Adapt multipart upload to use sse-kms parameters

Signed-off-by: Julius Härtl <jus@bitgrid.net>

apps/dav/composer/composer/autoload_classmap.php

@@ -248,6 +248,7 @@ return array(
     'OCA\\DAV\\Search\\EventsSearchProvider' => $baseDir . '/../lib/Search/EventsSearchProvider.php',
     'OCA\\DAV\\Search\\TasksSearchProvider' => $baseDir . '/../lib/Search/TasksSearchProvider.php',
     'OCA\\DAV\\Server' => $baseDir . '/../lib/Server.php',
+    'OCA\\DAV\\Service\\CustomPropertiesService' => $baseDir . '/../lib/Service/CustomPropertiesService.php',
     'OCA\\DAV\\Settings\\CalDAVSettings' => $baseDir . '/../lib/Settings/CalDAVSettings.php',
     'OCA\\DAV\\Storage\\PublicOwnerWrapper' => $baseDir . '/../lib/Storage/PublicOwnerWrapper.php',
     'OCA\\DAV\\SystemTag\\SystemTagMappingNode' => $baseDir . '/../lib/SystemTag/SystemTagMappingNode.php',
@@ -260,6 +261,7 @@ return array(
     'OCA\\DAV\\Traits\\PrincipalProxyTrait' => $baseDir . '/../lib/Traits/PrincipalProxyTrait.php',
     'OCA\\DAV\\Upload\\AssemblyStream' => $baseDir . '/../lib/Upload/AssemblyStream.php',
     'OCA\\DAV\\Upload\\ChunkingPlugin' => $baseDir . '/../lib/Upload/ChunkingPlugin.php',
+    'OCA\\DAV\\Upload\\ChunkingV2Plugin' => $baseDir . '/../lib/Upload/ChunkingV2Plugin.php',
     'OCA\\DAV\\Upload\\CleanupService' => $baseDir . '/../lib/Upload/CleanupService.php',
     'OCA\\DAV\\Upload\\FutureFile' => $baseDir . '/../lib/Upload/FutureFile.php',
     'OCA\\DAV\\Upload\\RootCollection' => $baseDir . '/../lib/Upload/RootCollection.php',

apps/dav/composer/composer/autoload_static.php

@@ -263,6 +263,7 @@ class ComposerStaticInitDAV
         'OCA\\DAV\\Search\\EventsSearchProvider' => __DIR__ . '/..' . '/../lib/Search/EventsSearchProvider.php',
         'OCA\\DAV\\Search\\TasksSearchProvider' => __DIR__ . '/..' . '/../lib/Search/TasksSearchProvider.php',
         'OCA\\DAV\\Server' => __DIR__ . '/..' . '/../lib/Server.php',
+        'OCA\\DAV\\Service\\CustomPropertiesService' => __DIR__ . '/..' . '/../lib/Service/CustomPropertiesService.php',
         'OCA\\DAV\\Settings\\CalDAVSettings' => __DIR__ . '/..' . '/../lib/Settings/CalDAVSettings.php',
         'OCA\\DAV\\Storage\\PublicOwnerWrapper' => __DIR__ . '/..' . '/../lib/Storage/PublicOwnerWrapper.php',
         'OCA\\DAV\\SystemTag\\SystemTagMappingNode' => __DIR__ . '/..' . '/../lib/SystemTag/SystemTagMappingNode.php',
@@ -275,6 +276,7 @@ class ComposerStaticInitDAV
         'OCA\\DAV\\Traits\\PrincipalProxyTrait' => __DIR__ . '/..' . '/../lib/Traits/PrincipalProxyTrait.php',
         'OCA\\DAV\\Upload\\AssemblyStream' => __DIR__ . '/..' . '/../lib/Upload/AssemblyStream.php',
         'OCA\\DAV\\Upload\\ChunkingPlugin' => __DIR__ . '/..' . '/../lib/Upload/ChunkingPlugin.php',
+        'OCA\\DAV\\Upload\\ChunkingV2Plugin' => __DIR__ . '/..' . '/../lib/Upload/ChunkingV2Plugin.php',
         'OCA\\DAV\\Upload\\CleanupService' => __DIR__ . '/..' . '/../lib/Upload/CleanupService.php',
         'OCA\\DAV\\Upload\\FutureFile' => __DIR__ . '/..' . '/../lib/Upload/FutureFile.php',
         'OCA\\DAV\\Upload\\RootCollection' => __DIR__ . '/..' . '/../lib/Upload/RootCollection.php',

apps/dav/lib/BackgroundJob/UploadCleanup.php

@@ -29,6 +29,7 @@ declare(strict_types=1);
 namespace OCA\DAV\BackgroundJob;
 
 use OC\User\NoUserException;
+use OCA\DAV\Service\CustomPropertiesService;
 use OCP\AppFramework\Utility\ITimeFactory;
 use OCP\BackgroundJob\IJobList;
 use OCP\BackgroundJob\TimedJob;
@@ -45,10 +46,14 @@ class UploadCleanup extends TimedJob {
 	/** @var IJobList */
 	private $jobList;
 
-	public function __construct(ITimeFactory $time, IRootFolder $rootFolder, IJobList $jobList) {
+	/** @var CustomPropertiesService */
+	private $customPropertiesService;
+
+	public function __construct(ITimeFactory $time, IRootFolder $rootFolder, IJobList $jobList, CustomPropertiesService $customPropertiesService) {
 		parent::__construct($time);
 		$this->rootFolder = $rootFolder;
 		$this->jobList = $jobList;
+		$this->customPropertiesService = $customPropertiesService;
 
 		// Run once a day
 		$this->setInterval(60 * 60 * 24);
@@ -72,6 +77,9 @@ class UploadCleanup extends TimedJob {
 
 		$files = $uploadFolder->getDirectoryListing();
 
+		$davPath = 'uploads/' . $uid . '/' . $uploadFolder->getName();
+		$this->customPropertiesService->delete($uid, $davPath);
+
 		// Remove if all files have an mtime of more than a day
 		$time = $this->time->getTime() - 60 * 60 * 24;
 

apps/dav/lib/Connector/Sabre/Directory.php

@@ -38,6 +38,7 @@ use OC\Files\View;
 use OCA\DAV\Connector\Sabre\Exception\FileLocked;
 use OCA\DAV\Connector\Sabre\Exception\Forbidden;
 use OCA\DAV\Connector\Sabre\Exception\InvalidPath;
+use OCA\DAV\Upload\FutureFile;
 use OCP\Files\FileInfo;
 use OCP\Files\ForbiddenException;
 use OCP\Files\InvalidPathException;

apps/dav/lib/Connector/Sabre/Node.php

@@ -248,6 +248,14 @@ abstract class Node implements \Sabre\DAV\INode {
 		return $this->info->getId();
 	}
 
+	public function getInternalPath(): string {
+		return $this->info->getInternalPath();
+	}
+
+	public function getAbsoluteInternalPath(): string {
+		return $this->info->getPath();
+	}
+
 	/**
 	 * @param string $user
 	 * @return int

apps/dav/lib/Connector/Sabre/ServerFactory.php

@@ -35,6 +35,7 @@ namespace OCA\DAV\Connector\Sabre;
 use OC\Files\Node\Folder;
 use OCA\DAV\AppInfo\PluginManager;
 use OCA\DAV\Files\BrowserErrorPagePlugin;
+use OCA\DAV\Service\CustomPropertiesService;
 use OCP\Files\Mount\IMountManager;
 use OCP\IConfig;
 use OCP\IDBConnection;
@@ -204,6 +205,7 @@ class ServerFactory {
 						new \OCA\DAV\DAV\CustomPropertiesBackend(
 							$objectTree,
 							$this->databaseConnection,
+							\OC::$server->get(CustomPropertiesService::class),
 							$this->userSession->getUser()
 						)
 					)

apps/dav/lib/DAV/CustomPropertiesBackend.php

@@ -26,6 +26,7 @@
 namespace OCA\DAV\DAV;
 
 use OCA\DAV\Connector\Sabre\Node;
+use OCA\DAV\Service\CustomPropertiesService;
 use OCP\IDBConnection;
 use OCP\IUser;
 use Sabre\DAV\PropertyStorage\Backend\BackendInterface;
@@ -63,6 +64,11 @@ class CustomPropertiesBackend implements BackendInterface {
 	 */
 	private $connection;
 
+	/**
+	 * @var CustomPropertiesService
+	 */
+	private $customPropertiesService;
+
 	/**
 	 * @var IUser
 	 */
@@ -83,9 +89,11 @@ class CustomPropertiesBackend implements BackendInterface {
 	public function __construct(
 		Tree $tree,
 		IDBConnection $connection,
+		CustomPropertiesService $customPropertiesService,
 		IUser $user) {
 		$this->tree = $tree;
 		$this->connection = $connection;
+		$this->customPropertiesService = $customPropertiesService;
 		$this->user = $user;
 	}
 
@@ -155,12 +163,7 @@ class CustomPropertiesBackend implements BackendInterface {
 	 * @param string $path path of node for which to delete properties
 	 */
 	public function delete($path) {
-		$statement = $this->connection->prepare(
-			'DELETE FROM `*PREFIX*properties` WHERE `userid` = ? AND `propertypath` = ?'
-		);
-		$statement->execute([$this->user->getUID(), $this->formatPath($path)]);
-		$statement->closeCursor();
-
+		$this->customPropertiesService->delete($this->user->getUID(), $path);
 		unset($this->cache[$path]);
 	}
 

apps/dav/lib/Server.php

@@ -64,8 +64,10 @@ use OCA\DAV\Events\SabrePluginAuthInitEvent;
 use OCA\DAV\Files\BrowserErrorPagePlugin;
 use OCA\DAV\Files\LazySearchBackend;
 use OCA\DAV\Provisioning\Apple\AppleProvisioningPlugin;
+use OCA\DAV\Service\CustomPropertiesService;
 use OCA\DAV\SystemTag\SystemTagPlugin;
 use OCA\DAV\Upload\ChunkingPlugin;
+use OCA\DAV\Upload\ChunkingV2Plugin;
 use OCP\EventDispatcher\IEventDispatcher;
 use OCP\IRequest;
 use OCP\SabrePluginEvent;
@@ -203,6 +205,7 @@ class Server {
 		));
 
