TFM exploration

Below is an exploration of different project combinations to asses what it takes to add the net8.0-browser TFM and exercising the most common operations (restore, build, pack, publish)

• For testing I have only tried making the test project net8.0-browser1.0, referencing a net8.0-browswer1.0 class library and calling dotnet test.

General steps to enable the TFM

• Specify the platform with a version (net8.0-browswer1.0)
• Add the property <TargetPlatformSupported>true</TargetPlatformSupported> to a property group.
• Add the version to the list of supported target platform versions:

  <ItemGroup Condition="'$([MSBuild]::GetTargetPlatformIdentifier($(TargetFramework)))' == 'browser'">
    <SdkSupportedTargetPlatformVersion Include="1.0" />
  </ItemGroup>

Findings

• Was not able to just specify net8.0-browser
• Was not able to get rid of warning CA1418: Version '1.0' is not valid for platform 'browser'. Do not use versions for this platform.
  • I suspect this is a matter of "finding" the right "knob" on the SDK.

Unexplored areas

• All the investigation was command-line driven, haven't played through VS yet.

Potential improvements to the experience

• Requirement to specify the target framework during publish when multitargeting:
  • It would be great if we could select a "preferred" target framework for publish.
  • Even better if this is respected by the VS UI.
• Nuget package installation:
  • Select the target framework when installing a dependency (CLI and UI) and have nuget place it in the right itemgroup (or per platform .targets file).

List of scenarios with their description

01 - Standalone app

flowchart TD
subgraph Application
net8.0-browser1.0
end

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02 - Standalone class library

flowchart TD
subgraph Library
net8.0-browser1.0
end

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03 - Standalone multitargeting app

flowchart TD
subgraph Application
net8.0;net8.0-browser1.0
end

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04 - Standalone multitargeting library

flowchart TD
subgraph Library
net8.0;net8.0-browser1.0
end

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05 - Singletargeting app references singletargeting library

flowchart TD

subgraph Application
  net8browserapp["net8.0-browser1.0"]
end

subgraph Library
  net8.0-browser1.0lib["net8.0-browser1.0"]
end

Application-->Library

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06 - Singletargeting app references singletargeting browser library

flowchart TD

subgraph Application
  net8app["net8.0"]
end

subgraph Library
  net8.0-browser1.0lib["net8.0-browser1.0"]
end

Application-->Library

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07 - Singletargeting browser app references singletargeting library

flowchart TD

subgraph Application
  net8.0-browser1.0app["net8.0-browser1.0"]
end

subgraph Library
  net8.0lib["net8.0"]
end

Application-->Library

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08 - Multitargeting app references multitargeting library

flowchart TD

subgraph Application
  net8app["net8.0"]
  net8browserapp["net8.0-browser1.0"]
end

subgraph Library
  net8.0lib["net8.0"]
  net8.0-browser1.0lib["net8.0-browser1.0"]
end

Application-->Library

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09 - Multitargeting app references single targeting library

flowchart TD

subgraph Application
  net8app["net8.0"]
  net8browserapp["net8.0-browser1.0"]
end

subgraph Library
  net8.0lib["net8.0"]
end

Application-->Library

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10 - Multitargeting app references single targeting library (browser)

flowchart TD

subgraph Application
  net8app["net8.0"]
  net8browserapp["net8.0-browser1.0"]
end

subgraph Library
  net8.0browserlib["net8.0-browser1.0"]
end

Application-->Library

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11 - Single targeting app references multi targeting library

flowchart TD

subgraph Application
  net8app["net8.0"]
end

subgraph Library
  net8lib["net8.0"]
  net8.0browserlib["net8.0-browser1.0"]
end

Application-->Library

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12 - Single targeting app references multi targeting library (browser)

flowchart TD

subgraph Application
  net8-browserapp["net8.0-browser1.0"]
end

subgraph Library
  net8lib["net8.0"]
  net8.0browserlib["net8.0-browser1.0"]
end

Application-->Library

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Interesting scenarios

These are scenarios where I had to add additional attributes to the ProjectReference to get things working.

Scenario 10

06 - Single target app references single targeting library (browser)

The app targets net8.0 and the library targets net8.0-browser

flowchart TD

subgraph Application
  net8app["net8.0"]
end

subgraph Library
  net8.0-browser1.0lib["net8.0-browser1.0"]
end

Application-->Library

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• Was able to make the project reference work by adding a couple of properties to it:

  <ProjectReference 
    Include="..\singletargetclasslib\singletargetclasslib.csproj"
    SkipGetTargetFrameworkProperties="true" 
    ReferenceOutputAssembly="false" />

• This effectively disabled referencing the output assembly but maintained the reference, so I suspect static web assets will work just fine in this scenario.

• The canonical example for this scenario is Web App "hosts" Webassembly App.

10 - Multitargeting app references single targeting library (browser)

App multitargets but the library only targets the browser

flowchart TD

subgraph Application
  net8app["net8.0"]
  net8browserapp["net8.0-browser1.0"]
end

subgraph Library
  net8.0browserlib["net8.0-browser1.0"]
end

Application-->Library

Loading

• Had to add the project reference to the library conditionally:

    <ItemGroup Condition="'$([MSBuild]::GetTargetPlatformIdentifier($(TargetFramework)))' == 'browser'">
      <ProjectReference Include="..\singletargetclasslib\singletargetclasslib.csproj" />
    </ItemGroup>

• Alternatively, could have done the same thing as in scenario 06 conditionally to the TFM being built not being the browser TFM.