The idea is that the user's question is "is this folder's data available
offline?" and not "does this folder have AlwaysLocal pin state?".
The the answers to the two questions can differ: an always-local
folder can have subitems that are not always-local and are dehydrated.
The new availability enum intends to describe the answer to the user's
actual question and can be derived from pin states. If pin states aren't
stored in the database the way of calculating availability will depend
on the vfs plugin.
The pin state is a per-item attribute that has an effect on _type:
AlwaysLocal dehydrated files will be marked for hydration and OnlineOnly
hydrated files will be marked for dehydration.
Where exactly this effect materializes depends on how the pin states are
stored. If they're stored in the db (suffix) the dbEntry._type is
changed during the discovery.
If the pin state is stored in the filesystem, the localEntry._type must
be adjusted by the plugin's stat callback.
This patch makes pin states behave more consistently between plugins.
Previously with suffix-vfs pin states only had an effect on new remote
files. Now the effect of pinning or unpinning files or directories is as
documented and similar to other plugins.
Previously removing the vfs suffix of a file always triggered a
conflict. Now it may just cause a file download.
This was done because users expected symmetry in the rename actions and
renaming foo -> foo.owncloud already triggers the "make the file
virtual" action. Now foo.owncloud -> foo triggers the "download the
contents" action.
Users can rename a file *and* add/remove the vfs suffix at the same time
leading to very complex sync actions. This patch doesn't add support for
them, but adds tests and makes sure these cases do not cause unintened
behavior.
The rename will be propagated, but the users's hydrate/dehydrate request
will be ignored.
As far as I'm aware local discovery can be skipped on folders that are
selective-sync blacklisted, so a local discovery is required when an
entry is removed from the blacklist.
Also rename
avoidReadFromDbOnNextSync() -> schedulePathForRemoteDiscovery()
since the old name might also imply it's not read from db in the local
discovery - which is not the case. Use Folder::
schedulePathForLocalDiscovery() for that.
Creating a new virtual file and replacing a file with a virtual one now
have their own text in the protocol, not just "Downloaded".
To do this, the SyncFileItem type is kept as
ItemTypeVirtualFileDehydration for these actions. Added new code to
ensure the type isn't written to the database.
While looking at this, I've also added documentation on SyncFileItem's
_file, _renameTarget, _originalFile and destination() because some of
the semantics weren't clear.
That change will be useful for the notifications. Previously the
dehydrated files were reported as "newly downloaded", now they're
reported as "updated".
- SyncJournalDB functions now behind internalPinStates() to avoid
accidental usage, when nearly everyone should go through Vfs.
- Rename Vfs::getPinState() to Vfs::pinState()
This helps support 2.5 settings where there are virtual files in the
tree but new files aren't created virtual.
It's also a prelude for #6815
There's currently no way of
- upgrading vfs plugins (a silent suffix->winvfs upgrade is attempted
once only, when moving to master)
- disabling vfs capabilities outright
Unfortunately to do this, the local update phase must write to the
database, creating a new side-effect and order dependency (local update
must run before remote update).
Otherwise a interrupted or unsuccessful download would mean that the
download-intend was forgotten. The next sync would reestablish the
virtual file instead.
