Undefined behavior when ubuntu/dual silo contains manual source package.

[Robert Bruce Park]

Long story short, the "dual landing" logic only works on MPs. If you have a manual source package configured in your dual silo, what happens is that jenkins doesn't have access to the source package (since it's only in the PPA and not in the silo dir), and thus building fails with a cryptic FileNotFoundError:

https://ci-train.ubuntu.com/job/ubuntu-landing-036-1-build/22/console

2015-06-17 17:13:51,568 ERROR Uncaught exception: FileNotFoundError: [Errno 2] No such file or directory: '/var/lib/jenkins/silos/ubuntu/landing-036/qtmir-gles_+vivid'

At the very least we should probably catch this exception and print a better error message, but even better would probably be to add a check in the prepare job that prevents this situation from even being configured in the first place.

Alternately, the dual landing silo could download the source from the PPA and dual build it for vivid.

[Timo Jyrinki (timo-jyrinki)]

I think catching it during prepare at this point would be proper. I can't think of (m)any situations where the same manual source package version would be uploaded to both releases at the same time. Catching it during prepare would at least let us know if there's a real use case for it.

[Robert Bruce Park (robru)]

Ok, since this bit us again today I decided to revisit it.

I've corrected the bit of logic that was attempting to build secondary builds from nonexistent MPs, and confirmed in staging that it's now "safe" to include manual sources in dual silos. **HOWEVER** if you do this, the watch phase does not actually watch the manual vivid sources, only wily.

I'll have to fix this properly later, so that watch phase watches everything, but at least for now this fix will unblock us and at least make manual sources possible.

[Robert Bruce Park (robru)]

Ok I've fixed the train to now watch manual sources in both wily+vivid correctly.