nextcloud / server

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

Indentation +612 added lines, -612 removed lines

@@ -71,616 +71,616 @@
 use Sabre\DAV\IFile;
 
 class File extends Node implements IFile {
-	protected $request;
-
-	/**
-	 * Sets up the node, expects a full path name
-	 *
-	 * @param \OC\Files\View $view
-	 * @param \OCP\Files\FileInfo $info
-	 * @param \OCP\Share\IManager $shareManager
-	 * @param \OC\AppFramework\Http\Request $request
-	 */
-	public function __construct(View $view, FileInfo $info, IManager $shareManager = null, Request $request = null) {
-		parent::__construct($view, $info, $shareManager);
-
-		if (isset($request)) {
-			$this->request = $request;
-		} else {
-			$this->request = \OC::$server->getRequest();
-		}
-	}
-
-	/**
-	 * Updates the data
-	 *
-	 * The data argument is a readable stream resource.
-	 *
-	 * After a successful put operation, you may choose to return an ETag. The
-	 * etag must always be surrounded by double-quotes. These quotes must
-	 * appear in the actual string you're returning.
-	 *
-	 * Clients may use the ETag from a PUT request to later on make sure that
-	 * when they update the file, the contents haven't changed in the mean
-	 * time.
-	 *
-	 * If you don't plan to store the file byte-by-byte, and you return a
-	 * different object on a subsequent GET you are strongly recommended to not
-	 * return an ETag, and just return null.
-	 *
-	 * @param resource $data
-	 *
-	 * @throws Forbidden
-	 * @throws UnsupportedMediaType
-	 * @throws BadRequest
-	 * @throws Exception
-	 * @throws EntityTooLarge
-	 * @throws ServiceUnavailable
-	 * @throws FileLocked
-	 * @return string|null
-	 */
-	public function put($data) {
-		try {
-			$exists = $this->fileView->file_exists($this->path);
-			if ($this->info && $exists && !$this->info->isUpdateable()) {
-				throw new Forbidden();
-			}
-		} catch (StorageNotAvailableException $e) {
-			throw new ServiceUnavailable("File is not updatable: " . $e->getMessage());
-		}
-
-		// verify path of the target
-		$this->verifyPath();
-
-		// chunked handling
-		if (isset($_SERVER['HTTP_OC_CHUNKED'])) {
-			try {
-				return $this->createFileChunked($data);
-			} catch (\Exception $e) {
-				$this->convertToSabreException($e);
-			}
-		}
-
-		/** @var Storage $partStorage */
-		list($partStorage) = $this->fileView->resolvePath($this->path);
-		$needsPartFile = $partStorage->needsPartFile() && (strlen($this->path) > 1);
-
-		$view = \OC\Files\Filesystem::getView();
-
-		if ($needsPartFile) {
-			// mark file as partial while uploading (ignored by the scanner)
-			$partFilePath = $this->getPartFileBasePath($this->path) . '.ocTransferId' . rand() . '.part';
-
-			if (!$view->isCreatable($partFilePath) && $view->isUpdatable($this->path)) {
-				$needsPartFile = false;
-			}
-		}
-		if (!$needsPartFile) {
-			// upload file directly as the final path
-			$partFilePath = $this->path;
-
-			if ($view && !$this->emitPreHooks($exists)) {
-				throw new Exception('Could not write to final file, canceled by hook');
-			}
-		}
-
-		// the part file and target file might be on a different storage in case of a single file storage (e.g. single file share)
-		/** @var \OC\Files\Storage\Storage $partStorage */
-		list($partStorage, $internalPartPath) = $this->fileView->resolvePath($partFilePath);
-		/** @var \OC\Files\Storage\Storage $storage */
-		list($storage, $internalPath) = $this->fileView->resolvePath($this->path);
-		try {
-			if (!$needsPartFile) {
-				$this->changeLock(ILockingProvider::LOCK_EXCLUSIVE);
-			}
-
-			if (!is_resource($data)) {
-				$tmpData = fopen('php://temp', 'r+');
-				if ($data !== null) {
-					fwrite($tmpData, $data);
-					rewind($tmpData);
-				}
-				$data = $tmpData;
-			}
-
-			$data = HashWrapper::wrap($data, 'md5', function ($hash) {
-				$this->header('X-Hash-MD5: ' . $hash);
-			});
-			$data = HashWrapper::wrap($data, 'sha1', function ($hash) {
-				$this->header('X-Hash-SHA1: ' . $hash);
-			});
-			$data = HashWrapper::wrap($data, 'sha256', function ($hash) {
-				$this->header('X-Hash-SHA256: ' . $hash);
-			});
-
-			if ($partStorage->instanceOfStorage(Storage\IWriteStreamStorage::class)) {
-				$isEOF = false;
-				$wrappedData = CallbackWrapper::wrap($data, null, null, null, null, function ($stream) use (&$isEOF) {
-					$isEOF = feof($stream);
-				});
-
-				$count = $partStorage->writeStream($internalPartPath, $wrappedData);
-				$result = $count > 0;
-
-				if ($result === false) {
-					$result = $isEOF;
-					if (is_resource($wrappedData)) {
-						$result = feof($wrappedData);
-					}
-				}
-			} else {
-				$target = $partStorage->fopen($internalPartPath, 'wb');
-				if ($target === false) {
-					\OC::$server->getLogger()->error('\OC\Files\Filesystem::fopen() failed', ['app' => 'webdav']);
-					// because we have no clue about the cause we can only throw back a 500/Internal Server Error
-					throw new Exception('Could not write file contents');
-				}
-				list($count, $result) = \OC_Helper::streamCopy($data, $target);
-				fclose($target);
-			}
-
-			if ($result === false) {
-				$expected = -1;
-				if (isset($_SERVER['CONTENT_LENGTH'])) {
-					$expected = $_SERVER['CONTENT_LENGTH'];
-				}
-				if ($expected !== "0") {
-					throw new Exception('Error while copying file to target location (copied bytes: ' . $count . ', expected filesize: ' . $expected . ' )');
-				}
-			}
-
-			// if content length is sent by client:
-			// double check if the file was fully received
-			// compare expected and actual size
-			if (isset($_SERVER['CONTENT_LENGTH']) && $_SERVER['REQUEST_METHOD'] === 'PUT') {
