On 04. 04. 23 19:24, Dan Čermák wrote:

Hi Miro,

On March 31, 2023 10:06:14 AM UTC, "Miro Hrončok" mhroncok@redhat.com wrote:

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On 30. 03. 23 23:55, Miro Hrončok wrote:

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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.

One challenge: When an extra is removed upstream, the packager might not notice that it needs to be provided/obsole>

That is indeed a problem. What if we made the macro require the list of subpackages (e.g. as a comma separated string) as an argument? The if the packager wouldn't notice the removal, they'd get a build error.

We already have that today without dynamic subpackages, because when you know the list ahead, you can "generate" subpackages already.

$ rpm --eval '%pyproject_extras_subpkg -n python3-... extra1 extra2' %package -n python3-...+extra1 Summary: Metapackage for python3-...: extra1 extras Requires: python3-... = %{version}-%{release} %description -n python3-...+extra1 This is a metapackage bringing in extra1 extras requires for python3-.... It makes sure the dependencies are installed.

%files -n python3-...+extra1 -f .../BUILD/%{name}-%{version}-%{release}.x86_64-pyproject-ghost-distinfo

%package -n python3-...+extra2 Summary: Metapackage for python3-...: extra2 extras Requires: python3-... = %{version}-%{release} %description -n python3-...+extra2 This is a metapackage bringing in extra2 extras requires for python3-.... It makes sure the dependencies are installed.

%files -n python3-...+extra2 -f .../%{name}-%{version}-%{release}.x86_64-pyproject-ghost-distinfo