WebAPI/DeviceStorageAPI2

This is a very simple filesystem API based on the DeviceStorage API

API

FileSystem portion of the API:

partial interface Navigator {
  DeviceStorage getSandboxedFilesystem(DOMString filesystemName);
};

interface DeviceStorage {
  // Name will be generated by the implementation and returned as result of request
  DOMRequest add(Blob blob, DOMString name);

  // Returns the result as a File object
  DOMRequest get(DOMString name);

  // Returns the result as a FileHandle object which enables writing
  DOMRequest getEditable(DOMString name);

  // Deletes a file
  DOMRequest delete(DOMString name);
 
  // The .result property on each success call is set to a File object
  DeviceStorageCursor enumerate(optional DOMString directory)

  // The .result property on each success call is set to a FileHandle object
  DeviceStorageCursor enumeratEditable(optional DOMString directory)

  // The .result property on each success call is either a
  // { file: File } or { directory: "name" } object
  DeviceStorageCursor enumerateShallow(optional DOMString directory)

  // The .result property on each success call is either a
  // { file: FileHandle } or { directory: "name" } object
  DeviceStorageCursor enumerateShallowEditable(optional DOMString directory)
};

interface DeviceStorageCursor : DOMRequest {
 void continue();
};

The proposed API for FileHandle

interface FileHandle {
  LockedFile open([optional] DOMString mode); // defaults to "readonly"
  FileRequest getFile(); // .result is set to resulting File object
};

interface LockedFile {
  readonly attribute FileHandle fileHandle;
  readonly attribute DOMString mode;
  readonly attribute boolean active;

  attribute long long? location; // Set to null on call to append

  FileRequest readAsArrayBuffer(long size);
  FileRequest readAsText(long size, optional DOMString encoding);
  FileRequest write(DOMString or ArrayBuffer or ArrayBufferView or Blob value);
  FileRequest append(DOMString or ArrayBuffer or ArrayBufferView or Blob value);
  FileRequest truncate(optional long long size);
  FileRequest getMetadata(MetadataParams params);

  FileRequest flush(); // fsync

  void close(); // Prevents any further requests from being placed against this lock
  void abort(); // Immediately releases lock and stops any pending or running operations.
};

dictionary MetadataParameters {
  boolean size;
  boolean lastModified;
};

interface FileRequest : DOMRequest {
  readonly attribute LockedFile lockedFile;

  attribute EventHandler onprogress;
};

DOMRequest API (Same as IDBRequest, but with the IndexedDB-specific parts removed):

interface DOMRequest {
  readonly attribute DOMString readyState; // "pending" or "done"

  readonly attribute any result;
  readonly attribute DOMError error;

  attribute EventHandler onsuccess;
  attribute EventHandler onerror;
};