= Proposed Self Contained Change: Django 2.0 =
* Matthias Runge <Mrunge AT fedoraproject DOT org>
* Miro Hrončok <Churchyard AT fedoraproject DOT org>
* Petr Viktorin <Pviktori AT fedoraproject DOT org>
This change is about upgrading python-django to version 2.0. The
latest Django release drops support for Python 2, but a few Django
apps packaged in Fedora do not yet support Python 3. A compatibility
package will be provided for those.
== Detailed Description ==
The latest Django release 2.0 finally drops support for Python 2.7.
Not all dependent applications in Fedora can keep up with Djangos
pace. This change describes a way how to enable both, keeping 2.7
compatibility and also leveraging the latest version.
The python-django package will be updated to 2.0, Python 2
subpackage(s) will be removed. A new compatibility python2-django1.11
package will be created with Python 2 version of Django 1.11. The
Django 1.11.x series is the last to support Python 2.7, it also has
Long Term Support (supported until April 2020 by upstream). See the
Django 2.0 release notes for details about Django compatibility with
various Python versions.
The new python2-django1.11 package will obsolete python2-django < 2
and python-django < 2, but it will deliberately not provide either of
those. This will render packages depending on python(2)-django FTBFS
(or broken runtime dependencies if they don't require Django at
buildtime). This is intentional. If we don't do that, all Django
packages in Fedora will just keep dragging the Legacy Python
dependency chain forever. Package owners of Django applications
requiring Python 2 will need to manually adjust their dependencies to
use python2-django1.11 or move to Python 3 only (this is preferred but
not always possible). Package owners of Django libraries will need to
coordinate this with package owners of the applications. The rule of
thumb is: If the library is not required by an application (packaged
in Fedora) that uses Legacy Python, remove the Python 2 subpackage (or
retire the package, if it cannot support Python 3).
There will be packages that fail to build or have broken dependencies.
Package owners shall fix those by the steps described above. Proposal
owners will send dist-git Pull Requests or Bugzilla patches to help.
Proven packager powers will be used to merge those after 14 days of no
activity. The removal of leftover packages from Fedora will be
coordinated with FESCo (for approval) and releng (for execution).
Most of the Django packages in Fedora are already Python 3 compatible.
Note that we are aware that naming the compatibility package
python2-django would make this entire change much easier. But we'd
very much like to retire the entire Python 2 based Django ecosystem at
this point already. Creating python2-django1.11 and not providing
python2-django is a compromise. Also, we plan to provide it as a
contingency plan if necessary, see bellow.
== Scope ==
* Proposal owners:
drop Python 2 subpackage(s) from python-django, upgrade python-django
to 2.0 and package python2-django1.11 for Python 2 only.
* Django apps owners:
Either update to Python 3 or use python2-django1.11 as a dependency.
* Django libraries owners:
Either drop Python 2 subpackages (eventually retire the package if no
subpackages are left) or use python2-django1.11 as a dependency for
the python 2 subpackages iff those are needed by apps. When removing
subpackages, add proper Obosletes tags to their Python 3 counterparts.
When orphaning entire packages, add Obosletes to the python3-django
* Release engineering:
releng will help with bulk retirement of packages that fail to keep up
with this proposal
Releng ticket: #7211 https://pagure.io/releng/issue/7211
* Policies and guidelines:
- Python packaging guidelines
- Documentation should be provided
* List of packages requiring python2-django/ python-django without
having django in their name:
Platform & Fedora Program Manager
Red Hat Czech s.r.o., Purkynova 99/71, 612 45 Brno, Czech Republic