 		$this->server->addPlugin(new CopyEtagHeaderPlugin());
+		$this->server->addPlugin(new ChunkingV2Plugin());
 		$this->server->addPlugin(new ChunkingPlugin());
 
 		// allow setup of additional plugins
@@ -248,6 +251,7 @@ class Server {
 						new CustomPropertiesBackend(
 							$this->server->tree,
 							\OC::$server->getDatabaseConnection(),
+							\OC::$server->get(CustomPropertiesService::class),
 							\OC::$server->getUserSession()->getUser()
 						)
 					)

apps/dav/lib/Service/CustomPropertiesService.php

@@ -0,0 +1,60 @@
+<?php
+/*
+ * @copyright Copyright (c) 2021 Julius Härtl <jus@bitgrid.net>
+ *
+ * @author Julius Härtl <jus@bitgrid.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/>.
+ *
+ */
+
+declare(strict_types=1);
+
+
+namespace OCA\DAV\Service;
+
+use OCP\IDBConnection;
+
+class CustomPropertiesService {
+
+	/** @var IDBConnection */
+	private $connection;
+
+	public function __construct(IDBConnection $connection) {
+		$this->connection = $connection;
+	}
+
+	public function delete(string $userId, string $path): void {
+		$statement = $this->connection->prepare(
+			'DELETE FROM `*PREFIX*properties` WHERE `userid` = ? AND `propertypath` = ?'
+		);
+		$result = $statement->execute([$userId, $this->formatPath($path)]);
+		$result->closeCursor();
+	}
+
+	/**
+	 * long paths are hashed to ensure they fit in the database
+	 *
+	 * @param string $path
+	 * @return string
+	 */
+	private function formatPath(string $path): string {
+		if (strlen($path) > 250) {
+			return sha1($path);
+		}
+		return $path;
+	}
+}

apps/dav/lib/Upload/ChunkingV2Plugin.php

@@ -0,0 +1,223 @@
+<?php
+
+declare(strict_types=1);
+/*
+ * @copyright Copyright (c) 2021 Julius Härtl <jus@bitgrid.net>
+ *
+ * @author Julius Härtl <jus@bitgrid.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 OCA\DAV\Upload;
+
+use OC\Files\View;
+use OCA\DAV\Connector\Sabre\Directory;
+use OCP\Files\Storage\IChunkedFileWrite;
+use OCP\Files\Storage\IStorage;
+use OCP\Files\StorageInvalidException;
+use Sabre\DAV\Exception\BadRequest;
+use Sabre\DAV\Exception\NotFound;
+use Sabre\DAV\Server;
+use Sabre\DAV\ServerPlugin;
+use Sabre\HTTP\RequestInterface;
+use Sabre\HTTP\ResponseInterface;
+use Sabre\Uri;
+
+class ChunkingV2Plugin extends ServerPlugin {
+
+	/** @var Server */
+	private $server;
+	/** @var UploadFolder */
+	private $uploadFolder;
+
+	private const TEMP_TARGET = '.target';
+
+	private const OBJECT_UPLOAD_TARGET = '{http://nextcloud.org/ns}upload-target';
+	private const OBJECT_UPLOAD_CHUNKTOKEN = '{http://nextcloud.org/ns}upload-chunktoken';
+
+	private const DESTINATION_HEADER = 'X-Chunking-Destination';
+
+	/**
+	 * @inheritdoc
+	 */
+	public function initialize(Server $server) {
+		$server->on('afterMethod:MKCOL', [$this, 'beforeMkcol']);
+		// 200 priority to call after the custom properties backend is registered
+		$server->on('beforeMethod:PUT', [$this, 'beforePut'], 200);
+		$server->on('beforeMethod:DELETE', [$this, 'beforeDelete'], 200);
+		$server->on('beforeMove', [$this, 'beforeMove'], 90);
+
+		$this->server = $server;
+	}
+
+	/**
+	 * @param string $path
+	 * @param bool $createIfNotExists
+	 * @return FutureFile|UploadFile|\Sabre\DAV\ICollection|\Sabre\DAV\INode
+	 */
+	private function getTargetFile(string $path, bool $createIfNotExists = false) {
+		try {
+			$targetFile = $this->server->tree->getNodeForPath($path);
+		} catch (NotFound $e) {
+			if ($createIfNotExists) {
+				$this->uploadFolder->createFile(self::TEMP_TARGET);
+			}
+			$targetFile = $this->uploadFolder->getChild(self::TEMP_TARGET);
+		}
+		return $targetFile;
+	}
+
+	public function beforeMkcol(RequestInterface $request, ResponseInterface $response): bool {
+		$this->uploadFolder = $this->server->tree->getNodeForPath($request->getPath());
+		try {
+			$this->checkPrerequisites();
+			$storage = $this->getStorage();
+		} catch (StorageInvalidException | BadRequest $e) {
+			return true;
+		}
+
+		$targetPath = $this->server->httpRequest->getHeader(self::DESTINATION_HEADER);
+		if (!$targetPath) {
+			return true;
+		}
+
+		$targetFile = $this->getTargetFile($targetPath, true);
+
+		$uploadId = $storage->beginChunkedFile($targetFile->getInternalPath());
+
+		// DAV properties on the UploadFolder are used in order to properly cleanup stale chunked file writes and to persist the target path
+		$this->server->updateProperties($request->getPath(), [
+			self::OBJECT_UPLOAD_CHUNKTOKEN => $uploadId,
+			self::OBJECT_UPLOAD_TARGET => $targetPath,
+		]);
+
+		$response->setStatus(201);
+		return true;
+	}
+
+	public function beforePut(RequestInterface $request, ResponseInterface $response): bool {
+		$this->uploadFolder = $this->server->tree->getNodeForPath(dirname($request->getPath()));
+		try {
+			$this->checkPrerequisites();
+			$storage = $this->getStorage();
+		} catch (StorageInvalidException | BadRequest $e) {
+			return true;
+		}
+
+		$properties = $this->server->getProperties(dirname($request->getPath()) . '/', [ self::OBJECT_UPLOAD_CHUNKTOKEN, self::OBJECT_UPLOAD_TARGET ]);
+		$targetPath = $properties[self::OBJECT_UPLOAD_TARGET];
+		$uploadId = $properties[self::OBJECT_UPLOAD_CHUNKTOKEN];
+		$partId = (int)basename($request->getPath());
+
+		if (!($partId >= 1 && $partId <= 10000)) {
+			throw new BadRequest('Invalid chunk id');
+		}
+
+		$targetFile = $this->getTargetFile($targetPath);
+		$stream = $request->getBodyAsStream();
+		$storage->putChunkedFilePart($targetFile->getInternalPath(), $uploadId, (string)$partId, $stream, (int)$request->getHeader('Content-Length'));
+
+		$response->setStatus(201);
+		return false;
+	}
+
+	public function beforeMove($sourcePath, $destination): bool {
+		$this->uploadFolder = $this->server->tree->getNodeForPath(dirname($sourcePath));
+		try {
+			$this->checkPrerequisites();
+			$this->getStorage();
+		} catch (StorageInvalidException | BadRequest $e) {
+			return true;
+		}
+		$properties = $this->server->getProperties(dirname($sourcePath) . '/', [ self::OBJECT_UPLOAD_CHUNKTOKEN, self::OBJECT_UPLOAD_TARGET ]);
+		$targetPath = $properties[self::OBJECT_UPLOAD_TARGET];
+		$uploadId = $properties[self::OBJECT_UPLOAD_CHUNKTOKEN];
+
+		$targetFile = $this->getTargetFile($targetPath);
+
+		[$destinationDir, $destinationName] = Uri\split($destination);
+		/** @var Directory $destinationParent */
+		$destinationParent = $this->server->tree->getNodeForPath($destinationDir);
+		$destinationExists = $destinationParent->childExists($destinationName);
+
+		$rootView = new View();
+		$rootView->writeChunkedFile($targetFile->getAbsoluteInternalPath(), $uploadId);
+		if (!$destinationExists) {
+			$destinationInView = $destinationParent->getFileInfo()->getPath() . '/' . $destinationName;
+			$rootView->rename($targetFile->getAbsoluteInternalPath(), $destinationInView);
+		}
+
+		$sourceNode = $this->server->tree->getNodeForPath($sourcePath);
+		if ($sourceNode instanceof FutureFile) {
+			$sourceNode->delete();
+		}
+
+		$this->server->emit('afterMove', [$sourcePath, $destination]);
+		$this->server->emit('afterUnbind', [$sourcePath]);
+		$this->server->emit('afterBind', [$destination]);
+
+		$response = $this->server->httpResponse;
+		$response->setHeader('Content-Length', '0');
+		$response->setStatus($destinationExists ? 204 : 201);
+		return false;
+	}
+
+	public function beforeDelete(RequestInterface $request, ResponseInterface $response) {
+		$this->uploadFolder = $this->server->tree->getNodeForPath($request->getPath());
+		try {
+			if (!$this->uploadFolder instanceof UploadFolder) {
+				return true;
+			}
+			$storage = $this->getStorage();
+		} catch (StorageInvalidException | BadRequest $e) {
+			return true;
+		}
+
+		$properties = $this->server->getProperties($request->getPath() . '/', [ self::OBJECT_UPLOAD_CHUNKTOKEN, self::OBJECT_UPLOAD_TARGET ]);
+		$targetPath = $properties[self::OBJECT_UPLOAD_TARGET];
+		$uploadId = $properties[self::OBJECT_UPLOAD_CHUNKTOKEN];
+		if (!$targetPath || !$uploadId) {
+			return true;
+		}
+		$targetFile = $this->getTargetFile($targetPath);
+		$storage->cancelChunkedFile($targetFile->getInternalPath(), $uploadId);
+		return true;
+	}
+
+	/** @throws BadRequest */
+	private function checkPrerequisites(): void {
+		if (!$this->uploadFolder instanceof UploadFolder || !$this->server->httpRequest->getHeader(self::DESTINATION_HEADER)) {
+			throw new BadRequest('Chunking destination header not set');
+		}
+	}
+
+	/**
+	 * @return IChunkedFileWrite
+	 * @throws BadRequest
+	 * @throws StorageInvalidException
+	 */
+	private function getStorage(): IStorage {
+		$this->checkPrerequisites();
+		$storage = $this->uploadFolder->getStorage();
+		if (!$storage->instanceOfStorage(IChunkedFileWrite::class)) {
+			throw new StorageInvalidException('Storage does not support chunked file write');
+		}
+		/** @var IChunkedFileWrite $storage */
+		return $storage;
+	}
+}