-				$expected = (int)$_SERVER['CONTENT_LENGTH'];
-				if ($count !== $expected) {
-					throw new BadRequest('Expected filesize of ' . $expected . ' bytes but read (from Nextcloud client) and wrote (to Nextcloud storage) ' . $count . ' bytes. Could either be a network problem on the sending side or a problem writing to the storage on the server side.');
-				}
-			}
-		} catch (\Exception $e) {
-			$context = [];
-
-			if ($e instanceof LockedException) {
-				$context['level'] = ILogger::DEBUG;
-			}
-
-			\OC::$server->getLogger()->logException($e, $context);
-			if ($needsPartFile) {
-				$partStorage->unlink($internalPartPath);
-			}
-			$this->convertToSabreException($e);
-		}
-
-		try {
-			if ($needsPartFile) {
-				if ($view && !$this->emitPreHooks($exists)) {
-					$partStorage->unlink($internalPartPath);
-					throw new Exception('Could not rename part file to final file, canceled by hook');
-				}
-				try {
-					$this->changeLock(ILockingProvider::LOCK_EXCLUSIVE);
-				} catch (LockedException $e) {
-					// during very large uploads, the shared lock we got at the start might have been expired
-					// meaning that the above lock can fail not just only because somebody else got a shared lock
-					// or because there is no existing shared lock to make exclusive
-					//
-					// Thus we try to get a new exclusive lock, if the original lock failed because of a different shared
-					// lock this will still fail, if our original shared lock expired the new lock will be successful and
-					// the entire operation will be safe
-
-					try {
-						$this->acquireLock(ILockingProvider::LOCK_EXCLUSIVE);
-					} catch (LockedException $ex) {
-						if ($needsPartFile) {
-							$partStorage->unlink($internalPartPath);
-						}
-						throw new FileLocked($e->getMessage(), $e->getCode(), $e);
-					}
-				}
-
-				// rename to correct path
-				try {
-					$renameOkay = $storage->moveFromStorage($partStorage, $internalPartPath, $internalPath);
-					$fileExists = $storage->file_exists($internalPath);
-					if ($renameOkay === false || $fileExists === false) {
-						\OC::$server->getLogger()->error('renaming part file to final file failed $renameOkay: ' . ($renameOkay ? 'true' : 'false') . ', $fileExists: ' . ($fileExists ? 'true' : 'false') . ')', ['app' => 'webdav']);
-						throw new Exception('Could not rename part file to final file');
-					}
-				} catch (ForbiddenException $ex) {
-					if (!$ex->getRetry()) {
-						$partStorage->unlink($internalPartPath);
-					}
-					throw new DAVForbiddenException($ex->getMessage(), $ex->getRetry());
-				} catch (\Exception $e) {
-					$partStorage->unlink($internalPartPath);
-					$this->convertToSabreException($e);
-				}
-			}
-
-			// since we skipped the view we need to scan and emit the hooks ourselves
-			$storage->getUpdater()->update($internalPath);
-
-			try {
-				$this->changeLock(ILockingProvider::LOCK_SHARED);
-			} catch (LockedException $e) {
-				throw new FileLocked($e->getMessage(), $e->getCode(), $e);
-			}
-
-			// allow sync clients to send the mtime along in a header
-			if (isset($this->request->server['HTTP_X_OC_MTIME'])) {
-				$mtime = $this->sanitizeMtime($this->request->server['HTTP_X_OC_MTIME']);
-				if ($this->fileView->touch($this->path, $mtime)) {
-					$this->header('X-OC-MTime: accepted');
-				}
-			}
-
-			$fileInfoUpdate = [
-				'upload_time' => time()
-			];
-
-			// allow sync clients to send the creation time along in a header
-			if (isset($this->request->server['HTTP_X_OC_CTIME'])) {
-				$ctime = $this->sanitizeMtime($this->request->server['HTTP_X_OC_CTIME']);
-				$fileInfoUpdate['creation_time'] = $ctime;
-				$this->header('X-OC-CTime: accepted');
-			}
-
-			$this->fileView->putFileInfo($this->path, $fileInfoUpdate);
-
-			if ($view) {
-				$this->emitPostHooks($exists);
-			}
-
-			$this->refreshInfo();
-
-			if (isset($this->request->server['HTTP_OC_CHECKSUM'])) {
-				$checksum = trim($this->request->server['HTTP_OC_CHECKSUM']);
-				$this->fileView->putFileInfo($this->path, ['checksum' => $checksum]);
-				$this->refreshInfo();
-			} elseif ($this->getChecksum() !== null && $this->getChecksum() !== '') {
-				$this->fileView->putFileInfo($this->path, ['checksum' => '']);
-				$this->refreshInfo();
-			}
-		} catch (StorageNotAvailableException $e) {
-			throw new ServiceUnavailable("Failed to check file size: " . $e->getMessage(), 0, $e);
-		}
-
-		return '"' . $this->info->getEtag() . '"';
-	}
-
-	private function getPartFileBasePath($path) {
-		$partFileInStorage = \OC::$server->getConfig()->getSystemValue('part_file_in_storage', true);
-		if ($partFileInStorage) {
-			return $path;
-		} else {
-			return md5($path); // will place it in the root of the view with a unique name
-		}
-	}
-
-	/**
-	 * @param string $path
-	 */
-	private function emitPreHooks($exists, $path = null) {
-		if (is_null($path)) {
-			$path = $this->path;
-		}
-		$hookPath = Filesystem::getView()->getRelativePath($this->fileView->getAbsolutePath($path));
-		$run = true;
-
-		if (!$exists) {
-			\OC_Hook::emit(\OC\Files\Filesystem::CLASSNAME, \OC\Files\Filesystem::signal_create, [
-				\OC\Files\Filesystem::signal_param_path => $hookPath,
-				\OC\Files\Filesystem::signal_param_run => &$run,
-			]);
-		} else {
-			\OC_Hook::emit(\OC\Files\Filesystem::CLASSNAME, \OC\Files\Filesystem::signal_update, [
-				\OC\Files\Filesystem::signal_param_path => $hookPath,
-				\OC\Files\Filesystem::signal_param_run => &$run,
-			]);
-		}
-		\OC_Hook::emit(\OC\Files\Filesystem::CLASSNAME, \OC\Files\Filesystem::signal_write, [
-			\OC\Files\Filesystem::signal_param_path => $hookPath,
