Triggering Debian Builds on OBS

This is my fifth post of my Google Summer of Code 2018 series. Links for the previous posts can be found below:

• Post 1: My Google Summer of Code 2018 project
• Post 2: Setting up a local OBS development environment
• Post 3: Running OBS Workers and OBS staging instance
• Post 4: Notes on the OBS Documentation

My GSoC contributions can be seen at the following links

• https://github.com/athos-ribeiro/salt-obs
• https://github.com/openSUSE/obs-docu/commits?author=athos-ribeiro

Debian builds on OBS

OBS supports building Debian packages. To do so, one must properly configure a project so OBS knows it is building a .deb package and to have the packages needed to handle and build debian packages installed.

openSUSE’s OBS instance has repositories for Debian 8, Debian 9, and Debian testing.

We will use base Debian projects in our OBS instance as Download on Demand projects and use subprojects to achieve our final goal (build packages agains Clang). By using the same configurations as the ones in the openSUSE public projects, we could perform builds in Debian 8 and Debian 9 in our local OBS deploys. However, builds for Debian Testing and Unstable were failing.

With further investigation, we realized the OBS version packaged in Debian cannot decompress control.tar.xz files in .deb packages, which is the default compression format for the control tarball since dpkg-1.19 (it used to be control.tar.gz before that). This issue was reported on the OBS repositories and was fixed on a Pull Request that is not included in the current Debian OBS version yet. For now, we apply this patch in our OBS instance on our salt states.

After applying the patch, the builds on Debian 8 and 9 are still finishing with success, but builds against Debian Testing and Unstable are getting stuck in a blocked state: dependencies are being downloaded, the OBS scheduler stalls for a while, the downloaded packages get cleaned up, and then the dependencies are downloaded again. OBS backend enters in a loop doing the described procedure and never assigns a build to a worker. No logs with hints leading to a possible issue are issued, giving us no clue of the current problem.

Although I am inclined to believe we have a problem with our dependencies list, I am still debugging this issue during this week and will bring more news on my next post.

Refactoring project configuration files

Reshabh opened a Pull Request in our salt repository with the OBS configuration files for Ubuntu, also based on the openSUSE’s OBS public configurations. Based on Sylvestre comments, I have been refactoring the Debian configuration files based on the OBS docuemtation. One of the proposed improvements is to use debootstrap to mount the builder chroot. This will allow us to reduce the number of dependencies listed in the projects configuration files. The issue which generated debootstrap support in OBS is available at https://github.com/openSUSE/obs-build/issues/111 and may lead to more interesting resources on the matter.

Next steps (A TODO list to keep on the radar)

• Fix OBS builds on Debian Testing and Unstable
• Write patches for the OBS worker issue described in post 3
• Change the default builder to perform builds with clang
• Trigger new builds by using the dak/mailing lists messages
• Verify the rake-tasks.sh script idempotency and propose patch to opencollab repository
• Separate salt recipes for workers and server (locally)
• Properly set hostnames (locally)