apps/dav/lib/Upload/FutureFile.php

@@ -68,6 +68,10 @@ class FutureFile implements \Sabre\DAV\IFile {
 		return AssemblyStream::wrap($nodes);
 	}
 
+	public function getPath() {
+		return $this->root->getFileInfo()->getInternalPath() . '/.file';
+	}
+
 	/**
 	 * @inheritdoc
 	 */

apps/dav/lib/Upload/UploadFile.php

@@ -73,4 +73,12 @@ class UploadFile implements IFile {
 	public function getLastModified() {
 		return $this->file->getLastModified();
 	}
+
+	public function getInternalPath(): string {
+		return $this->file->getInternalPath();
+	}
+
+	public function getAbsoluteInternalPath(): string {
+		return $this->file->getFileInfo()->getPath();
+	}
 }

apps/dav/lib/Upload/UploadFolder.php

@@ -26,6 +26,7 @@
 namespace OCA\DAV\Upload;
 
 use OCA\DAV\Connector\Sabre\Directory;
+use OCP\Files\Storage\IStorage;
 use Sabre\DAV\Exception\Forbidden;
 use Sabre\DAV\ICollection;
 
@@ -35,10 +36,13 @@ class UploadFolder implements ICollection {
 	private $node;
 	/** @var CleanupService */
 	private $cleanupService;
+	/** @var IStorage */
+	private $storage;
 
-	public function __construct(Directory $node, CleanupService $cleanupService) {
+	public function __construct(Directory $node, CleanupService $cleanupService, IStorage $storage) {
 		$this->node = $node;
 		$this->cleanupService = $cleanupService;
+		$this->storage = $storage;
 	}
 
 	public function createFile($name, $data = null) {
@@ -95,4 +99,8 @@ class UploadFolder implements ICollection {
 	public function getLastModified() {
 		return $this->node->getLastModified();
 	}
+
+	public function getStorage() {
+		return $this->storage;
+	}
 }

apps/dav/lib/Upload/UploadHome.php

@@ -56,12 +56,12 @@ class UploadHome implements ICollection {
 	}
 
 	public function getChild($name): UploadFolder {
-		return new UploadFolder($this->impl()->getChild($name), $this->cleanupService);
+		return new UploadFolder($this->impl()->getChild($name), $this->cleanupService, $this->getStorage());
 	}
 
 	public function getChildren(): array {
 		return array_map(function ($node) {
-			return new UploadFolder($node, $this->cleanupService);
+			return new UploadFolder($node, $this->cleanupService, $this->getStorage());
 		}, $this->impl()->getChildren());
 	}
 
@@ -90,14 +90,24 @@ class UploadHome implements ICollection {
 	 * @return Directory
 	 */
 	private function impl() {
+		$view = $this->getView();
+		$rootInfo = $view->getFileInfo('');
+		return new Directory($view, $rootInfo);
+	}
+
+	private function getView() {
 		$rootView = new View();
 		$user = \OC::$server->getUserSession()->getUser();
 		Filesystem::initMountPoints($user->getUID());
 		if (!$rootView->file_exists('/' . $user->getUID() . '/uploads')) {
 			$rootView->mkdir('/' . $user->getUID() . '/uploads');
 		}
-		$view = new View('/' . $user->getUID() . '/uploads');
-		$rootInfo = $view->getFileInfo('');
-		return new Directory($view, $rootInfo);
+		return new View('/' . $user->getUID() . '/uploads');
+	}
+
+	private function getStorage() {
+		$view = $this->getView();
+		$storage = $view->getFileInfo('')->getStorage();
+		return $storage;
 	}
 }

apps/dav/tests/unit/Connector/Sabre/CustomPropertiesBackendTest.php

@@ -37,6 +37,7 @@ namespace OCA\DAV\Tests\unit\Connector\Sabre;
 
 use OCA\DAV\Connector\Sabre\Directory;
 use OCA\DAV\Connector\Sabre\File;
+use OCA\DAV\Service\CustomPropertiesService;
 use OCP\IUser;
 use Sabre\DAV\Tree;
 
@@ -88,6 +89,7 @@ class CustomPropertiesBackendTest extends \Test\TestCase {
 		$this->plugin = new \OCA\DAV\DAV\CustomPropertiesBackend(
 			$this->tree,
 			\OC::$server->getDatabaseConnection(),
+			$this->createMock(CustomPropertiesService::class),
 			$this->user
 		);
 	}

apps/dav/tests/unit/DAV/CustomPropertiesBackendTest.php

@@ -29,8 +29,10 @@
 namespace OCA\DAV\Tests\DAV;
 
 use OCA\DAV\DAV\CustomPropertiesBackend;
+use OCA\DAV\Service\CustomPropertiesService;
 use OCP\IDBConnection;
 use OCP\IUser;
+use PHPUnit\Framework\MockObject\MockObject;
 use Sabre\DAV\PropFind;
 use Sabre\DAV\PropPatch;
 use Sabre\DAV\Tree;
@@ -41,16 +43,19 @@ use Test\TestCase;
  */
 class CustomPropertiesBackendTest extends TestCase {
 
-	/** @var Tree | \PHPUnit\Framework\MockObject\MockObject */
+	/** @var Tree | MockObject */
 	private $tree;
 
 	/** @var  IDBConnection */
 	private $dbConnection;
 
-	/** @var IUser | \PHPUnit\Framework\MockObject\MockObject */
+	/** @var CustomPropertiesService */
+	private $customPropertiesService;
+
+	/** @var IUser | MockObject */
 	private $user;
 
-	/** @var CustomPropertiesBackend | \PHPUnit\Framework\MockObject\MockObject */
+	/** @var CustomPropertiesBackend */
 	private $backend;
 
 	protected function setUp(): void {
@@ -62,10 +67,12 @@ class CustomPropertiesBackendTest extends TestCase {
 			->with()
 			->willReturn('dummy_user_42');
 		$this->dbConnection = \OC::$server->getDatabaseConnection();
+		$this->customPropertiesService = new CustomPropertiesService($this->dbConnection);
 
 		$this->backend = new CustomPropertiesBackend(
 			$this->tree,
 			$this->dbConnection,
+			$this->customPropertiesService,
 			$this->user
 		);
 	}
@@ -123,9 +130,11 @@ class CustomPropertiesBackendTest extends TestCase {
 
 	public function testPropFindNoDbCalls() {
 		$db = $this->createMock(IDBConnection::class);
+		$service = new CustomPropertiesService($db);
 		$backend = new CustomPropertiesBackend(
 			$this->tree,
 			$db,
+			$service,
 			$this->user
 		);
 

build/psalm-baseline.xml

@@ -970,6 +970,11 @@
       <code>null</code>
     </NullArgument>
   </file>
+  <file src="apps/dav/lib/Upload/ChunkingV2Plugin.php">
+    <UndefinedFunction occurrences="1">
+      <code>Uri\split($destination)</code>
+    </UndefinedFunction>
+  </file>
   <file src="apps/dav/lib/Upload/UploadHome.php">
     <UndefinedFunction occurrences="1">
       <code>\Sabre\Uri\split($this-&gt;principalInfo['uri'])</code>

lib/composer/composer/autoload_classmap.php

@@ -294,6 +294,7 @@ return array(
     'OCP\\Files\\Notify\\INotifyHandler' => $baseDir . '/lib/public/Files/Notify/INotifyHandler.php',
     'OCP\\Files\\Notify\\IRenameChange' => $baseDir . '/lib/public/Files/Notify/IRenameChange.php',
     'OCP\\Files\\ObjectStore\\IObjectStore' => $baseDir . '/lib/public/Files/ObjectStore/IObjectStore.php',
+    'OCP\\Files\\ObjectStore\\IObjectStoreMultiPartUpload' => $baseDir . '/lib/public/Files/ObjectStore/IObjectStoreMultiPartUpload.php',
     'OCP\\Files\\ReservedWordException' => $baseDir . '/lib/public/Files/ReservedWordException.php',
     'OCP\\Files\\Search\\ISearchBinaryOperator' => $baseDir . '/lib/public/Files/Search/ISearchBinaryOperator.php',
     'OCP\\Files\\Search\\ISearchComparison' => $baseDir . '/lib/public/Files/Search/ISearchComparison.php',
@@ -311,6 +312,7 @@ return array(
     'OCP\\Files\\StorageInvalidException' => $baseDir . '/lib/public/Files/StorageInvalidException.php',
     'OCP\\Files\\StorageNotAvailableException' => $baseDir . '/lib/public/Files/StorageNotAvailableException.php',
     'OCP\\Files\\StorageTimeoutException' => $baseDir . '/lib/public/Files/StorageTimeoutException.php',
+    'OCP\\Files\\Storage\\IChunkedFileWrite' => $baseDir . '/lib/public/Files/Storage/IChunkedFileWrite.php',
     'OCP\\Files\\Storage\\IDisableEncryptionStorage' => $baseDir . '/lib/public/Files/Storage/IDisableEncryptionStorage.php',
     'OCP\\Files\\Storage\\ILockingStorage' => $baseDir . '/lib/public/Files/Storage/ILockingStorage.php',
     'OCP\\Files\\Storage\\INotifyStorage' => $baseDir . '/lib/public/Files/Storage/INotifyStorage.php',

