Feature proposal: backup classes

[Gavin Carr]

One feature that's available in most other backup systems, and
currently missing in brackup, is the ability to distinguish 'classes'
of backup (like monthly/weekly/daily), and prune or rotate separately
within those classes. 

I'd like, for instance, to able to tag the first backup of the month 
as a 'monthly', and have those backups ignored in the standard prune.
Or do monthlies and weeklies and dailies, say, and keep all monthlies, 
8 weeklies, and 30 dailies, or whatever.

I think this would just be a matter of adding the notion of a 'class' 
to a backup, and modifying prune to be class-aware (perhaps initially 
just operating on a single class). I'd imagine you'd keep the current
behaviour by allowing a 'null' class that's used if one isn't 
specified.

I believe brackup-target list_backups and prune just look at the 
brackup file name and metadata rather than looking at its contents, so 
we probably want to encode a classname in the brackup filename to 
keep this behaviour. Perhaps we could just append a class, if given,
to the brackup file name, like this:

  home-1233494128.brackup
  home-1233548070-daily.brackup
  home-1233704988-monthly.brackup

which would display in list_backups as:

  home-1233494128           Mon 02 Feb 2009 00:20:12         31034846
  home-1231679729-daily     Mon 12 Jan 2009 00:20:01         30507171
  home-1228050927-monthly   Mon 01 Dec 2008 00:19:10         29264710

Thoughts/comments? 

I'm happy to produce some code if there's general agreement on the 
concept.

Cheers,
Gavin


-- 
Gavin Carr
- http://www.openfusion.com.au - Linux, Perl, and Web Consulting
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