OpenAPIReference does not work for SDK generators that create C# output in a folder

[darrelmiller]

Describe the bug

The following build action is executed when you use a SDK generator that uses OutputPath to place the generated C# files.

      <Compile Include="@(_Directories -> '%(Identity)/**/*.$(DefaultLanguageSourceExtension)')"
          Exclude="@(Compile)"
          Condition="'$(DefaultLanguageSourceExtension)' != '.ts'">
        <SourceDocument>%(_Directories.FullPath)</SourceDocument>
      </Compile>

aspnetcore/src/Tools/Extensions.ApiDescription.Client/src/build/Microsoft.Extensions.ApiDescription.Client.targets

Line 129 in 64c3711

<Compile Include="@(_Directories -> '%(Identity)/**/*.$(DefaultLanguageSourceExtension)')"

This outputs a CSC command that includes the globbed path as a parameter. From my tests CSC doesn't appear to support path globbing.

To Reproduce

Add an OutputPath value to the OpenAPIReference in the csproj file. Unfortunately I think NSwag fails with this setting so it isn't as easy to see the final error. You first need to fix the NSwag .targets file. I can provide full steps to repro using kiota as a SDK generator if needed.

Exceptions (if any)

This produces the following error at build time.

CSC : error CS2021: File name 'obj\sdk/**/*..cs' is empty, contains invalid characters, has a drive specification without an absolute path, or is too long

I think the extra dot is a problem too, but even after removing that, the globbing is still a problem.

Further technical details

I tried this on .net 5 and 6. Same error.

[dougbu]

I think the extra dot is a problem too, but even after removing that, the globbing is still a problem.

The globbing might be an issue but the dot definitely is. Could you please try removing that period and report the new error (if any)❔

[darrelmiller]

@dougbu Removing the dot produces the same error from CSC.

[dougbu]

Removing the dot produces the same error from CSC.

Is the error now CSC : error CS2021: File name 'obj\sdk/**/*.cs' is empty❔ I ask because something is weird if the Include isn't populating the @(Compile) item group as expected.

I could probably use a binary log from your test failure because I don't have a generator that creates directories on my machine.

[darrelmiller]

This is what I get when I remove the dot from the compile action.

[darrelmiller]

The generator tool isn't yet in a public feed, so you have to jump through a couple of hoops to install the generator. https://github.com/microsoft/kiota/blob/main/docs/generator/tool.md

and the targets/props files are very simple

<?xml version="1.0" encoding="utf-8" standalone="no"?>
<Project>
  <!-- Reset well-known metadata of the code generator item groups to make NSwag C# generator the default. -->
  <ItemDefinitionGroup>
    <OpenApiReference>
      <CodeGenerator>KiotaCSharp</CodeGenerator>
    </OpenApiReference>
    <OpenApiProjectReference>
      <CodeGenerator>KiotaCSharp</CodeGenerator>
    </OpenApiProjectReference>
  </ItemDefinitionGroup>
</Project>

<?xml version="1.0" encoding="utf-8" standalone="no"?>
<Project>

  <!-- OpenApiReference support for C# -->

  <Target Name="GenerateKiotaCSharp">
    <ItemGroup>
      <!-- @(CurrentOpenApiReference) item group will never contain more than one item. -->
      <CurrentOpenApiReference>
        <Command>kiota -d %(FullPath) -o %(OutputPath) -l CSharp  -c %(ClassName) -n %(Namespace)</Command>
      </CurrentOpenApiReference>
    </ItemGroup>

    <Message Importance="high" Text="%0AGenerateKiotaCSharp:" />
    <Message Importance="high" Text="  %(CurrentOpenApiReference.Command)" />

    <Exec Command="%(CurrentOpenApiReference.Command)" LogStandardErrorAsError="true" />
  </Target>
 
</Project>

[dougbu]

Something strange is going on because item groups support globbing, including the ** part. I'll dive deeper later today and see what I'm missing…

Thanks for contacting us.
We're moving this issue to the .NET 7 Planning milestone for future evaluation / consideration. Because it's not immediately obvious that this is a bug in our framework, we would like to keep this around to collect more feedback, which can later help us determine the impact of it. We will re-evaluate this issue, during our next planning meeting(s).
If we later determine, that the issue has no community involvement, or it's very rare and low-impact issue, we will close it - so that the team can focus on more important and high impact issues.
To learn more about what to expect next and how this issue will be handled you can read more about our triage process here.

[dougbu]

The root cause here is dotnet/msbuild#3274. Globbing inside an item transform apparently doesn't work. /fyi @rainersigwald

I have a workaround and will put up a PR to fix things for 7.0.0-preview1 in a bit. Is testing w/ our nightly builds sufficient for now❔

[darrelmiller]

@dougbu I can definitely test with the nightly build.