Python: Finding all packages inside a package

Question

Given a package, how can I automatically find all its sub-packages?

Answer 1

You can't rely on introspection of loaded modules, because sub-packages may not have been loaded. You'll have to look at the filesystem, assuming the top level package in question is not an egg, zip file, extension module, or loaded from memory.

def get_subpackages(module):
    dir = os.path.dirname(module.__file__)
    def is_package(d):
        d = os.path.join(dir, d)
        return os.path.isdir(d) and glob.glob(os.path.join(d, '__init__.py*'))

    return filter(is_package, os.listdir(dir))