I have a few Python packages that I would like to tidy up and publish on PyPI. These packages import a couple of Python modules I’ve written to augment or simplify certain operations (e.g., reading/writing from CSV files with headers by wrapping csv functions), provide handy data structures, etc. Currently these modules are housed in the top-level directory that holds the code for my projects, and I rely on reaching them by having added that directory to my PYTHONPATH environmental variable. (Less than tidy, I know.)
By creating a separate package for these modules and uploading them on PyPI, I could mark such a package as a dependency for the packages I actually want to distribute. These convenience modules are, however, small and of limited use and interest, such that I don’t think they warrant distributing as a separate package on PyPI. On the other hand, I am hesitant to copy these convenience modules (i.e., use cp convenience_module.py projectX/.) into each project directory, as this creates multiple copies of the same file both in the VCS repository housing my Python code and in the different source distribution tarballs I would post to PyPI. Is there an elegant solution to this problem?
You don’t say why you’re hesitant to ‘provide copies’. In general, I think a reasonable approach is to think about how you’ve set things up for yourself to use the convenience modules. Did you install them in site-packages (or equivalent), or did you just depend on them being in the directory you ran the code from? However you use the modules, is that situation ideal, or is there a way that would be nicer for you?
Start with that, and figure out how to automate it through setup.py, which lets you put things wherever you want on the system (though I strongly discourage abusing this capability).
Whether you distribute them as a tarball or with the package that needs them, you still have to maintain all of the files, so the only real question is whether you intend for those convenience modules to develop their own user communities with their own support requests, etc., or whether they’re decidedly intended only for use in support of this other module.
If you intend those modules to be used only for the one module, include them in the package, perhaps in a ‘utils’ package inside the distribution. Otherwise you’re just cluttering the index with things people might think are useful, but are really joined at the hip with something else that drives the changes and maintenance of them.
If you intend those modules to be generic, and intend to maintain them as such, and think they have use outside of supporting this module, distribute them separately.