Debugger: The request reached the end of the pipeline without executing the endpoint: 'Fallback {*path:nonfile}'

[Bananas-Are-Yellow]

Using the HelloWorld sample, I created a launch.json file as follows:

{
    "version": "0.2.0",
    "configurations": [
        {
            "type": "blazorwasm",
            "name": "Launch and Debug Blazor WebAssembly Application",
            "request": "launch",
            "hosted": true,
            "program": "${workspaceFolder}/src/HelloWorld.Server/bin/Debug/net7.0/HelloWorld.Server.dll",
            "cwd": "${workspaceFolder}/src/HelloWorld.Server",
            "url": "http://localhost:5000"
        }
    ]
}

When I go to Run and Debug (Ctrl+Shift+D) and start debugging, I get this output:

info: Microsoft.AspNetCore.Hosting.Diagnostics[1]
      Request starting HTTP/1.1 GET http://localhost/_framework/debug/ws-proxy?browser=ws%3A%2F%2F127.0.0.1%3A46481%2Fdevtools%2Fbrowser%2F89a7c53f-6382-4440-b727-974415bb8174 - -
Microsoft.AspNetCore.Hosting.Diagnostics: Information: Request starting HTTP/1.1 GET http://localhost/_framework/debug/ws-proxy?browser=ws%3A%2F%2F127.0.0.1%3A46481%2Fdevtools%2Fbrowser%2F89a7c53f-6382-4440-b727-974415bb8174 - -

Then there are a few lines about loading DLLs and skipping load symbols, followed by this error:

fail: Microsoft.AspNetCore.Server.Kestrel[13]
      Connection id "0HMP4BRK8A45B", Request id "0HMP4BRK8A45B:00000001": An unhandled exception was thrown by the application.
      System.InvalidOperationException: The request reached the end of the pipeline without executing the endpoint: 'Fallback {*path:nonfile}'. Please register the EndpointMiddleware using 'IApplicationBuilder.UseEndpoints(...)' if using routing.
         at Microsoft.AspNetCore.Builder.ApplicationBuilder.<>c.<Build>b__18_0(HttpContext context)
         at Microsoft.AspNetCore.StaticFiles.StaticFileMiddleware.Invoke(HttpContext context)
         at Microsoft.AspNetCore.Components.WebAssembly.Server.ContentEncodingNegotiator.InvokeAsync(HttpContext context)
         at Microsoft.AspNetCore.Builder.ComponentsWebAssemblyApplicationBuilderExtensions.<>c__DisplayClass0_0.<<UseBlazorFrameworkFiles>b__2>d.MoveNext()
      --- End of stack trace from previous location ---
         at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
         at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)
Microsoft.AspNetCore.Server.Kestrel: Error: Connection id "0HMP4BRK8A45B", Request id "0HMP4BRK8A45B:00000001": An unhandled exception was thrown by the application.

I don't have a launchSettings.json file, just a launch.json file.

Any idea what's going on here?

[Bananas-Are-Yellow]

I've solved it. A call to UseWebAssemblyDebugging needs to be made in the Startup.Configuration method in the Server project.

    member this.Configure(app: IApplicationBuilder, env: IWebHostEnvironment) =
        if env.IsDevelopment() then
            app.UseWebAssemblyDebugging()

        app
            .UseAuthentication()
            .UseRemoting()
            .UseStaticFiles()
            .UseRouting()
            .UseBlazorFrameworkFiles()
            .UseEndpoints(fun endpoints ->
#if DEBUG
                endpoints.UseHotReload()
#endif
                endpoints.MapBlazorHub() |> ignore
                endpoints.MapFallbackToBolero(Index.page) |> ignore)
        |> ignore

[Tarmil]

Ah, yes. This would be worth adding in the project template.

[Tarmil]

This was added in version 0.21.11 of the project template.