Timing issue in SDK build when building with source-build

[dseefeld]

When building SDK in source-build on a slower machine, we encountered a timing issue which caused the WebSDK folders to be missing. Looking at the binlog, it appears that the PublishNetSdks target gets called, but the content for these folders has not been produced yet. The issue can be simulated by putting a wait in one of the WebSDK projects:

  <Target Name="DelayToSimulateAsync"
          BeforeTargets="CopyAdditionalFilesToLayout">
    <Exec Command="sleep 150" />
  </Target>

This will cause some of the SDK content to be missing. To work around this in source-build, we added a temporary patch to force PublishNetSdks to wait:

<Target Name="PublishNetSdks"
          BeforeTargets="Build">
+    <ItemGroup>
+      <WebSdkProjectFile Include="$(RepoRoot)src\WebSdk\**\*.csproj" />
+    </ItemGroup>
 
+    <MSBuild Projects="@(WebSdkProjectFile)" />

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