Got a call for help from a colleague who couldn’t get an Acceptance release out of the door. Problem was that the automated build responsible for packaging and deploying the Acceptance version failed. He asked me to take a look…
Inside the build logs we noticed the following error message:
2018-11-13T06:35:22.4133574Z (CoreCompile target) ->
2018-11-13T06:35:22.4133574Z CSC : error CS0006: Metadata file 'D:\b\4\agent\_work\_temp\.sonarqube\resources\1\Google.Protobuf.dll' could not be found [D:\b\4\agent\_work\40\s\MTIL.Domain\MTIL.Domain.csproj]
2018-11-13T06:35:22.4133574Z CSC : error CS0006: Metadata file 'D:\b\4\agent\_work\_temp\.sonarqube\resources\1\SonarAnalyzer.CSharp.dll' could not be found [D:\b\4\agent\_work\40\s\MTIL.Domain\MTIL.Domain.csproj]
2018-11-13T06:35:22.4133574Z CSC : error CS0006: Metadata file 'D:\b\4\agent\_work\_temp\.sonarqube\resources\1\SonarAnalyzer.dll' could not be found [D:\b\4\agent\_work\40\s\MTIL.Domain\MTIL.Domain.csproj]
2018-11-13T06:35:22.4143340Z
This would make you think that there is something wrong with our SonarQube tasks. Would we an obvious reason right? The strange thing is that we weren’t using SonarQube on our Acceptance release build, so why did the build agent mentions something about SonarQube?
Chapter 1 - The story of the canceled build
After further investigation, I noticed that the problem started happening when another build was canceled. This build was using the same repository(but a different branch) to build our development release. And in this build we were using the SonarQube tasks. So maybe something wasn’t cleaned up correctly?
I killed the VBCSCompiler process (it was blocking some files in the _temp folder) and removed the _temp folder completely. This first seemed to work but after doing one build the problem reappeared.
Chapter 2 - The story of the other running build
So the story continues. I started to monitor the build server for other activities and noticed that the problem reappeared when a development build was running that was using the SonarQube tasks. When I tried to do an Acceptance build after the Development build completed, it succeeded without errors.
Our conclusion was that when another build was running on the same repo that was using the SonarQube tasks, it created some conflict that made the other build fail. Sounds like a bug to me?
As a workaround, we temporarily disable the Development build when we try to create an Acceptance build.