LINQPad 5 (.NET Framework) Query to mock API Responses

WebApiMockResponse.linq

<Query Kind="Program">
  <Reference>&lt;RuntimeDirectory&gt;\System.Net.Http.dll</Reference>
  <Reference>&lt;RuntimeDirectory&gt;\System.Windows.Forms.dll</Reference>
  <NuGetReference>Microsoft.AspNet.WebApi.OwinSelfHost</NuGetReference>
  <Namespace>Microsoft.Owin.Hosting</Namespace>
  <Namespace>Owin</Namespace>
  <Namespace>System.Net</Namespace>
  <Namespace>System.Net.Http</Namespace>
  <Namespace>System.Threading.Tasks</Namespace>
  <Namespace>System.Web.Http</Namespace>
  <Namespace>System.Web.Http.Controllers</Namespace>
  <Namespace>System.Web.Http.Dispatcher</Namespace>
  <Namespace>System.Windows.Forms</Namespace>
</Query>

void Main()
{
	var app = WebApp.Start<Startup>(Options.BASE_ADDRESS);

	//If the query runs under LPRun then CMD should be defined and the Console handling code should be executed.
#if CMD
	Console.WriteLine("Press Enter to exit...");
	Console.ReadLine();
	app.Dispose();
	Console.WriteLine("Exiting!!!");
#else
	var button = new Button { Text = "Click to stop server." };
	LINQPad.OutputPanel panel = LINQPad.PanelManager.DisplayControl(button, "Webserver");

	button.Click += (o, e) =>
	{
		app.Dispose();
		panel.Close();
	};
#endif
}

class Options
{
	public const string BASE_ADDRESS = "http://localhost:8080";
	public const string MOCK_RESPONSES_DIRECTORY = @"C:\Temp\MockResponses";
	public const string MOCK_RESPONSE_FILENAME = "mock_response_";
	public const string MOCK_RESPONSE_DEFAULT_SUFFIX = "default";
}

public class ControllerResolver : DefaultHttpControllerTypeResolver
{
	public override ICollection<Type> GetControllerTypes(IAssembliesResolver assembliesResolver)
	{
		var types = Assembly.GetExecutingAssembly().GetExportedTypes();
		return types.Where(i => typeof(IHttpController).IsAssignableFrom(i)).ToList();
	}
}

public class Startup
{
	public void Configuration(IAppBuilder appBuilder)
	{
		var config = new HttpConfiguration();

		//LINQPad classes are nested so we use the ControllerResolver instead of the default one
		config.Services.Replace(typeof(IHttpControllerTypeResolver), new ControllerResolver());

		//Use attributes for routing
		config.MapHttpAttributeRoutes();

		appBuilder.UseWebApi(config);
	}
}

[RoutePrefix("api")]
public class MyController : ApiController
{
	[Route("mock-response/{responseId?}")]
	[HttpGet]
	public async Task<IHttpActionResult> HandleMockRequest(int? responseId = null)
	{
		string requestString = await Request.Content.ReadAsStringAsync();
		string responseFileName = Options.MOCK_RESPONSE_FILENAME + (responseId.HasValue ? responseId.ToString() : Options.MOCK_RESPONSE_DEFAULT_SUFFIX);
		string responseFullFileName = Path.Combine(Options.MOCK_RESPONSES_DIRECTORY, responseFileName);
		string responseContent = File.Exists(responseFullFileName) ? File.ReadAllText(responseFullFileName, Encoding.UTF8) : "<root>non-existing-response</root>";

		HttpResponseMessage httpResponse = new HttpResponseMessage(HttpStatusCode.OK)
		{
			Content = new StringContent(responseContent, Encoding.UTF8, "application/xml")
		};
		httpResponse.Headers.CacheControl = new System.Net.Http.Headers.CacheControlHeaderValue
		{
			NoCache = true,
			NoStore = true,
			MustRevalidate = true,
			MaxAge = TimeSpan.Zero
		};
		return ResponseMessage(httpResponse);
	}
}