[pkg-uWSGI-devel] Bug#865224: uwsgi: ftbfs with multiple supported python3 versions

[Scott Kitterman]

On July 17, 2017 7:19:55 PM EDT, gregor herrmann <gregoa at debian.org> wrote:
>On Thu, 13 Jul 2017 18:56:52 -0400, Scott Kitterman wrote:
>
>> > It looks like a cdbs issue to me,
>> >   $(call cdbs_expand_pythonruntime,,python3.6)
>> > breaks while
>> >   $(call cdbs_expand_pythonruntime,,python3.5)
>> > works (and results in "python3" as expected.)
>> > 
>> > A workaround that seems to help is putting
>> >  X-Python3-Version: 3.5
>> > in the Source paragraph of debian/control to prevent it from trying
>3.6
>> > at all. This makes the build work for me (but doesn't help the
>python3.6
>> > transition of course.)
>> > 
>> > This is the worst blocker for the Perl 5.26 transition too (uwsgi
>needs
>> > to be rebuilt because uwsgi-plugin-psgi links against libperl), so
>even
>> > a temporary ugly workaround would be appreciated from this side :)
>> 
>> Changing the python3-all-dev build-depends to python3-dev would
>accomplish the 
>> same thing while allowing a binNMU to work when we make python3.6
>default.  
>> Since this is blocking your work, I would recommend you NMU with that
>change 
>> (I have forgotten approximately everything I ever new about CDBS, so
>I don't 
>> mess with CDBS packages if I can possibly avoid it - I don't plan to
>do this 
>> NMU).
>
>I'm afraid this doesn't help. With the change in Build-Depends from
>python3-all-dev to python3-dev, the build still ends with:
>
>*** asyncio_python27 plugin built and available in
>./asyncio_python27_plugin.so ***
>touch debian/stamp-uwsgi-plugin-asyncio-python
>debian/rules:452: *** no python implementation resolved from flavor
>"python3.6" among packages python-uwsgidecorators
>python3-uwsgidecorators.  Stop.
>dpkg-buildpackage: error: debian/rules build gave error exit status 2
>
>The build log doesn't show anything about python3.6 packages.
>
>From the log:
>
>set -e; \
>sed -e 's/@@pkg_name@@/uwsgi-plugin-python3/g' -e
>'s/@@plugin_name@@/python3/g' -e 's/@@plugin_stem@@/python/g' -e
>'s/@@plugin_alternatives_name@@/uwsgi-plugin-python3/g' -e
>'s/@@plugin_alternatives_stem@@/python3/g' -e
>'s/@@plugin_alternatives_priority@@/35/g' -e
>'s/@@plugin_lang_kind@@/python3/g' -e
>'s/@@plugin_flavors_dotless@@/python36 python35/g' -e
>'s/@@plugin_defaultflavor_dotless@@/python35/g' <
>debian/uwsgi-plugin-__PLUGIN__.rtupdate.in.pri-py >
>debian/uwsgi-plugin-python3.rtupdate;   sed -e
>'s/@@pkg_name@@/uwsgi-plugin-python3/g' -e
>'s/@@plugin_name@@/python3/g' -e 's/@@plugin_stem@@/python/g' -e
>'s/@@plugin_alternatives_name@@/uwsgi-plugin-python3/g' -e
>'s/@@plugin_alternatives_stem@@/python3/g' -e
>'s/@@plugin_alternatives_priority@@/35/g' -e
>'s/@@plugin_lang_kind@@/python3/g' -e
>'s/@@plugin_flavors_dotless@@/python36 python35/g' -e
>'s/@@plugin_defaultflavor_dotless@@/python35/g' <
>debian/uwsgi-plugin-__PLUGIN__.dirs.in.python >
>debian/uwsgi-plugin-python3.dirs;     sed -e
>'s/@@pkg_name@@/uwsgi-plugin-python3/g' -e
>'s/@@plugin_name@@/python3/g' -e 's/@@plugin_stem@@/python/g' -e
>'s/@@plugin_alternatives_name@@/uwsgi-plugin-python3/g' -e
>'s/@@plugin_alternatives_stem@@/python3/g' -e
>'s/@@plugin_alternatives_priority@@/35/g' -e
>'s/@@plugin_lang_kind@@/python3/g' -e
>'s/@@plugin_flavors_dotless@@/python36 python35/g' -e
>'s/@@plugin_defaultflavor_dotless@@/python35/g' <
>debian/uwsgi-plugin-__PLUGIN__.prerm.in.pri-py >
>debian/uwsgi-plugin-python3.prerm;   sed -e
>'s/@@pkg_name@@/uwsgi-plugin-python3/g' -e
>'s/@@plugin_name@@/python3/g' -e 's/@@plugin_stem@@/python/g' -e
>'s/@@plugin_alternatives_name@@/uwsgi-plugin-python3/g' -e
>'s/@@plugin_alternatives_stem@@/python3/g' -e
>'s/@@plugin_alternatives_priority@@/35/g' -e
>'s/@@plugin_lang_kind@@/python3/g' -e
