Is there a standard way to list names of Python modules in a package?

DNS picture DNS · Jan 28, 2009 · Viewed 84.6k times · Source

Is there a straightforward way to list the names of all modules in a package, without using __all__?

For example, given this package:

/testpkg
/testpkg/__init__.py
/testpkg/modulea.py
/testpkg/moduleb.py

I'm wondering if there is a standard or built-in way to do something like this:

>>> package_contents("testpkg")
['modulea', 'moduleb']

The manual approach would be to iterate through the module search paths in order to find the package's directory. One could then list all the files in that directory, filter out the uniquely-named py/pyc/pyo files, strip the extensions, and return that list. But this seems like a fair amount of work for something the module import mechanism is already doing internally. Is that functionality exposed anywhere?

Answer

jp. picture jp. · Aug 21, 2009

Using python2.3 and above, you could also use the pkgutil module:

>>> import pkgutil
>>> [name for _, name, _ in pkgutil.iter_modules(['testpkg'])]
['modulea', 'moduleb']

EDIT: Note that the parameter is not a list of modules, but a list of paths, so you might want to do something like this:

>>> import os.path, pkgutil
>>> import testpkg
>>> pkgpath = os.path.dirname(testpkg.__file__)
>>> print [name for _, name, _ in pkgutil.iter_modules([pkgpath])]