In-progress builds not cancelled upon new source upload

[dobey]

When building a silo, if the source package being built has already been uploaded to the silo PPA, and still has builds in progress, running build again (because a new MP was added for example), does not cancel the existing builds.

To save resources, any existing builds of the relevant source package should be canceled before uploading the new source package to the PPA.

[Robert Bruce Park (robru)]

Surely this is an lp PPA feature? Any PPA behaves the same way when you do two uploads in a row, the new upload doesn't cancel the old one.

[dobey (dobey)]

Yes, in general that is how LP builds, but with CI train it's a more common occurrence I think, and it would be nice if bileto would use the API to cancel existing builds when doing the uploads.

The difference here is that most clients of CI train don't have direct access to the PPA, and so can't cancel builds prior to uploading, but can do so on their own PPAs. Since bileto is the proxy for uploads, it seems like it should handle this responsibility as well. IIRC, it should be fairly easy to do with the API.

[William Grant (wgrant)]

Launchpad shouldn't do this in general. If the CI train desires that behaviour then it can cancel superseded builds itself.

[Colin Watson (cjwatson)]

Yeah, I thought about implementing this in Launchpad at one point, but eventually decided against it because (a) our buildd resources have drastically increased since then, and (b) I can imagine situations where somebody reasonably still wants to see whether the previous version succeeds or fails even though they've uploaded another one. Better to keep the policy somewhere else.