-			\OC\Files\Filesystem::signal_param_run => &$run,
-		]);
-		return $run;
-	}
-
-	/**
-	 * @param string $path
-	 */
-	private function emitPostHooks($exists, $path = null) {
-		if (is_null($path)) {
-			$path = $this->path;
-		}
-		$hookPath = Filesystem::getView()->getRelativePath($this->fileView->getAbsolutePath($path));
-		if (!$exists) {
-			\OC_Hook::emit(\OC\Files\Filesystem::CLASSNAME, \OC\Files\Filesystem::signal_post_create, [
-				\OC\Files\Filesystem::signal_param_path => $hookPath
-			]);
-		} else {
-			\OC_Hook::emit(\OC\Files\Filesystem::CLASSNAME, \OC\Files\Filesystem::signal_post_update, [
-				\OC\Files\Filesystem::signal_param_path => $hookPath
-			]);
-		}
-		\OC_Hook::emit(\OC\Files\Filesystem::CLASSNAME, \OC\Files\Filesystem::signal_post_write, [
-			\OC\Files\Filesystem::signal_param_path => $hookPath
-		]);
-	}
-
-	/**
-	 * Returns the data
-	 *
-	 * @return resource
-	 * @throws Forbidden
-	 * @throws ServiceUnavailable
-	 */
-	public function get() {
-		//throw exception if encryption is disabled but files are still encrypted
-		try {
-			if (!$this->info->isReadable()) {
-				// do a if the file did not exist
-				throw new NotFound();
-			}
-			try {
-				$res = $this->fileView->fopen(ltrim($this->path, '/'), 'rb');
-			} catch (\Exception $e) {
-				$this->convertToSabreException($e);
-			}
-			if ($res === false) {
-				throw new ServiceUnavailable("Could not open file");
-			}
-			return $res;
-		} catch (GenericEncryptionException $e) {
-			// returning 503 will allow retry of the operation at a later point in time
-			throw new ServiceUnavailable("Encryption not ready: " . $e->getMessage());
-		} catch (StorageNotAvailableException $e) {
-			throw new ServiceUnavailable("Failed to open file: " . $e->getMessage());
-		} catch (ForbiddenException $ex) {
-			throw new DAVForbiddenException($ex->getMessage(), $ex->getRetry());
-		} catch (LockedException $e) {
-			throw new FileLocked($e->getMessage(), $e->getCode(), $e);
-		}
-	}
-
-	/**
-	 * Delete the current file
-	 *
-	 * @throws Forbidden
-	 * @throws ServiceUnavailable
-	 */
-	public function delete() {
-		if (!$this->info->isDeletable()) {
-			throw new Forbidden();
-		}
-
-		try {
-			if (!$this->fileView->unlink($this->path)) {
-				// assume it wasn't possible to delete due to permissions
-				throw new Forbidden();
-			}
-		} catch (StorageNotAvailableException $e) {
-			throw new ServiceUnavailable("Failed to unlink: " . $e->getMessage());
-		} catch (ForbiddenException $ex) {
-			throw new DAVForbiddenException($ex->getMessage(), $ex->getRetry());
-		} catch (LockedException $e) {
-			throw new FileLocked($e->getMessage(), $e->getCode(), $e);
-		}
-	}
-
-	/**
-	 * Returns the mime-type for a file
-	 *
-	 * If null is returned, we'll assume application/octet-stream
-	 *
-	 * @return string
-	 */
-	public function getContentType() {
-		$mimeType = $this->info->getMimetype();
-
-		// PROPFIND needs to return the correct mime type, for consistency with the web UI
-		if (isset($_SERVER['REQUEST_METHOD']) && $_SERVER['REQUEST_METHOD'] === 'PROPFIND') {
-			return $mimeType;
-		}
-		return \OC::$server->getMimeTypeDetector()->getSecureMimeType($mimeType);
-	}
-
-	/**
-	 * @return array|false
-	 */
-	public function getDirectDownload() {
-		if (\OCP\App::isEnabled('encryption')) {
-			return [];
-		}
-		/** @var \OCP\Files\Storage $storage */
-		list($storage, $internalPath) = $this->fileView->resolvePath($this->path);
-		if (is_null($storage)) {
-			return [];
-		}
-
-		return $storage->getDirectDownload($internalPath);
-	}
-
-	/**
-	 * @param resource $data
-	 * @return null|string
-	 * @throws Exception
-	 * @throws BadRequest
-	 * @throws NotImplemented
-	 * @throws ServiceUnavailable
-	 */
-	private function createFileChunked($data) {
-		list($path, $name) = \Sabre\Uri\split($this->path);
-
-		$info = \OC_FileChunking::decodeName($name);
-		if (empty($info)) {
-			throw new NotImplemented('Invalid chunk name');
-		}
-
-		$chunk_handler = new \OC_FileChunking($info);
-		$bytesWritten = $chunk_handler->store($info['index'], $data);
-
-		//detect aborted upload
-		if (isset($_SERVER['REQUEST_METHOD']) && $_SERVER['REQUEST_METHOD'] === 'PUT') {
-			if (isset($_SERVER['CONTENT_LENGTH'])) {
-				$expected = (int)$_SERVER['CONTENT_LENGTH'];
-				if ($bytesWritten !== $expected) {
-					$chunk_handler->remove($info['index']);
-					throw new BadRequest('Expected filesize of ' . $expected . ' bytes but read (from Nextcloud client) and wrote (to Nextcloud storage) ' . $bytesWritten . ' bytes. Could either be a network problem on the sending side or a problem writing to the storage on the server side.');
-				}
-			}
-		}
-
-		if ($chunk_handler->isComplete()) {
-			/** @var Storage $storage */
-			list($storage,) = $this->fileView->resolvePath($path);
-			$needsPartFile = $storage->needsPartFile();
-			$partFile = null;
-
-			$targetPath = $path . '/' . $info['name'];
-			/** @var \OC\Files\Storage\Storage $targetStorage */
-			list($targetStorage, $targetInternalPath) = $this->fileView->resolvePath($targetPath);
-
-			$exists = $this->fileView->file_exists($targetPath);
-
-			try {
-				$this->fileView->lockFile($targetPath, ILockingProvider::LOCK_SHARED);
-
-				$this->emitPreHooks($exists, $targetPath);
-				$this->fileView->changeLock($targetPath, ILockingProvider::LOCK_EXCLUSIVE);
-				/** @var \OC\Files\Storage\Storage $targetStorage */
-				list($targetStorage, $targetInternalPath) = $this->fileView->resolvePath($targetPath);
-
-				if ($needsPartFile) {
-					// we first assembly the target file as a part file
