使用zc.buildout时遇到有关双重导入pkg_resources的“ UserWarning”

Question

when I run bin/buildout , the warning repeated like this:

/Users/healdream/Playground/python/buildout/parts/buildout/site.py:262: UserWarning: Module pkg_resources was already imported from /System/Library/Frameworks/Python.framework/Versions/2.6/Extras/lib/python/pkg_resources.py, but /Users/healdream/Playground/python/buildout/eggs/distribute-0.6.19-py2.6.egg is being added to sys.path
  import pkg_resources

I use zope's bootstrap.py and before run bin/buildout , I run python bootstrap.py --distribute

in bootstrap.py, pkg_resources is imported, and in bin/buildout parts/buildout is prepended to sys.path

sys.path[0:0] = [
    '/Users/healdream/Playground/python/buildout/parts/buildout',
    ]

in parts/buildout/site.py:262, pkg_resources is explicitly imported again import pkg_resources . so the warning appears.

how to avoid the warning?

Answer 1

It was probably a isolation issue which was only addressed by the upgrade because it replaced the base installation. If it happens again, trying a virtualenv is a good idea:

$ virtualenv --no-site-packages .
$ bin/python bootstrap.py
$ bin/buildout