[OE-core] "inherit setuptools" versus "inherit pypi" -- a python style question

[Robert P. J. Day]

On Thu, 2 Mar 2017, Robert P. J. Day wrote:

>   possibly a "best practices" question ... regarding recipe for
> "python-psutil" (although this applies for numerous python recipes),
> wind river linux 8 has a recipe for python-psutil_2.2.1.bb which
> inherits pypi:
>
>   RDEPENDS_${PN} += " \
>     python-subprocess \
>     "
>
>   inherit pypi
>
> a newer recipe i ran across in-house that someone else set up,
> python-psutil_3.2.1.bb, instead inherits setuptools and gets the
> source from github:
>
>   inherit setuptools
>
>   # 3.2.1 tag
>   SRCREV = "99f6abf9bcff3abff815b8e93c8cd2fbe26487a2"
>   SRC_URI = "git://github.com/giampaolo/psutil.git;protocol=https"
>
>   S = "${WORKDIR}/git"
>
>   RDEPENDS_${PN} += " \
>     python-subprocess \
>     "
>
> finally, the current (meta-openembedded) meta-python recipe,
> python-psutil_5.0.1.bb, inherits both:
>
>   inherit pypi setuptools
>   require python-psutil.inc
>
> and the corresponding .inc file contains:
>
>   RDEPENDS_${PN} += " \
>     ${PYTHON_PN}-shell \
>     ${PYTHON_PN}-subprocess \
>     ${PYTHON_PN}-threading \
>   "
>
> so the first recipe inherits pypi, the second one inherits setuptools,
> and the third inherits *both*. what is the *preferred* style?
>
>   i'm assuming that if a python module is availably via pypi, then
> you'd go with that; otherwise, just use regular setuptools. and not
> being a python guru, why does that third recipe need to inherit both?
>
>   i did a quick grep of the current meta-python layer to see the
> frequency of each, and got:
>
>   $ grep -r "inherit pypi$" | wc -l
>   13
>   $
>
>   $ grep -r "inherit pypi setuptools" | wc -l
>   157
>   $
>
> so, clearly, far more python recipes inherit both as opposed to just
> inheriting pypi. i don't know enough about python recipes to
> appreciate if this distinction is necessary or not. can someone
> clarify this? thanks.

  grrrrrr ... i just looked more closely and it appears that all of
the "recipe" files under meta-python that inherit only pypi are all
".inc" files, being included by recipe files that first inherit
setuptools. so, again, clarification on the proper way to do this
would be nice.

rday

-- 

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Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
LinkedIn:                               http://ca.linkedin.com/in/rpjday
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