NIS optional module dependency

[Abgael]

NIS optional module build seems to fail if libnsl is missing. Installing libnsl-dev on Ubuntu/Debian or libnsl2-devel on Fedora based distros fixes the dependency issue.

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📚 Documentation preview 📚: https://cpython-devguide--1444.org.readthedocs.build/

[cpython-cla-bot]

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[skirpichev]

You can see above apt install & friends: "To install some additional dependencies for optional build and test components".

I.e. this is not an exhaustive list. Is there some reason why libnsl should be listed too?

[Abgael]

I don't think it necessarily should. It is more like a suggestion. The reason I am suggesting this is that with the guide given dependencies, the building process was able to build every single optional module, being NIS the only one to fail. Doing some search on the error message, (“The necessary bits to build these optional modules were not found:
nis”) I find out that other people bumped into the same problem.

[itamaro]

generally I'm in favor of having the optional dependencies as comprehensive as possible. the main reason for that, from my point of view at least, is that this is what I follow when setting up a buildbot worker, so having it as comprehensive as possible means that the buildbot will provide better coverage.

I'm unsure about this specific case, considering the nis module was removed in 3.13, so I wouldn't want stale optional dependencies listed.
it's a bit of a grey area since nis is still available up to 3.12, and we still run buildbots for 3.9+ branches.
my instinct would be to leave it out since it's deprecated and removed, but I wouldn't object to including it if others think it's valuable.

[encukou]

Thank you for the report, @Abgael!
As Itamar points out, the nis module was removed in 3.13. It was for good reasons. If you're building Python (any version) today, especially to help develop it, you're most likely better off without the nis module. If not, you probably know nis/libnsl2 and don't need the devguide to tell you what to do.
(For Buildbots: IMO, the existing fleet should keep nis covered until 3.12 goes EOL. As a back-up, Fedora builds and tests nis on 3.12 & below.)

With that, I'll close the issue. I hope it doesn't discourage you from contributing in the future!