OwinRouter

OwinRouter.cs

using System;
    using System.Collections.Generic;
    using System.Threading.Tasks;
    using Microsoft.Owin;
    using AppFunc = System.Func<System.Collections.Generic.IDictionary<string, object>, System.Threading.Tasks.Task>;
    using MidFunc = System.Func<
      System.Func<System.Collections.Generic.IDictionary<string, object>, System.Threading.Tasks.Task>,
      System.Func<System.Collections.Generic.IDictionary<string, object>, System.Threading.Tasks.Task>>;

    public class OwinRouter
    {
        private readonly Dictionary<string, AppFunc> _hosts = new Dictionary<string, AppFunc>();

        public void AddHost(string hostname, AppFunc appFunc)
        {
            _hosts.Add(hostname, appFunc);
        }

        public void AddHost(string hostname, MidFunc midFunc)
        {
            var appFunc = midFunc(env =>
            {
                var context = new OwinContext(env);
                context.Response.StatusCode = 404;
                context.Response.ReasonPhrase = "OK";
                return Task.CompletedTask;
            });
            AddHost(hostname, appFunc);
        }

        public AppFunc AppFunc
        {
            get
            {
                return env =>
                {
                    var context = new OwinContext();
                    var host = context.Request.Host.Value;
                    AppFunc route;
                    if (_hosts.TryGetValue(host, out route))
                    {
                        return route(env);
                    }
                    throw new InvalidOperationException("Unknown host.");
                };
            }
        }
    }