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=== Rebuild everything else ===
 
=== Rebuild everything else ===
  
Now this gets a bit magical but what I did is that I've used [https://github.com/hroncok/mini-mass-rebuild mini-mass-rebuild] to rebuild everything. Remember to bump the release and use the side tag (the fedpkg-build.sh script needs to adjusted).
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Now this gets a bit magical but what I did is that I've used [https://github.com/hroncok/mini-mass-rebuild mini-mass-rebuild] to rebuild everything. Remember to bump the release and use the side tag (the fedpkg-build.sh script needs to be adjusted).
  
 
What is everything? First, i get the packages that buildrequire {{package|python3-devel}}:
 
What is everything? First, i get the packages that buildrequire {{package|python3-devel}}:

Revision as of 11:31, 9 July 2018

Upgrading Python from 3.N-1 to 3.N

Here are the notes from upgrading Python form 3.6 to 3.7. They are created to save us time next time when upgrading to 3.8. It is not a comprehensive guide, but if it once get to it, it'd be great.

Create a Change Proposal

Before anything can happen, we need to create a Change Proposal. Follow the normal procedure, get inspired by previous changes, but make sure the process haven't changed (copypasta is good, but check if the template hasn't been updated).

Create python3N package

This can happen as soon as the first alpha is released. If you have enough resources, try to do it even before. The python3X packages are designed to have flat/nonflat switches since Package-x-generic-16.pngpython36, so you will use this package once you want to update Package-x-generic-16.pngpython3.

Make a copr repo, bootstrap "important stuff" in it

Bootstrapping Python packages is nontrivial. Chances are high that form the upgrade to 3.N-1, the bootstrap sequence has changed, as more packages switched to python3-sphinx etc. Start as early as possible.

For 3.7, I've used rpm-list-builder. The yaml recipe is archived on my GitHub. It has some comments. Note that rpm-list-builder has limitations:

  • it doesn't bump releases, so you need to do that manually if you build one package once and the new build has new functionality (aka not just for tests)
  • the "continue form here" future isn't very useful for us and was designed for different purpose, so what i did is that most of the yaml was commented out and I was uncommenting sections that i needed keeping finished stuff above, TODO stuff at the botttom
  • everything is sequential. go do something different form time to time

When Package-x-generic-16.pnggdb is updated in Fedora, you need to delete all Package-x-generic-16.pngpython3 builds from the copr repo, and bootsrap Package-x-generic-16.pnggdb - Package-x-generic-16.pngpython3 - Package-x-generic-16.pnggdb once more.

What wasn't done for 3.7 but might have been a good idea is to restart the procedure once in a while. Packages early in the bootstrap sequence were build once with alphas and never tested with betas and rc. I suggest to restart the procedure on beta1 and on rc1.

Preserving the yaml recipe is good, you can use it for Fedora later.

This is the command I've used:

rm work-directory/* -rf && rpmlb --download local --source-directory source-directory python37.yaml python37 --work-directory work-directory --build copr --copr-repo @python/python3.7

I had local fedpkg clones, so I could create quick hotfixes in them. Also a must for Package-x-generic-16.pngpython3 package - you have it updated to 3.N, but rawhide still has 3.N-1.

Once ready, move into Fedora proper

Ready can differ. For 3.7 it was when rc1 was released and all important stuff from the yaml recipe was built in copr (in fact, couple of packages were not, but the fix was known).

Request a side tag

Example: Side tag for Python 3.7 releng issue

You'll get a side tag name (target). It can differ. For 3.7 it was f29-python.

To build in the side tag, you do:

fedpkg build --target=<name>

To wait for builds to get into the repos, do:

koji wait-repo <name> --build=<nvr>

Reproduce the bootstrap sequence

Juts get the recipe and rebuild in the side tag. rpm-list-builder could not do it with 3.7 so I've used a dirty script. Be prepared for failures, packages got updated in the meantime and new deps were added. Tough life.

Rebuild everything else

Now this gets a bit magical but what I did is that I've used mini-mass-rebuild to rebuild everything. Remember to bump the release and use the side tag (the fedpkg-build.sh script needs to be adjusted).

What is everything? First, i get the packages that buildrequire Package-x-generic-16.pngpython3-devel:

 dnf repoquery  --disablerepo='*' --enablerepo='rawhide-source' --whatrequires python3-devel

But I forgot the virtual provides:

dnf repoquery  --disablerepo='*' --enablerepo='rawhide' --provides python3-devel

Also a good idea what actually needs a rebuild is:

dnf repoquery --whatrequires 'libpython3.6m.so.1.0()(64bit)' --source
dnf repoquery --whatrequires 'python(abi) == 3.6' --source

Use 3.N-1 instead of 3.6.

