ApplyCompressionNegotiation build task fails when RCL references a Nuget RCL with StaticWebAssetBasePath set to /

[LostBeard]

Description

Issue

The .Net 9 Blazor WASM compression build task, ApplyCompressionNegotiation, fails due to an unknown issue handling Razor Class Library Nuget packages that use <StaticWebAssetBasePath>/</StaticWebAssetBasePath> when referenced by another Razor Class Library

Reproduction Steps

1. Create a solution with a .Net 9 Razor Class Library (RCL) and set <StaticWebAssetBasePath>/</StaticWebAssetBasePath> in its .csproj.
2. Publish the RCL as a Nuget package (publishing locally is fine)
3. Create a new solution with an .Net 9 Razor Class Library and a .Net 9 Blazor WASM
4. In the RCL, add a PackageReference to the Nuget package from step 2 (a ProjectReference does not trigger the bug)
5. In the Blazor WASM app add a ProjectReference to the RCL project in the same solution
6. Run dotnet publish --nologo --configuration Release --output bin\Publish in the Blazor WASM app folder to see the error.

You get an exception similar to:

D:\users\tj\Projects\Issue4\WebWorkers.Issue4\WebWorkers.Issue4>dotnet publish --nologo --configuration Release --output "D:\users\tj\Projects\Issue4\WebWorkers.Issue4\WebWorkers.Issue4\bin\Publish\"
Restore complete (0.5s)
  RazorClassLibrary1 net9.0 succeeded (3.3s) → D:\users\tj\Projects\Issue4\WebWorkers.Issue4\RazorClassLibrary1\bin\Release\net9.0\RazorClassLibrary1.dll
  RazorClassLibrary1 net9.0 succeeded (0.1s) → D:\users\tj\Projects\Issue4\WebWorkers.Issue4\RazorClassLibrary1\bin\Release\net9.0\RazorClassLibrary1.dll
  WebWorkers.Issue4 failed with 1 error(s) and 1 warning(s) (0.6s)
    C:\Program Files\dotnet\sdk\9.0.100\Sdks\Microsoft.NET.Sdk.StaticWebAssets\targets\Microsoft.NET.Sdk.StaticWebAssets.Compression.targets(323,5): warning : Endpoints not found for compressed asset: example.JsInterop.faux.js.gz D:\users\tj\Projects\Issue4\WebWorkers.Issue4\WebWorkers.Issue4\obj\Release\net9.0\compressed\87ntuufp02-gq62o8712c.gz
    C:\Program Files\dotnet\sdk\9.0.100\Sdks\Microsoft.NET.Sdk.StaticWebAssets\targets\Microsoft.NET.Sdk.StaticWebAssets.Compression.targets(323,5): error MSB4018:
      The "ApplyCompressionNegotiation" task failed unexpectedly.
      System.InvalidOperationException: Endpoints not found for compressed asset: D:\users\tj\Projects\Issue4\WebWorkers
      .Issue4\WebWorkers.Issue4\obj\Release\net9.0\compressed\87ntuufp02-gq62o8712c.gz
         at Microsoft.AspNetCore.StaticWebAssets.Tasks.ApplyCompressionNegotiation.Execute()
         at Microsoft.Build.BackEnd.TaskExecutionHost.Execute()
         at Microsoft.Build.BackEnd.TaskBuilder.ExecuteInstantiatedTask(TaskExecutionHost taskExecutionHost, TaskLogging
      Context taskLoggingContext, TaskHost taskHost, ItemBucket bucket, TaskExecutionMode howToExecuteTask)
  WebWorkers.Issue4 failed (9.7s) → bin\Release\net9.0\wwwroot

Build failed with 1 error(s) and 1 warning(s) in 15.4s

7. Workaround: Disable compression (<CompressionEnabled>false</CompressionEnabled>) in the 2nd solution's Razor Class Library's .csproj and the publish will succeed and all static web assets will compress normally.

This issue started as a report about an issue (#4) with SpawnDev.BlazorJS.WebWorkers.

Repo that has projects to demonstrate the issue: WebWorkers.Issue4

Expected behavior

I expected StaticWebAssetBasePath to work in .Net 9 as it did in .Net 8. This issue did not exist in .Net 8.

Actual behavior

publish builds fail with the error:

The "ApplyCompressionNegotiation" task failed unexpectedly.
      System.InvalidOperationException: Endpoints not found for compressed asset: 

Regression?

Unknown

Known Workarounds

Disable compression with <CompressionEnabled>false</CompressionEnabled> in Razor Class Libraries .csproj.

