RPM 4.19: Dynamic subpackages with Python extras
by Miro Hrončok
Hello Python packagers.
RPM 4.19 introduces this feature:
https://rpm-software-management.github.io/rpm/manual/dynamic_specs.html
I decided to write this email to gather my thoughts. I believe that with this,
we can turn manual Python extras subpackages like this:
%package -n python3-...
Summary: %{summary}
%description -n python3-... %_description
%pyproject_extras_subpkg -n python3-xxx extra1 extra2
(See https://docs.fedoraproject.org/en-US/packaging-guidelines/Python/#Extras
for what that means.)
Into something like this:
%package -n python3-...
Summary: %{summary}
%description -n python3-... %_description
...
%install
%pyproject_install
...
%pyproject_generate_extras_subpkgs -n python3-xxx
The %pyproject_generate_extras_subpkgs macro would parse the installed
.dist-info directory to find out what extras are available and generate
subpackages for all of them.
(Obviously, the macro name is open up for discussion.)
----------------
An API would be required to exclude extras:
- that are not useful for other packages
(for example build/development requirements, commonly named dev, doc or test)
- that have requirements that are not packaged in Fedora
For example (mimicking the API of %pyproject_check_import):
%pyproject_generate_extras_subpkgs -n python3-xxx -e test -e 'nonfree*'
----------------
However, extras are also currently manually passed to %pyproject_buildrequires:
%generate_buildrequires
%pyproject_buildrequires -x extra1 -x extra2 -x test
It should already be possible to implement automatic extras discovery in
%pyproject_buildrequires with older RPM versions and allow it to be used this way:
%generate_buildrequires
%pyproject_buildrequires <FLAG_TO_ENABLE_ALL_EXTRAS> -X 'nonfree*'
RPM macros can only accept short flags, so <FLAG_TO_ENABLE_ALL_EXTRAS> can
either be -x '*' (if we start treating -x values as globs, which is backwards
compatible and probably generally useful), or a single-letter switch such as -a
(but honestly we are running out of meaningful letters).
(When -X is used, <FLAG_TO_ENABLE_ALL_EXTRAS> can probably be implied. However,
an explicit form needs to exist for packages that don't need to exclude any
extras at all.)
Eventually, I'd like to make <FLAG_TO_ENABLE_ALL_EXTRAS> the default, once RPM
4.19 is omnipresent.
----------------
Combined, this would mean that the packager needs to:
1. specify extras that are not supposed to be used as BRs
2. specify extras that are not supposed to be packaged
In the ideal word (2) is a superset of (1).
Should %pyproject_generate_extras_subpkgs somehow inherit the -Xes from
%pyproject_buildrequires?
When a package has extra1, extra2, nonfree1, nonfree2 and test extras, one
could do:
%generate_buildrequires
%pyproject_buildrequires <FLAG_TO_ENABLE_ALL_EXTRAS> -X 'nonfree*'
...
%pyproject_install
...
%pyproject_generate_extras_subpkgs -X test
That would mean:
- extra1 is BRed and packaged
- extra2 is BRed and packaged
- test is BRed but not packaged
- nonfree1 is neither
- nonfree2 is neither
----------------
Alternatively the information could be supplied by %globals:
%global _python_ignored_extras nonfree*
%global _python_unpackaged_extras test
However, I somehow dislike this approach.
----------------
I'd appreciate your thoughts on the matter.
--
Miro Hrončok
--
Phone: +420777974800
IRC: mhroncok
4 days, 19 hours
New %{ld_ldflags} macro?
by Dridi Boukelmoune
Greetings,
This weekend I played with the Hare [1] toolchain and ran into an
interesting case. The build system assumes an LDFLAGS variable for
direct invocation, not through GCC or Clang. Ironically, the hare(1)
command will also hide the ld(1) command just like GCC or Clang,
but it doesn't support the -Wl,flag syntax to pass flags to the linker.
So I came up with a macro derived from %{build_ldflags} that I called
%{ld_ldflags} to have a similar naming convention and convey the idea
of direct ld execution:
> %global ld_ldflags %{lua:
> sep=''
> for gcc_flag in string.gmatch(macros.build_ldflags, '%S+') do
> if gcc_flag:match '^\-Wl,' then
> ld_flag=string.gsub(gcc_flag, '\-Wl,', '')
> print(sep..string.gsub(ld_flag, ',', ' '))
> sep=' '
> end
> end}
Please note that I'm not a proficient Lua developer, nor an advanced
RPM macro author, so I took the path of least resistance to reach the
WorksOnMyMachine™ point.
I attached the current work-in-progress spec file where I used this
macro, but you won't be able to test it without a compatible harec
package. I quickly hacked a harec refresh together [2] but I don't
have the bandwidth to maintain that kind of stack. I have yet to
submit my trivial patch upstream, maybe next weekend I will make
more progress on Hare packaging.
I thought it was an interesting case of inadequate LDFLAGS and
that the macro I came up with could help in that regard. I didn't take
the time to see whether other packages were running into the need
for "non GCC" ld flags, so even before someone picks hare up, it
could be useful for existing packages.
Best,
Dridi
[1] https://harelang.org/
[2] https://src.fedoraproject.org/rpms/harec/pull-request/1
1 month
