잉여장비목록 화면 추가(최효준s)

Project/OWIN/StartupSSE.cs

@@ -0,0 +1,101 @@
+using Microsoft.Owin;
+using Owin;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Threading.Tasks;
+using System.Web.Http;
+
+namespace Project.OWIN
+{
+    public class StartupSSE
+    {
+
+
+        public void Configuration(IAppBuilder app)
+        {
+            var api = new Api();
+            app.Run(context => api.Invoke(context));
+        }
+
+        public class Subscriber
+        {
+            private StreamWriter _writer;
+            private TaskCompletionSource<bool> _tcs;
+            public Subscriber(Stream body, TaskCompletionSource<bool> tcs)
+            {
+                this._writer = new StreamWriter(body);
+                this._tcs = tcs;
+            }
+
+            public async void WriteAsync(string message)
+            {
+                try
+                {
+                    _writer.Write(message);
+                    _writer.Flush();
+                }
+                catch (Exception e)
+                {
+                    if (e.HResult == -2146232800) // non-existent connection
+                        _tcs.SetResult(true);
+                    else
+                        _tcs.SetException(e);
+                }
+            }
+        }
+
+        public class Api
+        {
+            System.Timers.Timer _timer = new System.Timers.Timer(500);
+            List<Subscriber> _subscribers = new List<Subscriber>();
+            public Api()
+            {
+                _timer.Elapsed += _timer_Elapsed;
+            }
+
+            void _timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
+            {
+                UpdateSubscribers();
+            }
+
+            public void UpdateSubscribers()
+            {
+                Console.WriteLine("updating {0} subscribers", _subscribers.Count);
+                var subscribersCopy = _subscribers.ToList<Subscriber>();
+                var msg = String.Format("Hello async at {0}\n", DateTime.Now);
+                subscribersCopy.ForEach(w => w.WriteAsync(msg));
+                _timer.Start();
+            }
+
+
+            public Task Invoke(IOwinContext context)
+            {
+                SetEventHeaders(context);
+                System.IO.Stream responseStream = context.Environment["owin.ResponseBody"] as Stream;
+                var tcs = new TaskCompletionSource<bool>();
+                var s = CreateSubscriber(responseStream, tcs);
+                tcs.Task.ContinueWith(_ => _subscribers.Remove(s));
+                Console.WriteLine("Add subscriber. Now have {0}", _subscribers.Count);
+                s.WriteAsync("Registered\n");
+                _timer.Start();
+                return tcs.Task;
+            }
+
+            private Subscriber CreateSubscriber(System.IO.Stream responseStream, TaskCompletionSource<bool> tcs)
+            {
+                var s = new Subscriber(responseStream, tcs);
+                _subscribers.Add(s);
+                return s;
+            }
+
+            private static void SetEventHeaders(IOwinContext context)
+            {
+                context.Response.ContentType = "text/eventstream";
+                context.Response.Headers["Transfer-Encoding"] = "chunked";
+                context.Response.Headers["cache-control"] = "no-cache";
+            }
+        }
+    }
+}