');
+	}
+
+	public function toRow(): array {
+		return array_combine(self::$columns, array_map(function ($field) {
+			return $this->{'get'.ucfirst($field)}();
+		}, self::$fields));
+	}
+
+	public static function fromPublicTask(OCPTask $task): Task {
+		/** @var Task $dbTask */
+		$dbTask = Task::fromParams([
+			'id' => $task->getId(),
+			'lastUpdated' => \OCP\Server::get(ITimeFactory::class)->getDateTime(),
+			'status' => $task->getStatus(),
+			'numberOfImages' => $task->getNumberOfImages(),
+			'input' => $task->getInput(),
+			'userId' => $task->getUserId(),
+			'appId' => $task->getAppId(),
+			'identifier' => $task->getIdentifier(),
+			'completionExpectedAt' => $task->getCompletionExpectedAt(),
+		]);
+		return $dbTask;
+	}
+
+	public function toPublicTask(): OCPTask {
+		$task = new OCPTask($this->getInput(), $this->getAppId(), $this->getNumberOfImages(), $this->getuserId(), $this->getIdentifier());
+		$task->setId($this->getId());
+		$task->setStatus($this->getStatus());
+		$task->setCompletionExpectedAt($this->getCompletionExpectedAt());
+		return $task;
+	}
+}
diff --git a/lib/private/TextToImage/Db/TaskMapper.php b/lib/private/TextToImage/Db/TaskMapper.php
new file mode 100644
index 00000000000..68fdd8f40de
--- /dev/null
+++ b/lib/private/TextToImage/Db/TaskMapper.php
@@ -0,0 +1,127 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2023 Marcel Klehr <mklehr@gmx.net>
+ *
+ * @author Marcel Klehr <mklehr@gmx.net>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+namespace OC\TextToImage\Db;
+
+use OCP\AppFramework\Db\DoesNotExistException;
+use OCP\AppFramework\Db\Entity;
+use OCP\AppFramework\Db\MultipleObjectsReturnedException;
+use OCP\AppFramework\Db\QBMapper;
+use OCP\AppFramework\Utility\ITimeFactory;
+use OCP\DB\Exception;
+use OCP\DB\QueryBuilder\IQueryBuilder;
+use OCP\IDBConnection;
+
+/**
+ * @extends QBMapper<Task>
+ */
+class TaskMapper extends QBMapper {
+	public function __construct(
+		IDBConnection $db,
+		private ITimeFactory $timeFactory,
+	) {
+		parent::__construct($db, 'text2image_tasks', Task::class);
+	}
+
+	/**
+	 * @param int $id
+	 * @return Task
+	 * @throws Exception
+	 * @throws DoesNotExistException
+	 * @throws MultipleObjectsReturnedException
+	 */
+	public function find(int $id): Task {
+		$qb = $this->db->getQueryBuilder();
+		$qb->select(Task::$columns)
+			->from($this->tableName)
+			->where($qb->expr()->eq('id', $qb->createPositionalParameter($id)));
+		return $this->findEntity($qb);
+	}
+
+	/**
+	 * @param int $id
+	 * @param string|null $userId
+	 * @return Task
+	 * @throws DoesNotExistException
+	 * @throws Exception
+	 * @throws MultipleObjectsReturnedException
+	 */
+	public function findByIdAndUser(int $id, ?string $userId): Task {
+		$qb = $this->db->getQueryBuilder();
+		$qb->select(Task::$columns)
+			->from($this->tableName)
+			->where($qb->expr()->eq('id', $qb->createPositionalParameter($id)));
+		if ($userId === null) {
+			$qb->andWhere($qb->expr()->isNull('user_id'));
+		} else {
+			$qb->andWhere($qb->expr()->eq('user_id', $qb->createPositionalParameter($userId)));
+		}
+		return $this->findEntity($qb);
+	}
+
+	/**
+	 * @param string $userId
+	 * @param string $appId
+	 * @param string|null $identifier
+	 * @return array
+	 * @throws Exception
+	 */
+	public function findUserTasksByApp(?string $userId, string $appId, ?string $identifier = null): array {
+		$qb = $this->db->getQueryBuilder();
+		$qb->select(Task::$columns)
+			->from($this->tableName)
+			->where($qb->expr()->eq('user_id', $qb->createPositionalParameter($userId)))
+			->andWhere($qb->expr()->eq('app_id', $qb->createPositionalParameter($appId)));
+		if ($identifier !== null) {
+			$qb->andWhere($qb->expr()->eq('identifier', $qb->createPositionalParameter($identifier)));
+		}
+		return $this->findEntities($qb);
+	}
+
+	/**
+	 * @param int $timeout
