gistfile1.cs

namespace MicroGate 
{
	public class Route
	{
		public bool KeepResourceName { get; set; }
		public string BaseUrl { get; set; }
		public Func<string, string, HttpRequest, bool> Authenticate { get; set; }  
		public Func<string, string, HttpRequest, bool> Authorize { get; set; }
		public IEnumerable<Func<string, string, bool>> AdditionalAllowFunctions { get; set; }
		public Func<string, string, WebRequest, WebRequest> RequestTransfroms { get; set; }
		public Func<string, string, HttpResonse, HttpResonse> ResonseTransfroms { get; set; }
	}

	public class IRouteCollection : IDictionary<string, Route>
	{
		public AddRoute(string resourceName, string baseUrl, bool keepResourceName, 
			Func<string, string, HttpRequest, bool> authenticate,  
			Func<string, string, HttpRequest, bool> authorize,  
			Func<string, string, WebRequest, WebRequest> transformRequest,
			Func<string, string, HttpResonse, HttpResonse> transformResponse
		);
	}

	public class ApiGatewayController : ApiController
	{
		private readonly IRouteCollection Routes;

		public ApiGatewayController(ApiGatewaySettings settings)
		{
			Routes = settings.Routes;
		}

		public HttpResonse Route(string resource, string path)
		{
			var requestString = Request.Url.PathAndQuery;
			var route = Routes[resource];
			var absolutePathOut = route.route.KeepResourceName ? String.Format("{0}/{1}", resource, path) : path;
			var absoluteUrlOut = String.Format("{0}/{1}", route.BaseUrl, absolutePathOut);

			if (!route.Authenticate(resource, path, Request))
				return new HttpResonse();
			if (!route.Authorize(resource, path, Request))
				return new HttpResonse();
			foreach (var func in route.AdditionalAllowFunctions)
				if (!func()) 
					return new HttpResonse();

			var request = WebRequest.Create(absoluteUrlOut); 
			request.ContentLength = Request.ContentLength;
			request.ContentType = Request.ContentType;
			request.CreatorInstance = Request.;
			request.Method = Request.HttpMethod;
			request.Headers = Request.Headers;

			var requestTransform = route.RequestTransfroms.Aggregate((acc, next) => next(resource, path, acc(resource, path, request)));
			var finalRequest = requestTransform(request);
			var webResponse = request.GetResonse();

			var response = // TODO
			var responseTransform = route.ResponseTransforms.Aggregate((acc, next) => next(resource, path, acc(resource, path, response)));
			var finalResponse = responseTransform(response);
			return finalResponse;
		}
	}
}

routes.MapRoute("Name", String.Format("{0}/{resource}/{*path}", pathToGateway), new { controller = ..., action = ... });