Fellow packagers and pythonistas, i'd like to notify you about a proposed change to the way Python installs its packages, and give you a chance to object before it is put into effect. This has nothing to do with the "versioned python" proposal. TL;DR version: Currently, python is configured to install packages into /usr/local/lib/pythonX.Y/site-packages, unless you specify "--prefix=/usr". This mimicks autotools behavior, but diverges from upstream. If there are no significant objections, I'm going to restore the default behavior where "/usr" is the default prefix. Packages installed in /usr/local will still be recognized, it just won't be the default install location anymore. Detailed version: While investigating possible solutions to bnc#658604 (python user install scheme broken, [1]), i came to revisit the decision to make SUSE's python install modules into /usr/local by default. A little background: this feature came to be as a response to a pair of bugs, bnc#149809 [2] and bnc#149843 [3]. The original reporter argues that /usr/local is the right place for locally-installed software and that Python should not deviate from customary (i.e. autotools) behavior in this regard. Python should auto-recognize modules installed in the /usr/local hierarchy, and for consistency and convenience's sake, should install in there by default as well. The former request is reasonable, and back then i thought that the latter is reasonable as well. (also, back then i wasn't on the job for very long, i made the change, didn't tell anyone about it and broke about a million of other people's packages. oh those were the days. sorry again if you were affected.) Six years later, i still think it's the right thing to do, but i don't think we should actually be doing it. Arguments basically boil down to one of Python's core principles, "practicality beats purity". But for completeness, here's what i came up with. For installing to /usr/local: + it's what FHS tells us, with some good reasoning (read-only /usr and so on) + it's what autotools do + the /usr hierarchy remains untainted by files outside of rpm's control + and conversely, the user has all of her site-local packages in /usr/local, not mingled with "managed" installations (unlike e.g. Perl, Python has no official mechanism for separating "site" packages and "vendor" packages. this provides such distinction) Against: - AFAIK, we're the only ones doing it - upstream python doesn't recognize the distinction and there is no support for it in the libraries - to expand on that point, there is no "right" place to patch this behavior in - a correct patch for the new behavior wouldn't be too complex, but it would not be upstreamable. No patch is better than one patch. - modules don't like to be installed in locations they can't query through python's sysconfig methods - third-party python packagemanagers/installers might not recognize our intentions and would need to be patched separately Also, i'm not really aware of anyone reaping any benefits from our current config. So, if you have anything good to say about the way we do it now, here is your chance. I'll wait until next week, and if no significant objections are raised, i'll push this change into Factory. m. [1] "Python distutils setup does not allow user installation of Python packages" https://bugzilla.novell.com/show_bug.cgi?id=658604 [2] "python path does not contain /usr/local" https://bugzilla.novell.com/show_bug.cgi?id=149809 [3] "Python's site-packages should contain a directory in /usr/local" https://bugzilla.novell.com/show_bug.cgi?id=149843 -- To unsubscribe, e-mail: opensuse-packaging+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse-packaging+owner@opensuse.org