Make torch and some other dependencies optional

[meakbiyik]

Hi, kudos to your work as this package will be quite useful. However, it was quite a bad surprise for me to add this package to my project dependencies and see huge and non-environment-friendly packages such as pytorch, gpytorch, llvmlite and even plotly being installed into my environment. I only plan to use some changepoint detection methods and maybe visualizations, and I highly doubt that (though, of course correct me if I am wrong) the whole torch stack is necessary for such a task. Similarly, I imagine plotly can easily be made an optional dependency as well, since matplotlib is still the de facto plotting library of python and it would not be in the interest of majority of the users to install a data analysis package and get a big python-js bundle with it.

[michaelbrundage]

Thanks for reporting this. I've fixed this in f6d9d94. pip doesn't have a way for us to keep pip install kats the default and allow users to optionally opt-out of some functionality; only the opposite. So, to get a reduced version of Kats without Pytorch, plotly, and many other packages (everything listed in test_requirements.txt), you can now use

MINIMAL=1 pip install .

from the root level of the Kats source, and in the future (after we release the next version of Kats),

MINIMAL=1 pip install kats

If you later decide you want some of those additional functionalities, you can manually install the ones you want, or install all of them with

pip install -r test_requirements.txt

[meakbiyik]

@michaelbrundage thanks for the quick resolve. One question though: why not poetry? I thought it was becoming kind of an industry standard by now, and you can add both the optional tag to packages, and also bundle them with extras flexibly. Also since it is PEP 517 compliant, the whole previous pipeline with pip will continue to work.

An example from a package I have written: the CLI component is optional, so those packages are marked as optional and can be installed by specifying the cli extra during install (or after install): pip install [blah] -E cli .

[michaelbrundage]

@meakbiyik The goal was to remove dependencies, not add a new one. However, PRs always welcome. Kats would need a pyproject.toml first, and need to install smoothly across all platforms we support.

[adamantike]

@michaelbrundage, for people using this project and installing it within their own requirements.txt file, would you consider having a more specific environment variable, as that would be the only alternative if they want a minimal installation of kats but not of the rest of their dependencies (in case any other one also considers the MINIMAL variable)?

A small change like this one would be everything we need to avoid any undesired side effects on our installation process:

if not os.environ.get("MINIMAL", False) and not os.environ.get("MINIMAL_KATS", False):
    install_requires += extra_requires

[michaelbrundage]

Thanks for the PR. Is there any reason to add a second variable, or should we just rename the one variable from MINIMAL to MINIMAL_KATS to avoid potential conflicts with any other projects?

Can you point to any examples of other projects that use the MINIMAL variable?