[schooltool-dev] additional data.fs's

[Ignas Mikalajunas]

On Fri, Dec 12, 2008 at 15:31, Tom Hoffman <tom.hoffman at gmail.com> wrote:
> On Fri, Dec 12, 2008 at 5:27 AM, Ignas Mikalajunas <ignas at pov.lt> wrote:
>> On Fri, Dec 12, 2008 at 00:39,  <jason.straw at gmail.com> wrote:
>>> Can I suggest that we name those by evolution number/date?  otherwise the numbers have no meaning.
>>>
>>
>> At the moment backup is kind of hacky, as we are using the log
>> roration script, so if you know how to write a reliable backup script
>> that also manages to find out the evolution number (we only have sh in
>> postinst script) or at least format a date nicely, and gzip the backup
>> - I'd gladly accept a patch. Just apt-get source schooltool-common and
>> look for the postinst script template if you want to see how
>> not-nicely it is being performed now...
>
> Does it automatically gzip the second most recent backup or something?
>  I'm just not sure about the pattern (I need to explain this in the
> docs).
>
> --Tom
>

At the moment the workflow is this:

If you have Data.fs, Data.fs.0, Data.fs.1.gz

Rename Data.fs.1.gz to Data.fs.2.gz, Gzip Data.fs.0 as Data.fs.1.gz,
move Data.fs to Data.fs.0, copy Data.fs.0 to Data.fs

Which is broken in one respect: if something happens - you run out of
space, hit Ctrl-C, kill apt in some place, you end up with your
Data.fs moved to Data.fs.0 and no Data.fs at all (so school tool
startup would create an empty Data.fs thus breaking the application as
far as users are concerned)

OTOH - maybe we don't want users to mess with unbacked up Data.fs, I
mean - maybe running an evolution script without backup is worse than
failing to start up properly if backups failed...

Ignas