moved websocket data streaming to game thread, in order to avoid pote…

…ntially crashing KSP on exit

Telemachus/Telemachus.csproj

@@ -59,11 +59,13 @@
     <Compile Include="src\DataLinkResponsibility.cs" />
     <Compile Include="src\ElseResponsibility.cs" />
     <Compile Include="src\IOPageResponsibility.cs" />
+    <Compile Include="src\IterationToEvent.cs" />
     <Compile Include="src\KSPWebSocketService.cs" />
     <Compile Include="src\PluginLogger.cs" />
     <Compile Include="src\TelemachusBehaviour.cs" />
     <Compile Include="src\TelemachusPartModules.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="src\UpdateTimer.cs" />
     <Compile Include="src\UpLinkDownLinkRate.cs" />
     <Compile Include="src\VesselChangeDetector.cs" />
   </ItemGroup>

Telemachus/src/IterationToEvent.cs

@@ -0,0 +1,22 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Timers;
+using UnityEngine;
+
+namespace Telemachus
+{
+    public class IterationToEvent<E> where E : EventArgs
+    {
+        public event EventHandler<E> Iterated;
+
+        public void update(E eventArgs)
+        {
+            if (Iterated != null)
+            {
+                Iterated(this, eventArgs);
+            }
+        }
+    }
+}

Telemachus/src/KSPWebSocketService.cs

@@ -27,43 +27,46 @@ public class KSPWebSocketService : IWebSocketService
 
         private Regex matchJSONAttributes = new Regex(@"[\{""|,""|,""]([^"":]*)"":([^:]*)[,|\}]");
 
-        private Timer streamTimer = new Timer();
+        private IterationToEvent<UpdateTimerEventArgs> gameLoopEvent = null;
+        private UpdateTimer streamTimer = new UpdateTimer();
 
         private int streamRate = 500;
         HashSet<string> subscriptions = new HashSet<string>();
         HashSet<string> toRun = new HashSet<string>();
         readonly private System.Object subscriptionLock = new System.Object();
 
-        public KSPWebSocketService(IKSPAPI kspAPI, Servers.AsynchronousServer.ClientConnection clientConnection)
-            : this(kspAPI)
+        public KSPWebSocketService(IKSPAPI kspAPI, Servers.AsynchronousServer.ClientConnection clientConnection, IterationToEvent<UpdateTimerEventArgs> gameLoopEvent)
+            : this(kspAPI, gameLoopEvent)
         {
             this.clientConnection = clientConnection;
             streamTimer.Interval = streamRate;
             streamTimer.Elapsed += streamData;
             streamTimer.Enabled = true;
         }
 
-        public KSPWebSocketService(IKSPAPI kspAPI)
+        public KSPWebSocketService(IKSPAPI kspAPI, IterationToEvent<UpdateTimerEventArgs> gameLoopEvent)
         {
             this.kspAPI = kspAPI;
+            this.gameLoopEvent = gameLoopEvent;
+            gameLoopEvent.Iterated += streamTimer.update;
         }
 
-        private void streamData(object sender, ElapsedEventArgs e)
+        private void streamData(object sender, UpdateTimerEventArgs e)
         {
-            streamTimer.Interval = streamRate;
-
             DataSources dataSources = new DataSources();
 
-            if (toRun.Count + subscriptions.Count > 0)
+            lock (subscriptionLock)
             {
-                try
+                streamTimer.Interval = streamRate;
+
+                if (toRun.Count + subscriptions.Count > 0)
                 {
-                    List<string> entries = new List<string>();
+                    try
+                    {
+                        List<string> entries = new List<string>();
 
-                    APIEntry entry = null;
+                        APIEntry entry = null;
 
-                    lock (subscriptionLock)
-                    {
                         dataSources.vessel = kspAPI.getVessel();
 
                         //Only parse the paused argument if the active vessel is null
@@ -101,22 +104,22 @@ private void streamData(object sender, ElapsedEventArgs e)
                         {
                             sendNullMessage();
                         }
-                    } 
+                    }
+                    catch(NullReferenceException)
+                    {
+                        PluginLogger.debug("Swallowing null reference exception, potentially due to async game state change.");
+                        sendNullMessage();
+                    }
+                    catch (Exception ex)
+                    {
+                        PluginLogger.debug("Closing socket due to potential client disconnect:" + ex.GetType().ToString());
+                        close();
+                    }
                 }
-                catch(NullReferenceException)
+                else
                 {
-                    PluginLogger.debug("Swallowing null reference exception, potentially due to async game state change.");
                     sendNullMessage();
                 }
-                catch (Exception ex)
-                {
-                    PluginLogger.debug("Closing socket due to potential client disconnect:" + ex.GetType().ToString());
-                    close();
-                }
-            }
-            else
-            {
-                sendNullMessage();
             }
         }
 
@@ -159,20 +162,22 @@ public void OpCodeText(object sender, FrameEventArgs e)
         private void rate(string p)
         {
             int proposedRate = 0;
-
-            try
+            lock (subscriptionLock)
             {
-                proposedRate = int.Parse(p);
+                try
+                {
+                    proposedRate = int.Parse(p);
 