-					$partFile = $this->getPartFileBasePath($path . '/' . $info['name']) . '.ocTransferId' . $info['transferid'] . '.part';
-					/** @var \OC\Files\Storage\Storage $targetStorage */
-					list($partStorage, $partInternalPath) = $this->fileView->resolvePath($partFile);
-
-
-					$chunk_handler->file_assemble($partStorage, $partInternalPath);
-
-					// here is the final atomic rename
-					$renameOkay = $targetStorage->moveFromStorage($partStorage, $partInternalPath, $targetInternalPath);
-					$fileExists = $targetStorage->file_exists($targetInternalPath);
-					if ($renameOkay === false || $fileExists === false) {
-						\OC::$server->getLogger()->error('\OC\Files\Filesystem::rename() failed', ['app' => 'webdav']);
-						// only delete if an error occurred and the target file was already created
-						if ($fileExists) {
-							// set to null to avoid double-deletion when handling exception
-							// stray part file
-							$partFile = null;
-							$targetStorage->unlink($targetInternalPath);
-						}
-						$this->fileView->changeLock($targetPath, ILockingProvider::LOCK_SHARED);
-						throw new Exception('Could not rename part file assembled from chunks');
-					}
-				} else {
-					// assemble directly into the final file
-					$chunk_handler->file_assemble($targetStorage, $targetInternalPath);
-				}
-
-				// allow sync clients to send the mtime along in a header
-				if (isset($this->request->server['HTTP_X_OC_MTIME'])) {
-					$mtime = $this->sanitizeMtime($this->request->server['HTTP_X_OC_MTIME']);
-					if ($targetStorage->touch($targetInternalPath, $mtime)) {
-						$this->header('X-OC-MTime: accepted');
-					}
-				}
-
-				// since we skipped the view we need to scan and emit the hooks ourselves
-				$targetStorage->getUpdater()->update($targetInternalPath);
-
-				$this->fileView->changeLock($targetPath, ILockingProvider::LOCK_SHARED);
-
-				$this->emitPostHooks($exists, $targetPath);
-
-				// FIXME: should call refreshInfo but can't because $this->path is not the of the final file
-				$info = $this->fileView->getFileInfo($targetPath);
-
-				if (isset($this->request->server['HTTP_OC_CHECKSUM'])) {
-					$checksum = trim($this->request->server['HTTP_OC_CHECKSUM']);
-					$this->fileView->putFileInfo($targetPath, ['checksum' => $checksum]);
-				} elseif ($info->getChecksum() !== null && $info->getChecksum() !== '') {
-					$this->fileView->putFileInfo($this->path, ['checksum' => '']);
-				}
-
-				$this->fileView->unlockFile($targetPath, ILockingProvider::LOCK_SHARED);
-
-				return $info->getEtag();
-			} catch (\Exception $e) {
-				if ($partFile !== null) {
-					$targetStorage->unlink($targetInternalPath);
-				}
-				$this->convertToSabreException($e);
-			}
-		}
-
-		return null;
-	}
-
-	/**
-	 * Convert the given exception to a SabreException instance
-	 *
-	 * @param \Exception $e
-	 *
-	 * @throws \Sabre\DAV\Exception
-	 */
-	private function convertToSabreException(\Exception $e) {
-		if ($e instanceof \Sabre\DAV\Exception) {
-			throw $e;
-		}
-		if ($e instanceof NotPermittedException) {
-			// a more general case - due to whatever reason the content could not be written
-			throw new Forbidden($e->getMessage(), 0, $e);
-		}
-		if ($e instanceof ForbiddenException) {
-			// the path for the file was forbidden
-			throw new DAVForbiddenException($e->getMessage(), $e->getRetry(), $e);
-		}
-		if ($e instanceof EntityTooLargeException) {
-			// the file is too big to be stored
-			throw new EntityTooLarge($e->getMessage(), 0, $e);
-		}
-		if ($e instanceof InvalidContentException) {
-			// the file content is not permitted
-			throw new UnsupportedMediaType($e->getMessage(), 0, $e);
-		}
-		if ($e instanceof InvalidPathException) {
-			// the path for the file was not valid
-			// TODO: find proper http status code for this case
-			throw new Forbidden($e->getMessage(), 0, $e);
-		}
-		if ($e instanceof LockedException || $e instanceof LockNotAcquiredException) {
-			// the file is currently being written to by another process
-			throw new FileLocked($e->getMessage(), $e->getCode(), $e);
-		}
-		if ($e instanceof GenericEncryptionException) {
-			// returning 503 will allow retry of the operation at a later point in time
-			throw new ServiceUnavailable('Encryption not ready: ' . $e->getMessage(), 0, $e);
-		}
-		if ($e instanceof StorageNotAvailableException) {
-			throw new ServiceUnavailable('Failed to write file contents: ' . $e->getMessage(), 0, $e);
-		}
-		if ($e instanceof NotFoundException) {
-			throw new NotFound('File not found: ' . $e->getMessage(), 0, $e);
-		}
-
-		throw new \Sabre\DAV\Exception($e->getMessage(), 0, $e);
-	}
-
-	/**
-	 * Get the checksum for this file
-	 *
-	 * @return string
-	 */
-	public function getChecksum() {
-		return $this->info->getChecksum();
-	}
-
-	protected function header($string) {
-		if (!\OC::$CLI) {
-			\header($string);
-		}
-	}
+    protected $request;
+
+    /**
+     * Sets up the node, expects a full path name
+     *
+     * @param \OC\Files\View $view
+     * @param \OCP\Files\FileInfo $info
+     * @param \OCP\Share\IManager $shareManager
+     * @param \OC\AppFramework\Http\Request $request
+     */
+    public function __construct(View $view, FileInfo $info, IManager $shareManager = null, Request $request = null) {
+        parent::__construct($view, $info, $shareManager);
+
+        if (isset($request)) {
+            $this->request = $request;
+        } else {
+            $this->request = \OC::$server->getRequest();
+        }
+    }
+
+    /**
+     * Updates the data
+     *
+     * The data argument is a readable stream resource.