lib/composer/composer/autoload_static.php

@@ -323,6 +323,7 @@ class ComposerStaticInit53792487c5a8370acc0b06b1a864ff4c
         'OCP\\Files\\Notify\\INotifyHandler' => __DIR__ . '/../../..' . '/lib/public/Files/Notify/INotifyHandler.php',
         'OCP\\Files\\Notify\\IRenameChange' => __DIR__ . '/../../..' . '/lib/public/Files/Notify/IRenameChange.php',
         'OCP\\Files\\ObjectStore\\IObjectStore' => __DIR__ . '/../../..' . '/lib/public/Files/ObjectStore/IObjectStore.php',
+        'OCP\\Files\\ObjectStore\\IObjectStoreMultiPartUpload' => __DIR__ . '/../../..' . '/lib/public/Files/ObjectStore/IObjectStoreMultiPartUpload.php',
         'OCP\\Files\\ReservedWordException' => __DIR__ . '/../../..' . '/lib/public/Files/ReservedWordException.php',
         'OCP\\Files\\Search\\ISearchBinaryOperator' => __DIR__ . '/../../..' . '/lib/public/Files/Search/ISearchBinaryOperator.php',
         'OCP\\Files\\Search\\ISearchComparison' => __DIR__ . '/../../..' . '/lib/public/Files/Search/ISearchComparison.php',
@@ -340,6 +341,7 @@ class ComposerStaticInit53792487c5a8370acc0b06b1a864ff4c
         'OCP\\Files\\StorageInvalidException' => __DIR__ . '/../../..' . '/lib/public/Files/StorageInvalidException.php',
         'OCP\\Files\\StorageNotAvailableException' => __DIR__ . '/../../..' . '/lib/public/Files/StorageNotAvailableException.php',
         'OCP\\Files\\StorageTimeoutException' => __DIR__ . '/../../..' . '/lib/public/Files/StorageTimeoutException.php',
+        'OCP\\Files\\Storage\\IChunkedFileWrite' => __DIR__ . '/../../..' . '/lib/public/Files/Storage/IChunkedFileWrite.php',
         'OCP\\Files\\Storage\\IDisableEncryptionStorage' => __DIR__ . '/../../..' . '/lib/public/Files/Storage/IDisableEncryptionStorage.php',
         'OCP\\Files\\Storage\\ILockingStorage' => __DIR__ . '/../../..' . '/lib/public/Files/Storage/ILockingStorage.php',
         'OCP\\Files\\Storage\\INotifyStorage' => __DIR__ . '/../../..' . '/lib/public/Files/Storage/INotifyStorage.php',

lib/private/Files/ObjectStore/ObjectStoreStorage.php

@@ -30,19 +30,27 @@
 
 namespace OC\Files\ObjectStore;
 
+use Aws\S3\Exception\S3Exception;
+use Aws\S3\Exception\S3MultipartUploadException;
 use Icewind\Streams\CallbackWrapper;
 use Icewind\Streams\CountWrapper;
 use Icewind\Streams\IteratorDirectory;
 use OC\Files\Cache\Cache;
 use OC\Files\Cache\CacheEntry;
 use OC\Files\Storage\PolyFill\CopyDirectory;
+use OC\Memcache\ArrayCache;
+use OC\Memcache\NullCache;
 use OCP\Files\Cache\ICacheEntry;
 use OCP\Files\FileInfo;
+use OCP\Files\GenericFileException;
 use OCP\Files\NotFoundException;
 use OCP\Files\ObjectStore\IObjectStore;
+use OCP\Files\ObjectStore\IObjectStoreMultiPartUpload;
+use OCP\Files\Storage\IChunkedFileWrite;
 use OCP\Files\Storage\IStorage;
+use OCP\ICache;
 
-class ObjectStoreStorage extends \OC\Files\Storage\Common {
+class ObjectStoreStorage extends \OC\Files\Storage\Common implements IChunkedFileWrite {
 	use CopyDirectory;
 
 	/**
@@ -62,6 +70,9 @@ class ObjectStoreStorage extends \OC\Files\Storage\Common {
 
 	private $logger;
 
+	/** @var ICache */
+	private $uploadCache;
+
 	public function __construct($params) {
 		if (isset($params['objectstore']) && $params['objectstore'] instanceof IObjectStore) {
 			$this->objectStore = $params['objectstore'];
@@ -82,11 +93,11 @@ class ObjectStoreStorage extends \OC\Files\Storage\Common {
 		}
 
 		$this->logger = \OC::$server->getLogger();
+		$this->uploadCache = \OC::$server->getMemCacheFactory()->createDistributed('objectstore');
 	}
 
 	public function mkdir($path) {
 		$path = $this->normalizePath($path);
-
 		if ($this->file_exists($path)) {
 			return false;
 		}
@@ -598,4 +609,103 @@ class ObjectStoreStorage extends \OC\Files\Storage\Common {
 			throw $e;
 		}
 	}
+
+	public function beginChunkedFile(string $targetPath): string {
+		$this->validateUploadCache();
+		if (!$this->objectStore instanceof IObjectStoreMultiPartUpload) {
+			throw new GenericFileException('Object store does not support multipart upload');
+		}
+		$cacheEntry = $this->getCache()->get($targetPath);
+		$urn = $this->getURN($cacheEntry->getId());
+		$uploadId = $this->objectStore->initiateMultipartUpload($urn);
+		$this->uploadCache->set($this->getUploadCacheKey($urn, $uploadId, 'uploadId'), $uploadId);
+		return $uploadId;
+	}
+
+	/**
+	 *
+	 * @throws GenericFileException
+	 */
+	public function putChunkedFilePart(string $targetPath, string $writeToken, string $chunkId, $data, $size = null): void {
+		$this->validateUploadCache();
+		if (!$this->objectStore instanceof IObjectStoreMultiPartUpload) {
+			throw new GenericFileException('Object store does not support multipart upload');
+		}
+		$cacheEntry = $this->getCache()->get($targetPath);
+		$urn = $this->getURN($cacheEntry->getId());
+		$uploadId = $this->uploadCache->get($this->getUploadCacheKey($urn, $writeToken, 'uploadId'));
+
+		$result = $this->objectStore->uploadMultipartPart($urn, $uploadId, (int)$chunkId, $data, $size);
+
+		$parts = $this->uploadCache->get($this->getUploadCacheKey($urn, $uploadId, 'parts'));
+		if (!$parts) {
+			$parts = [];
+		}
+		$parts[$chunkId] = [
+			'PartNumber' => $chunkId,
+			'ETag' => trim($result->get('ETag'), '"')
+		];
+		$this->uploadCache->set($this->getUploadCacheKey($urn, $uploadId, 'parts'), $parts);
+	}
+
+	public function writeChunkedFile(string $targetPath, string $writeToken): int {
+		$this->validateUploadCache();
+		if (!$this->objectStore instanceof IObjectStoreMultiPartUpload) {
+			throw new GenericFileException('Object store does not support multipart upload');
+		}
+		$cacheEntry = $this->getCache()->get($targetPath);
+		$urn = $this->getURN($cacheEntry->getId());
+		$uploadId = $this->uploadCache->get($this->getUploadCacheKey($urn, $writeToken, 'uploadId'));
+		$parts = $this->uploadCache->get($this->getUploadCacheKey($urn, $uploadId, 'parts'));
+		try {
+			$size = $this->objectStore->completeMultipartUpload($urn, $uploadId, array_values($parts));
+			$stat = $this->stat($targetPath);
+			$mtime = time();
+			if (is_array($stat)) {
+				$stat['size'] = $size;
+				$stat['mtime'] = $mtime;
+				$stat['mimetype'] = $this->getMimeType($targetPath);
+				$this->getCache()->update($stat['fileid'], $stat);
+			}
+		} catch (S3MultipartUploadException | S3Exception $e) {
+			$this->objectStore->abortMultipartUpload($urn, $uploadId);
+			$this->logger->logException($e, [
+				'app' => 'objectstore',
+				'message' => 'Could not compete multipart upload ' . $urn. ' with uploadId ' . $uploadId
+			]);
+			throw new GenericFileException('Could not write chunked file');
+		} finally {
+			$this->clearCache($urn, $uploadId);
+		}
+		return $size;
+	}
+
+	public function cancelChunkedFile(string $targetPath, string $writeToken): void {
+		$this->validateUploadCache();
+		if (!$this->objectStore instanceof IObjectStoreMultiPartUpload) {
+			throw new GenericFileException('Object store does not support multipart upload');
+		}
+		$cacheEntry = $this->getCache()->get($targetPath);
+		$urn = $this->getURN($cacheEntry->getId());
+		$uploadId = $this->uploadCache->get($this->getUploadCacheKey($urn, $writeToken, 'uploadId'));
+		$this->objectStore->abortMultipartUpload($urn, $uploadId);
+		$this->clearCache($urn, $uploadId);
+	}
+
+	/**
+	 * @throws GenericFileException
+	 */
+	private function validateUploadCache(): void {
+		if ($this->uploadCache instanceof NullCache || $this->uploadCache instanceof ArrayCache) {
+			throw new GenericFileException('ChunkedFileWrite not available: A cross-request persistent cache is required');
+		}
+	}
+
+	private function getUploadCacheKey($urn, $uploadId, $chunkId = null): string {
+		return $urn . '-' . $uploadId . '-' . ($chunkId ? $chunkId . '-' : '');
+	}
+
+	private function clearCache($urn, $uploadId): void {
+		$this->uploadCache->clear($this->getUploadCacheKey($urn, $uploadId));
+	}
 }

lib/private/Files/ObjectStore/S3.php

@@ -24,9 +24,12 @@
 
 namespace OC\Files\ObjectStore;
 