A helpful pkgname command to pipe those things into:

#!/usr/bin/python3
import fileinput


for line in fileinput.input():
    print('-'.join(line.split('-')[:-2]))

Remember that you already built stuff that doesn't need extra rebuild. To remove list of packages form list of packages, I use remove_closed.py:

python3 remove_closed.py all_rawhide already_built remains

There are also build-status.sh and build-failure-reason.sh in mini-mass-rebuild.

parallel -j 32 bash ../build-status.sh -- $(cat ../remains) | tee ../status
for i in free open closed failed canceled; do echo -e $i\\t$(grep " $i" ../status | wc -l); done
cat ../status | grep " closed" | cut -d" " -f1 | tee ../closed
python3 ../remove_closed.py ../remains ../closed ../remains

And:

parallel -j 32 bash ../build-failure-reason.sh -- $(cat ../remains) | tee ../reason
cat ../reason | grep ' build'  # FTBFS
 cat ../reason | grep ' root'   # missing dependency

It's a good idea to mass rebuild everything that remains until the number of closed (built) packages stops at 0. Don't forget not to bump the release over and over again. Later, start investigating the build failure reasons. Untangle any circular deps if found. Add them to yaml recipe for next time. File bugs (block the tracking bug, create an alias (PYTHON3N)). E-mail maintainers. Cry.

Request a side tag merge

Once you feel things look good (ask QA to confirm) and the number of FTBFS is reasonably low (for 3.7 it was 300 (half waiting for deps)), ask releng to merge the side tag. Do this at least a week before the mass rebuild. Releng will most likely not respond within a day, so better plan a future date (a ~week in advance would work best). E-mail devel-announce.

It was not yet possible during 3.7, but check with nirik if creating a test compose from side tag is possible, it could prevent issues like this one (anaconda tracebacks, no compose). Without a proper compose, the rawhide repos are not updated.

When the side tag is being merged, be available. After the merge, stuff thet has higher nevr in rawhide will "win" over the side tag. Double check if Package-x-generic-16.pnggdb has higher nevr in the side tag and bump-rebuild in there if not. Otherwise the buildroot will be broken (Package-x-generic-16.pnggdb will require python(abi) == 3.N-1, but that won't be available). Also, everything that was bootstrapped (not everything from the recipe, but where actual bootstrapping was involved) - rebuild it in the side tag of it has higher nevr in rawhide, or you will need to bootstrap it again after the merge.

Once merged, releng will give you list of packages that had higher nevr in rawhide. Bump-rebuild them in rawhide once you can koji-wait for python3-3.N.0... build.

After a side tag merge

If there are still FTBFSes (they are), e-mail the maintainers again.

Monitor the state. get the initial list of broken deps:

$ (dnf repoquery --disablerepo='*' --enablerepo='koji' --whatrequires 'libpython3.6m.so.1.0()(64bit)' --source && dnf repoquery --disablerepo='*' --enablerepo='koji' --whatrequires 'python(abi) == 3.6' --source) | pkgname | sort | uniq > rawhide

Diff and update it regularly:

dnf clean all && (dnf repoquery  --disablerepo='*' --enablerepo='koji' --whatrequires 'libpython3.6m.so.1.0()(64bit)' --source && dnf repoquery  --disablerepo='*' --enablerepo='koji' --whatrequires 'python(abi) == 3.6' --source) | pkgname | sort | uniq | diff -u rawhide -

When packages are fixed, check dependent packages. Rebuild those (they might get unblocked).

After the compose is built

The packages are in rawhide repos, yay! Mass rebuild will happen soon, bugs will be open automatically, your job is almost done here.

Keep monitoring stuff. Also monitor devel mialing list for questions.

Rebuild everything in (the 3rd party repo that shall not be named), you can use mini-mass-rebuild with little tweaks. If you are a provenpackager in Fedora, you have the rights here as well, but if you never built anything in there, you need to ask. No nonfree stuff needed rebuilding during 3.7, only free (that might change in the future).

Also, create pythonN-1 package

This needs a new package review request. Ask releng to unretire it. If you will create a nice git merge commit and a PR, note that releng will push a revert commit to the retired repo, so do it afterwards to save yourself doing it twice.