>'s/@@plugin_flavors_dotless@@/python36 python35/g' -e
>'s/@@plugin_defaultflavor_dotless@@/python35/g' <
>debian/uwsgi-plugin-__PLUGIN__.postinst.in.pri-py >
>debian/uwsgi-plugin-python3.postinst;    sed -e
>"s/@@plugin_name@@/python36/g" <
>debian/uwsgi-plugin-__PLUGIN__.install.in >>
>debian/uwsgi-plugin-python3.install; sed -e
>"s/@@plugin_name@@/python36/g" <
>debian/uwsgi-plugin-__PLUGIN__.links.in >>
>debian/uwsgi-plugin-python3.links; sed -e
>"s/@@plugin_name@@/python36/g" <
>debian/uwsgi-plugin-__PLUGIN__.manpages.in >>
>debian/uwsgi-plugin-python3.manpages;  sed -e
>"s/@@plugin_name@@/python35/g" <
>debian/uwsgi-plugin-__PLUGIN__.install.in >>
>debian/uwsgi-plugin-python3.install; sed -e
>"s/@@plugin_name@@/python35/g" <
>debian/uwsgi-plugin-__PLUGIN__.links.in >>
>debian/uwsgi-plugin-python3.links; sed -e
>"s/@@plugin_name@@/python35/g" <
>debian/uwsgi-plugin-__PLUGIN__.manpages.in >>
>debian/uwsgi-plugin-python3.manpages; chmod 755
>debian/uwsgi-plugin-python3.rtupdate; echo
>"debian/uwsgi-plugin-python3.rtupdate usr/share/python3/runtime.d" >>
>debian/uwsgi-plugin-python3.install
>touch debian/expand-files/uwsgi-plugin-python3
>
>(Note the "python36" parts.)
>
>
>Looking through the not ultra-short debian/rules, it seems that
>$(plugin_flavors) still contains something python3.6ish, and then we
>are at the expansion that Niko already found:
>
>        $(if $(filter python,$(plugin_lang)),\
>                $(foreach flavor,$(plugin_flavors),\
>            $(UWSGI_ENV) $(call cdbs_expand_pythonruntime,,$(flavor)) \
>                                $(UWSGI_BUILDER) \
>                                --plugin plugins/$(plugin_src) \
>                                debian/buildconf/uwsgi-plugin.ini \
>                       $(plugin_flavor_prefix)$(subst .,,$(flavor));),\
>         $(UWSGI_ENV) $(cdbs_python2_defaultruntime) $(UWSGI_BUILDER) \
>                        --plugin plugins/$(plugin_src) \
>                        debian/buildconf/uwsgi-plugin.ini \
>                        $(plugin_name))
>
>
>So, both with python3-dev (i.e. no python3.6 around) and with
>python3-all-dev (with python3.6 installed), '$(call
>cdbs_expand_pythonruntime,,python3.6)' fails. Hm.
>
>If someone is into makefile magic:
>
># runtime to use
># resolve from implicit singleflavor or optional binary package or
>optional (favored) flavor
>#  1. provided binary package arch-indep: cdbs_$python_defaultruntime
>#  2. default flavor: cdbs_$python_defaultruntime
>#  3. name of flavor
>cdbs_expand_pythonruntime = $(or $(strip \
>    $(if $(filter $1,$(cdbs_python_indep_packages)),\
>      $(cdbs_$(call _cdbs_expand_python,$1)_defaultruntime))),$(strip \
>    $(foreach f,$(or $(strip \
>     $2),$(strip \
>     $(if $1,$(call _cdbs_expand_pythonflavors,$1))),$(strip \
>     $(if word 2,$(cdbs_flavors),\
>      $(error Too many flavors: $(cdbs_flavors)),\
>      $(cdbs_flavors)))),\
> $(foreach p,$(call _cdbs_expand_pythonflavor2python,$f),$(or $(strip \
>            $(if $(filter $f,$(cdbs_$p_defaultflavor)),\
>                $(cdbs_$p_defaultruntime))),$(strip \
>            $f),\
>            $(error no python runtime resolved \
>                from binary package "$1" and flavor "$2"))))))
>
>
>(from /usr/share/cdbs/1/class/python-vars.mk)
>
>
>So it looks like the cdbs python module finds a python3.6 "flavor"
>(from py3versions) but no runtime for it.
>
>
>Ultimately, this looks like a cdbs problem to me. Maybe we can find a
>bandaid for uwsgi for now to tell d/rules to use only one python3
>flavour or to not bail out of the python3.6 runtime is not detected.

In that case, your X-Python3-Version hack is probably the best way to get the Perl transition done.  It'll be another RC bug against UWSGI once python3.6 is default, but I don't expect that soon.

Scott K