+use Aws\Result;
+use Exception;
 use OCP\Files\ObjectStore\IObjectStore;
+use OCP\Files\ObjectStore\IObjectStoreMultiPartUpload;
 
-class S3 implements IObjectStore {
+class S3 implements IObjectStore, IObjectStoreMultiPartUpload {
 	use S3ConnectionTrait;
 	use S3ObjectTrait;
 
@@ -41,4 +44,49 @@ class S3 implements IObjectStore {
 	public function getStorageId() {
 		return $this->id;
 	}
+
+	public function initiateMultipartUpload(string $urn): string {
+		$upload = $this->getConnection()->createMultipartUpload([
+			'Bucket' => $this->bucket,
+			'Key' => $urn,
+		] + $this->getSseKmsPutParameters());
+		$uploadId = $upload->get('UploadId');
+		if ($uploadId === null) {
+			throw new Exception('No upload id returned');
+		}
+		return (string)$uploadId;
+	}
+
+	public function uploadMultipartPart(string $urn, string $uploadId, int $partId, $stream, $size): Result {
+		return $this->getConnection()->uploadPart([
+			'Body' => $stream,
+			'Bucket' => $this->bucket,
+			'Key' => $urn,
+			'ContentLength' => $size,
+			'PartNumber' => $partId,
+			'UploadId' => $uploadId,
+		]);
+	}
+
+	public function completeMultipartUpload(string $urn, string $uploadId, array $result): int {
+		$this->getConnection()->completeMultipartUpload([
+			'Bucket' => $this->bucket,
+			'Key' => $urn,
+			'UploadId' => $uploadId,
+			'MultipartUpload' => ['Parts' => $result],
+		] + $this->getSseKmsPutParameters());
+		$stat = $this->getConnection()->headObject([
+			'Bucket' => $this->bucket,
+			'Key' => $urn,
+		]);
+		return (int)$stat->get('ContentLength');
+	}
+
+	public function abortMultipartUpload($urn, $uploadId): void {
+		$this->getConnection()->abortMultipartUpload([
+			'Bucket' => $this->bucket,
+			'Key' => $urn,
+			'UploadId' => $uploadId
+		]);
+	}
 }

lib/private/Files/ObjectStore/S3ConnectionTrait.php

@@ -1,7 +1,6 @@
 <?php
 /**
  * @copyright Copyright (c) 2016 Robin Appelman <robin@icewind.nl>
- *
  * @author Arthur Schiwon <blizzz@arthur-schiwon.de>
  * @author Christoph Wurst <christoph@winzerhof-wurst.at>
  * @author Florent <florent@coppint.com>
@@ -10,7 +9,6 @@
  * @author Roeland Jago Douma <roeland@famdouma.nl>
  * @author S. Cat <33800996+sparrowjack63@users.noreply.github.com>
  * @author Stephen Cuppett <steve@cuppett.com>
- *
  * @license GNU AGPL version 3 or any later version
  *
  * This program is free software: you can redistribute it and/or modify
@@ -25,15 +23,14 @@
  *
  * 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\Files\ObjectStore;
 
 use Aws\ClientResolver;
 use Aws\Credentials\CredentialProvider;
-use Aws\Credentials\EcsCredentialProvider;
 use Aws\Credentials\Credentials;
+use Aws\Credentials\EcsCredentialProvider;
 use Aws\Exception\CredentialsException;
 use Aws\S3\Exception\S3Exception;
 use Aws\S3\S3Client;
@@ -41,6 +38,7 @@ use GuzzleHttp\Promise;
 use GuzzleHttp\Promise\RejectedPromise;
 use OCP\ILogger;
 
+
 trait S3ConnectionTrait {
 	/** @var array */
 	protected $params;
@@ -60,11 +58,17 @@ trait S3ConnectionTrait {
 	/** @var int */
 	protected $uploadPartSize;
 
+	/** @var string */
+	protected $sseKmsKeyId;
+
+	/** @var bool */
+	protected $sseUseBucketKey;
+
 	protected $test;
 
 	protected function parseParams($params) {
 		if (empty($params['bucket'])) {
-			throw new \Exception("Bucket has to be configured.");
+			throw new \Exception('Bucket has to be configured.');
 		}
 
 		$this->id = 'amazon::' . $params['bucket'];
@@ -78,7 +82,14 @@ trait S3ConnectionTrait {
 		if (!isset($params['port']) || $params['port'] === '') {
 			$params['port'] = (isset($params['use_ssl']) && $params['use_ssl'] === false) ? 80 : 443;
 		}
-		$params['verify_bucket_exists'] = empty($params['verify_bucket_exists']) ? true : $params['verify_bucket_exists'];
+		$params['autocreate'] = !isset($params['autocreate']) ? false : $params['autocreate'];
+
+		// this avoid at least the hash lookups for each read/weite operation
+		if (isset($params['ssekmskeyid'])) {
+			$this->sseKmsKeyId = $params['ssekmskeyid'];
+		}
+		$this->sseUseBucketKey = (isset($params['sseusebucketkey'])) ? $params['sseusebucketkey'] : false;
+
 		$this->params = $params;
 	}
 
@@ -87,9 +98,122 @@ trait S3ConnectionTrait {
 	}
 
 	/**
-	 * Returns the connection
+	 * Add the SSE KMS parameterdepending on the
+	 * KMS encryption strategy (bucket, individual or
+	 * no encryption) for object creations.
+	 *
+	 * @return array with encryption parameters
+	 */
+	public function getSseKmsPutParameters(): array {
+		if ($this->sseUseBucketKey) {
+			return [
+				'ServerSideEncryption' => 'aws:kms',
+				'BucketKeyEnabled' => true,
+			];
+		} elseif (!empty($this->sseKmsKeyId)) {
+			return [
+				'ServerSideEncryption' => 'aws:kms',
+				'BucketKeyEnabled' => false,
+				'SSEKMSKeyId' => $this->sseKmsKeyId,
+			];
+		} else {
+			return [];
+		}
+	}
+
+	/**
+	 * Add the SSE KMS parameter depending on the
+	 * KMS encryption strategy (bucket, individual or
+	 * no encryption) for object read.
+	 *
+	 * @return array with encryption parameters
+	 */
+	public function getSseKmsGetParameters(): array {
+		if (($this->sseUseBucketKey) || !empty($this->sseKmsKeyId)) {
+			return [
+				'ServerSideEncryption' => 'aws:kms',
+			];
+		} else {
+			return [];
+		}
+	}
+
+	/**
+	 * Create the required bucket
+	 *
+	 * @throws \Exception if bucket creation fails
+	 */
+	protected function createNewBucket() {
+		$logger = \OC::$server->getLogger();
+		try {
+			$logger->info('Bucket "'.$this->bucket.'" does not exist - creating it.', ['app' => 'objectstore']);
+			if (!$this->connection::isBucketDnsCompatible($this->bucket)) {
+				throw new \Exception('The bucket will not be created because the name is not dns compatible, please correct it: '.$this->bucket);
+			}
+			$this->connection->createBucket(['Bucket' => $this->bucket]);
+			$this->testTimeout();
+		} catch (S3Exception $e) {
+			$logger->logException($e, [
+				'message' => 'Invalid remote storage.',
+				'level' => ILogger::DEBUG,
+				'app' => 'objectstore',
+			]);
+			throw new \Exception('Creation of bucket "'.$this->bucket.'" failed. '.$e->getMessage());
+		}
+	}
+
+	/**
+	 * Check bucket key consistency or put bucket key if missing
+	 * This operation only works for bucket owner or with
+	 * s3:GetEncryptionConfiguration/s3:PutEncryptionConfiguration permission
+	 *
+	 * We recommend to use autocreate only on initial setup and
+	 * use an S3:user only with object operation permission and no bucket operation permissions
+	 * later with autocreate=false
+	 *
+	 * @throws \Exception if bucket key config is inconsistent or if putting the key fails
+	 */
+	protected function checkOrPutBucketKey() {
+		$logger = \OC::$server->getLogger();
+
+		try {
+			$encrypt_state = $this->connection->getBucketEncryption([
+				'Bucket' => $this->bucket,
+			]);
+		} catch (S3Exception $e) {
+			try {
+				$logger->info('Bucket key for "'.$this->bucket.'" is not set - adding it.', ['app' => 'objectstore']);
+				$this->connection->putBucketEncryption([
+					'Bucket' => $this->bucket,
+					'ServerSideEncryptionConfiguration' => [
+						'Rules' => [
+							[
+								'ApplyServerSideEncryptionByDefault' => [
+									'SSEAlgorithm' => 'aws:kms',
+									'KMSMasterKeyID' => $this->sseKmsKeyId,
+								],
+							],
+						],
+					],
+				]);
+				$this->testTimeout();
+			} catch (S3Exception $e) {
+				$logger->logException($e, [
+					'message' => 'Bucket key problem.',
+					'level' => ILogger::DEBUG,
+					'app' => 'objectstore',
+				]);
+				throw new \Exception('Putting configured bucket key to "'.$this->bucket.'" failed. '.$e->getMessage());
+			}
+		}
+	}
+
+
+	/**
+	 * Returns the connection.
 	 *
 	 * @return S3Client connected client
+	 *
 	 * @throws \Exception if connection could not be made
 	 */
 	public function getConnection() {
@@ -98,7 +222,7 @@ trait S3ConnectionTrait {
 		}
 
