Tarek Ziadé wrote:
On Fri, Jan 30, 2009 at 10:28 AM, David Cournapeau <david@ar.media.kyoto-u.ac.jp> wrote:
I can see several things which have a big impact on an uninstall feature design: - how to handle multiple versions of one package ? - should it handle dependencies ?
from a distutils point of view, none of these features exist. My opinion is that the multiple version and the dependencies matters should be treated separately, because the atomic part is the package.
agreed
And if you know how to uninstall a package, it's the basis of a meta-uninstaller.
Not necessarily: many package systems simply do not deal at all with multiple versions. This really complicates the matter a lot right away whether that's something which needs to be supported, even if it is not supported by the tool itself. IOW, ignoring the problem in distutils may well render any multiple version handling impossible for tools build on top of distutils.
- should it work for packages installed anywhere, or only for a few reserved places ?
It should work for any package installed. Wherever it's installed. If it's in the path and usable in Python, it should be removable.
Again, that's a major complication - so if it is required, it should really be weight against the implementation and reliability cost. For example, I am somewhat familiar with the following systems used for deployment: autoconf-based, .deb based, .net based, stow-based, windows Side by side, globac assembly cache (GAC, the .net stuff). AFAIK, not a single one supports both multiple versions deployment and arbitrary installation location. That should at least be an indication this is not a trivial matter.
My opinion is that distutils and pkgutil should provide a set of apis to:
- locate a package (see http://bugs.python.org/issue4908) - install / uninstall a package
Then two simple basics commands could be offered in Python executable scripts.
From there any third party app could have fun adding a better UI
But my point is that the logic behind install/uninstall should be unique and clearly defined and in one and only one place (e.g. Python) to avoid having many different ways to deal with those problems.
100 % agreed. My remark was just that uninstalling may require asking some questions to the user depending on the system state, so a distutils uninstall command at the UI level may not be advisable . Of course, the actual implementation for uninstalling should be done in distutils itself, with a *documented* API so that other tools can be built on top of it. David