[Python-Dev] PEP 365 (was Re: PEP: per user site-packages directory)

[Phillip J. Eby]

At 01:06 AM 1/22/2008 +1000, Nick Coghlan wrote:
>Steve Holden wrote:
> > Christian Heimes wrote:
> >> Steve Holden wrote:
> >>> Maybe once we get easy_install as a part of the core (so there's no need
> >>> to find and run ez_setup.py to start with) things will start to improve.
> >>> This is an issue the whole developer community needs to take seriously
> >>> if we are interested in increasing take-up.
> >> setuptools and easy_install won't be included in Python 2.6 and 3.0:
> >> http://www.python.org/dev/peps/pep-0365/
> >>
> > Yes, and yet another release (two releases) will go out without easy
> > access to the functionality in Pypi. PEP 365 is a good start, but Pypi
> > loses much of its point until new Python users get access to it "out of
> > the box". I also appreciate that resource limitations are standing in
> > the way of setuptools' inclusion (is there something I can do about
> > that?) Just to hammer the point home, however ...
>
>Have another look at the rationale given in PEP 365 - it isn't the
>resourcing to do the work that's a problem, but the relatively slow
>release cycle of the core.
>
>By including pkg_resources in the core (with the addition of access to
>pure Python modules and packages on PyPI), we would get a simple, stable
>base for Python packaging to work from, and put users a single standard
>command away from the more advanced (but also more volatile) features of
>easy_install and friends.

By the way, if we're actually going to get that into 2.6, it would be 
good for the PEP to actually be approved before then.  :)

With respect to Steve's comments about out-of-the-box usability, it 
should be noted that when you bootstrap a package with pkg_resources, 
it should be possible to include other command-line arguments after 
the package specifier.  So for example:

     python -m pkg_resources setuptools SomePackage==1.2

would download and install setuptools, and run its "bootstrap script" 
with "SomePackage==1.2" as a command-line argument.  And setuptools' 
bootstrap script is basically easy_install with some extra code to 
make sure the setuptools egg gets installed too.

In other words, with PEP 365 in place, "python -m pkg_resources 
setuptools" is basically a way to say "easy_install" without needing 
setuptools installed.

(Heck, if what you really want is to have easy_install support in 
2.6, we could just as easily bundle an easy_install.py that asks for 
an install of setuptools if it's not already present.)