[Distutils] setup.py --install-requires?

[P.J. Eby]

At 01:28 PM 4/8/2009 -0700, Sridhar Ratnakumar wrote:
>For example, zc.catalog declares these dependencies in its setup.py
>
>       install_requires=['ZODB3',
>                         'pytz',
>                         'setuptools',
>                         'zope.catalog',
>                         'zope.container',
>                         'zope.component',
>                         'zope.i18nmessageid',
>                         'zope.index>=3.5.1',
>                         'zope.interface',
>                         'zope.publisher',
>                         'zope.schema',
>                         'zope.security',
>                         ],
>
>Is it possible to reliably get this list in a custom Python code 
>without having to parse setup.py?

Something like this should do the trick:

import tempfile, os.path
from setuptools.sandbox import run_setup

def get_requires(setup_dir, empty_tmpdir):
     tmpdir = tempfile.mkdtemp(prefix="egginfotmp-")
     run_setup(os.path.join(setup_dir,'setup.py'), ['-e', tmpdir])
     for dist in pkg_resources.find_distributions(tmpdir, True):
         return dist.requires()
     else:
         raise RuntimeError("egg_info didn't work")

You'll get back a list of pkg_resources.Requirement objects rather 
than strings, but you can turn them back into strings if you like.