[tahoe-dev] [tahoe-lafs] #848: "tahoe backup": --prefix argument

[tahoe-lafs]

#848: "tahoe backup": --prefix argument
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 Reporter:  warner             |           Owner:           
     Type:  enhancement        |          Status:  new      
 Priority:  major              |       Milestone:  undecided
Component:  code-frontend-cli  |         Version:  1.5.0    
 Keywords:                     |   Launchpad_bug:           
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 I think it might be useful to add a --prefix argument to the "{{{tahoe
 backup}}}" command, which would basically strip that prefix from any
 absolute pathnames before checking the backupdb for a previously backed up
 file. This would help the use case where you mount an external drive in
 one place (say /Volumes/One), use "tahoe backup" to copy it into tahoe,
 and later mount the same drive in a different place (say /Volumes/Two) and
 want to do a backup again.
 If the mount point is variable, you'd probably want the backupdb contents
 to be compared against the per-drive path, not the mount-point-plus-drive
 path. Also, if you mounted a *different* drive under /Volumes/One, you
 might want to exclude those paths from the backupdb check. This might
 suggest that the backupdb really ought to use mount-point-relative
 pathnames, or parent directory inode number, or something more accurate
 and durable than absolute pathname.

 Another use case would be if you want to back up a Time Machine snapshot
 (named /backupdrive/snapshots/Tuesday) and then do the same backup on the
 next snapshot (named /backupdbdrive/snapshots/Wednesday). (you could
 backup the "Latest" directory, but this might change while you're running
 the backup, whereas the timestamped snapshot directory is immutable.

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Ticket URL: <http://allmydata.org/trac/tahoe/ticket/848>
tahoe-lafs <http://allmydata.org>
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