sangla1 / skydrive-fuse-fs

Script to mount Microsoft SkyDrive folder as a FUSE filesystem

skydrive-fuse-fs

Script to mount Microsoft SkyDrive folder as a FUSE filesystem.

This module is single-threaded and tries to do all operations as synchronously as possible - i.e. operations do not return until they're sequentially performed through the SkyDrive API, with the exception of metadata caches and any fuse/kernel caches.

That, lots of limitations, and the fact that API calls over https tend to be quite slow and frequent even with a keepalive connections, make it unsuitable for use as a general-purpose fs.

Main purpose of such abstraction is a convenient browsing (in shell or any general-purpose file manager), transfer or synchronization of files with simple unix tools like "ls", "cp" or "rsync".

Limitations

SkyDrive is not a filesystem (and in fact, basically a key-value storage), and doesn't expose anything resembling a posix fs interface, so lots of limitations apply.

By default (with "api_cache" option), module aggressively caches all retreived data to avoid time-consuming https requests, so any changes performed on SkyDrive outside of the script, might be invisible until remount or cache expiration / invalidation.

Even with api_cache disabled, lots of operations will still have a race conditions in them. For example, rename operation has to perform 4-6 API calls to check source and destination paths, whether it's a file/folder metadata update or a "move" operation, etc, and if something happens with remote paths between these checks, operation may fail with unpredictable results.

Rename operations are not atomic if destination path exists and is a file.

Write and truncate operations are performed by downloading the whole file, modifying it locally, uploading file back under temporary name, deleting the original file and renaming uploaded file to original name.

Not all potential API errors are translated into errno's (and probably not all of them can be mapped to these at all), and might manifest as EFAULT ("Bad Address") errors. Use "--debug" option to see which API calls might result in these - all fuse-requested operations and resulting API requests are logged there.

uid/gid/mode can potentially be stored in object metadata, but that is not implemented, and I don't see much point in it.

Usage

Requires python-skydrive module installed, use any of these lines:

pip install 'python-skydrive[conf]'   # system-wide by default, probably needs root
pip install --user 'python-skydrive[conf]'   # unprivileged install to ~/
easy_install python-skydrive PyYAML   # try to avoid that one

("python-skydrive[conf]" installs python-skydrive + PyYAML, latter being is a requirement for configuration-file handling in python-skydrive; install it in a similar way if you're using python setup.py install or some older packaging tools)

Before using this module, configuraton file with authentication data must be created, as described in python-skydrive documentation here.

Usage from checkout (no installation - apart from aforementioned module(s) - necessary), can be run from unprivileged user:

% ./skydrivefs /mnt/skydrive

Install to system-wide $PATH (might need system-wide fusepy module as well):

# pip install fusepy
# install -m755 skydrivefs /usr/local/sbin/

Use from $PATH with mount command:

# mount -t fuse.skydrivefs ~/.lcrc /mnt/skydrive

Examples with fstab(5) syntax (any one of these will do):

/var/lib/skydrive.yaml /mnt/skydrive fuse.skydrivefs defaults 0 0
/var/lib/skydrive.yaml:Pics /mnt/skydrive fuse.skydrivefs defaults 0 0

Available mount options can be found in skydrivefs --help output (skydrive-specific) and man mount.fuse (more general fuse options).

Latter example mounts "Pics" SkyDrive folder instead of root. "subdir" fuse module can be also used to the same effect.

Make sure configuration file (/var/lib/skydrive.yaml in fstab examples above) is not accessible to anyone but root (or dedicated user), and is writable - refreshed access tokens will be stored there.