This PR adds support for locking files if the backend supports it.
To activate locking, set the option `--file-lock-duration=30D` and the backup will lock the files.
If the database is rebuilt with the intention of continuing the backups, use the option `--repair-refresh-lock-info` which will update lock information in the database after recreating the database.
The locking works by asking the backend to lock files after a backup has completed.
The implementation keeps track of which files are currently assigned a lock and prevents attempting to delete the files that are currently locked.
Note that the bucket should not have a default lock policy as Duplicati needs to finish the backup before the locking is applied.
In this initial version, Azure Blob Storage, B2, S3 and iDrive are supported with locking.
The CLI is updated to allow setting locks on a specific version. The backend tool is updated to allow setting locks on specific files.
* Rewrite the backend manager.
This creates a new more logic backend manager that handles all backend operations.
For each top-level operation, there is now a single backend manager instance that is passed to sub-commands.
The internals of the backend manager are now rewritten to use async logic instead of threading.
The design uses a single task runner that dispatches operations and honors concurrent settings and limits from one place.
The logic for each operation has been moved into a separate files/classes to make it easier to understand each operation.
This fixes#5804
* Fixed a few issues with not awaiting tasks
* Fixed not creating empty databases
* Fixed an issue with hashes not being recorded on download
* Reworked the download logic to avoid attempting to decrypt the file if it has been modified.
* Review fixes
* Renamed db collector to better reflect the purpose.
* Review fixes
Added a delete page with options to delete the local database, as well as the remote files.
Added a captcha to protect against automated attacks that would attempt to delete the remote files.
This fixes#1201