Remove PyXML from Fedora
The goal of this Feature is to remove the PyXML package from Fedora.
- Name: toshio
- Email: email@example.com
- Targeted release: Fedora 19
- Last updated: 2013-02-28
- Percentage of completion: 95% (19 out of 20 packages resolved)
PyXML has been dead upstream for many years. The main authors of it have stated this explicitly on the python-dev mailing list. It's successor, the python stdlib's xml module, has been getting bugfixes that PyXML has not. The current Fedora package maintainer (rrakus) asked about removing it in February, 2012.
The Python stdlib in python2.x also has the dubious behaviour of importing PyXML if it is installed and replacing its own code with PyXML's. In some cases, this leads to bugs (For instance: Eric bug, Docutils bug)as the old PyXML code does not cope with some usages that the version in the stdlib does.
We want to remove this package from Fedora. To do that we need to decide what happens to the packages that depend on it. After analyzing the packages that use it, most of them will be ported to another xml library as part of this Feature. However, a few packages will be dropped from Fedora instead.
Benefit to Fedora
Fedora will no longer have to carry old code with known bugs and no upstream maintainance. Packages that depended on that old code will be ported to a more responsive upstream codebase. Use of the python xml module will be more consistent as it will always be implmented with code from the python stdlib rather than code from the stdlib unless PyXML is installed on the user's system.
An F17 repoquery run revealed 20 packages that had deps on PyXML: https://fedoraproject.org/wiki/User:Toshio/Remove_PyXML#Deps I analyzed them and opened up bugs to deal with them in various ways. The open issues are tracked here: https://bugzilla.redhat.com/show_bug.cgi?id=843176
At the moment, Rawhide is down to 1 package with a dep on PyXML.
$ repoquery -q --tree-whatrequires PyXML PyXML-0:0.8.4-28.fc18.x86_64 [cmd line] \_ katello-cli-common-0:1.1.10-1.fc19.noarch [1: PyXML = 0.8.4-28.fc18] | \_ katello-cli-0:1.1.10-1.fc19.noarch [1: katello-cli-common = 1.1.10-1.fc19] | | \_ katello-cli-unit-tests-0:1.1.10-1.fc19.noarch [1: katello-cli = 1.1.10-1.fc19] \_ katello-cli-unit-tests-0:1.1.10-1.fc19.noarch [1: PyXML = 0.8.4-28.fc18]
The plan for that is:
- katello-cli-common: Port to python-dateutil has been applied upstream. New release, 1.3 should contain the fix which is due out in February.
Once that package is dealt with, I'll retire and block the PyXML package in F19/rawhide.
How To Test
- Check that there is no PyXML package in the repositories: On F19,
repoquery -q --whatprovides PyXML=> should return no output.
- Check that nothing requires PyXML in the repositories: On F19,
repoquery -q --whatrequires PyXML=> should return no output.
This Feature should barely be noticable to Fedora end users. People who look at the package set itself instead of simply using the applications inside of it will notice that the packages for PyXML, comoonics, and grc have been removed. If anyone uses comoonics or libopensync-plugin-google-calendar, they will notice that it is no longer in Fedora. Users of grc should already have experienced the switch to gnuradio as the gnuradio package obsoletes grc.
Covered in the scope section.
We'll ship Fedora 19 with some packages still depending on PyXML and a PyXML package still in the repository. This Feature will be retargetted for F20.
- Python programmers who use the xml module may find that a few pieces of it work differently than in the past. This is due to Fedora no longer shipping PyXML. This change allows the python stdlib's xml module to be visible to programmers (PyXML replaced the stdlib's code with its own). This was done because PyXML code is older and buggier than the stdlib code and unmaintained upstream.