Working with ASP.NET MVC

Ooui.AspNetCore/ElementResult.cs

@@ -7,19 +7,20 @@ namespace Ooui.AspNetCore
 {
     public class ElementResult : ActionResult
     {
+        readonly Element element;
+
         public ElementResult (Element element)
         {
-
+            this.element = element;
         }
 
         public override async Task ExecuteResultAsync (ActionContext context)
         {
-            var path = context.HttpContext.Request.Path;
             var response = context.HttpContext.Response;
-
             response.StatusCode = 200;
-            response.ContentType = "text/html";
-            var html = Encoding.UTF8.GetBytes (UI.RenderTemplate (path));
+            response.ContentType = "text/html; charset=utf-8";
+            var sessionId = WebSocketHandler.BeginSession (context.HttpContext, element);
+            var html = Encoding.UTF8.GetBytes (UI.RenderTemplate (WebSocketHandler.WebSocketPath + "?id=" + sessionId));
             response.ContentLength = html.Length;
             using (var s = response.Body) {
                 await s.WriteAsync (html, 0, html.Length).ConfigureAwait (false);

Ooui.AspNetCore/Ooui.AspNetCore.csproj

@@ -6,6 +6,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.Mvc" Version="2.0.0" />
+    <PackageReference Include="Microsoft.AspNetCore.WebSockets" Version="2.0.0" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\Ooui\Ooui.csproj" />

Ooui.AspNetCore/OouiMiddlewareExtensions.cs

@@ -0,0 +1,55 @@
+using System;
+using Ooui.AspNetCore;
+
+namespace Microsoft.AspNetCore.Builder
+{
+    public static class OouiMiddlewareExtensions
+    {
+        public static void UseOoui (this IApplicationBuilder app, string jsPath = "/ooui.js", string webSocketPath = "/ooui.ws", TimeSpan? sessionTimeout = null)
+        {
+            if (string.IsNullOrWhiteSpace (webSocketPath))
+                throw new ArgumentException ("A path to be used for Ooui web sockets must be specified", nameof (webSocketPath));
+            
+            if (string.IsNullOrWhiteSpace (jsPath))
+                throw new ArgumentException ("A path to be used for Ooui JavaScript must be specified", nameof (jsPath));
+
+            WebSocketHandler.WebSocketPath = webSocketPath;
+
+            if (sessionTimeout.HasValue) {
+                WebSocketHandler.SessionTimeout = sessionTimeout.Value;
+            }
+
+            var webSocketOptions = new WebSocketOptions () {
+                KeepAliveInterval = WebSocketHandler.SessionTimeout,
+                ReceiveBufferSize = 4 * 1024
+            };
+            app.UseWebSockets (webSocketOptions);
+
+            app.Use (async (context, next) =>
+            {
+                if (context.Request.Path == jsPath) {
+                    var response = context.Response;
+                    var clientJsBytes = Ooui.UI.ClientJsBytes;
+                    response.StatusCode = 200;
+                    response.ContentLength = clientJsBytes.Length;
+                    response.ContentType = "application/javascript; charset=utf-8";
+                    response.Headers.Add ("Cache-Control", "public, max-age=3600");
+                    using (var s = response.Body) {
+                        await s.WriteAsync (clientJsBytes, 0, clientJsBytes.Length).ConfigureAwait (false);
+                    }
+                }
+                else if (context.Request.Path == WebSocketHandler.WebSocketPath) {
+                    if (context.WebSockets.IsWebSocketRequest) {
+                        await WebSocketHandler.HandleWebSocketRequestAsync (context).ConfigureAwait (false);
+                    }
+                    else {
+                        context.Response.StatusCode = 400;
+                    }
+                }
+                else {
+                    await next ().ConfigureAwait (false);
+                }
+            });
+        }
+    }
+}