+     *
+     * After a successful put operation, you may choose to return an ETag. The
+     * etag must always be surrounded by double-quotes. These quotes must
+     * appear in the actual string you're returning.
+     *
+     * Clients may use the ETag from a PUT request to later on make sure that
+     * when they update the file, the contents haven't changed in the mean
+     * time.
+     *
+     * If you don't plan to store the file byte-by-byte, and you return a
+     * different object on a subsequent GET you are strongly recommended to not
+     * return an ETag, and just return null.
+     *
+     * @param resource $data
+     *
+     * @throws Forbidden
+     * @throws UnsupportedMediaType
+     * @throws BadRequest
+     * @throws Exception
+     * @throws EntityTooLarge
+     * @throws ServiceUnavailable
+     * @throws FileLocked
+     * @return string|null
+     */
+    public function put($data) {
+        try {
+            $exists = $this->fileView->file_exists($this->path);
+            if ($this->info && $exists && !$this->info->isUpdateable()) {
+                throw new Forbidden();
+            }
+        } catch (StorageNotAvailableException $e) {
+            throw new ServiceUnavailable("File is not updatable: " . $e->getMessage());
+        }
+
+        // verify path of the target
+        $this->verifyPath();
+
+        // chunked handling
+        if (isset($_SERVER['HTTP_OC_CHUNKED'])) {
+            try {
+                return $this->createFileChunked($data);
+            } catch (\Exception $e) {
+                $this->convertToSabreException($e);
+            }
+        }
+
+        /** @var Storage $partStorage */
+        list($partStorage) = $this->fileView->resolvePath($this->path);
+        $needsPartFile = $partStorage->needsPartFile() && (strlen($this->path) > 1);
+
+        $view = \OC\Files\Filesystem::getView();
+
+        if ($needsPartFile) {
+            // mark file as partial while uploading (ignored by the scanner)
+            $partFilePath = $this->getPartFileBasePath($this->path) . '.ocTransferId' . rand() . '.part';
+
+            if (!$view->isCreatable($partFilePath) && $view->isUpdatable($this->path)) {
+                $needsPartFile = false;
+            }
+        }
+        if (!$needsPartFile) {
+            // upload file directly as the final path
+            $partFilePath = $this->path;
+
+            if ($view && !$this->emitPreHooks($exists)) {
+                throw new Exception('Could not write to final file, canceled by hook');
+            }
+        }
+
+        // the part file and target file might be on a different storage in case of a single file storage (e.g. single file share)
+        /** @var \OC\Files\Storage\Storage $partStorage */
+        list($partStorage, $internalPartPath) = $this->fileView->resolvePath($partFilePath);
+        /** @var \OC\Files\Storage\Storage $storage */
+        list($storage, $internalPath) = $this->fileView->resolvePath($this->path);
+        try {
+            if (!$needsPartFile) {
+                $this->changeLock(ILockingProvider::LOCK_EXCLUSIVE);
+            }
+
+            if (!is_resource($data)) {
+                $tmpData = fopen('php://temp', 'r+');
+                if ($data !== null) {
+                    fwrite($tmpData, $data);
+                    rewind($tmpData);
+                }
+                $data = $tmpData;
+            }
+
+            $data = HashWrapper::wrap($data, 'md5', function ($hash) {
+                $this->header('X-Hash-MD5: ' . $hash);
+            });
+            $data = HashWrapper::wrap($data, 'sha1', function ($hash) {
+                $this->header('X-Hash-SHA1: ' . $hash);
+            });
+            $data = HashWrapper::wrap($data, 'sha256', function ($hash) {
+                $this->header('X-Hash-SHA256: ' . $hash);
+            });
+
+            if ($partStorage->instanceOfStorage(Storage\IWriteStreamStorage::class)) {
+                $isEOF = false;
+                $wrappedData = CallbackWrapper::wrap($data, null, null, null, null, function ($stream) use (&$isEOF) {
+                    $isEOF = feof($stream);
+                });
+
+                $count = $partStorage->writeStream($internalPartPath, $wrappedData);
+                $result = $count > 0;
+
+                if ($result === false) {
+                    $result = $isEOF;
+                    if (is_resource($wrappedData)) {
+                        $result = feof($wrappedData);
+                    }
+                }
+            } else {
+                $target = $partStorage->fopen($internalPartPath, 'wb');
+                if ($target === false) {
+                    \OC::$server->getLogger()->error('\OC\Files\Filesystem::fopen() failed', ['app' => 'webdav']);
+                    // because we have no clue about the cause we can only throw back a 500/Internal Server Error
+                    throw new Exception('Could not write file contents');
+                }
+                list($count, $result) = \OC_Helper::streamCopy($data, $target);
+                fclose($target);
+            }
+
+            if ($result === false) {
+                $expected = -1;
+                if (isset($_SERVER['CONTENT_LENGTH'])) {
+                    $expected = $_SERVER['CONTENT_LENGTH'];
+                }
+                if ($expected !== "0") {
+                    throw new Exception('Error while copying file to target location (copied bytes: ' . $count . ', expected filesize: ' . $expected . ' )');
+                }
+            }
+
+            // if content length is sent by client:
+            // double check if the file was fully received
+            // compare expected and actual size
+            if (isset($_SERVER['CONTENT_LENGTH']) && $_SERVER['REQUEST_METHOD'] === 'PUT') {
+                $expected = (int)$_SERVER['CONTENT_LENGTH'];
+                if ($count !== $expected) {
+                    throw new BadRequest('Expected filesize of ' . $expected . ' bytes but read (from Nextcloud client) and wrote (to Nextcloud storage) ' . $count . ' bytes. Could either be a network problem on the sending side or a problem writing to the storage on the server side.');
+                }
+            }
+        } catch (\Exception $e) {
+            $context = [];
+
+            if ($e instanceof LockedException) {
