[Distutils] Beyond wheels 1.0: helping downstream, FHS and more

[David Cournapeau]

Hi there,

During pycon, Nick mentioned there was interest in updating the wheel
format to support downstream distributions. Nick mentioned Linux
distributions, but I would like to express interest for other kind of
downstream distributors like Anaconda from Continuum or Canopy from
Enthought (disclaimer: I work for Enthought).

Right now, wheels have the following limitations for us:

1. lack of post/pre install/removing
2. more fine-grained installation scheme
3. lack of clarify on which tags vendors should use for custom wheels: some
packages we provide would not be installable on "normal" python, and it
would be nice to have a scheme to avoid confusion there as well.

At least 1. and 2. are of interest not just for us.

Regarding 2., it looks like anything in the <wheel_name>.data/data
directory will be placed as is in sys.prefix by pip. This is how distutils
scheme is defined ATM, but I am not sure whether that's by design or
accident ?

I would suggest to use something close to autotools, with some tweaks to
work well on windows. I implemented something like this in my project bento
(
https://github.com/cournape/Bento/blob/master/bento/core/platforms/sysconfig.py),
but we could of course tweak that.

For 1., I believe it was a conscious decision not to include them in wheel
1.0 ? Would it make sense to start a discussion to add it to wheel ?

I will be at the pycon sprints until wednesday evening, so that we can
flesh some concrete proposal first, if there is enough interest.

As a background: at Enthought, we have been using eggs to distribute
binaries of python packages and other packages (e.g. C libraries, compiled
binaries, etc...) for a very long time. We had our own extensions to the
egg format to support this, but I want to get out of eggs so as to make our
own software more compatible with where the community is going. I would
also like to avoid making ad-hoc extensions to wheels for our own purposes.

thanks,
David
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/distutils-sig/attachments/20150413/ae73e7b9/attachment.html>