Following the DebConf25 talk by Ian Jackson tag2upload - upload simply by pushing a signed git tag I decided to use the quiet time during the day of the DayTrip on DebConf 25 to try out uploading a package using tag2upload.

Given the current freeze a couple of the packages I maintainer have new releases waiting. I decided on uploading the new version of labwc to experimental. Labwc is a Wayland compositor based on the wlroots compositor library (the library that sway is using). Labwc is inspired by the Openbox window manager. The upstream team of Labwc released version 0.9.0 last week, the first version that is based on wlroots 0.19.x. Wlroots 0.19.x is also only available in experimental, so that was a good fit for trying an upload with tag2upload.

I first used my usual workflow, going into my package repository, doing get fetch origin, checking out the tag of the new release and tagging that with git tag upstream/0.9.0. Then I bumped the version in the debian/experimental branch, adapted the debian/control file for the changed wlroots dependency, committed and built the package using git-buildpackage to check if it builds fine and there are no lintian errors. Then I moved on to look at tag2upload.

As a starting point for using tag2upload I read the blogpost by Jonathan Carter My first tag2upload upload. It pointed me to one very important option of git debpush, namely the --baredebian option which I have to use because I use the bare Debian git layout. Given that the last upload of labwc I did was to unstable, I also had to add the --force=changed-suite.

I also started right away to use the --tag-only option, because for my first tests I only wanted to have local changes and nothing pushed to anywhere. I also used the --dry-run option. This led to the following command:

> git debpush --baredebian --force=changed-suite --dry-run --tag-only
tags 0.9.0, upstream/0.9.0 all exist in this repository
tell me which one you want to make an orig.tar from: git deborig --just-print '--version=0.9.0-1' TAG
git-debpush: git-deborig failed; maybe try git-debpush --upstream=TAG

This was a bit confusing, because the error message talked about git-deborig, but I was using git-debpush. I also did not want to make an orig.tar! The --upstream option in the git-debpush(1) manual gave an explanation for this:

When pushing a non-native package, git-debpush needs a tag for the upstream part of your package.

By default git-debpush asks git-deborig(1), which searches for a suitable tag based on the upstream version in debian/changelog.

So apparently git-debpush can not find out what the correct tag for the upstream version is, because git-deborig can not find out what the correct tag for the upstream version is. git-debpush simply calls git deborig --just-print --version="$version" in line 437. This fails because I initially created a second upstream/0.9.0 to the existing 0.9.0 release tag. I do this for git-buildpackage to find the upstream sources, but with multiple tags git-deborig is not sure which one is the tag it should use (although both point to the same commit).

So I removed the upstream/0.9.0 tag and ran git debpush again and now there was no error message (besides the warning regarding the changed suite) but it also did not give an feedback about what is happening. So I tried without the --dry-run option. Again, no output whatsoever, other than the warning about the changed release, BUT my gnupg asked me for permission to sign via my yubikey! And when I looked at the list of tags, I saw that there is now a debian/0.9.0-1 tag that was not there before! Looking at the tag I saw that it was a tag in the format described in the tag2upload(5) manual page, containing the following lines:

labwc release 0.9.0-1 for experimental

[dgit distro=debian split --quilt=baredebian]
[dgit please-upload source=labwc version=0.9.0-1 upstream-tag=0.9.0 upstream=4beee3851f75b53afc2e8699c594c0cc222115bd]

and the tag was signed by me. The 4beee3851f75b53afc2e8699c594c0cc222115bd commit ID is the commit the 0.9.0 tag points to.

Now that I had a signed commit tag in the correct format, I went to the labwc packaging repository on salsa and enabled the webhook to trigger the tag2upload service (I just saw that the documentation was updated and there is now a global webhook on salsa, so this step is not needed anymore).

Finally I pushed the tags using git push --tags. I could also have used git-debpush for this step, but I’d rather use git directly. I then looked at the tag2upload queue and saw how a worker built and uploaded the newest labwc release and I also got an email from the tag2upload service [tag2upload 275] uploaded labwc 0.9.0-1. And a couple of minutes later I got the confirmation that labwc 0.9.0-1 was accepted into experimental. Great!

So, to conclude: for tag2upload to work we simply need a git tag in the correct format. The tag2upload service now gets triggered by every pushed tag on salsa but only acts on tags that adhere to the tag2upload(5) format. git-debpush is a simply bash script that creates such a tag and by default also pushes the tag.

I think the script could be a bit more verbose, for example telling me that it created a tag and the name of that tag. I think the dependency on git-deborig is also a problem. I use git-buildpackage to build my packages and by default git-buildpacakge assumes upstream tags are of the form upstream/%(version)s (source). I could now change that for all the packages I maintain, but I also think it makes sense to control the tag myself and not use a tag that is controlled by upstream. Upstream could change or delete that tag or I might need to create a tag for a version that is not tagged by upstream.

I also think git-debpush is a rather mileading command name, given that the main task of the script is to create a tag in the correct format.

Other than that, I’m pretty happy about this service. I have a rather crappy uplink at home and it is not so uncommon for my uploads to fail because the connection dropped during dput. Using a simple git based upload approach makes these problems a thing of the past. I might look into other ways to create the needed tag, though.