packaging common python namespaces

Question

I'm looking to package and upload a library I have to PyPI in the next few days, but I'm a little unsure about my approach to the namespace.

I have a few otherwise unrelated projects with a similar approach and wanted to give them all the same namespace. For example:

• Library 1 namespace: abc.seo
• Library 2 namespace: abc.ajax
• Library 3 namespace: abc.ecommerce
• etc

The problem is that I'm not sure if it's possible for two separate packages (eg eggs) to co-exist with the same parent namespace. Is this approach problematic, or is there a way around it? What's the best approach?

The libraries should not be packaged together, they are too unrelated. I would like to get it right before uploading so as to avoid painful namespace changes after making an "official" release.

^{(NB abc is not the real name, I wanted my question to be free from advertising)}

UPDATE

I went with the following, to be nice to the people without setuptools installed:

try:
 __import__('pkg_resources').declare_namespace(__name__)
except ImportError:
 __path__ = __import__('pkgutil').extend_path(__path__, __name__)

With the following in setup.py:

setup(
 ...
 namespace_packages = ['rollyourown'],
 ...

• S.Lott: Have you looked at the various eGenix mx packages on PyPi? Look at those for examples. Then you can ask more specific questions based on that pattern.
• Will Hardy: So you mean to say it's not problematic for a user to install two separate packages with the same parent namespace? This will never cause any issues? The mx packages appear to have a very complicated installation process, I'll try my best to see if they have any special workarounds for namespace issues.
• bukzor: Your "update" is in fact an answer, rather than an update of your question. I'd move it to be an answer, so we can vote on it :)

Answer 1

In each project base directory, create the following structure:

/setup.py
/abc/__init__.py
/abc/seo/

/abc/__init__.py contains :

__import__('pkg_resources').declare_namespace(__name__)

setup.py contains :

setup(...,
 packages: ['abc', 'abc.seo'],
 namespace_packages = ['abc']
 ...
)

Reference documentation: namespace packages.

• Will Hardy: Wonderful! This sounds like it solves the technical problem completely. Thanks!