Upgrade of snapshot not possible due to problem with files.snar (Errno 2 - file not found) + SOLUTION

[Thomas L.]

First of I would like to express that I'm quite disappointed by sbackup not being backwards compatible with 1.4 snapshots. When you are in need to restore a snapshot you more often than not don't have time for such stuff as "converting backups", which I generally think is a STUPID idea.

PLEASE MAKE THE RESTORE BACKWARDS COMPATIBLE!!!

Solution to the problem:
change line 1069 of /usr/share/sbackup/sbackup/ar_backend/tar.py from
fd = open(self.snpfile, 'w')
to
fd = _FOP.openfile_for_append(self.snpfile)

/home/mehm/.local/share/sbackup/backups/ is a soft link to /media/edb
/dev/sdf1 931G 772G 113G 88% /media/edb

Permissions:
/media/
drwxrwxr-x 9 mehm mehm 4096 Mai 17 14:47 edb

/media/edb/
drwxrwxr-x 2 mehm mehm 4096 Mai 17 18:42 2012-05-17_14.03.02.405114.elisabeth-desktop.ful

/media/2012-05-17_14.03.02.405114.elisabeth-desktop.ful/
insgesamt 143976920
drwxrwxr-x 2 mehm mehm 4096 Mai 17 18:42 .
drwxrwxr-x 9 mehm mehm 4096 Mai 17 14:47 ..
-rw-rw-r-- 1 mehm mehm 221 Mai 17 14:03 excludes
-rw-rw-r-- 1 mehm mehm 0 Mai 17 18:42 excludes.list
-rw-rw-r-- 1 mehm mehm 0 Mai 17 18:42 files.snar
-rw-rw-r-- 1 mehm mehm 147424042177 Mai 17 16:51 files.tar.gz
-rw-rw-r-- 1 mehm mehm 3352221 Mai 17 14:03 flist
-rw-rw-r-- 1 mehm mehm 6 Mai 17 18:42 format
-rw-rw-r-- 1 mehm mehm 1511291 Mai 17 14:03 fprops
-rw-rw-r-- 1 mehm mehm 3352221 Mai 17 18:42 includes.list
-rw-rw-r-- 1 mehm mehm 59192 Mai 17 16:51 packages
-rw-rw-r-- 1 mehm mehm 560 Mai 17 14:03 partitions
-rw-rw-r-- 1 mehm mehm 20 Mai 17 18:42 upgrade

2012-05-17 18:42:16,361 - DEBUG in restoregui._upgrade(806): Upgrade snapshot '2012-05-17_14.03.02.405114.elisabeth-desktop.ful'
2012-05-17 18:42:16,361 - INFO: Upgrading snapshot '2012-05-17_14.03.02.405114.elisabeth-desktop.ful' to version '1.5'
2012-05-17 18:42:16,361 - INFO: Umstellung auf v1.5: 2012-05-17_14.03.02.405114.elisabeth-desktop.ful
2012-05-17 18:42:16,369 - INFO: file:///home/mehm/.local/share/sbackup/backups/2012-05-17_14.03.02.405114.elisabeth-desktop.ful/files.tgz
2012-05-17 18:42:16,370 - INFO: renaming file.tgz to file.tar.gz
2012-05-17 18:42:16,371 - INFO: Creating includes.list
2012-05-17 18:42:25,866 - INFO: Creating empty excludes.list
2012-05-17 18:42:25,867 - INFO: Creating 'format' file
2012-05-17 18:42:25,867 - INFO: Creating the SNAR file
2012-05-17 18:42:25,867 - ERROR in restoregui._upgrade(813): Error while upgrade snapshot: [Errno 2] Datei oder Verzeichnis nicht gefunden: 'file:///home/mehm/.local/share/sbackup/backups/2012-05-17_14.03.02.405114.elisabeth-desktop.ful/files.snar'
Traceback (most recent call last):
  File "/usr/share/sbackup/sbackup/ui/restoregui.py", line 807, in _upgrade
    um.upgradeSnapshot(self.currentSnp)
  File "/usr/share/sbackup/sbackup/core/UpgradeManager.py", line 107, in upgradeSnapshot
    self.__upgrade_v15(snapshot)
  File "/usr/share/sbackup/sbackup/core/UpgradeManager.py", line 306, in __upgrade_v15
    snarfileinfo.setHeader(datet)
  File "/usr/share/sbackup/sbackup/ar_backend/tar.py", line 1401, in setHeader
    self.__snapshotFile.setHeader(timeofBackup)
  File "/usr/share/sbackup/sbackup/ar_backend/tar.py", line 1069, in setHeader
    fd = open(self.snpfile, 'w')
IOError: [Errno 2] Datei oder Verzeichnis nicht gefunden: 'file:///home/mehm/.local/share/sbackup/backups/2012-05-17_14.03.02.405114.elisabeth-desktop.ful/files.snar'
2012-05-17 18:42:25,879 - DEBUG in restoregui.load_snapshotslist(589): Selected day : 2012-05-17
2012-05-17 18:42:25,880 - INFO: Ungültige Sicherung `lost+found` gefunden: Name der Sicherung ist nicht gültig.
2012-05-17 18:42:25,884 - INFO: Ungültige Sicherung `2012-05-01_18.40.17.967610.elisabeth-desktop.ful` gefunden: Die notwendige Datei `ver` konnte nicht gelesen werden.
2012-05-17 18:42:25,886 - INFO: Ungültige Sicherung `2012-03-13_22.11.18.542077.elisabeth-desktop.ful` gefunden: Die notwendige Datei `ver` konnte nicht gelesen werden.
2012-05-17 18:42:25,887 - INFO: Snapshot `2012-05-17_14.03.02.405114.elisabeth-desktop.ful` is being upgraded. Skipped.

[Jean-Peer Lorenz (peer.loz)]

Hello Thomas,

thank you for using sbackup and reporting this issue!

You are absolutely right! Touching existing snapshots is a BAD idea and upgrading them is highly not recommended.

> PLEASE MAKE THE RESTORE BACKWARDS COMPATIBLE!!!
I am working on this and there is basic support for reading and writing arbitrary snapshot versions in my current development branch. Unfortunately, I'm short on time and cannot tell any release date when this will be finished. Help is highly appreciated.

Thank you for your help and sorry for any inconvenience!

Best regards,
Jean-Peer