-                if (proposedRate >= MAX_STREAM_RATE)
+                    if (proposedRate >= MAX_STREAM_RATE)
+                    {
+                        streamRate = proposedRate;
+                    }
+                }
+                catch (Exception)
                 {
-                    streamRate = proposedRate;
+                    PluginLogger.debug("Swallowing integer parse failure when setting stream rate.");
                 }
             }
-            catch (Exception)
-            {
-                PluginLogger.debug("Swallowing integer parse failure when setting stream rate.");
-            }
         }
 
         private string[] splitString(string p)
@@ -228,13 +233,13 @@ public void Shutdown(EventArgs e)
 
         private void close()
         {
-            streamTimer.Stop();
+            gameLoopEvent.Iterated -= streamTimer.update;
             clientConnection.tryShutdown();
         }
 
         public IWebSocketService buildService(Servers.AsynchronousServer.ClientConnection clientConnection)
         {
-            return new KSPWebSocketService(kspAPI, clientConnection);
+            return new KSPWebSocketService(kspAPI, clientConnection, gameLoopEvent);
         }
 
         #region Unused Callbacks

Telemachus/src/TelemachusBehaviour.cs

@@ -4,12 +4,19 @@
 using System;
 using System.Collections.Generic;
 using System.Text;
+using System.Timers;
 using UnityEngine;
 
 namespace Telemachus
 {
     class TelemachusBehaviour : MonoBehaviour
     {
+        #region Constants
+
+        private float MICRO_SECONDS = 1000.0f;
+
+        #endregion
+
         #region Fields
 
         public static GameObject instance;
@@ -27,6 +34,7 @@ class TelemachusBehaviour : MonoBehaviour
         private static IOPageResponsibility ioPageResponsibility = null;
         private static VesselChangeDetector vesselChangeDetector = null;
         private static KSPWebSocketService kspWebSocketService = null;
+        private static IterationToEvent<UpdateTimerEventArgs> kspWebSocketDataStreamer = new IterationToEvent<UpdateTimerEventArgs>();
         private static bool isPartless = false;
 
         static public string getServerPrimaryIPAddress()
@@ -64,7 +72,8 @@ static private void startDataLink()
                     webSocketconfig.bufferSize = 300;
                     webSocketServer = new Servers.MinimalWebSocketServer.Server(webSocketconfig);
                     webSocketServer.ServerNotify += WebSocketServerNotify;
-                    kspWebSocketService = new KSPWebSocketService(new KSPAPI(JSONFormatterProvider.Instance, vesselChangeDetector, serverConfig));
+                    kspWebSocketService = new KSPWebSocketService(new KSPAPI(JSONFormatterProvider.Instance, vesselChangeDetector, serverConfig), 
+                        kspWebSocketDataStreamer);
                     webSocketServer.addWebSocketService("/datalink", kspWebSocketService);
                     webSocketServer.subscribeToHTTPForStealing(server);
 
@@ -187,6 +196,7 @@ public void Update()
             if (FlightGlobals.fetch != null)
             {
                 vesselChangeDetector.update(FlightGlobals.ActiveVessel);
+                kspWebSocketDataStreamer.update(new UpdateTimerEventArgs(Time.time * MICRO_SECONDS));
             }
             else
             {

Telemachus/src/UpdateTimer.cs

@@ -0,0 +1,57 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Timers;
+using UnityEngine;
+
+namespace Telemachus
+{
+    public class UpdateTimer
+    {
+        public event EventHandler<UpdateTimerEventArgs> Elapsed;
+        private float lastEventTime = 0.0f;
+
+        private float interval = 0.0f;
+        public float Interval
+        {
+            get { return interval; }
+            set { interval = value; }
+        }
+
+        private bool enabled = false;
+        public bool Enabled
+        {
+            get { return enabled; }
+            set { enabled = value; }
+        }
+
+        public void update(object sender, UpdateTimerEventArgs timeElapsedEventArgs)
+        {
+            if ((timeElapsedEventArgs.Time - lastEventTime > interval) && Enabled)
+            {
+                if (Elapsed != null)
+                {
+                    Elapsed(this, timeElapsedEventArgs);
+                }
+
+                lastEventTime = timeElapsedEventArgs.Time;
+            }
+        }
+    }
+
+    public class UpdateTimerEventArgs : EventArgs
+    {
+        private float time = 0.0f;
+
+        public float Time 
+        {
+            get { return time; }
+        }
+
+        public UpdateTimerEventArgs(float time)
+        {
+            this.time = time;
+        }
+    }
+}

TelemachusTest/src/TelemachusWebSocketServerTest.cs

@@ -31,13 +31,13 @@ public void run()
             VesselChangeDetector vesselChangeDetector = new VesselChangeDetector(false);
             IKSPAPI kspAPI = new DummyKSPAPI(JSONFormatterProvider.Instance, vesselChangeDetector, config);
 
-            webSocketServer.addWebSocketService("/server", new KSPWebSocketService(kspAPI));
-            webSocketServer.subscribeToHTTPForStealing(server);
+            //webSocketServer.addWebSocketService("/server", new KSPWebSocketService(kspAPI,));
+            //webSocketServer.subscribeToHTTPForStealing(server);
 
             // start the HTTP server
-            server.startServing();
-            Console.Read();
-            server.stopServing();
+            //server.startServing();
+            //Console.Read();
+            //server.stopServing();
         }
 
         static void server_ServerNotify(object sender, Servers.NotifyEventArgs e)