[packagekit] package reinstallation

[Michal Minář]

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On 07/07/2014 05:49 PM, Richard Hughes wrote:
> On 7 July 2014 16:21, Michal Minář <miminar at redhat.com> wrote:
>> The thing is that our previous implementation used yum as a
>> backend. We've covered most of its functionality and *reinstall*
>> is one of its commands. Now we'd like to have PackageKit-based
>> implementation supporting all the features of the former one.
> 
> But why? What problem are you expecting re-install to fix?
As a devel, I overwrite system files quite often. It may be a system
library, configuration file or some shared resource. With an option to
reinstall affected package, there is no need to make a backup and
replace the modified files with original ones afterwards. Reinstall is
easy, quick and reliable (if I have the package downloaded). Another
use case is a package with an application managing its own database
(tog-pegasus for example). Sometimes it's very easy to corrupt it and
make the app unusable - it maybe just a bug in a registration script. On
a production system a backup is a necessity but on devel or testing
system, reinstall is a way to go. Maybe I'm doing it wrong but I have to
say that without reinstallation, my work would get more troublesome.
> 
>> I see it as a problem of backend to solve the dependencies and
>> security gotchas.
> 
> There's a significant amount of policy required on how to handle 
> downgrading. It's further complicated as distros like fedora only 
> carry the latest version of a package on the mirrors, so you have
> to go hunting for an old mirror which is further complexity, and
> also a security risk as the mirrors have to be treated as
> untrusted.
Dependency handling is IMHO the problem of a backend. If dependencies
can't be resolved, downgrade will fail. User still should have an option
to specify all the dependencies with desired versions himself.

As mentioned before by Daniel N., calling install() with older version
is sufficient for me. Perhaps some 'Force' flag could be added that
would help backend decide whether reinstall or downgrade shall be
allowed.
> 
>> You are right. This is a fairly common use case though.
> 
> It is? What actual uses cases can you identify? I couldn't see
> many requirements from those bugzillas you linked, but only looked
> quickly. Thanks.
> 
> Richard. _______________________________________________ PackageKit
> mailing list PackageKit at lists.freedesktop.org 
> http://lists.freedesktop.org/mailman/listinfo/packagekit
> 

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