Yesterday I merged a patch to PackageKit which added the UpgradeSystem() method to the transaction interface. This is the natural compliment of the GetDistropUgrades() method which was added last year. This allows a session user to upgrade the OS using the same familiar PackageKit tools, and without doing dumb things like asking for the admin pasword and running GTK and python graphically as the root user.
In Fedora, we use a package called preupgrade. This was created by Will Woods and Seth Vidal in 2008, and I was asked to maintain it last year. I’ve been helped by James Laska, which has been very much appreciated. Preupgrade has been fixed up a few times, but the majority of the code is the same as when I inherited it. Preupgrade was a nearly-good-enough monolithic lump of code that kinda worked.
In my humble opinion, Fedora (and all other distros) are too small to maintain such mission critical stuff such as distribution upgraders. The PackageKit project has shown people that by distributions combining forces, they can share frontends and write different small backends and free up developers for other things. As a team, we have a better quality product than the results of one developer on one distribution.
So I figured preupgrade should have the same love. 99% of the preupgrade code is GUI interface code and this was easily converted to C, and to use PackageKit. The result of this is in gnome-packagekit git master, with a new tool gpk-distro-upgrade.
Don’t go and try this code just yet. None of the preupgrade backend code has been moved to the yum backend, although I don’t assume I’ll have many problems, and plan to do this later in the week. If you want to test this use the “dummy” backend, although this won’t actually perform any changes of course.
Hopefully some of the other distros can play with gpk-distro-upgrade and improve it. Hopefully the translators will file bugs about the bad English, and translate it to 50 languages. Hopefully another distro will port their os updater to use this new functionality and find bugs or speed up the common code a little.
All I know is preupgrade will live on as part of PackageKit, and now it’s targeted at a bigger audience than just the few million of Fedora users.