naming-scheme.rst

New Python package naming scheme

Note

This section is related to the renaming of Python binary RPM packages to avoid using the python- prefix without a version. Changing the main package/SRPM name is not required.

Why is this important?

When the time comes and python means Python 3 in Fedora, installing a python-<srcname> package will imply a Python 3 version of this package. This is planned for 2020, when upstream support for Python 2 ends. To achieve this, all Python binary RPM packages have to follow the new naming scheme and use the %python_provide macro, devised to make the switch easier. However, we are still far away from achieving this goal.

Using the outdated naming scheme in your subpackage names or run-time/build-time requirements might cause a range of issues when the switch happens.

What needs to be changed?

Check the names of binary RPM packages you are building from your SRPM, and if you use one of the following naming schemes, you'll find instructions on how to fix it in the section below.

Common naming scheme violations

See the following naming schemes which violate the current naming guidelines:

SRPM	Binary RPMs built	Violation
python-<srcname>	python-<srcname>	unversioned python- prefix in the binary package
python-<srcname>	python-<srcname> python3-<srcname>	unversioned python- prefix in the binary package
<srcname>	<srcname> python3-<srcname>	missing python2- prefix in the binary package

Required changes

Add a %package section for the Python 2 subpackage

To rename the binary RPM package to python2-<srcname>, you should build it as a subpackage with an appropriate name. Make sure to move all related runtime requirements from the main package to the new subpackage and use the %python_provide macro, which will provide both python-<srcname> and python2-<srcname> until the switch to Python 3 happens.

The change should look like this:

.. literalinclude:: specs/module.spec
   :diff: specs/module.spec.orig
   :lines: 15-19,21-32,43

Note, that in case of the last naming scheme example in the table above, when you rename the binary RPM from <srcname> to python2-<srcname>, the %python_provide macro will not provide the old name <srcname>. To keep the upgrade path clean you will have to provide it and obsolete the old verision manually. You may place the tags right after the %python_provide macro:

%{?python_provide:%python_provide python2-%{srcname}}
Provides:   %{srcname} = %{version}-%{release}
Obsoletes:  %{srcname} < current_version-current_release

In the Obsoletes tag, current_version and current_release are the first version and release when the new naming scheme was used.

Use the %python_provide macro in the Python 3 subpackage

Check your Python 3 subpackage (if you build any), and make sure you are using the %python_provide macro to handle provides:

.. literalinclude:: specs/module.spec
   :language: spec
   :emphasize-lines: 5
   :lines: 30-37

Rename the %files section

To assign the %files section to the Python 2 subpackage, add the subpackage name with the versioned prefix after the %files macro. Make sure to use the new versioned macros %{python2_sitelib}, %{python2_sitearch}, and %{python2_version} as well:

.. literalinclude:: specs/module.spec
   :diff: specs/module.spec.orig
   :lines: 67-68,70-74

At this point you should be done. Don't forget to bump the release tag and add a changelog entry indicating you've updated the package to use the new naming scheme.