+	 * @return Task[] the deleted tasks
+	 * @throws Exception
+	 */
+	public function deleteOlderThan(int $timeout): array {
+		$datetime = $this->timeFactory->getDateTime();
+		$datetime->sub(new \DateInterval('PT'.$timeout.'S'));
+		$qb = $this->db->getQueryBuilder();
+		$qb->select('*')
+			->from($this->tableName)
+			->where($qb->expr()->lt('last_updated', $qb->createPositionalParameter($datetime, IQueryBuilder::PARAM_DATE)));
+		$deletedTasks = $this->findEntities($qb);
+		$qb = $this->db->getQueryBuilder();
+		$qb->delete($this->tableName)
+			->where($qb->expr()->lt('last_updated', $qb->createPositionalParameter($datetime, IQueryBuilder::PARAM_DATE)));
+		$qb->executeStatement();
+		return $deletedTasks;
+	}
+
+	public function update(Entity $entity): Entity {
+		$entity->setLastUpdated($this->timeFactory->getDateTime());
+		return parent::update($entity);
+	}
+}
diff --git a/lib/private/TextToImage/Manager.php b/lib/private/TextToImage/Manager.php
new file mode 100644
index 00000000000..1553fed7545
--- /dev/null
+++ b/lib/private/TextToImage/Manager.php
@@ -0,0 +1,334 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2023 Marcel Klehr <mklehr@gmx.net>
+ *
+ * @author Marcel Klehr <mklehr@gmx.net>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+namespace OC\TextToImage;
+
+use OC\AppFramework\Bootstrap\Coordinator;
+use OC\TextToImage\Db\Task as DbTask;
+use OCP\Files\AppData\IAppDataFactory;
+use OCP\Files\IAppData;
+use OCP\Files\NotFoundException;
+use OCP\Files\NotPermittedException;
+use OCP\IConfig;
+use OCP\TextToImage\Exception\TaskFailureException;
+use OCP\TextToImage\Exception\TaskNotFoundException;
+use OCP\TextToImage\IManager;
+use OCP\TextToImage\Task;
+use OC\TextToImage\Db\TaskMapper;
+use OCP\AppFramework\Db\DoesNotExistException;
+use OCP\AppFramework\Db\MultipleObjectsReturnedException;
+use OCP\BackgroundJob\IJobList;
+use OCP\DB\Exception;
+use OCP\IServerContainer;
+use OCP\TextToImage\IProvider;
+use OCP\PreConditionNotMetException;
+use Psr\Log\LoggerInterface;
+use RuntimeException;
+use Throwable;
+
+class Manager implements IManager {
+	/** @var ?IProvider[] */
+	private ?array $providers = null;
+	private IAppData $appData;
+
+	public function __construct(
+		private IServerContainer $serverContainer,
+		private Coordinator $coordinator,
+		private LoggerInterface $logger,
+		private IJobList $jobList,
+		private TaskMapper $taskMapper,
+		private IConfig $config,
+		IAppDataFactory $appDataFactory,
+	) {
+		$this->appData = $appDataFactory->get('core');
+	}
+
+	/**
+	 * @inerhitDocs
+	 */
+	public function getProviders(): array {
+		$context = $this->coordinator->getRegistrationContext();
+		if ($context === null) {
+			return [];
+		}
+
+		if ($this->providers !== null) {
+			return $this->providers;
+		}
+
+		$this->providers = [];
+
+		foreach ($context->getTextToImageProviders() as $providerServiceRegistration) {
+			$class = $providerServiceRegistration->getService();
+			try {
+				$this->providers[$class] = $this->serverContainer->get($class);
+			} catch (Throwable $e) {
+				$this->logger->error('Failed to load Text to image provider ' . $class, [
+					'exception' => $e,
+				]);
+			}
+		}
+
+		return $this->providers;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function hasProviders(): bool {
+		$context = $this->coordinator->getRegistrationContext();
+		if ($context === null) {
+			return false;
+		}
+		return count($context->getTextToImageProviders()) > 0;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function runTask(Task $task): void {
+		$this->logger->debug('Running TextToImage Task');
+		if (!$this->hasProviders()) {
+			throw new PreConditionNotMetException('No text to image provider is installed that can handle this task');
+		}
+		$providers = $this->getProviders();
+
