Resolve native assemblies from NuGet package

Is your feature request related to a problem? Please describe. I have a plugin with a dependency on Microsoft.CognitiveServices.Speech, which has native dependencies in the runtimes folder that are resolved per platform. When the P/Invoke call occurs from inside Microsoft.CognitiveServices.Speech after resolving the plugin with PluginLoader.CreateFromAssemblyFile, I get a DllNotFoundException.

Describe the solution you’d like I’d like the PluginLoader to also search the runtimes folder in the base path for the AssemblyLoadContext so that I do not get the DllNotFoundException for the native dependency.

Describe alternatives you’ve considered Haven’t started thinking about alternatives.

Additional context No additional context.

[rozele]

Thanks @natemcmaster - the <TargetsForTfmSpecificContentInPackage> did the trick

[natemcmaster]

I can setup a .nuspec file to get the plugins folder, but I was wondering if you had any tips / ran into this issue and figured out how to inform MSBuild to include the plugins folder without creating a .nuspec.

Disclaimer first…if you’re not familiar with MSBuild targets, properties, and item groups, it’s probably better to use a nuspec file. I usually recommend nuspec for complex packing tasks because I think the “API” for customizing a package via csproj is awful.

Nuspec generation in csproj relies on MSBuild items to tell it what to pack. There are a few magic default settings which pick up build outputs for most simple class libraries and console tools. But the magic falls apart when you need to include generated content (such as a plugins folder). You can write your own magic by adding files to the TfmSpecificPackageFile item group as a part of a target that is listed in the TargetsForTfmSpecificContentInPackage property. I haven’t tested this on my own, but I imagine the result would look something like this:

<PropertyGroup>
  <TargetsForTfmSpecificContentInPackage>BuildPlugin;$(TargetsForTfmSpecificContentInPackage)</TargetsForTfmSpecificContentInPackage>
</PropertyGroup>
 
<Target Name="BuildPlugin" BeforeTargets="CoreBuild">
  <PropertyGroup>
    <MyPluginOutputPath>$(OutputPath)/plugins/MyPlugin/</MyPluginOutputPath>
  </PropertyGroup>

  <MSBuild 
    Projects="..\MyPlugin\MyPlugin.csproj"
    Targets="Publish" 
    Properties="Configuration=$(Configuration);PublishDir=$(MyPluginOutputPath)" />

  <ItemGroup>
    <TfmSpecificPackageFile Include="$(MyPluginOutputPath)**/*">
      <PackagePath>tools/$(TargetFramework)/any/plugins/MyPlugin/</PackagePath>
    </TfmSpecificPackageFile>
  </ItemGroup>

</Target>

By the way, checkout https://github.com/dotnet/sdk/blob/master/src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.PackTool.targets and https://github.com/NuGet/NuGet.Client/blob/dev/src/NuGet.Core/NuGet.Build.Tasks.Pack/NuGet.Build.Tasks.Pack.targets to see what the SDK is doing under the hood.