+                $context['level'] = ILogger::DEBUG;
+            }
+
+            \OC::$server->getLogger()->logException($e, $context);
+            if ($needsPartFile) {
+                $partStorage->unlink($internalPartPath);
+            }
+            $this->convertToSabreException($e);
+        }
+
+        try {
+            if ($needsPartFile) {
+                if ($view && !$this->emitPreHooks($exists)) {
+                    $partStorage->unlink($internalPartPath);
+                    throw new Exception('Could not rename part file to final file, canceled by hook');
+                }
+                try {
+                    $this->changeLock(ILockingProvider::LOCK_EXCLUSIVE);
+                } catch (LockedException $e) {
+                    // during very large uploads, the shared lock we got at the start might have been expired
+                    // meaning that the above lock can fail not just only because somebody else got a shared lock
+                    // or because there is no existing shared lock to make exclusive
+                    //
+                    // Thus we try to get a new exclusive lock, if the original lock failed because of a different shared
+                    // lock this will still fail, if our original shared lock expired the new lock will be successful and
+                    // the entire operation will be safe
+
+                    try {
+                        $this->acquireLock(ILockingProvider::LOCK_EXCLUSIVE);
+                    } catch (LockedException $ex) {
+                        if ($needsPartFile) {
+                            $partStorage->unlink($internalPartPath);
+                        }
+                        throw new FileLocked($e->getMessage(), $e->getCode(), $e);
+                    }
+                }
+
+                // rename to correct path
+                try {
+                    $renameOkay = $storage->moveFromStorage($partStorage, $internalPartPath, $internalPath);
+                    $fileExists = $storage->file_exists($internalPath);
+                    if ($renameOkay === false || $fileExists === false) {
+                        \OC::$server->getLogger()->error('renaming part file to final file failed $renameOkay: ' . ($renameOkay ? 'true' : 'false') . ', $fileExists: ' . ($fileExists ? 'true' : 'false') . ')', ['app' => 'webdav']);
+                        throw new Exception('Could not rename part file to final file');
+                    }
+                } catch (ForbiddenException $ex) {
+                    if (!$ex->getRetry()) {
+                        $partStorage->unlink($internalPartPath);
+                    }
+                    throw new DAVForbiddenException($ex->getMessage(), $ex->getRetry());
+                } catch (\Exception $e) {
+                    $partStorage->unlink($internalPartPath);
+                    $this->convertToSabreException($e);
+                }
+            }
+
+            // since we skipped the view we need to scan and emit the hooks ourselves
+            $storage->getUpdater()->update($internalPath);
+
+            try {
+                $this->changeLock(ILockingProvider::LOCK_SHARED);
+            } catch (LockedException $e) {
+                throw new FileLocked($e->getMessage(), $e->getCode(), $e);
+            }
+
+            // allow sync clients to send the mtime along in a header
+            if (isset($this->request->server['HTTP_X_OC_MTIME'])) {
+                $mtime = $this->sanitizeMtime($this->request->server['HTTP_X_OC_MTIME']);
+                if ($this->fileView->touch($this->path, $mtime)) {
+                    $this->header('X-OC-MTime: accepted');
+                }
+            }
+
+            $fileInfoUpdate = [
+                'upload_time' => time()
+            ];
+
+            // allow sync clients to send the creation time along in a header
+            if (isset($this->request->server['HTTP_X_OC_CTIME'])) {
+                $ctime = $this->sanitizeMtime($this->request->server['HTTP_X_OC_CTIME']);
+                $fileInfoUpdate['creation_time'] = $ctime;
+                $this->header('X-OC-CTime: accepted');
+            }
+
+            $this->fileView->putFileInfo($this->path, $fileInfoUpdate);
+
+            if ($view) {
+                $this->emitPostHooks($exists);
+            }
+
+            $this->refreshInfo();
+
+            if (isset($this->request->server['HTTP_OC_CHECKSUM'])) {
+                $checksum = trim($this->request->server['HTTP_OC_CHECKSUM']);
+                $this->fileView->putFileInfo($this->path, ['checksum' => $checksum]);
+                $this->refreshInfo();
+            } elseif ($this->getChecksum() !== null && $this->getChecksum() !== '') {
+                $this->fileView->putFileInfo($this->path, ['checksum' => '']);
+                $this->refreshInfo();
+            }
+        } catch (StorageNotAvailableException $e) {
+            throw new ServiceUnavailable("Failed to check file size: " . $e->getMessage(), 0, $e);
+        }
+
+        return '"' . $this->info->getEtag() . '"';
+    }
+
+    private function getPartFileBasePath($path) {
+        $partFileInStorage = \OC::$server->getConfig()->getSystemValue('part_file_in_storage', true);
+        if ($partFileInStorage) {
+            return $path;
+        } else {
+            return md5($path); // will place it in the root of the view with a unique name
+        }
+    }
+
+    /**
+     * @param string $path
+     */
+    private function emitPreHooks($exists, $path = null) {
+        if (is_null($path)) {
+            $path = $this->path;
+        }
+        $hookPath = Filesystem::getView()->getRelativePath($this->fileView->getAbsolutePath($path));
+        $run = true;
+
+        if (!$exists) {
+            \OC_Hook::emit(\OC\Files\Filesystem::CLASSNAME, \OC\Files\Filesystem::signal_create, [
+                \OC\Files\Filesystem::signal_param_path => $hookPath,
+                \OC\Files\Filesystem::signal_param_run => &$run,
+            ]);
+        } else {
+            \OC_Hook::emit(\OC\Files\Filesystem::CLASSNAME, \OC\Files\Filesystem::signal_update, [
+                \OC\Files\Filesystem::signal_param_path => $hookPath,
+                \OC\Files\Filesystem::signal_param_run => &$run,
+            ]);
+        }
+        \OC_Hook::emit(\OC\Files\Filesystem::CLASSNAME, \OC\Files\Filesystem::signal_write, [
