How to use HTTP.sys to host Blazor app (.NET 6)

Question

I'm developing a web app using Blazor with .NET 6.0.11. Building the application produces a .exe file that runs Kestrel. How do I change this to HTTP.sys?

When I google for this topic most of the results are from older versions of ASP.NET where code like var host = new WebHostBuilder().UseWebListener( ... goes inside Main() . But Blazor .NET 6 projects have a different structure, there is no Main() and no WebHostBuilder .

The only relevant tutorial I could find covers excellently how to configure either IIS or Kestrel from launchSettings.json but says nothing about HTTP.sys.

My launchSettings.json (which launches as Kestrel) looks like:

{
  "iisSettings": {
    "windowsAuthentication": false,
    "anonymousAuthentication": true,
    "iisExpress": {
      "applicationUrl": "http://localhost:10563",
      "sslPort": 44364
    }
  },
  "profiles": {
    "MyAppName": {
      "commandName": "Project",
      "dotnetRunMessages": true,
      "launchBrowser": true,
      "launchUrl": "http://localhost:10555",
      "applicationUrl": "http://localhost:10555",
      "environmentVariables": {
        "ASPNETCORE_ENVIRONMENT": "Development"
      }
    },
    "IIS Express": {
      "commandName": "IISExpress",
      "launchBrowser": true,
      "environmentVariables": {
        "ASPNETCORE_ENVIRONMENT": "Development"
      }
    }
  }
}

and Program.cs looks like:

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddRazorPages();
builder.Services.AddServerSideBlazor();

// [omitted other services added for my app]    

var app = builder.Build();

if (app.Environment.IsDevelopment())
{
    app.UseDeveloperExceptionPage();
}
else
{
    // Configure the HTTP request pipeline.
    app.UseExceptionHandler("/Error");
    // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
    app.UseHsts();
}

app.UseHttpsRedirection();

app.UseStaticFiles();

app.UseRouting();

app.MapBlazorHub();
app.MapFallbackToPage("/_Host");

app.Run();

The Program.cs doesn't mention anything about json files nor Kestrel, I'm not sure how it actually ends up reading appsettings.json eventually and deciding to use Kestrel.

Background: I created this project initially by following the reference application at learn.microsoft.com.

Answer 1

An answer was found in passing under Configure Windows Authentication in ASP.NET Core .

No changes required to launchSettings.json or appSettings.json ; and the following code should be added to Program.cs , before the statement var app = builder.Build();, obviously:

if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows))
{
    builder.WebHost.UseHttpSys(options =>
    {
        // set options here if desired
    });
}