[Uno 6.0 + UnoLib + WebView] Problem publishing Desktop App on MacOS

[al-kau]

Problem

I have a solution with 2 projects:

• Uno Platform App - Uno6.Desktop.csproj (Uno.Sdk 6.0.130)
• Uno Platform Library - Uno6.WebView.csproj (Uno.Sdk 6.0.130)

Uno6.Desktop.csproj project has a reference to Uno6.WebView.csproj project.
Both projects contain xaml-files with WebView2 so I add the WebView feature to them.

I got an error when publishing a project on MacOS, and by the way, the project is successfully published on Linux and Windows.

Uno6.Desktop net9.0-desktop failed with 1 error(s) (12,1s) → publish/
    /Users/Dev/.nuget/packages/uno.sdk.extras/5.6.3/buildTransitive/Uno.Sdk.Extras.Publish.MacOS.targets(31,3): error MSB4018: 
      The "GenerateAppBundle_vb5ec6eb91d" task failed unexpectedly.
      System.IO.IOException->Microsoft.Build.Framework.BuildException.GenericBuildTransferredException: The file '/Users/Dev/experiments/Uno6.Desktop/publish/Uno6.Desktop.app/Contents/MacOS/WebView2Loader.dll' already exists.
         at Interop.ThrowExceptionForIoErrno(ErrorInfo errorInfo, String path, Boolean isDirError)
         at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String path, OpenFlags flags, Int32 mode, Boolean failForSymlink, Boolean& wasSymlink, Func`4 createOpenException)
         at Microsoft.Win32.SafeHandles.SafeFileHandle.Open(String fullPath, FileMode mode, FileAccess access, FileShare share, FileOptions options, Int64 preallocationSize, UnixFileMode openPermissions, Int64& fileLength, UnixFileMode& filePermissions, Boolean failForS
      ymlink, Boolean& wasSymlink, Func`4 createOpenException)
         at System.IO.FileSystem.CopyFile(String sourceFullPath, String destFullPath, Boolean overwrite)
         at Uno.Sdk.Extras.Tasks.GenerateAppBundle_vb5ec6eb91d.CopyExecutables(List`1 executables, String appPath)
         at Uno.Sdk.Extras.Tasks.GenerateAppBundle_vb5ec6eb91d.Execute()
         at Microsoft.Build.CommandLine.OutOfProcTaskAppDomainWrapperBase.InstantiateAndExecuteTask(IBuildEngine oopTaskHostNode, LoadedType taskType, String taskName, String taskLocation, String taskFile, Int32 taskLine, Int32 taskColumn, IDictionary`2 taskParams)

Question

What is the correct way to add WebView feature in this case?

How to reproduce it

• Prerequisites
  • dotnet
• Open a Terminal.
  • mkdir experiments && cd experiments
  • dotnet tool install -g uno.check
  • ~/.dotnet/tools/uno-check -v --non-interactive --fix --skip xcode --skip androidemulator --skip androidsdk --skip git --skip openjdk
  • dotnet new unoapp -o Uno6.Desktop -preset "recommended" -platforms "desktop" -vscode False -theme "fluent" -presentation "mvvm" -http "none" -di False -log "none" -nav "blank" -toolkit False -theme-service False
  • cd Uno6.Desktop
  • dotnet new unolib --name Uno6.WebView
  • dotnet reference add ./Uno6.WebView/Uno6.WebView.csproj --project ./Uno6.Desktop/Uno6.Desktop.csproj
  • nano ./Uno6.Desktop/Uno6.Desktop.csproj

     <UnoFeatures>
           Mvvm;
           SkiaRenderer;
    +      WebView;
     </UnoFeatures>

  • nano ./Uno6.WebView/Uno6.WebView.csproj

    - <TargetFrameworks>net9.0;net9.0-ios;net9.0-android;net9.0-windows10.0.26100;net9.0-browserwasm;net9.0-desktop</TargetFrameworks>
    + <TargetFrameworks>net9.0;net9.0-desktop</TargetFrameworks>

    - <!--
    - <UnoFeatures></UnoFeatures>
    - -->
    + <UnoFeatures>
    +      WebView;
    + </UnoFeatures>

  • dotnet publish ./Uno6.Desktop/Uno6.Desktop.csproj -o=./publish -c=release -f=net9.0-desktop -r=osx-x64 -p:PackageFormat=app

[spouliot]

@al-kau this looks like #20777

Can you check if you have satellite assemblies in the bin/Release/net9.0-desktop/osx-x64/publish/ directory ?

[al-kau]

I have 6 WebView2Loader.dll files inside the publish directory and one copy of the dll in the Uno6.Desktop.app package

./Uno6.Desktop.app/Contents/MacOS/WebView2Loader.dll
./Uno6.WebView/runtimes/win-arm64/native/WebView2Loader.dll
./Uno6.WebView/runtimes/win-x64/native/WebView2Loader.dll
./Uno6.WebView/runtimes/win-x86/native/WebView2Loader.dll
./runtimes/win-arm64/native/WebView2Loader.dll
./runtimes/win-x64/native/WebView2Loader.dll
./runtimes/win-x86/native/WebView2Loader.dll

List of all items in the publish directory publish-ls.txt

[spouliot]

thanks, this seems a bit different. I'll have a look asap

[spouliot]

It's a different issue.

It does not need Uno6.WebView.csproj to duplicate.

From a clean build the first publish can work. E.g. if I publish for osx-x64 then ./Uno6.WebView/runtimes/win-x64/native/WebView2Loader.dll gets into the publish directory. That's fine since there's a single copy of that (native( library.

If I publish again for osx-arm64 then the win-arm64 version gets added and that fails (since it's a duplicate).

This happens because those are native libraries (for Windows), not assemblies, and should be treated differently (in case of macOS they should be ignored). The fact that the same file extension is used (for Windows) triggers incorrect logic.

[spouliot]

What is the correct way to add WebView feature in this case?

What you did is correct.

A clean, before each macOS publish (x64 and arm64), would be a workaround.

Also (a bit more tricky but) you could edit the <UnoFeatures> not to include WebView for macOS. This is because WebView is built-in into the macOS skia host since it has no external dependencies (it's part of the OS).

I've opened #20782 to track the issue.