+            \OC\Files\Filesystem::signal_param_path => $hookPath,
+            \OC\Files\Filesystem::signal_param_run => &$run,
+        ]);
+        return $run;
+    }
+
+    /**
+     * @param string $path
+     */
+    private function emitPostHooks($exists, $path = null) {
+        if (is_null($path)) {
+            $path = $this->path;
+        }
+        $hookPath = Filesystem::getView()->getRelativePath($this->fileView->getAbsolutePath($path));
+        if (!$exists) {
+            \OC_Hook::emit(\OC\Files\Filesystem::CLASSNAME, \OC\Files\Filesystem::signal_post_create, [
+                \OC\Files\Filesystem::signal_param_path => $hookPath
+            ]);
+        } else {
+            \OC_Hook::emit(\OC\Files\Filesystem::CLASSNAME, \OC\Files\Filesystem::signal_post_update, [
+                \OC\Files\Filesystem::signal_param_path => $hookPath
+            ]);
+        }
+        \OC_Hook::emit(\OC\Files\Filesystem::CLASSNAME, \OC\Files\Filesystem::signal_post_write, [
+            \OC\Files\Filesystem::signal_param_path => $hookPath
+        ]);
+    }
+
+    /**
+     * Returns the data
+     *
+     * @return resource
+     * @throws Forbidden
+     * @throws ServiceUnavailable
+     */
+    public function get() {
+        //throw exception if encryption is disabled but files are still encrypted
+        try {
+            if (!$this->info->isReadable()) {
+                // do a if the file did not exist
+                throw new NotFound();
+            }
+            try {
+                $res = $this->fileView->fopen(ltrim($this->path, '/'), 'rb');
+            } catch (\Exception $e) {
+                $this->convertToSabreException($e);
+            }
+            if ($res === false) {
+                throw new ServiceUnavailable("Could not open file");
+            }
+            return $res;
+        } catch (GenericEncryptionException $e) {
+            // returning 503 will allow retry of the operation at a later point in time
+            throw new ServiceUnavailable("Encryption not ready: " . $e->getMessage());
+        } catch (StorageNotAvailableException $e) {
+            throw new ServiceUnavailable("Failed to open file: " . $e->getMessage());
+        } catch (ForbiddenException $ex) {
+            throw new DAVForbiddenException($ex->getMessage(), $ex->getRetry());
+        } catch (LockedException $e) {
+            throw new FileLocked($e->getMessage(), $e->getCode(), $e);
+        }
+    }
+
+    /**
+     * Delete the current file
+     *
+     * @throws Forbidden
+     * @throws ServiceUnavailable
+     */
+    public function delete() {
+        if (!$this->info->isDeletable()) {
+            throw new Forbidden();
+        }
+
+        try {
+            if (!$this->fileView->unlink($this->path)) {
+                // assume it wasn't possible to delete due to permissions
+                throw new Forbidden();
+            }
+        } catch (StorageNotAvailableException $e) {
+            throw new ServiceUnavailable("Failed to unlink: " . $e->getMessage());
+        } catch (ForbiddenException $ex) {
+            throw new DAVForbiddenException($ex->getMessage(), $ex->getRetry());
+        } catch (LockedException $e) {
+            throw new FileLocked($e->getMessage(), $e->getCode(), $e);
+        }
+    }
+
+    /**
+     * Returns the mime-type for a file
+     *
+     * If null is returned, we'll assume application/octet-stream
+     *
+     * @return string
+     */
+    public function getContentType() {
+        $mimeType = $this->info->getMimetype();
+
+        // PROPFIND needs to return the correct mime type, for consistency with the web UI
+        if (isset($_SERVER['REQUEST_METHOD']) && $_SERVER['REQUEST_METHOD'] === 'PROPFIND') {
+            return $mimeType;
+        }
+        return \OC::$server->getMimeTypeDetector()->getSecureMimeType($mimeType);
+    }
+
+    /**
+     * @return array|false
+     */
+    public function getDirectDownload() {
+        if (\OCP\App::isEnabled('encryption')) {
+            return [];
+        }
+        /** @var \OCP\Files\Storage $storage */
+        list($storage, $internalPath) = $this->fileView->resolvePath($this->path);
+        if (is_null($storage)) {
+            return [];
+        }
+
+        return $storage->getDirectDownload($internalPath);
+    }
+
+    /**
+     * @param resource $data
+     * @return null|string
+     * @throws Exception
+     * @throws BadRequest
+     * @throws NotImplemented
+     * @throws ServiceUnavailable
+     */
+    private function createFileChunked($data) {
+        list($path, $name) = \Sabre\Uri\split($this->path);
+
+        $info = \OC_FileChunking::decodeName($name);
+        if (empty($info)) {
+            throw new NotImplemented('Invalid chunk name');
+        }
+
+        $chunk_handler = new \OC_FileChunking($info);
+        $bytesWritten = $chunk_handler->store($info['index'], $data);
+
+        //detect aborted upload
+        if (isset($_SERVER['REQUEST_METHOD']) && $_SERVER['REQUEST_METHOD'] === 'PUT') {
+            if (isset($_SERVER['CONTENT_LENGTH'])) {
+                $expected = (int)$_SERVER['CONTENT_LENGTH'];
+                if ($bytesWritten !== $expected) {
+                    $chunk_handler->remove($info['index']);
+                    throw new BadRequest('Expected filesize of ' . $expected . ' bytes but read (from Nextcloud client) and wrote (to Nextcloud storage) ' . $bytesWritten . ' bytes. Could either be a network problem on the sending side or a problem writing to the storage on the server side.');
+                }
+            }
+        }
+
+        if ($chunk_handler->isComplete()) {
+            /** @var Storage $storage */
+            list($storage,) = $this->fileView->resolvePath($path);
+            $needsPartFile = $storage->needsPartFile();
+            $partFile = null;
+
+            $targetPath = $path . '/' . $info['name'];
+            /** @var \OC\Files\Storage\Storage $targetStorage */
+            list($targetStorage, $targetInternalPath) = $this->fileView->resolvePath($targetPath);
+
+            $exists = $this->fileView->file_exists($targetPath);
+
+            try {
+                $this->fileView->lockFile($targetPath, ILockingProvider::LOCK_SHARED);
+
+                $this->emitPreHooks($exists, $targetPath);
