Rclone adds virtual directory entries to the directory cache when it
creates a file or directory.
Before this change these dropped out of the directory cache when the
directory cache was reloaded. This meant that when the directory cache
expired:
- On bucket based backends, empty directories would disappear
- When using VFS writeback, files in the process of uploading would disappear
This is fixed by keeping track of the virtual entries in each
directory. The virtual entries are removed when they become real - ie
the object is read back from the listing.
This also keeps tracks of deletes in the same way so if a file is
deleted, it will not re-appear when the directory cache is reloaded if
the deletion hasn't finished yet.
As part of this we take a copy of the directory path as calling
d.Path() violates the total locking order.
See the comment at the top of file.go for details
Before this change, change notify polls would clear the directory
cache recursively. So uploading a file to the root would clear the
entire directory cache.
After this change we just invalidate the directory cache of the parent
directory of the item and if the item was a directory we invalidate it
too.
Before this change when we renamed a directory this cleared the
directory cache for the parent directory too.
If the directory was remaining in the same parent this wasn't
necessary and caused the empty directory to fall out of the cache.
Fixes#3597
- Change rclone/fs interfaces to accept context.Context
- Update interface implementations to use context.Context
- Change top level usage to propagate context to lover level functions
Context propagation is needed for stopping transfers and passing other
request-scoped values.
Before this change we locked the root directory, recursively fetched
the listing, applied it then unlocked the root directory.
After this change we recursively fetch the listing then apply it with
the root directory locked which shortens the time that the root
directory is locked greatly.
With the original method and the new method the subdirectories are
left unlocked and so potentially could be changed leading to
inconsistencies. This change makes the potential for inconsistencies
slightly worse by leaving the root directory unlocked at a gain of a
much more responsive system while runing vfs/refresh.
See: https://forum.rclone.org/t/rclone-rc-vfs-refresh-locking-directory-being-refreshed/9004
Before this change when doing Mkdir the VFS layer could add the new
item to an unread directory which caused confusion.
It could also do mkdir on a file when run on a bucket based remote
which would temporarily overwrite the file with a directory.
Fixes#2993
Previously to this change, backends without the optional interface
DirMove could not rename directories.
This change uses the new operations.DirMove call to implement renaming
directories which will fall back to Move/Copy as necessary.
Reduce the number of nodes purged from the dir-cache when ForgetPath is
called. This is done by only forgetting the cache of the received path
and invalidating the parent folder cache by resetting *Dir.read.
The parent will read the listing on the next access and reuse the
dir-cache of entries in *Dir.items.
vfs/refresh will walk the directory tree for the given paths and
freshen the directory cache. It will use the fast-list capability
of the remote when enabled.
The purpose of this is to make it easier to maintain and eventually to
allow the rclone backends to be re-used in other projects without
having to use the rclone configuration system.
The new code layout is documented in CONTRIBUTING.
This adds new flags to mount, cmount, serve *
--cache-max-age duration Max age of objects in the cache. (default 1h0m0s)
--cache-mode string Cache mode off|minimal|writes|full (default "off")
--cache-poll-interval duration Interval to poll the cache for stale objects. (default 1m0s)
* Tests for VFS layer
* Small fixes found during testing
* Fix Close, Flush and Release behaviour for ReadFileHandle and WriteFileHandle
* Fix nil object bugs on File
