do not store state in appconfig

- and use count over isset for better understanding

Signed-off-by: Arthur Schiwon <blizzz@arthur-schiwon.de>

apps/theming/lib/Jobs/MigrateBackgroundImages.php

@@ -31,35 +31,41 @@ use OCP\AppFramework\Utility\ITimeFactory;
 use OCP\BackgroundJob\IJobList;
 use OCP\BackgroundJob\QueuedJob;
 use OCP\Files\AppData\IAppDataFactory;
+use OCP\Files\IAppData;
 use OCP\Files\NotFoundException;
 use OCP\Files\NotPermittedException;
 use OCP\Files\SimpleFS\ISimpleFolder;
-use OCP\IConfig;
 use OCP\IDBConnection;
+use Psr\Log\LoggerInterface;
 
 class MigrateBackgroundImages extends QueuedJob {
 	public const TIME_SENSITIVE = 0;
 
 	protected const STAGE_PREPARE = 'prepare';
 	protected const STAGE_EXECUTE = 'execute';
+	// will be saved in appdata/theming/global/
+	protected const STATE_FILE_NAME = '25_dashboard_to_theming_migration_users.txt';
 
-	private IConfig $config;
 	private IAppDataFactory $appDataFactory;
 	private IJobList $jobList;
 	private IDBConnection $dbc;
+	private IAppData $appData;
+	private LoggerInterface $logger;
 
 	public function __construct(
 		ITimeFactory $time,
 		IAppDataFactory $appDataFactory,
-		IConfig $config,
 		IJobList $jobList,
-		IDBConnection $dbc
+		IDBConnection $dbc,
+		IAppData $appData,
+		LoggerInterface $logger
 	) {
 		parent::__construct($time);
-		$this->config = $config;
 		$this->appDataFactory = $appDataFactory;
 		$this->jobList = $jobList;
 		$this->dbc = $dbc;
+		$this->appData = $appData;
+		$this->logger = $logger;
 	}
 
 	protected function run($argument): void {
@@ -99,13 +105,13 @@ class MigrateBackgroundImages extends QueuedJob {
 		$this->jobList->add(self::class, self::STAGE_EXECUTE);
 	}
 
+	/**
+	 * @throws NotPermittedException
+	 * @throws NotFoundException
+	 */
 	protected function runMigration(): void {
-		$storedUserIds = $this->config->getAppValue('theming', '25_background_image_migration');
-		if ($storedUserIds === '') {
-			return;
-		}
-		$allUserIds = \json_decode(\gzuncompress($storedUserIds), true);
-		$notSoFastMode = isset($allUserIds[5000]);
+		$allUserIds = $this->readUserIdsToProcess();
+		$notSoFastMode = count($allUserIds) > 5000;
 		$dashboardData = $this->appDataFactory->get('dashboard');
 
 		$userIds = $notSoFastMode ? array_slice($allUserIds, 0, 5000) : $allUserIds;
@@ -128,13 +134,76 @@ class MigrateBackgroundImages extends QueuedJob {
 			$this->storeUserIdsToProcess($remainingUserIds);
 			$this->jobList->add(self::class, ['stage' => self::STAGE_EXECUTE]);
 		} else {
-			$this->config->deleteAppValue('theming', '25_background_image_migration');
+			$this->deleteStateFile();
 		}
 	}
 
+	/**
+	 * @throws NotPermittedException
+	 * @throws NotFoundException
+	 */
+	protected function readUserIdsToProcess(): array {
+		$globalFolder = $this->appData->getFolder('global');
+		if ($globalFolder->fileExists(self::STATE_FILE_NAME)) {
+			$file = $globalFolder->getFile(self::STATE_FILE_NAME);
+			try {
+				$userIds = \json_decode($file->getContent(), true);
+			} catch (NotFoundException $e) {
+				$userIds = [];
+			}
+			if ($userIds === null) {
+				$userIds = [];
+			}
+		} else {
+			$userIds = [];
+		}
+		return $userIds;
+	}
+
+	/**
+	 * @throws NotFoundException
+	 */
 	protected function storeUserIdsToProcess(array $userIds): void {
-		$storableUserIds = \gzcompress(\json_encode($userIds), 9);
-		$this->config->setAppValue('theming', '25_background_image_migration', $storableUserIds);
+		$storableUserIds = \json_encode($userIds);
+		$globalFolder = $this->appData->getFolder('global');
+		try {
+			if ($globalFolder->fileExists(self::STATE_FILE_NAME)) {
+				$file = $globalFolder->getFile(self::STATE_FILE_NAME);
+			} else {
+				$file = $globalFolder->newFile(self::STATE_FILE_NAME);
+			}
+			$file->putContent($storableUserIds);
+		} catch (NotFoundException $e) {
+		} catch (NotPermittedException $e) {
+			$this->logger->warning('Lacking permissions to create {file}',
+				[
+					'app' => 'theming',
+					'file' => self::STATE_FILE_NAME,
+					'exception' => $e,
+				]
+			);
+		}
+	}
+
+	/**
+	 * @throws NotFoundException
+	 */
+	protected function deleteStateFile(): void {
+		$globalFolder = $this->appData->getFolder('global');
+		if ($globalFolder->fileExists(self::STATE_FILE_NAME)) {
+			$file = $globalFolder->getFile(self::STATE_FILE_NAME);
+			try {
+				$file->delete();
+			} catch (NotPermittedException $e) {
+				$this->logger->info('Could not delete {name} due to permissions. It is safe to delete manually inside data -> appdata -> theming -> global.',
+					[
+						'app' => 'theming',
+						'name' => $file->getName(),
+						'exception' => $e,
+					]
+				);
+			}
+		}
 	}
 
 	/**