+                $this->fileView->changeLock($targetPath, ILockingProvider::LOCK_EXCLUSIVE);
+                /** @var \OC\Files\Storage\Storage $targetStorage */
+                list($targetStorage, $targetInternalPath) = $this->fileView->resolvePath($targetPath);
+
+                if ($needsPartFile) {
+                    // we first assembly the target file as a part file
+                    $partFile = $this->getPartFileBasePath($path . '/' . $info['name']) . '.ocTransferId' . $info['transferid'] . '.part';
+                    /** @var \OC\Files\Storage\Storage $targetStorage */
+                    list($partStorage, $partInternalPath) = $this->fileView->resolvePath($partFile);
+
+
+                    $chunk_handler->file_assemble($partStorage, $partInternalPath);
+
+                    // here is the final atomic rename
+                    $renameOkay = $targetStorage->moveFromStorage($partStorage, $partInternalPath, $targetInternalPath);
+                    $fileExists = $targetStorage->file_exists($targetInternalPath);
+                    if ($renameOkay === false || $fileExists === false) {
+                        \OC::$server->getLogger()->error('\OC\Files\Filesystem::rename() failed', ['app' => 'webdav']);
+                        // only delete if an error occurred and the target file was already created
+                        if ($fileExists) {
+                            // set to null to avoid double-deletion when handling exception
+                            // stray part file
+                            $partFile = null;
+                            $targetStorage->unlink($targetInternalPath);
+                        }
+                        $this->fileView->changeLock($targetPath, ILockingProvider::LOCK_SHARED);
+                        throw new Exception('Could not rename part file assembled from chunks');
+                    }
+                } else {
+                    // assemble directly into the final file
+                    $chunk_handler->file_assemble($targetStorage, $targetInternalPath);
+                }
+
+                // allow sync clients to send the mtime along in a header
+                if (isset($this->request->server['HTTP_X_OC_MTIME'])) {
+                    $mtime = $this->sanitizeMtime($this->request->server['HTTP_X_OC_MTIME']);
+                    if ($targetStorage->touch($targetInternalPath, $mtime)) {
+                        $this->header('X-OC-MTime: accepted');
+                    }
+                }
+
+                // since we skipped the view we need to scan and emit the hooks ourselves
+                $targetStorage->getUpdater()->update($targetInternalPath);
+
+                $this->fileView->changeLock($targetPath, ILockingProvider::LOCK_SHARED);
+
+                $this->emitPostHooks($exists, $targetPath);
+
+                // FIXME: should call refreshInfo but can't because $this->path is not the of the final file
+                $info = $this->fileView->getFileInfo($targetPath);
+
+                if (isset($this->request->server['HTTP_OC_CHECKSUM'])) {
+                    $checksum = trim($this->request->server['HTTP_OC_CHECKSUM']);
+                    $this->fileView->putFileInfo($targetPath, ['checksum' => $checksum]);
+                } elseif ($info->getChecksum() !== null && $info->getChecksum() !== '') {
+                    $this->fileView->putFileInfo($this->path, ['checksum' => '']);
+                }
+
+                $this->fileView->unlockFile($targetPath, ILockingProvider::LOCK_SHARED);
+
+                return $info->getEtag();
+            } catch (\Exception $e) {
+                if ($partFile !== null) {
+                    $targetStorage->unlink($targetInternalPath);
+                }
+                $this->convertToSabreException($e);
+            }
+        }
+
+        return null;
+    }
+
+    /**
+     * Convert the given exception to a SabreException instance
+     *
+     * @param \Exception $e
+     *
+     * @throws \Sabre\DAV\Exception
+     */
+    private function convertToSabreException(\Exception $e) {
+        if ($e instanceof \Sabre\DAV\Exception) {
+            throw $e;
+        }
+        if ($e instanceof NotPermittedException) {
+            // a more general case - due to whatever reason the content could not be written
+            throw new Forbidden($e->getMessage(), 0, $e);
+        }
+        if ($e instanceof ForbiddenException) {
+            // the path for the file was forbidden
+            throw new DAVForbiddenException($e->getMessage(), $e->getRetry(), $e);
+        }
+        if ($e instanceof EntityTooLargeException) {
+            // the file is too big to be stored
+            throw new EntityTooLarge($e->getMessage(), 0, $e);
+        }
+        if ($e instanceof InvalidContentException) {
+            // the file content is not permitted
+            throw new UnsupportedMediaType($e->getMessage(), 0, $e);
+        }
+        if ($e instanceof InvalidPathException) {
+            // the path for the file was not valid
+            // TODO: find proper http status code for this case
+            throw new Forbidden($e->getMessage(), 0, $e);
+        }
+        if ($e instanceof LockedException || $e instanceof LockNotAcquiredException) {
+            // the file is currently being written to by another process
+            throw new FileLocked($e->getMessage(), $e->getCode(), $e);
+        }
+        if ($e instanceof GenericEncryptionException) {
+            // returning 503 will allow retry of the operation at a later point in time
+            throw new ServiceUnavailable('Encryption not ready: ' . $e->getMessage(), 0, $e);
+        }
+        if ($e instanceof StorageNotAvailableException) {
+            throw new ServiceUnavailable('Failed to write file contents: ' . $e->getMessage(), 0, $e);
+        }
+        if ($e instanceof NotFoundException) {
+            throw new NotFound('File not found: ' . $e->getMessage(), 0, $e);
+        }
+
+        throw new \Sabre\DAV\Exception($e->getMessage(), 0, $e);
+    }
+
+    /**
+     * Get the checksum for this file
+     *
+     * @return string
+     */
+    public function getChecksum() {
+        return $this->info->getChecksum();
+    }
+
+    protected function header($string) {
+        if (!\OC::$CLI) {
+            \header($string);
+        }
+    }
 }