[Distutils] PEP for dependencies on libraries like BLAS

[Reinout van Rees]

Op 18-09-15 om 02:15 schreef Tennessee Leeuwenburg:
> Regarding 'boil the ocean' -- I think that's only true when this PEP 
> is taken to be trying to "solve all dependency interactions". In fact, 
> it's more about letting authors handle common, known issues on 
> specific platforms. That's my view anyway. I know if I had this for my 
> packages, just having one or two of these declared would handle a lot 
> of problems.
Perhaps a simple test case would be to get certain packages to 
work/build/test on travis-ci.org.

I've spend quite some hours this week to get one of my own packages to 
build there and I didn't succeed.
Well, let me rephrase that: I managed to get three packages working 
without any real problems, but one of them defied my efforts.

It is the typical difficult usecase of a package that needs psycopg2, 
mapnik, matplotlib, PIL(LOW), numpy, scipy and so.
I use buildout with the "syseggrecipe" that can re-use globally 
installed packages.
I could install psycopg2 with pip by first de-activating the standard 
travis-ci virtualenv.
With the new sudo-less infrastructure I could install matplotlib and 
numpy globally with an apt-get call.
My memory is fuzzy right now, but I think I also installed two libraries 
from within buildout after installing the appropriate header files.
Only mapnik failed because I couldn't install some header files and 
there was no wheel and other alternatives failed, too.

In any case: such a mix of wheel/apt-get/compile with several tools 
should ideally be stripped down to just one or two methods.

Reinout

-- 
Reinout van Rees                          http://reinout.vanrees.org/
reinout at vanrees.org                   http://www.nelen-schuurmans.nl/
"Learning history by destroying artifacts is a time-honored atrocity"