upstream merger hooks do not propagate to downstream jobs' builder_hooks

[Michał Sawicz]

When you change the hooks parameter for a -ci or -autolanding job, that does not propagate to builder_hooks of downstream jobs.

Case at hand:

http://s-jenkins:8080/job/unity-mir-ci/169/console failed because builders could not pick up Mir from daily-build PPA, even though the hook doing that was added to "hooks" in the job.

[Francis Ginther (fginther)]

Unfortunately, this is intentional. This used to work as described but we had to change the behavior due to https://bugs.launchpad.net/cupstream2distro-config/+bug/1168745.

Essentially we wanted to specify different hook configurations for different builds. An example would be to skip the code coverage hook for armhf builds, allowing the build to complete faster. When there was only one parameter for "hooks" all jobs always inherited from the parent job and there was no way to customize the child jobs as needed.

Given this background, is there still a case for this to be a bug? Beyond running an experiment on a specific build, is there a use case I'm missing?

[Michał Sawicz (saviq)]

The use case is transitions that we can't/wont handle otherwise. Case at hand - mir and unity-mir. While it's desirable to only work against distro and mbs within a stack, it's also useful sometimes to test against daily-build PPA I believe.

Shall we just get the builder-hooks param on the upstream -ci and -autolanding jobs?

[Francis Ginther (fginther)]

> Shall we just get the builder-hooks param on the upstream -ci and -autolanding jobs?

Doing that would reintroduce lp:1168745, which I don't want to do. But there may be another way to solve this without introducing the issue. I'll need to do some research on what jenkins allows, but basically I want to:
 - Remove 'builder-hooks' and just use 'hooks' for parent and child jobs.
 - For jobs that need custom configuration hooks, specify the common set as 'hooks', then add the additional hooks as 'custom_hooks'.
 - Pass both $hooks and $custom_hooks to pbuilderjenkins (may need to update pbuilderjenkins to support this).

[Francis Ginther (fginther)]

Actually, this might require a change to https://launchpad.net/jenkins.pbuilder.plugin, which is the jenkins plugin that wraps calls to pbuilderjenkins. Need to investigate.