How do I select the Python version when building a RPM from a .spec file on Fedora 35?
The CentOS/RHEL documentation says
Configure the particular Python 3 version in the BuildRequires of the SPEC file to
python36-rpm-macros,python38-rpm-macros, orpython39-rpm-macros.
Fedora only has a python3.9 package and python3-rpm-macros package.
How can I set the Python version? How can I make this selection portable between Fedora, RHEL, and other Enterprise Linux flavors?
%define __python3 /usr/bin/python3.9
%{?fedora:BuildRequires: python3.9}
%{?rhel:BuildRequires: python39-devel}
Is this correct?
%global python_minimum_version 3.9.0
%{?fedora:Requires: python3 >= %{python_minimum_version}}
%{?rhel:Requires: python39 >= %{python_minimum_version}}
%{?fedora:BuildRequires: python3-devel >= %{python_minimum_version}}
# yes, I do crazy things in the rpm build, and I need pip
%{?fedora:BuildRequires: python3-pip}
# without wheel the installed files lack `python_qpid_proton-0.37.0.dist-info`
%{?fedora:BuildRequires: python3-wheel}
%{?rhel:BuildRequires: python39-devel >= %{python_minimum_version}}
%{?rhel:BuildRequires: python39-pip}
%{?rhel:BuildRequires: python39-wheel}
%{?rhel:BuildRequires: python39-rpm-macros}
This seems to produce a package that behaves well on both Fedora and CentOS Stream 8.
On Fedora, latest Python is used, and on CentOS I get Python 3.9 and the #! lines in script get rewritten to use that Python 3.9 automatically.
I consider this a success.