Ooui.AspNetCore/WebSocketHandler.cs

@@ -0,0 +1,82 @@
+using System;
+using System.Collections.Concurrent;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Http;
+
+namespace Ooui.AspNetCore
+{
+    public static class WebSocketHandler
+    {
+        public static string WebSocketPath { get; set; } = "/ooui.ws";
+
+        public static TimeSpan SessionTimeout { get; set; } = TimeSpan.FromMinutes (5);
+
+        static readonly ConcurrentDictionary<string, PendingSession> pendingSessions =
+            new ConcurrentDictionary<string, PendingSession> ();
+
+        public static string BeginSession (HttpContext context, Element element)
+        {
+            var id = Guid.NewGuid ().ToString ("N");
+
+            var s = new PendingSession {
+                Element = element,
+                RequestTimeUtc = DateTime.UtcNow,
+            };
+
+            if (!pendingSessions.TryAdd (id, s)) {
+                throw new Exception ("Failed to schedule pending session");
+            }
+
+            return id;
+        }
+
+        public static async Task HandleWebSocketRequestAsync (HttpContext context)
+        {
+            //
+            // Make sure we get a good ID
+            //
+            if (!context.Request.Query.TryGetValue ("id", out var idValues)) {
+                context.Response.StatusCode = StatusCodes.Status400BadRequest;
+                return;
+            }
+
+            var id = idValues.FirstOrDefault ();
+            if (id == null || id.Length != 32) {
+                context.Response.StatusCode = StatusCodes.Status400BadRequest;
+                return;
+            }
+
+            //
+            // Find the pending session
+            //
+            if (!pendingSessions.TryRemove (id, out var pendingSession)) {
+                context.Response.StatusCode = StatusCodes.Status400BadRequest;
+                return;
+            }
+
+            //
+            // Reject the session if it's old
+            //
+            if ((DateTime.UtcNow - pendingSession.RequestTimeUtc) > SessionTimeout) {
+                context.Response.StatusCode = StatusCodes.Status400BadRequest;
+                return;
+            }
+
+            //
+            // OK, Run
+            //
+            var token = CancellationToken.None;
+            var webSocket = await context.WebSockets.AcceptWebSocketAsync ("ooui");
+            var session = new Ooui.UI.Session (webSocket, pendingSession.Element, token);
+            await session.RunAsync ().ConfigureAwait (false);
+        }
+
+        class PendingSession
+        {
+            public Element Element;
+            public DateTime RequestTimeUtc;
+        }
+    }
+}

Ooui/UI.cs

@@ -27,17 +27,19 @@ namespace Ooui
 
         static readonly byte[] clientJsBytes;
 
+        public static byte[] ClientJsBytes => clientJsBytes;
+
         public static string Template { get; set; } = $@"<!DOCTYPE html>
 <html>
 <head>
-  <title>@ElementPath</title>
+  <title>@Title</title>
   <meta name=""viewport"" content=""width=device-width, initial-scale=1"" />
   <style>@Styles</style>
 </head>
 <body>
 <div id=""ooui-body""></div>
 <script src=""/ooui.js""></script>
-<script>ooui(""@ElementPath"");</script>
+<script>ooui(""@WebSocketPath"");</script>
 </body>
 </html>";
 
@@ -297,9 +299,9 @@ namespace Ooui
             }
         }
 
-        public static string RenderTemplate (string elementPath)
+        public static string RenderTemplate (string webSocketPath)
         {
-            return Template.Replace ("@ElementPath", elementPath).Replace ("@Styles", rules.ToString ());
+            return Template.Replace ("@WebSocketPath", webSocketPath).Replace ("@Styles", rules.ToString ());
         }
 
         class DataHandler : RequestHandler
@@ -454,7 +456,7 @@ namespace Ooui
             Console.ResetColor ();
         }
 
-        class Session
+        public class Session
         {
             readonly WebSocket webSocket;
             readonly Element element;

PlatformSamples/AspNetCoreMvc/Controllers/HomeController.cs

@@ -15,8 +15,8 @@ namespace AspNetCoreMvc.Controllers
     {
         public IActionResult Index()
         {
-            var button = new Button ();
-            return new ElementResult (button);
+            var element = new Label { Text = "Hello Oooooui from Controller" };
+            return new ElementResult (element);
         }
 
         public IActionResult About()

PlatformSamples/AspNetCoreMvc/Startup.cs

@@ -28,19 +28,18 @@ namespace AspNetCoreMvc
         // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
         public void Configure (IApplicationBuilder app, IHostingEnvironment env)
         {
-            if (env.IsDevelopment())
-            {
+            if (env.IsDevelopment ()) {
                 app.UseDeveloperExceptionPage ();
             }
-            else
-            {
+            else {
                 app.UseExceptionHandler ("/Home/Error");
             }
 
             app.UseStaticFiles ();
 
-            app.UseMvc(routes =>
-            {
+            app.UseOoui ();
+
+            app.UseMvc (routes => {
                 routes.MapRoute (
                     name: "default",
                     template: "{controller=Home}/{action=Index}/{id?}");