+		$json = $this->config->getAppValue('core', 'ai.text2image_provider', '');
+		if ($json !== '') {
+			try {
+				$className = json_decode($json, true, 512, JSON_THROW_ON_ERROR);
+				$provider = current(array_filter($providers, fn ($provider) => $provider::class === $className));
+				if ($provider !== false) {
+					$providers = [$provider];
+				}
+			} catch (\JsonException $e) {
+				$this->logger->warning('Failed to decode Text2Image setting `ai.text2image_provider`', ['exception' => $e]);
+			}
+		}
+
+		foreach ($providers as $provider) {
+			$this->logger->debug('Trying to run Text2Image provider '.$provider::class);
+			try {
+				$task->setStatus(Task::STATUS_RUNNING);
+				if ($task->getId() === null) {
+					$this->logger->debug('Inserting Text2Image task into DB');
+					$taskEntity = $this->taskMapper->insert(DbTask::fromPublicTask($task));
+					$task->setId($taskEntity->getId());
+				} else {
+					$this->logger->debug('Updating Text2Image task in DB');
+					$this->taskMapper->update(DbTask::fromPublicTask($task));
+				}
+				try {
+					$folder = $this->appData->getFolder('text2image');
+				} catch(NotFoundException) {
+					$this->logger->debug('Creating folder in appdata for Text2Image results');
+					$folder = $this->appData->newFolder('text2image');
+				}
+				try {
+					$folder = $folder->getFolder((string) $task->getId());
+				} catch(NotFoundException) {
+					$this->logger->debug('Creating new folder in appdata Text2Image results folder');
+					$folder = $folder->newFolder((string) $task->getId());
+				}
+				$this->logger->debug('Creating result files for Text2Image task');
+				$resources = [];
+				$files = [];
+				for ($i = 0; $i < $task->getNumberOfImages(); $i++) {
+					$file = $folder->newFile((string) $i);
+					$files[] = $file;
+					$resource = $file->write();
+					if ($resource !== false && $resource !== true && is_resource($resource)) {
+						$resources[] = $resource;
+					} else {
+						throw new RuntimeException('Text2Image generation using provider "' . $provider->getName() . '" failed: Couldn\'t open file to write.');
+					}
+				}
+				$this->logger->debug('Calling Text2Image provider\'s generate method');
+				$provider->generate($task->getInput(), $resources);
+				for ($i = 0; $i < $task->getNumberOfImages(); $i++) {
+					if (is_resource($resources[$i])) {
+						// If $resource hasn't been closed yet, we'll do that here
+						fclose($resources[$i]);
+					}
+				}
+				$task->setStatus(Task::STATUS_SUCCESSFUL);
+				$this->logger->debug('Updating Text2Image task in DB');
+				$this->taskMapper->update(DbTask::fromPublicTask($task));
+				return;
+			} catch (\RuntimeException|\Throwable $e) {
+				for ($i = 0; $i < $task->getNumberOfImages(); $i++) {
+					if (isset($files, $files[$i])) {
+						try {
+							$files[$i]->delete();
+						} catch(NotPermittedException $e) {
+							$this->logger->warning('Failed to clean up Text2Image result file after error', ['exception' => $e]);
+						}
+					}
+				}
+
+				$this->logger->info('Text2Image generation using provider "' . $provider->getName() . '" failed', ['exception' => $e]);
+				$task->setStatus(Task::STATUS_FAILED);
+				try {
+					$this->taskMapper->update(DbTask::fromPublicTask($task));
+				} catch (Exception $e) {
+					$this->logger->warning('Failed to update database after Text2Image error', ['exception' => $e]);
+				}
+				throw new TaskFailureException('Text2Image generation using provider "' . $provider->getName() . '" failed: ' . $e->getMessage(), 0, $e);
+			}
+		}
+
+		$task->setStatus(Task::STATUS_FAILED);
+		try {
+			$this->taskMapper->update(DbTask::fromPublicTask($task));
+		} catch (Exception $e) {
+			$this->logger->warning('Failed to update database after Text2Image error', ['exception' => $e]);
+		}
+		throw new TaskFailureException('Could not run task');
