fix(files): Continue scanning after StorageInvalidException

When a federated share was already removed on the remote end, accessing it triggers a `StorageInvalidException` after the share and its mount are removed locally. When running `occ files:scan`, this exception isn't caught by the scanner and aborts the scan of all remaining mounts of that user, printing a stack trace instead. This can be pretty frustrating on larger instances with many federated shares.

To avoid that, the `StorageInvalidException` is now caught and handled the same way as the `StorageNotAvailableException`: log it as an error, report it through the `StorageNotAvailable` hook and continue with the next mount.

Assisted-by: ClaudeCode:claude-opus-5-5
Signed-off-by: David Dreschner <david.dreschner@nextcloud.com>

[skip ci]

Author: DerDreschner

apps/files/lib/Command/Scan.php

@@ -22,6 +22,7 @@
 use OCP\Files\IRootFolder;
 use OCP\Files\Mount\IMountPoint;
 use OCP\Files\NotFoundException;
+use OCP\Files\StorageInvalidException;
 use OCP\Files\StorageNotAvailableException;
 use OCP\FilesMetadata\IFilesMetadataManager;
 use OCP\IUserManager;

apps/files/lib/Command/ScanAppData.php

@@ -18,6 +18,7 @@
 use OCP\Files\IRootFolder;
 use OCP\Files\Node;
 use OCP\Files\NotFoundException;
+use OCP\Files\StorageInvalidException;
 use OCP\Files\StorageNotAvailableException;
 use OCP\IConfig;
 use OCP\Server;

apps/files/tests/Command/ScanAppDataTest.php

@@ -24,6 +24,7 @@
 use OCP\Files\IRootFolder;
 use OCP\Files\NotFoundException;
 use OCP\Files\Storage\IStorageFactory;
+use OCP\Files\StorageInvalidException;
 use OCP\IAppConfig;
 use OCP\IConfig;
 use OCP\IUser;

lib/private/Files/Utils/Scanner.php

@@ -26,6 +26,7 @@
 use OCP\Files\Mount\IMountPoint;
 use OCP\Files\NotFoundException;
 use OCP\Files\Storage\IStorage;
+use OCP\Files\StorageInvalidException;
 use OCP\Files\StorageNotAvailableException;
 use OCP\IDBConnection;
 use OCP\Lock\ILockingProvider;
@@ -257,7 +258,7 @@ public function scan($dir = '', $recursive = \OC\Files\Cache\Scanner::SCAN_RECUR
 					$cache->correctFolderSize($relativePath);
 				}
 				$propagator->commitBatch();
-			} catch (StorageNotAvailableException $e) {
+			} catch (StorageNotAvailableException|StorageInvalidException $e) {
 				$this->logger->error('Storage ' . $storage->getId() . ' not available', ['exception' => $e]);
 				$this->emit('\OC\Files\Utils\Scanner', 'StorageNotAvailable', [$e]);
 			}

tests/lib/Files/Utils/ScannerTest.php

@@ -16,6 +16,8 @@
 use OCP\Files\Config\IMountProvider;
 use OCP\Files\Config\IMountProviderCollection;
 use OCP\Files\Storage\IStorageFactory;
+use OCP\Files\StorageInvalidException;
+use OCP\Files\StorageNotAvailableException;
 use OCP\IDBConnection;
 use OCP\IUser;
 use OCP\IUserManager;
@@ -223,4 +225,45 @@ public function testShallow(): void {
 		$this->assertTrue($cache->inCache('folder/bar.txt'));
 		$this->assertFalse($cache->inCache('folder/subfolder/foobar.txt'));
 	}
+
+	public function testScanContinuesAfterInvalidStorage(): void {
+		$invalidStorage = new class([]) extends Temporary {
+			#[\Override]
+			public function getMetaData(string $path): ?array {
+				throw new StorageInvalidException('Remote share not found');
+			}
+		};
+		$storage = new Temporary([]);
+		$storage->file_put_contents('foo.txt', 'qwerty');
+
+		$logger = $this->createMock(LoggerInterface::class);
+		$logger->expects($this->once())
+			->method('error')
+			->with(
+				'Storage ' . $invalidStorage->getId() . ' not available',
+				$this->callback(fn (array $context): bool => $context['exception'] instanceof StorageInvalidException),
+			);
+
+		$scanner = new TestScanner(
+			Server::get(IUserManager::class)->get(''),
+			Server::get(IDBConnection::class),
+			$this->createMock(IEventDispatcher::class),
+			$logger,
+			Server::get(SetupManager::class),
+		);
+		$scanner->addMount(new MountPoint($invalidStorage, '/invalid'));
+		$scanner->addMount(new MountPoint($storage, '/valid'));
+
+		$emitted = [];
+		$scanner->listen('\OC\Files\Utils\Scanner', 'StorageNotAvailable', function (StorageNotAvailableException|StorageInvalidException $e) use (&$emitted): void {
+			$emitted[] = $e;
+		});
+
+		$scanner->scan('');
+
+		$this->assertCount(1, $emitted);
+		$this->assertInstanceOf(StorageInvalidException::class, $emitted[0]);
+		$this->assertSame('Remote share not found', $emitted[0]->getMessage());
+		$this->assertTrue($storage->getCache()->inCache('foo.txt'));
+	}
 }