SIGs/KDE/Backup Solution

= Backup Solution for the KDE Live CD =

Problem space: The current KDE live image doesn't include any dedicated backup solution.

Use cases for a dedicated backup solution
Some of the use cases can be fulfilled by other apps:
 * file managers (Dolphin, Krusader if we ship it)
 * archivers (Ark)
 * Konsole ;-) (not really suitable for new users)

The questions to ask first are:
 * What use cases are there for backups?
 * Which of them are not covered by the above existing apps?
 * Which are technically covered, but can be served better by dedicated apps?
 * How well does the proposed dedicated backup app cover the use cases?

The result of this evaluation should be:
 * Is a dedicated backup solution needed/useful?
 * Which solution is most worth shipping?
 * Do we even want to ship more than one solution (e.g. one based on rsync and one based on tar, which have mostly non-overlapping use cases)?
 * Do we have room on the CD for the added package(s)? If not, what other app do we remove to make room for them?

Feature Wishlist
A list of features we would like to see in an ideal backup app:
 * 1) an efficient way to track which files were modified since the last backup (cached file dates, sizes and/or checksums, possibly snapshots on BTRFS)
 * 2) support for at least local cp, scp/sftp, ftp and rsync as targets
 * 3) ad 2., rsync only the files which have been found to have changed due to 1.
 * 4) support for tarring (or zipping or something) the files, including updating existing archives (ideally also remotely with a server component)
 * 5) support for xz-compressing files (to support 4. efficiently, something like a tar of xz-compressed files would probably be more appropriate than something like tar.xz)
 * 6) support for backing up entire partitions
 * 7) support for doing operations as root using KAuth (or PolicyKit directly), with permissions as fine-grained as possible (i.e. if it's possible to separate a backup from privileged to non-privileged from a restore from non-privileged to privileged resp. from an entirely privileged transaction, do so), but in any case not running the entire app as root, which is deprecated
 * 8) a decent native KDE GUI using the KDE icon loader and standard XDG icon theme icons
 * 9) a text-mode UI to use in emergency situations

Unfortunately, none of the proposed solutions even come close to that feature set. The important considerations are:
 * which of those features are essential and which are just nice to have,
 * whether there are other (possibly even more important) requirements and
 * how well the existing apps fulfill the requirements.

Candidates for Inclusion
This section lists candidate backup solutions and evaluates their advantages, drawbacks and possible improvements to suggest to the upstream project.

luckyBackup
luckyBackup is based on rsync.

[TODO: Pros/cons/wishes.]

luckyBackup is already packaged in Fedora.

KBackup (kde-apps.org)
KBackup is based on tar.

[TODO: Compare with Ark which is already included. Determine pros/cons/wishes.]

KBackup is already packaged in Fedora.