Configuration

dotnet --info

.NET SDK:
Version: 9.0.100
Commit: 59db016f11
Workload version: 9.0.100-manifests.4a280210
MSBuild version: 17.12.7+5b8665660

Runtime Environment:
OS Name: Windows
OS Version: 10.0.19045
OS Platform: Windows
RID: win-x64
Base Path: C:\Program Files\dotnet\sdk\9.0.100\

.NET workloads installed:
[android]
Installation Source: SDK 9.0.100, VS 17.13.35507.96
Manifest Version: 35.0.7/9.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\9.0.100\microsoft.net.sdk.android\35.0.7\WorkloadManifest.json
Install Type: Msi

[aspire]
Installation Source: SDK 9.0.100, VS 17.11.35327.3
Manifest Version: 8.2.2/8.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\8.0.100\microsoft.net.sdk.aspire\8.2.2\WorkloadManifest.json
Install Type: Msi

[ios]
Installation Source: SDK 9.0.100, VS 17.13.35507.96
Manifest Version: 18.1.9163/9.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\9.0.100\microsoft.net.sdk.ios\18.1.9163\WorkloadManifest.json
Install Type: Msi

[maccatalyst]
Installation Source: SDK 9.0.100, VS 17.13.35507.96
Manifest Version: 18.1.9163/9.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\9.0.100\microsoft.net.sdk.maccatalyst\18.1.9163\WorkloadManifest.json
Install Type: Msi

[maui-windows]
Installation Source: SDK 9.0.100, VS 17.13.35507.96
Manifest Version: 9.0.0/9.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\9.0.100\microsoft.net.sdk.maui\9.0.0\WorkloadManifest.json
Install Type: Msi

[wasm-tools]
Installation Source: SDK 9.0.100
Manifest Version: 9.0.0/9.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\9.0.100\microsoft.net.workload.mono.toolchain.current\9.0.0\WorkloadManifest.json
Install Type: Msi

[wasm-tools-net8]
Installation Source: SDK 9.0.100
Manifest Version: 9.0.0/9.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\9.0.100\microsoft.net.workload.mono.toolchain.net8\9.0.0\WorkloadManifest.json
Install Type: Msi

Configured to use loose manifests when installing new manifests.

Host:
Version: 9.0.0
Architecture: x64
Commit: 9d5a6a9aa4

.NET SDKs installed:
6.0.102 [C:\Program Files\dotnet\sdk]
6.0.202 [C:\Program Files\dotnet\sdk]
6.0.300 [C:\Program Files\dotnet\sdk]
6.0.302 [C:\Program Files\dotnet\sdk]
7.0.100-rc.1.22431.12 [C:\Program Files\dotnet\sdk]
7.0.102 [C:\Program Files\dotnet\sdk]
7.0.200 [C:\Program Files\dotnet\sdk]
8.0.101 [C:\Program Files\dotnet\sdk]
8.0.204 [C:\Program Files\dotnet\sdk]
8.0.303 [C:\Program Files\dotnet\sdk]
8.0.401 [C:\Program Files\dotnet\sdk]
8.0.403 [C:\Program Files\dotnet\sdk]
9.0.100-rc.2.24474.11 [C:\Program Files\dotnet\sdk]
9.0.100 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
Microsoft.AspNetCore.App 6.0.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 6.0.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 6.0.7 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 6.0.35 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 7.0.0-rc.1.22427.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 7.0.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 7.0.3 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 8.0.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 8.0.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 8.0.7 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 8.0.8 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 8.0.10 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 9.0.0-rc.2.24474.3 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 9.0.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 6.0.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 6.0.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 6.0.7 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 6.0.35 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 7.0.0-rc.1.22426.10 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 7.0.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 7.0.3 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.7 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.8 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.10 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.0-rc.2.24473.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 6.0.2 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 6.0.4 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 6.0.7 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 6.0.35 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 7.0.0-rc.1.22427.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 7.0.2 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 7.0.3 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.4 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.7 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.8 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.10 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.0-rc.2.24474.4 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.0 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

Other architectures found:
x86 [C:\Program Files (x86)\dotnet]
registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x86\InstallLocation]

Environment variables:
Not set

global.json file:
Not found

Learn more:
https://aka.ms/dotnet/info

Download .NET:
https://aka.ms/dotnet/download

Other information

See repo: WebWorkers.Issue4

[LostBeard]

One workaround is to disable compression and the publish builds will succeed.

In the Blazor WASM project's .csproj

<PropertyGroup>
    <CompressionEnabled>false</CompressionEnabled>
</PropertyGroup>

Another is to use .Net 8 instead of .Net 9 as the issue does not occur in .Net 8.

[LostBeard]

Better workaround...

Razor Class Libraries that use Nuget packages affected by this bug can set <CompressionEnabled>false</CompressionEnabled> and then the Blazor WASM app can still use compression normally. Maybe the compression stage is being ran twice? Once for the RCL and again for Blazor app?

[nobba]

The workaround with setting compression to false in the wrapper lib does not work for us, when consuming Webworkers in the wrapper class library and then this wrapper in Blazor application. Setting in the application works but this is obviously not a good solution. Strange that you got it working.