[Catalog-sig] Standardized way of getting to a package download URL in Cheeseshop

[Grig Gheorghiu]

--- "Phillip J. Eby" <pje at telecommunity.com> wrote:

> At 01:33 PM 11/9/2005 -0800, Grig Gheorghiu wrote:
> >I'm working on a project I called "Cheesecake" which aims to
> quantify
> >the "goodness" of Python packages based on various indicators such
> as
> >presence of special files (README, LICENSE, etc.), special
> directories
> >(tests, doc, etc.), percentage of modules/classes/methods/functions
> >with docstrings, etc.
> >
> >It would be nice if there was a standardized way to get to a
> download
> >URL for a given package listed at the Cheeseshop.
> 
> setuptools' "package_index" module has facilities to scan Cheeseshop
> pages 
> and the pages they link to for URLs that are downloadable 
> distributions.  Also, the "easy_install" command-line tool can be
> used to 
> fetch and extract editable source (or check out from subversion) the
> source 
> code of a project.  For example:
> 
>      $ easy_install -eb~/projects SQLObject
>      Searching for SQLObject
>      Reading http://www.python.org/pypi/SQLObject/
>      Reading http://sqlobject.org
>      Best match: SQLObject 0.7.0
>      Downloading 
>
http://cheeseshop.python.org/packages/source/S/SQLObject/SQLObject-0.7.0.tar.gz#md5=dccb921b5df6a15312b56630ac4ac205
>      Processing SQLObject-0.7.0.tar.gz
> 
>      Extracted editable version of SQLObject to ~/projects/sqlobject
> 
> Notice that this works even with projects not hosted at the
> Cheeseshop, 
> even if they are on Sourceforge mirrors:
> 
>      $ easy_install -eb~/projects ctypes
>      Searching for ctypes
>      Reading http://www.python.org/pypi/ctypes/
>      Reading http://starship.python.net/crew/theller/ctypes/
>      Reading
> http://sourceforge.net/project/showfiles.php?group_id=71702
>      Best match: ctypes 0.9.6
>      Downloading 
> http://prdownloads.sourceforge.net/ctypes/ctypes-0.9.6.zip?download
>      Requesting redirect to (randomly selected) 'surfnet' mirror
>      Downloading 
> http://surfnet.dl.sourceforge.net/sourceforge/ctypes/ctypes-0.9.6.zip
>      Processing ctypes-0.9.6.zip
> 
>      Extracted editable version of ctypes to ~/projects/ctypes
> 
> As long as a download link is available from one of these three
> places, it 
> can be found:
> 
>   1. The cheeseshop page for the package
>   2. The page referenced by the cheeseshop "download url" link
>   3. The page referenced by the cheeseshop "home page" link
> 
> I would say that any project whose download URL(s) can't be found by 
> easy_install should get a bad score on your metrics, since it's going
> to be 
> pretty tough for the *user* to find the package!
> 
> EasyInstall is not limited to source downloads, however.  It's just
> that 
> the '-e' option tells it you want an "editable" distribution (e.g., a
> 
> Subversion checkout preferably, with a source distribution being
> second 
> best), and the '-b' option tells it the base directory under which
> the 
> project directory should be created.  (Ordinarily, EasyInstall just 
> attempts to get binaries or build and install them.)
> 
> 

Thanks a lot for the explanation, this is exactly what I was looking
for! Once again EasyInstall saves the day :-)

Grig