public static IHostBuilder CreateHostBuilder(string[] args) =>
            Host.CreateDefaultBuilder(args)
                .ConfigureAppConfiguration((hostingContext, config) =>
                {
                    config.AddXmlFile("appsettings.xml", optional: true,  reloadOnChange: true);
                    config.AddJsonFile("appsettings.json", optional: false,  reloadOnChange: true);
                    config.AddJsonFile($"appsettings.{hostingContext.HostingEnvironment.EnvironmentName}.json", optional: true,  reloadOnChange: true);
                })
                .ConfigureWebHostDefaults(webBuilder =>
                {
                    webBuilder.UseStartup<Startup>();
                });
              }

public class VehicleOptions
{
    public int Quantity { get; set; }
}

public class FakeVehicleService
{
   private readonly VehicleOptions options;

    public FakeCustomersService(IOptions<VehicleOptions> options)
    {
        this.options = options.Value;
    }
}
       

        
      public void ConfigureServices(IServiceCollection services)
      {
          services.Configure<VehicleOptions>(Configuration.GetSection("VehicleOptions"));
      }
    }

  public void ConfigureServices(IServiceCollection services)
        {
            var vehicleOptions = new VehicleOptions();
            Configuration.GetSection("VehicleOptions").Bind(vehicleOptions);
            services.AddSingleton(vehicleOptions);

            services.Configure<VehicleOptions>(Configuration.GetSection("VehicleOptions"));
        }

public class FakeVehicleService
{
   private readonly VehicleOptions options;

    public FakeCustomersService(VehicleOptions options)
    {
        this.options = options;
    }
}

 public void ConfigureServices(IServiceCollection services)
 {
     services
         .AddMvc(options => options.RespectBrowserAcceptHeader = true)
         .AddXmlSerializerFormatters();
 }

// GET api/customers/10
// GET api/customers/10.json
// GET api/customers/10.xml

[Route("api/[controller]")]
public class CustomersController : ControllerBase
{
    [FormatFilter]
    [HttpGet("{id:int}.{format?}")]
    public IActionResult GetById(int id)
    {
        if (!customerRepository.IsExists(id))
            return NotFound();

        var customer = customerRepository.Get(id);

        return Ok(customer);
    }
}