[Distutils] PEP 376 and the name .egg-info?

[P.J. Eby]

At 06:11 PM 3/23/2009 -0700, Kevin Teague wrote:
>I have some confusion over the name .egg-info. From what I understand,
>Eggs are a packaging format that contain metadata. But if you take a
>Distutils installed package and put a .egg-info file or directory
>beside it, that doesn't make the package an Egg, does it?

Yes, actually, it does.  See 
http://peak.telecommunity.com/DevCenter/EggFormats for details.


>To add to this confusion, I always associate the Egg format with the
>additional metadata fields provided by setuptools. So when I see 
>.egg- info I always expect that the PKG-INFO will contain an
>'install_requires' field, etc.

That information is maintained separately, as there's more tracked by 
setuptools than distutils and the formats are not compatible.  Also, 
PKG-INFO is generic for a project as a whole, whereas the 
egg-specific dependency info can vary by python version and/or platform.


>I guess that PEP would entail a little more work than just managing a
>set of fields since PyPI would also need to be updated to display
>those fields. But it would be really lovely to be able to see the
>'install_requires' field when browsing PyPI - and click on links in
>that field to take you to those pakcages PyPI pages. And as an added
>bonus if the 'namespace_packages' field was clickable such that the
>link took you to a list of all packages which participated in that
>namespace, that'd be pretty sweet!

The formats of this information are documented in EggFormats, and 
it's certainly possible for the PyPI software to pull the data from 
the sdist and/or egg files.  But someone would have to supply the 
patches to implement this.