Add Web API controller endpoint to Kestrel worker project

I have a .NET Core worker project with TCP pipelines and want to add one HTTP controller endpoint to it. I basically

created a new worker project (for reproduction purposes)
in its csproj file I added <FrameworkReference Include="Microsoft.AspNetCore.App" /> to the item group to gain access to the webbuilder stuff
installed the package Microsoft.AspNetCore.Mvc.Core
created a Startup class

internal class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddMvc(); // not sure if I even need this
        services.AddControllers();
    }

    public void Configure(IApplicationBuilder applicationBuilder)
    {
        applicationBuilder.UseRouting();
        applicationBuilder.UseEndpoints(endpoints => { endpoints.MapControllers(); });
    }
}

configured Kestrel in the Program class

public class Program
{
    public static void Main(string[] args)
    {
        CreateHostBuilder(args).Build().Run();
    }

    public static IHostBuilder CreateHostBuilder(string[] args) =>
        Host.CreateDefaultBuilder(args)
            .ConfigureWebHostDefaults(webHostBuilder =>
            {
                webHostBuilder.UseKestrel(kestrelServerOptions =>
                {
                    kestrelServerOptions.ListenLocalhost(5000); // this will be a config value
                }).UseStartup<Startup>();
            })
            .ConfigureServices((hostContext, services) =>
            {
                services.AddHostedService<Worker>();
            });
}

created a controller for testing purposes

[ApiController]
[Route("[controller]")]
internal class UsersController : ControllerBase
{
    [HttpGet]
    public async Task<ActionResult> Test()
    {
        return Ok();
    }
}

I run the project and call GET http://localhost:5000/users
I would expect a 200 but get a 404 and the debugger does not hit the controller endpoint

Does someone know what I'm missing?

Solution

You need to specify the default route on method if you want this to be work

[ApiController]
[Route("[controller]")]
   public class UsersController : ControllerBase
    {
     [Route("")]
     [HttpGet]
     public async Task<ActionResult> Test()
       {
          return Ok();
       } 
    }

And Second thing is make the controller public