Simplify websocket listeners

MediaBrowser.Api/ScheduledTasks/ScheduledTasksWebSocketListener.cs

@@ -58,9 +58,8 @@ namespace MediaBrowser.Api.ScheduledTasks
         /// <summary>
         /// Gets the data to send.
         /// </summary>
-        /// <param name="state">The state.</param>
         /// <returns>Task{IEnumerable{TaskInfo}}.</returns>
-        protected override Task<IEnumerable<TaskInfo>> GetDataToSend(WebSocketListenerState state, CancellationToken cancellationToken)
+        protected override Task<IEnumerable<TaskInfo>> GetDataToSend()
         {
             return Task.FromResult(TaskManager.ScheduledTasks
                 .OrderBy(i => i.Name)

MediaBrowser.Api/Session/SessionInfoWebSocketListener.cs

@@ -79,9 +79,8 @@ namespace MediaBrowser.Api.Session
         /// <summary>
         /// Gets the data to send.
         /// </summary>
-        /// <param name="state">The state.</param>
         /// <returns>Task{SystemInfo}.</returns>
-        protected override Task<IEnumerable<SessionInfo>> GetDataToSend(WebSocketListenerState state, CancellationToken cancellationToken)
+        protected override Task<IEnumerable<SessionInfo>> GetDataToSend()
         {
             return Task.FromResult(_sessionManager.Sessions);
         }

MediaBrowser.Api/System/ActivityLogWebSocketListener.cs

@@ -38,9 +38,8 @@ namespace MediaBrowser.Api.System
         /// <summary>
         /// Gets the data to send.
         /// </summary>
-        /// <param name="state">The state.</param>
         /// <returns>Task{SystemInfo}.</returns>
-        protected override Task<List<ActivityLogEntry>> GetDataToSend(WebSocketListenerState state, CancellationToken CancellationToken)
+        protected override Task<List<ActivityLogEntry>> GetDataToSend()
         {
             return Task.FromResult(new List<ActivityLogEntry>());
         }

MediaBrowser.Controller/Net/BasePeriodicWebSocketListener.cs

@@ -22,8 +22,8 @@ namespace MediaBrowser.Controller.Net
         /// <summary>
         /// The _active connections
         /// </summary>
-        protected readonly List<Tuple<IWebSocketConnection, CancellationTokenSource, Timer, TStateType>> ActiveConnections =
-            new List<Tuple<IWebSocketConnection, CancellationTokenSource, Timer, TStateType>>();
+        protected readonly List<Tuple<IWebSocketConnection, CancellationTokenSource, TStateType>> ActiveConnections =
+            new List<Tuple<IWebSocketConnection, CancellationTokenSource, TStateType>>();
 
         /// <summary>
         /// Gets the name.
@@ -34,9 +34,8 @@ namespace MediaBrowser.Controller.Net
         /// <summary>
         /// Gets the data to send.
         /// </summary>
-        /// <param name="state">The state.</param>
         /// <returns>Task{`1}.</returns>
-        protected abstract Task<TReturnDataType> GetDataToSend(TStateType state, CancellationToken cancellationToken);
+        protected abstract Task<TReturnDataType> GetDataToSend();
 
         /// <summary>
         /// The logger
@@ -80,8 +79,6 @@ namespace MediaBrowser.Controller.Net
 
         protected readonly CultureInfo UsCulture = new CultureInfo("en-US");
 
-        protected bool SendOnTimer => false;
-
         /// <summary>
         /// Starts sending messages over a web socket
         /// </summary>
@@ -97,10 +94,6 @@ namespace MediaBrowser.Controller.Net
 
             Logger.LogDebug("{1} Begin transmitting over websocket to {0}", message.Connection.RemoteEndPoint, GetType().Name);
 
-            var timer = SendOnTimer ?
-                new Timer(TimerCallback, message.Connection, Timeout.Infinite, Timeout.Infinite) :
-                null;
-
             var state = new TStateType
             {
                 IntervalMs = periodMs,
@@ -109,47 +102,13 @@ namespace MediaBrowser.Controller.Net
 
             lock (ActiveConnections)
             {
-                ActiveConnections.Add(new Tuple<IWebSocketConnection, CancellationTokenSource, Timer, TStateType>(message.Connection, cancellationTokenSource, timer, state));
-            }
-
-            if (timer != null)
-            {
-                timer.Change(TimeSpan.FromMilliseconds(dueTimeMs), TimeSpan.FromMilliseconds(periodMs));
-            }
-        }
-
-        /// <summary>
-        /// Timers the callback.
-        /// </summary>
-        /// <param name="state">The state.</param>
-        private void TimerCallback(object state)
-        {
-            var connection = (IWebSocketConnection)state;
-
-            Tuple<IWebSocketConnection, CancellationTokenSource, Timer, TStateType> tuple;
-
-            lock (ActiveConnections)
-            {
-                tuple = ActiveConnections.FirstOrDefault(c => c.Item1 == connection);
+                ActiveConnections.Add(new Tuple<IWebSocketConnection, CancellationTokenSource, TStateType>(message.Connection, cancellationTokenSource, state));
             }
-
-            if (tuple == null)
-            {
-                return;
-            }
-
-            if (connection.State != WebSocketState.Open || tuple.Item2.IsCancellationRequested)
-            {
-                DisposeConnection(tuple);
-                return;
-            }
-
-            SendData(tuple);
         }
 
         protected void SendData(bool force)
         {
-            Tuple<IWebSocketConnection, CancellationTokenSource, Timer, TStateType>[] tuples;
+            Tuple<IWebSocketConnection, CancellationTokenSource, TStateType>[] tuples;
 
             lock (ActiveConnections)
             {
@@ -158,7 +117,7 @@ namespace MediaBrowser.Controller.Net
                     {
                         if (c.Item1.State == WebSocketState.Open && !c.Item2.IsCancellationRequested)
                         {
-                            var state = c.Item4;
+                            var state = c.Item3;
 
                             if (force || (DateTime.UtcNow - state.DateLastSendUtc).TotalMilliseconds >= state.IntervalMs)
                             {
@@ -177,17 +136,17 @@ namespace MediaBrowser.Controller.Net
             }
         }
 
-        private async void SendData(Tuple<IWebSocketConnection, CancellationTokenSource, Timer, TStateType> tuple)
+        private async void SendData(Tuple<IWebSocketConnection, CancellationTokenSource, TStateType> tuple)
         {
             var connection = tuple.Item1;
 
             try
             {
-                var state = tuple.Item4;
+                var state = tuple.Item3;
 
                 var cancellationToken = tuple.Item2.Token;
 
-                var data = await GetDataToSend(state, cancellationToken).ConfigureAwait(false);
+                var data = await GetDataToSend().ConfigureAwait(false);
 
                 if (data != null)
                 {
@@ -236,24 +195,11 @@ namespace MediaBrowser.Controller.Net
         /// Disposes the connection.
         /// </summary>
         /// <param name="connection">The connection.</param>
-        private void DisposeConnection(Tuple<IWebSocketConnection, CancellationTokenSource, Timer, TStateType> connection)
+        private void DisposeConnection(Tuple<IWebSocketConnection, CancellationTokenSource, TStateType> connection)
         {
             Logger.LogDebug("{1} stop transmitting over websocket to {0}", connection.Item1.RemoteEndPoint, GetType().Name);
 
             connection.Item1.Dispose();
-            var timer = connection.Item3;
-
-            if (timer != null)
-            {
-                try
-                {
-                    timer.Dispose();
-                }
-                catch (ObjectDisposedException)
-                {
-                    //TODO Investigate and properly fix.
-                }
-            }
 
             try
             {