 		$scheme = (isset($this->params['use_ssl']) && $this->params['use_ssl'] === false) ? 'http' : 'https';
-		$base_url = $scheme . '://' . $this->params['hostname'] . ':' . $this->params['port'] . '/';
+		$base_url = $scheme.'://'.$this->params['hostname'].':'.$this->params['port'].'/';
 
 		// Adding explicit credential provider to the beginning chain.
 		// Including environment variables and IAM instance profiles.
@@ -121,6 +245,7 @@ trait S3ConnectionTrait {
 			'use_path_style_endpoint' => isset($this->params['use_path_style']) ? $this->params['use_path_style'] : false,
 			'signature_provider' => \Aws\or_chain([self::class, 'legacySignatureProvider'], ClientResolver::_default_signature_provider()),
 			'csm' => false,
+			// 'debug'   => true, // to debug S3 communication
 		];
 		if (isset($this->params['proxy'])) {
 			$options['request.options'] = ['proxy' => $this->params['proxy']];
@@ -132,27 +257,16 @@ trait S3ConnectionTrait {
 
 		if (!$this->connection::isBucketDnsCompatible($this->bucket)) {
 			$logger = \OC::$server->getLogger();
-			$logger->debug('Bucket "' . $this->bucket . '" This bucket name is not dns compatible, it may contain invalid characters.',
-					 ['app' => 'objectstore']);
+			$logger->debug('Bucket "' . $this->bucket.'" This bucket name is not dns compatible, it may contain invalid characters.',
+					['app' => 'objectstore']);
 		}
 
-		if ($this->params['verify_bucket_exists'] && !$this->connection->doesBucketExist($this->bucket)) {
-			$logger = \OC::$server->getLogger();
-			try {
-				$logger->info('Bucket "' . $this->bucket . '" does not exist - creating it.', ['app' => 'objectstore']);
-				if (!$this->connection::isBucketDnsCompatible($this->bucket)) {
-					throw new \Exception("The bucket will not be created because the name is not dns compatible, please correct it: " . $this->bucket);
-				}
-				$this->connection->createBucket(['Bucket' => $this->bucket]);
-				$this->testTimeout();
-			} catch (S3Exception $e) {
-				$logger->logException($e, [
-					'message' => 'Invalid remote storage.',
-					'level' => ILogger::DEBUG,
-					'app' => 'objectstore',
-				]);
-				throw new \Exception('Creation of bucket "' . $this->bucket . '" failed. ' . $e->getMessage());
-			}
+		if ($this->params['autocreate'] && !$this->connection->doesBucketExist($this->bucket)) {
+			$this->createNewBucket();
+		}
+
+		if ($this->params['autocreate'] && $this->sseUseBucketKey) {
+			$this->checkOrPutBucketKey();
 		}
 
 		// google cloud's s3 compatibility doesn't like the EncodingType parameter
@@ -164,7 +278,7 @@ trait S3ConnectionTrait {
 	}
 
 	/**
-	 * when running the tests wait to let the buckets catch up
+	 * when running the tests wait to let the buckets catch up.
 	 */
 	private function testTimeout() {
 		if ($this->test) {
@@ -183,9 +297,9 @@ trait S3ConnectionTrait {
 	}
 
 	/**
-	 * This function creates a credential provider based on user parameter file
+	 * This function creates a credential provider based on user parameter file.
 	 */
-	protected function paramCredentialProvider() : callable {
+	protected function paramCredentialProvider(): callable {
 		return function () {
 			$key = empty($this->params['key']) ? null : $this->params['key'];
 			$secret = empty($this->params['secret']) ? null : $this->params['secret'];
@@ -197,6 +311,7 @@ trait S3ConnectionTrait {
 			}
 
 			$msg = 'Could not find parameters set for credentials in config file.';
+
 			return new RejectedPromise(new CredentialsException($msg));
 		};
 	}

lib/private/Files/ObjectStore/S3ObjectTrait.php

@@ -1,13 +1,11 @@
 <?php
 /**
  * @copyright Copyright (c) 2017 Robin Appelman <robin@icewind.nl>
- *
  * @author Christoph Wurst <christoph@winzerhof-wurst.at>
  * @author Florent <florent@coppint.com>
  * @author Morris Jobke <hey@morrisjobke.de>
  * @author Robin Appelman <robin@icewind.nl>
  * @author Roeland Jago Douma <roeland@famdouma.nl>
- *
  * @license GNU AGPL version 3 or any later version
  *
  * This program is free software: you can redistribute it and/or modify
@@ -22,7 +20,6 @@
  *
  * 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\Files\ObjectStore;
@@ -31,75 +28,114 @@ use Aws\S3\Exception\S3MultipartUploadException;
 use Aws\S3\MultipartUploader;
 use Aws\S3\ObjectUploader;
 use Aws\S3\S3Client;
+use GuzzleHttp\Psr7\CachingStream;
 use Icewind\Streams\CallbackWrapper;
 use OC\Files\Stream\SeekableHttpStream;
 
-trait S3ObjectTrait {
-	/**
-	 * Returns the connection
-	 *
-	 * @return S3Client connected client
-	 * @throws \Exception if connection could not be made
-	 */
-	abstract protected function getConnection();
+trait S3ObjectTrait
+{
+    /**
+     * Returns the connection.
+     *
+     * @return S3Client connected client
+     *
+     * @throws \Exception if connection could not be made
+     */
+    abstract protected function getConnection();
 
-	/**
-	 * @param string $urn the unified resource name used to identify the object
-	 * @return resource stream with the read data
-	 * @throws \Exception when something goes wrong, message will be logged
-	 * @since 7.0.0
-	 */
-	public function readObject($urn) {
-		return SeekableHttpStream::open(function ($range) use ($urn) {
-			$command = $this->getConnection()->getCommand('GetObject', [
-				'Bucket' => $this->bucket,
-				'Key' => $urn,
-				'Range' => 'bytes=' . $range,
-			]);
-			$request = \Aws\serialize($command);
-			$headers = [];
-			foreach ($request->getHeaders() as $key => $values) {
-				foreach ($values as $value) {
-					$headers[] = "$key: $value";
-				}
-			}
-			$opts = [
-				'http' => [
-					'protocol_version' => 1.1,
-					'header' => $headers,
-				],
-			];
+    /* compute configured encryption headers for put operations */
+    abstract protected function getSseKmsPutParameters();
 
-			$context = stream_context_create($opts);
-			return fopen($request->getUri(), 'r', false, $context);
-		});
-	}
+    /* compute configured encryption headers for get operations */
+    abstract protected function getSseKmsGetParameters();
 
-	/**
-	 * @param string $urn the unified resource name used to identify the object
-	 * @param resource $stream stream with the data to write
-	 * @param string|null $mimetype the mimetype to set for the remove object @since 22.0.0
-	 * @throws \Exception when something goes wrong, message will be logged
-	 * @since 7.0.0
-	 */
-	public function writeObject($urn, $stream, string $mimetype = null) {
-		$count = 0;
-		$countStream = CallbackWrapper::wrap($stream, function ($read) use (&$count) {
-			$count += $read;
-		});
+    /**
+     * @param string $urn the unified resource name used to identify the object
+     *
+     * @return resource stream with the read data
+     *
+     * @throws \Exception when something goes wrong, message will be logged
+     *
+     * @since 7.0.0
+     */
+    public function readObject($urn)
+    {
+        return SeekableHttpStream::open(function ($range) use ($urn) {
+            $s3params = [
+                'Bucket' => $this->bucket,
+                'Key' => $urn,
+                'Range' => 'bytes='.$range,
+            ] + $this->getSseKmsGetParameters();
+            $command = $this->getConnection()->getCommand('GetObject', $s3params);
+            $request = \Aws\serialize($command);
+            $headers = [];
+            foreach ($request->getHeaders() as $key => $values) {
+                foreach ($values as $value) {
+                    $headers[] = "$key: $value";
+                }
+            }
+            $opts = [
+                'http' => [
+                    'protocol_version' => 1.1,
+                    'header' => $headers,
+                ],
+            ];
 
