[Rpm-maint] Removing repackage and (auto)rollback?

[Panu Matilainen]

On Thu, 21 Feb 2008, Pixel wrote:

> Panu Matilainen <pmatilai at redhat.com> writes:
>
>> Before anybody asks: I actually do think that ultimately rpm should be able to
>> support reliably rolling back transactions. It's just that the current
>> repackage+rollback combo fails to deliver it, as there's no way to undo script
>> actions.
>
> for info, some Mandriva users are using the feature (see quotes
> below), but still, Mandriva is not pushing it strongly, and dropping
> it would not be a big loss.

Ok.

> -------------------------------------------------------------------------
>> anyone using repackage/rollback in rpm?
>
> sometimes.
> often broken (generating broken packages in /var/spool/repackage with
> buggy CRC (mismatch between old & new packages' content & CRC?)

Actually the repackaged packages are deliberately poisoned so that nobody 
thinks they're real packages that could be further distributed. The 
repackaged package is not the same as the original: it's contents may have 
been modified in any arbitrary way, including files removed, prelinked, 
contents otherwise modified etc.

>> anyone using urpmi --repackage or urpmi.recover?
>
> I _once_ used --repackage. Never used urpmi.recover
> -------------------------------------------------------------------------
> Rick James (until recently working with me on the forums, now doing it
> on a volunteer basis) uses urpmi.recover regularly and encourages users
> to use it. See http://forum.mandriva.com/viewtopic.php?p=439429 , for
> example. Another forum member, K Bergen, has made references to using
> it: see http://forum.mandriva.com/viewtopic.php?p=403897 . Other users
> who have been referred to the tool by these two have expressed an
> interest in trying it. I remember yesterday someone mentioning that
> they'd tried to use it but had it fail three times.
>
> Based on the above I'd say there's clearly a demand for urpmi.recover ,
> and a non-zero quantity of people using it right now.

I don't disagree at all. I just think that the vast majority of the users 
actually just want rollback/recover as in downgrade to previous version 
when the latest upgrade broke something, essentially rpm -Uvh 
--oldpackage <previous version>. Of course the old package needs 
to be somewhere available for you to be able to do that, but instead of 
rpm creating packages with busted up contents, you could use the upper 
level depsolver to cache all downloads (no more diskspace wasted than with 
--repackage) and downgrade at request.

I think practically all depsolvers offer the caching option already, any 
many if not all support downgrading too. What's missing is version history 
information, ie "revert selected/all packages to whatever versions they 
had yesterday because todays update broke stuff", rpmdb only stores the 
installation date, not version history.

 	- Panu -