CodeSignTask hitting long path error when signing SiteExtension packages with runtime store

I’m trying to sign a SiteExtension nuget package that contains dotnet runtime store

Signing fails with the following error:

 SignToolTask starting.
  DryRun: True
  Signing mode: Real
  MicroBuild signing logs will be in (Signing*.binlog): D:\github\aspnet\AspNetCore\artifacts\logs\
  MicroBuild signing configuration will be in (Round*.proj): D:\github\aspnet\AspNetCore\obj\
C:\Users\pakrymet\.dotnet\buildtools\korebuild\3.0.0-build-20181207.1\modules\KoreBuild.Tasks\CodeSign.targets(51,5): error : The specified path, file name, or both are too long. The fully qualified file name must be less than 260 characters, and the directory name must be less than 248 characters. [C:\Users\p akrymet\.dotnet\buildtools\korebuild\3.0.0-build-20181207.1\KoreBuild.proj]
  SignToolTask execution finished.

After attaching to MSBuild and catching the first change exception I was able to figure out that the path that is being create is D:\github\aspnet\AspNetCore\obj\ContainerSigning\16D285869A01B4C54E3C5CDA81CE0A9B075BD2A43F824EAFB00AFB3B3FC4497F\content/store/x64/netcoreapp3.0/microsoft.aspnetcore.azureappservices.hostingstartup/3.0.0-preview-1999-0010/lib/netcoreapp3.0/Microsoft.AspNetCore.AzureAppServices.HostingStartup.dll

So even if I remove my base directory obj\ContainerSigning\16D285869A01B4C54E3C5CDA81CE0A9B075BD2A43F824EAFB00AFB3B3FC4497F\content/store/x64/netcoreapp3.0/microsoft.aspnetcore.azureappservices.hostingstartup/3.0.0-preview-1999-0010/lib/netcoreapp3.0/Microsoft.AspNetCore.AzureAppServices.HostingStartup.dll is still 270 characters long.

Not sure how to fix or workaround this.

[tmat]

I see. Cool, good to know that we can get rid of any workaround that we implement once we move to 16.0. @JohnTortugo let’s implement a workaround then and file an issue to remove it once we move to msbuild 16.0

[markwilkie]

nevermind, found it: https://github.com/dotnet/arcade/pull/1529