Blazor server - Static files from wwwroot doesn't load using IIS (404)

[lhidrovo]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

I Have a Blazor Server .NET 8 App. In my local environment using the name "Development" the application runs correctly. However, after hosting the application on an IIS server side, all the content references at wwwroot are returning 404 like CSS, images, and javascript files. It can't find any resources (wwroot) even though the folder does exist on the server. As additional information, the application is hosted by https://www.contoso.com/{MYAPP} and I have configured the App base path described in the documentation at App Base Path. Everything works in the dev environment, but no int the server.

Some code examples in the program file
WebApplicationBuilder builder = WebApplication.CreateBuilder(args);

builder.WebHost.UseWebRoot("wwwroot");
builder.WebHost.UseStaticWebAssets();

......

WebApplication app = builder.Build();

app.UseStaticFiles("/App/Treatment");
app.UsePathBase("/App/Treatment");

....
app.UseHttpsRedirection();

app.UseRouting();
app.UseCors();

app.UseAntiforgery();

app.UseCookiePolicy();
app.UseAuthentication();
app.UseAuthorization();
app.UseSession();
app.UseResponseCaching();

app.MapDefaultControllerRoute();

app.MapRazorComponents<App>()
.AddInteractiveServerRenderMode();

app.Run();

App.razor
<base href="/App/Treatment/" />

Expected Behavior

No response

Steps To Reproduce

No response

Exceptions (if any)

No response

.NET Version

8.0.100

Anything else?

[christolo]

As a workaround for now I created a virtual directory in IIS for wwwroot and then setup a rewrite rule for /appsettings.json -> wwwroot/appsettings.json until we figure out the issue.

[annibalh07]

I believe the issue is related to the UseStaticFiles middleware and the dotnet run command, causing an incorrect physical path where it is executed. To address this, I have implemented a workaround by specifying the physical path as follows:

WebApplication app = builder.Build();
app.UseDefaultFiles();

if (builder.Environment.IsDevelopment())
{
    app.UseStaticFiles("/App/Treatment");
}
else
{
    app.UseStaticFiles(new StaticFileOptions()
    {
        FileProvider = new PhysicalFileProvider($@"{AppDomain.CurrentDomain.BaseDirectory}/wwwroot")
    });
}

app.UsePathBase("/App/Treatment");

It worked!

[christolo]

Nice work. I'll give it a go myself. Thanks.

[maxbanas]

I believe the issue is related to the UseStaticFiles middleware and the dotnet run command, causing an incorrect physical path where it is executed. To address this, I have implemented a workaround by specifying the physical path as follows:

WebApplication app = builder.Build();
app.UseDefaultFiles();

if (builder.Environment.IsDevelopment())
{
    app.UseStaticFiles("/App/Treatment");
}
else
{
    app.UseStaticFiles(new StaticFileOptions()
    {
        FileProvider = new PhysicalFileProvider($@"{AppDomain.CurrentDomain.BaseDirectory}/wwwroot")
    });
}

app.UsePathBase("/App/Treatment");

It worked!

This worked for me as well. Thank you! Looks like #51027 may be related?

[azubu23202869]

This doesn't work for me as I still cannot read files under the wwwroot directory.

I added the following code to my code:

app.UseStaticFiles(new StaticFileOptions()
{
    FileProvider = new PhysicalFileProvider($@"{AppDomain.CurrentDomain.BaseDirectory}/wwwroot")
});

[szijarto68]

Not working for me either. I was hopeful to use Blazor for ongoing UI development, but this is a big fail. I've wasted hours trying to get the static files to get served up.

[s-beji]

Hey,

Could you provide a reproduction project to show this issue?
It increases the likelihood that the issue will be picked up in the future

Thanks in advance