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function scheduleTask(Task $task): void {
+		if (!$this->hasProviders()) {
+			throw new PreConditionNotMetException('No text to image provider is installed that can handle this task');
+		}
+		$this->logger->debug('Scheduling Text2Image Task');
+		$task->setStatus(Task::STATUS_SCHEDULED);
+		$taskEntity = DbTask::fromPublicTask($task);
+		$this->taskMapper->insert($taskEntity);
+		$task->setId($taskEntity->getId());
+		$this->jobList->add(TaskBackgroundJob::class, [
+			'taskId' => $task->getId()
+		]);
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function runOrScheduleTask(Task $task) : void {
+		if (!$this->hasProviders()) {
+			throw new PreConditionNotMetException('No text to image provider is installed that can handle this task');
+		}
+		$providers = $this->getProviders();
+
+		$json = $this->config->getAppValue('core', 'ai.text2image_provider', '');
+		if ($json !== '') {
+			try {
+				$id = json_decode($json, true, 512, JSON_THROW_ON_ERROR);
+				$provider = current(array_filter($providers, fn ($provider) => $provider->getId() === $id));
+				if ($provider !== false) {
+					$providers = [$provider];
+				}
+			} catch (\JsonException $e) {
+				$this->logger->warning('Failed to decode Text2Image setting `ai.text2image_provider`', ['exception' => $e]);
+			}
+		}
+		$maxExecutionTime = (int) ini_get('max_execution_time');
+		// Offload the tttttttask to a background job if the expected runtime of the likely provider is longer than 80% of our max execution time
+		if ($providers[0]->getExpectedRuntime() > $maxExecutionTime * 0.8) {
+			$this->scheduleTask($task);
+			return;
+		}
+		$this->runTask($task);
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function deleteTask(Task $task): void {
+		$taskEntity = DbTask::fromPublicTask($task);
+		$this->taskMapper->delete($taskEntity);
+		$this->jobList->remove(TaskBackgroundJob::class, [
+			'taskId' => $task->getId()
+		]);
+	}
+
+	/**
+	 * Get a task from its id
+	 *
+	 * @param int $id The id of the task
+	 * @return Task
+	 * @throws RuntimeException If the query failed
+	 * @throws TaskNotFoundException If the task could not be found
+	 */
+	public function getTask(int $id): Task {
+		try {
+			$taskEntity = $this->taskMapper->find($id);
+			return $taskEntity->toPublicTask();
+		} catch (DoesNotExistException $e) {
+			throw new TaskNotFoundException('Could not find task with the provided id');
+		} catch (MultipleObjectsReturnedException $e) {
+			throw new RuntimeException('Could not uniquely identify task with given id', 0, $e);
+		} catch (Exception $e) {
+			throw new RuntimeException('Failure while trying to find task by id: ' . $e->getMessage(), 0, $e);
+		}
+	}
+
+	/**
+	 * Get a task from its user id and task id
+	 * If userId is null, this can only get a task that was scheduled anonymously
+	 *
+	 * @param int $id The id of the task
+	 * @param string|null $userId The user id that scheduled the task
+	 * @return Task
+	 * @throws RuntimeException If the query failed
+	 * @throws TaskNotFoundException If the task could not be found
+	 */
+	public function getUserTask(int $id, ?string $userId): Task {
+		try {
+			$taskEntity = $this->taskMapper->findByIdAndUser($id, $userId);
+			return $taskEntity->toPublicTask();
+		} catch (DoesNotExistException $e) {
+			throw new TaskNotFoundException('Could not find task with the provided id and user id');
+		} catch (MultipleObjectsReturnedException $e) {
+			throw new RuntimeException('Could not uniquely identify task with given id and user id', 0, $e);
+		} catch (Exception $e) {
+			throw new RuntimeException('Failure while trying to find task by id and user id: ' . $e->getMessage(), 0, $e);
+		}
+	}
+
+	/**
+	 * Get a list of tasks scheduled by a specific user for a specific app
+	 * and optionally with a specific identifier.
