[Blazor] UseBlazorFrameworkFiles not working as intended

[yasinkavakli]

Describe the bug

When using UseBlazorFrameworkFiles, I'm getting 404 on all DLL files.

To Reproduce

Create a new Blazor WASM project with In-App authentication, ASP.NET hosted and PWA.
Open the Startup.cs in the Server project and change the line app.UseBlazorFrameworkFiles(); to app.UseBlazorFrameworkFiles("/app");. After that, open your wwwroot/index.html in the Client project and change <base href="/" /> to <base href="/app" />. After that, open your Index.razor in the client project and change @page "/" to @page "/app". Then run the app with F5 and you'll get 404s on all DLLs that Blazor wants to load.

Example repo: https://github.com/Coupz/UseBlazorFrameworkFiles

Further technical details

• ASP.NET Core version: .NET 5
• Include the output of dotnet --info

❯ dotnet --info
.NET SDK (reflecting any global.json):
 Version:   5.0.100
 Commit:    5044b93829

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.19042
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\5.0.100\

Host (useful for support):
  Version: 5.0.0
  Commit:  cf258a14b7

.NET SDKs installed:
  3.1.404 [C:\Program Files\dotnet\sdk]
  5.0.100 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.All 2.1.23 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.App 2.1.23 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.9 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.10 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 2.1.23 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.10 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 3.1.9 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 3.1.10 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.0 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

• The IDE (VS / VS Code/ VS4Mac) you're running on, and its version
  Visual Studio 2019 16.8.2
  VSCode October 2020 (version 1.51)

Expected outcome:

That I have to move the index.html to a subfolder of wwwroot -> wwwroot/app/index.html and that I can put other static HTML files/pages to the default wwwroot folder, which still get served by Kestrel but without loading Blazor.

[javiercn]

@coupz thanks for contacting us.

You also need to change StaticWebAssetBasePath on the client project to "/app" but we currently have a bug in 5.0 that is preventing this from working, it will be fixed in a following patch release.

[yasinkavakli]

Thank you @javiercn, so you mean to add StaticWebAssetBasePath to the csproj file like this:

  <PropertyGroup>
    <TargetFramework>net5.0</TargetFramework>
    <ServiceWorkerAssetsManifest>service-worker-assets.js</ServiceWorkerAssetsManifest>
    <StaticWebAssetBasePath>app</StaticWebAssetBasePath>
  </PropertyGroup>

And then the files in the wwwroot folder (index.html, about.html, pricing.html) would be statically served by the Kestrel server and everything under "/app" would be picked up by blazor, because there I would have another index.html which loads blazor.webassembly.js. Did I understand that correctly?

[javiercn]

@coupz for the wwwroot folder on the Blazor webassembly project, that's it.

That said, we have an ongoing bug where the framework files don't correctly respect the SWA base path, so this won't work until we fix it in the following weeks.

[yasinkavakli]

Alright, thank you very much!

[yasinkavakli]

Hi @javiercn, today was the release of .NET 5.0.1 where this issue was mentioned with the StaticWebAssetBasePath but I still can't get it to work. I've updated the demo repo (url in my first post).
Do I miss something here? I also tried to move everything under wwwroot to the folder wwwroot\app which didn't work either.

[javiercn]

@coupz did you clean the bin, obj folders after updating the SDK?

if you run dotnet publish do the files end up in the right location? app/_framework/...

[yasinkavakli]

Hi Javier,

my publish folder wwwroot looks like this:

It doesn't change with dotnet publish -c Release either and on https://localhost:5001 and https://localhost:5001/app I'm receiving 404 without any exceptions in the console.
I also deleted the repo locally and cloned from my demo repo again and build it again.