-		$uploader = new MultipartUploader($this->getConnection(), $countStream, [
-			'bucket' => $this->bucket,
-			'key' => $urn,
-			'part_size' => $this->uploadPartSize,
-			'params' => [
-				'ContentType' => $mimetype
-			]
-		]);
+            $context = stream_context_create($opts);
+
+            return fopen($request->getUri(), 'r', false, $context);
+        });
+    }
+
+    /**
+     * @param string $urn the unified resource name used to identify the object
+     * @param resource $stream stream with the data to write
+     * @param string|null $mimetype the mimetype to set for the remove object @since 22.0.0
+     * @throws \Exception when something goes wrong, message will be logged
+     * @since 7.0.0
+     */
+    public function writeObject($urn, $stream, string $mimetype = null)
+    {
+        //$streamMeta = stream_get_meta_data($stream);
+        //if ($streamMeta['seekable']) {
+            // the ObjectUploader requires the stream seekable for objects <5MB 
+            // to copute checksum before uploading
+            //$stream = new CachingStream($stream);
+        //}
+        $count = 0;
+        $countStream = CallbackWrapper::wrap($stream, function ($read) use (&$count) {
+            $count += $read;
+        });
+
+        $s3params = [
+            'bucket' => $this->bucket,
+            'key' => $urn,
+            'part_size' => $this->uploadPartSize,
+            'params' => [
+                'ContentType' => $mimetype
+            ] + $this->getSseKmsPutParameters(),
+        ];
+
+        // ObjectUplader version
+        //$s3params = [
+        //    'part_size' => $this->uploadPartSize,
+        //    'params' => [
+        //        'ContentType' => $mimetype
+        //    ] + $this->getSseKmsPutParameters(),
+        //];
+
+        // maybe, we should also use ObjectUploader here in the future
+        // it does direct uploads for small files < 5MB and multipart otherwise
+        //$uploader = new ObjectUploader($this->getConnection(), $this->bucket, $urn, $countStream, 'private', $s3params);
+        $uploader = new MultipartUploader($this->getConnection(), $countStream, $s3params);
+
+        try {
+            $uploader->upload();
+        } catch (S3MultipartUploadException $e) {
+            // if anything goes wrong with multipart, make sure that you don´t poison and 
+            // slow down s3 bucket with fragment management
+            $this->getConnection()->abortMultipartUpload($uploader->getState()->getId());
 
-		try {
-			$uploader->upload();
-		} catch (S3MultipartUploadException $e) {
 			// This is an empty file so just touch it then
 			if ($count === 0 && feof($countStream)) {
 				$uploader = new ObjectUploader($this->getConnection(), $this->bucket, $urn, '');
@@ -107,27 +143,46 @@ trait S3ObjectTrait {
 			} else {
 				throw $e;
 			}
-		}
-	}
+        } 
+        //finally {
+            // this handles [S3] fclose(): supplied resource is not a valid stream resource #23373
+            // see https://stackoverflow.com/questions/11247507/fclose-18-is-not-a-valid-stream-resource/11247555
+            // which also recommends the solution
+        //    if (is_resource($stream)) {
+        //        fclose($stream);
+        //    }
+        //}
+    }
 
-	/**
-	 * @param string $urn the unified resource name used to identify the object
-	 * @return void
-	 * @throws \Exception when something goes wrong, message will be logged
-	 * @since 7.0.0
-	 */
-	public function deleteObject($urn) {
-		$this->getConnection()->deleteObject([
-			'Bucket' => $this->bucket,
-			'Key' => $urn,
-		]);
-	}
+    /**
+     * @param string $urn the unified resource name used to identify the object
+     *
+     * @return void
+     *
+     * @throws \Exception when something goes wrong, message will be logged
+     *
+     * @since 7.0.0
+     */
+    public function deleteObject($urn)
+    {
+        $this->getConnection()->deleteObject([
+            'Bucket' => $this->bucket,
+            'Key' => $urn,
+        ]);
+    }
 
-	public function objectExists($urn) {
-		return $this->getConnection()->doesObjectExist($this->bucket, $urn);
-	}
-
-	public function copyObject($from, $to) {
-		$this->getConnection()->copy($this->getBucket(), $from, $this->getBucket(), $to);
-	}
+    public function objectExists($urn)
+    {
+        return $this->getConnection()->doesObjectExist($this->bucket, $urn);
+    }
+    
+    /**
+     * S3 copy command with SSE KMS key handling.
+     */
+    public function copyObject($from, $to)
+    {
+        $this->getConnection()->copy($this->getBucket(), $from, $this->getBucket(), $to, 'private', [
+            'params' => $this->getSseKmsPutParameters(),
+        ]);
+    }
 }

lib/private/Files/View.php

@@ -62,7 +62,9 @@ use OCP\Files\InvalidPathException;
 use OCP\Files\Mount\IMountPoint;
 use OCP\Files\NotFoundException;
 use OCP\Files\ReservedWordException;
+use OCP\Files\Storage\IChunkedFileWrite;
 use OCP\Files\Storage\IStorage;
+use OCP\Files\StorageInvalidException;
 use OCP\ILogger;
 use OCP\IUser;
 use OCP\Lock\ILockingProvider;
@@ -704,6 +706,22 @@ class View {
 		}
 	}
 
+	/**
+	 * @param string $path
+	 * @param string $chunkToken
+	 * @return false|mixed|null
+	 * @throws LockedException
+	 * @throws StorageInvalidException
+	 */
+	public function writeChunkedFile(string $path, string $chunkToken) {
+		/** @var IStorage|null $storage */
+		[$storage, ] = Filesystem::resolvePath($path);
+		if (!$storage || !$storage->instanceOfStorage(IChunkedFileWrite::class)) {
+			throw new StorageInvalidException('path is not a chunked file write storage');
+		}
+		return $this->basicOperation('writeChunkedFile', $path, ['update', 'write'], $chunkToken);
+	}
+
 	/**
 	 * @param string $path
 	 * @return bool|mixed

lib/public/Files/ObjectStore/IObjectStoreMultiPartUpload.php

@@ -0,0 +1,54 @@
+<?php
+/*
+ * @copyright Copyright (c) 2021 Julius Härtl <jus@bitgrid.net>
+ *
+ * @author Julius Härtl <jus@bitgrid.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/>.
+ *
+ */
+
+declare(strict_types=1);
+
+
+namespace OCP\Files\ObjectStore;
+
+use Aws\Result;
+
+/**
+ * @since 22.0.0
+ */
+interface IObjectStoreMultiPartUpload {
+	/**
+	 * @since 22.0.0
+	 */
+	public function initiateMultipartUpload(string $urn): string;
+
+	/**
+	 * @since 22.0.0
+	 */
+	public function uploadMultipartPart(string $urn, string $uploadId, int $partId, $stream, $size): Result;
+
+	/**
+	 * @since 22.0.0
+	 */
+	public function completeMultipartUpload(string $urn, string $uploadId, array $result): int;
+
+	/**
+	 * @since 22.0.0
+	 */
+	public function abortMultipartUpload(string $urn, string $uploadId): void;
+}

lib/public/Files/Storage/IChunkedFileWrite.php

@@ -0,0 +1,71 @@
+<?php
+/*
+ * @copyright Copyright (c) 2021 Julius Härtl <jus@bitgrid.net>
+ *
+ * @author Julius Härtl <jus@bitgrid.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/>.
+ *
+ */
+
+declare(strict_types=1);
+
+
+namespace OCP\Files\Storage;
+
+use OCP\Files\GenericFileException;
+
+/**
+ * @since 22.0.0
+ */
+interface IChunkedFileWrite extends IStorage {
+
+	/**
+	 * @param string $targetPath Relative target path in the storage
+	 * @return string writeToken to be used with the other methods to uniquely identify the file write operation
+	 * @throws GenericFileException
+	 * @since 22.0.0
+	 */
+	public function beginChunkedFile(string $targetPath): string;
+
+	/**
+	 * @param string $targetPath
+	 * @param string $writeToken
+	 * @param string $chunkId
+	 * @param resource $data
+	 * @param int|null $size
+	 * @throws GenericFileException
+	 * @since 22.0.0
+	 */
+	public function putChunkedFilePart(string $targetPath, string $writeToken, string $chunkId, $data, int $size = null): void;
+
+	/**
+	 * @param string $targetPath
+	 * @param string $writeToken
+	 * @return int
+	 * @throws GenericFileException
+	 * @since 22.0.0
+	 */
+	public function writeChunkedFile(string $targetPath, string $writeToken): int;
+
+	/**
+	 * @param string $targetPath
+	 * @param string $writeToken
+	 * @throws GenericFileException
+	 * @since 22.0.0
+	 */
+	public function cancelChunkedFile(string $targetPath, string $writeToken): void;
+}

tests/lib/Files/ObjectStore/ObjectStoreTest.php

@@ -24,104 +24,115 @@ namespace Test\Files\ObjectStore;
 
 use Test\TestCase;
 
-abstract class ObjectStoreTest extends TestCase {
+abstract class ObjectStoreTest extends TestCase
+{
 
-	/**
-	 * @return \OCP\Files\ObjectStore\IObjectStore
-	 */
-	abstract protected function getInstance();
+    /**
+     * @return \OCP\Files\ObjectStore\IObjectStore
+     */
+    abstract protected function getInstance();
 
-	protected function stringToStream($data) {
-		$stream = fopen('php://temp', 'w+');
-		fwrite($stream, $data);
-		rewind($stream);
-		return $stream;
-	}
+    protected function stringToStream($data)
+    {
+        $stream = fopen('php://temp', 'w+');
+        fwrite($stream, $data);
+        rewind($stream);
+        return $stream;
+    }
 
-	public function testWriteRead() {
-		$stream = $this->stringToStream('foobar');
+    public function testWriteRead()
+    {
+        $stream = $this->stringToStream('foobar');
 
-		$instance = $this->getInstance();
+        $instance = $this->getInstance();
 
-		$instance->writeObject('1', $stream);
+        $instance->writeObject('1', $stream);
 
-		$result = $instance->readObject('1');
-		$instance->deleteObject('1');
+        $result = $instance->readObject('1');
+        $instance->deleteObject('1');
 
-		$this->assertEquals('foobar', stream_get_contents($result));
-	}
+        $this->assertEquals('foobar', stream_get_contents($result));
+    }
 
-	public function testDelete() {
-		$stream = $this->stringToStream('foobar');
+    public function testDelete()
+    {
+        $stream = $this->stringToStream('foobar');
 
-		$instance = $this->getInstance();
+        $instance = $this->getInstance();
 
-		$instance->writeObject('2', $stream);
+        $instance->writeObject('2', $stream);
 
-		$instance->deleteObject('2');
+        $instance->deleteObject('2');
 
