Double-compression when trying to host pre-compressed (`.gz`, `.br`) files via MapStaticAssets

[Fydar]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

When trying to host "pre-compressed" files via MapStaticAssets the server seems to compress the file twice. It doesn't know how to handle the file.

I'm trying to host built Unity game artefacts which I would much rather store in a compressed format on disk.

Expected Behavior

For pre-compressed files to be able to be hosted via MapStaticAssets, whether under the file name including the compression format (.br and .gz) or under the non-compressed name, I don't know.

Steps To Reproduce

Attempt to host a file in MapStaticAssets that is pre-compressed.

Exceptions (if any)

No response

.NET Version

.NET SDK: 9.0.200

Anything else?

No response

[javiercn]

@Fydar thanks for contacting us.

What version of the .NET SDK are you using?

[Fydar]

Updated issued with .NET version (.NET SDK: 9.0.200)

[Fydar]

My workaround for this issue is to continue hosting the files using UseStaticFiles from a different directory from the wwwroot (in this case, a folder called precompressed).

var provider = new FileExtensionContentTypeProvider();
provider.Mappings.Clear();
provider.Mappings[".js"] = "application/javascript";
provider.Mappings[".br"] = "application/octet-stream";

app.UseStaticFiles(new StaticFileOptions
{
    FileProvider = new PhysicalFileProvider(
        Path.Combine(builder.Environment.ContentRootPath, "precompressed")),
    ContentTypeProvider = provider,
    OnPrepareResponse = context =>
    {
        var headers = context.Context.Response.Headers;

        if (context.File.Name.EndsWith(".br", StringComparison.OrdinalIgnoreCase))
        {
            headers.ContentEncoding = "br";

            if (context.File.Name.Contains(".wasm", StringComparison.OrdinalIgnoreCase))
            {
                headers.ContentType = "application/wasm";
            }
            else if (context.File.Name.Contains(".js", StringComparison.OrdinalIgnoreCase))
            {
                headers.ContentType = "application/javascript";
            }
            else if (context.File.Name.Contains(".data", StringComparison.OrdinalIgnoreCase))
            {
                headers.ContentType = "application/octet-stream";
            }
        }
    }
});

[javiercn]

@Fydar what are the extensions for the files?

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