ASP .Net SwaggerUI behind proxy-server with path route ( api.domain.com/SomeApi )

Program.cs

namespace SomeAPI
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var builder = WebApplication.CreateBuilder(args);

            var settings = new AppSettings();
            builder.Configuration.GetSection(nameof(AppSettings)).Bind(settings);
            builder.Services.AddSingleton(settings);

            builder.Services.AddControllers();
            builder.Services.AddEndpointsApiExplorer();
            builder.Services.AddSwaggerGen(config =>
            {
                config.SwaggerDoc("v1", new OpenApiInfo { Title = $"{settings.ApiName}", Version = "v1" });
            });

            var app = builder.Build();
            
            app.UseStaticFiles();

            app.UseSwagger(c =>
            {
                c.PreSerializeFilters.Add((swaggerDoc, request) =>
                {
                    const string prefixHeader = "X-Forwarded-Prefix";
                    if (!request.Headers.ContainsKey(prefixHeader))
                        return;

                    var serverUrl = request.Headers[prefixHeader];
                    swaggerDoc.Servers = new List<OpenApiServer>
                    {
                        new() { Description = "API path behind ingress-nginx", Url = serverUrl }
                    };
                });
            });
            app.UseSwaggerUI(config =>
            {
                config.RoutePrefix = string.Empty;
                config.SwaggerEndpoint("swagger/v1/swagger.json", $"{settings.ApiName}");
            });

            app.UseHttpsRedirection();

            app.UseAuthorization();

            app.MapControllers();

            app.Run();
        }
    }
}