-		try {
-			// to to read to verify that the object no longer exists
-			$instance->readObject('2');
-			$this->fail();
-		} catch (\Exception $e) {
-			// dummy assert to keep phpunit happy
-			$this->assertEquals(1, 1);
-		}
-	}
+        try {
+            // to to read to verify that the object no longer exists
+            $instance->readObject('2');
+            $this->fail();
+        } catch (\Exception $e) {
+            // dummy assert to keep phpunit happy
+            $this->assertEquals(1, 1);
+        }
+    }
 
-	public function testReadNonExisting() {
-		$instance = $this->getInstance();
+    public function testReadNonExisting()
+    {
+        $instance = $this->getInstance();
 
-		try {
-			$instance->readObject('non-existing');
-			$this->fail();
-		} catch (\Exception $e) {
-			// dummy assert to keep phpunit happy
-			$this->assertEquals(1, 1);
-		}
-	}
+        try {
+            $instance->readObject('non-existing');
+            $this->fail();
+        } catch (\Exception $e) {
+            // dummy assert to keep phpunit happy
+            $this->assertEquals(1, 1);
+        }
+    }
 
-	public function testDeleteNonExisting() {
-		$instance = $this->getInstance();
+    public function testDeleteNonExisting()
+    {
+        $instance = $this->getInstance();
 
-		try {
-			$instance->deleteObject('non-existing');
-			$this->fail();
-		} catch (\Exception $e) {
-			// dummy assert to keep phpunit happy
-			$this->assertEquals(1, 1);
-		}
-	}
+        try {
+            $instance->deleteObject('non-existing');
+            $this->fail();
+        } catch (\Exception $e) {
+            // dummy assert to keep phpunit happy
+            $this->assertEquals(1, 1);
+        }
+    }
 
-	public function testExists() {
-		$stream = $this->stringToStream('foobar');
+    public function testExists()
+    {
+        $stream = $this->stringToStream('foobar');
 
-		$instance = $this->getInstance();
-		$this->assertFalse($instance->objectExists('2'));
+        $instance = $this->getInstance();
+        $this->assertFalse($instance->objectExists('2'));
 
-		$instance->writeObject('2', $stream);
+        $instance->writeObject('2', $stream);
 
-		$this->assertTrue($instance->objectExists('2'));
+        $this->assertTrue($instance->objectExists('2'));
 
-		$instance->deleteObject('2');
+        $instance->deleteObject('2');
 
-		$this->assertFalse($instance->objectExists('2'));
-	}
+        $this->assertFalse($instance->objectExists('2'));
+    }
 
-	public function testCopy() {
-		$stream = $this->stringToStream('foobar');
+    public function testCopy()
+    {
+        $stream = $this->stringToStream('foobar');
 
-		$instance = $this->getInstance();
+        $instance = $this->getInstance();
 
-		$instance->writeObject('source', $stream);
+        $instance->writeObject('source', $stream);
 
-		$this->assertFalse($instance->objectExists('target'));
+        $this->assertFalse($instance->objectExists('target'));
 
-		$instance->copyObject('source', 'target');
+        $instance->copyObject('source', 'target');
 
-		$this->assertTrue($instance->objectExists('target'));
+        $this->assertTrue($instance->objectExists('target'));
 
-		$this->assertEquals('foobar', stream_get_contents($instance->readObject('target')));
-	}
+        $this->assertEquals('foobar', stream_get_contents($instance->readObject('target')));
+
+        //$instance->deleteObject('source');
+        //$instance->deleteObject('target');
+    }
 }

tests/lib/Files/ObjectStore/S3Test.php

@@ -22,81 +22,126 @@
 namespace Test\Files\ObjectStore;
 
 use Icewind\Streams\Wrapper;
+use Icewind\Streams\CallbackWrapper;
 use OC\Files\ObjectStore\S3;
 
-class MultiPartUploadS3 extends S3 {
-	public function writeObject($urn, $stream, string $mimetype = null) {
-		$this->getConnection()->upload($this->bucket, $urn, $stream, 'private', [
-			'mup_threshold' => 1,
-		]);
-	}
+use Aws\S3\S3Client;
+use Aws\S3\Exception\S3MultipartUploadException;
+
+class MultiPartUploadS3 extends S3
+{
+    public function writeObject($urn, $stream, string $mimetype = null)
+    {
+        $this->getConnection()->upload($this->bucket, $urn, $stream, 'private', [
+            'mup_threshold' => 1,
+        ]);
+    }
 }
 
-class NonSeekableStream extends Wrapper {
-	public static function wrap($source) {
-		$context = stream_context_create([
-			'nonseek' => [
-				'source' => $source,
-			],
-		]);
-		return Wrapper::wrapSource($source, $context, 'nonseek', self::class);
-	}
+class NonSeekableStream extends Wrapper
+{
+    public static function wrap($source)
+    {
+        $context = stream_context_create([
+            'nonseek' => [
+                'source' => $source,
+            ],
+        ]);
+        return Wrapper::wrapSource($source, $context, 'nonseek', self::class);
+    }
 
-	public function dir_opendir($path, $options) {
-		return false;
-	}
+    public function dir_opendir($path, $options)
+    {
+        return false;
+    }
 
-	public function stream_open($path, $mode, $options, &$opened_path) {
-		$this->loadContext('nonseek');
-		return true;
-	}
+    public function stream_open($path, $mode, $options, &$opened_path)
+    {
+        $this->loadContext('nonseek');
+        return true;
+    }
 
-	public function stream_seek($offset, $whence = SEEK_SET) {
-		return false;
-	}
+    public function stream_seek($offset, $whence = SEEK_SET)
+    {
+        return false;
+    }
 }
 
 /**
  * @group PRIMARY-s3
  */
-class S3Test extends ObjectStoreTest {
-	protected function getInstance() {
-		$config = \OC::$server->getConfig()->getSystemValue('objectstore');
-		if (!is_array($config) || $config['class'] !== 'OC\\Files\\ObjectStore\\S3') {
-			$this->markTestSkipped('objectstore not configured for s3');
-		}
+class S3Test extends ObjectStoreTest
+{
+    protected function getInstance()
+    {
+        $config = \OC::$server->getConfig()->getSystemValue('objectstore');
+        if (!is_array($config) || $config['class'] !== '\\OC\\Files\\ObjectStore\\S3') {
+            $this->markTestSkipped('objectstore not configured for s3');
+        }
 
-		return new S3($config['arguments']);
-	}
+        return new S3($config['arguments']);
+    }
 
-	public function testUploadNonSeekable() {
-		$config = \OC::$server->getConfig()->getSystemValue('objectstore');
-		if (!is_array($config) || $config['class'] !== 'OC\\Files\\ObjectStore\\S3') {
-			$this->markTestSkipped('objectstore not configured for s3');
-		}
+    public function testUploadNonSeekable()
+    {
+        $s3 = $this->getInstance();
 
-		$s3 = $this->getInstance();
+        $s3->writeObject('multiparttest', NonSeekableStream::wrap(fopen(__FILE__, 'r')));
 
-		$s3->writeObject('multiparttest', NonSeekableStream::wrap(fopen(__FILE__, 'r')));
+        $result = $s3->readObject('multiparttest');
 
-		$result = $s3->readObject('multiparttest');
+        $this->assertEquals(file_get_contents(__FILE__), stream_get_contents($result));
 
-		$this->assertEquals(file_get_contents(__FILE__), stream_get_contents($result));
-	}
+        $s3->deleteObject('multiparttest');
+    }
 
-	public function testSeek() {
-		$data = file_get_contents(__FILE__);
+    public function testSeek()
+    {
+        $data = file_get_contents(__FILE__);
 
-		$instance = $this->getInstance();
-		$instance->writeObject('seek', $this->stringToStream($data));
+        $instance = $this->getInstance();
+        $instance->writeObject('seek', $this->stringToStream($data));
 
-		$read = $instance->readObject('seek');
-		$this->assertEquals(substr($data, 0, 100), fread($read, 100));
+        $read = $instance->readObject('seek');
+        $this->assertEquals(substr($data, 0, 100), fread($read, 100));
 
-		fseek($read, 10);
-		$this->assertEquals(substr($data, 10, 100), fread($read, 100));
+        fseek($read, 10);
+        $this->assertEquals(substr($data, 10, 100), fread($read, 100));
 
-		fseek($read, 100, SEEK_CUR);
-		$this->assertEquals(substr($data, 210, 100), fread($read, 100));
-	}
+        fseek($read, 100, SEEK_CUR);
+        $this->assertEquals(substr($data, 210, 100), fread($read, 100));
+
+        $instance->deleteObject('seek');
+    }
+
+    public function assertNoUpload($objectUrn)
+    {
+        $s3 = $this->getInstance();
+        $s3client = $s3->getConnection();
+        $uploads = $s3client->listMultipartUploads([
+            'Bucket' => $s3->getBucket(),
+            'Prefix' => $objectUrn,
+        ]);
+        //fwrite(STDERR, print_r($uploads, TRUE));
+        $this->assertArrayNotHasKey('Uploads', $uploads);
+    }
+
+    public function testEmptyUpload()
+    {
+        //$this->expectException(S3MultipartUploadException::class);
+        $s3 = $this->getInstance();
+
+        // create an empty stream and check that it fits to the
+        // pre-conditions in writeObject for the empty case
+        $emptyStream = fopen("php://memory", "r");
+        fwrite($emptyStream, null);
+
+        $s3->writeObject('emptystream', $emptyStream);
+
+        // this method intendedly produces an S3Exception
+        $this->assertNoUpload('emptystream');
+        $this->assertTrue($s3->objectExists('emptystream'));
+
+        $s3->deleteObject('emptystream');
+    }
 }