+	 * This cannot be used to get anonymously scheduled tasks
+	 *
+	 * @param string $userId
+	 * @param string $appId
+	 * @param string|null $identifier
+	 * @return Task[]
+	 * @throws RuntimeException
+	 */
+	public function getUserTasksByApp(?string $userId, string $appId, ?string $identifier = null): array {
+		try {
+			$taskEntities = $this->taskMapper->findUserTasksByApp($userId, $appId, $identifier);
+			return array_map(static function (DbTask $taskEntity) {
+				return $taskEntity->toPublicTask();
+			}, $taskEntities);
+		} catch (Exception $e) {
+			throw new RuntimeException('Failure while trying to find tasks by appId and identifier: ' . $e->getMessage(), 0, $e);
+		}
+	}
+}
diff --git a/lib/private/TextToImage/RemoveOldTasksBackgroundJob.php b/lib/private/TextToImage/RemoveOldTasksBackgroundJob.php
new file mode 100644
index 00000000000..2ecebc241bf
--- /dev/null
+++ b/lib/private/TextToImage/RemoveOldTasksBackgroundJob.php
@@ -0,0 +1,78 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2023 Marcel Klehr <mklehr@gmx.net>
+ *
+ * @author Marcel Klehr <mklehr@gmx.net>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+namespace OC\TextToImage;
+
+use OC\TextToImage\Db\TaskMapper;
+use OCP\AppFramework\Utility\ITimeFactory;
+use OCP\BackgroundJob\TimedJob;
+use OCP\DB\Exception;
+use OCP\Files\AppData\IAppDataFactory;
+use OCP\Files\IAppData;
+use OCP\Files\NotFoundException;
+use OCP\Files\NotPermittedException;
+use Psr\Log\LoggerInterface;
+
+class RemoveOldTasksBackgroundJob extends TimedJob {
+	public const MAX_TASK_AGE_SECONDS = 60 * 50 * 24 * 7; // 1 week
+
+	private IAppData $appData;
+
+	public function __construct(
+		ITimeFactory $timeFactory,
+		private TaskMapper $taskMapper,
+		private LoggerInterface $logger,
+		IAppDataFactory $appDataFactory,
+	) {
+		parent::__construct($timeFactory);
+		$this->appData = $appDataFactory->get('core');
+		$this->setInterval(60 * 60 * 24);
+	}
+
+	/**
+	 * @param mixed $argument
+	 * @inheritDoc
+	 */
+	protected function run($argument) {
+		try {
+			$deletedTasks = $this->taskMapper->deleteOlderThan(self::MAX_TASK_AGE_SECONDS);
+			$folder = $this->appData->getFolder('text2image');
+			foreach ($deletedTasks as $deletedTask) {
+				try {
+					$folder->getFolder((string)$deletedTask->getId())->delete();
+				} catch (NotFoundException) {
+					// noop
+				} catch (NotPermittedException $e) {
+					$this->logger->warning('Failed to delete stale text to image task files', ['exception' => $e]);
+				}
+			}
+		} catch (Exception $e) {
+			$this->logger->warning('Failed to delete stale text to image tasks', ['exception' => $e]);
+		} catch(NotFoundException) {
+			// noop
+		}
+	}
+}
diff --git a/lib/private/TextToImage/TaskBackgroundJob.php b/lib/private/TextToImage/TaskBackgroundJob.php
new file mode 100644
index 00000000000..ac5cd6b59b5
--- /dev/null
+++ b/lib/private/TextToImage/TaskBackgroundJob.php
@@ -0,0 +1,63 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * @copyright Copyright (c) 2023 Marcel Klehr <mklehr@gmx.net>
+ *
+ * @author Marcel Klehr <mklehr@gmx.net>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+
+namespace OC\TextToImage;
+
+use OCP\AppFramework\Utility\ITimeFactory;
+use OCP\BackgroundJob\QueuedJob;
+use OCP\EventDispatcher\IEventDispatcher;
+use OCP\TextToImage\Events\TaskFailedEvent;
+use OCP\TextToImage\Events\TaskSuccessfulEvent;
+use OCP\TextToImage\IManager;
+
+class TaskBackgroundJob extends QueuedJob {
+	public function __construct(
+		ITimeFactory $timeFactory,
+		private IManager $text2imageManager,
+		private IEventDispatcher $eventDispatcher,
+	) {
+		parent::__construct($timeFactory);
+		// We want to avoid overloading the machine with these jobs
+		// so we only allow running one job at a time
+		$this->setAllowParallelRuns(false);
+	}
+
+	/**
+	 * @param array{taskId: int} $argument
+	 * @inheritDoc
+	 */
+	protected function run($argument) {
+		$taskId = $argument['taskId'];
+		$task = $this->text2imageManager->getTask($taskId);
+		try {
+			$this->text2imageManager->runTask($task);
+			$event = new TaskSuccessfulEvent($task);
+		} catch (\Throwable $e) {
+			$event = new TaskFailedEvent($task, $e->getMessage());
+		}
+		$this->eventDispatcher->dispatchTyped($event);
+	}
+}