Optionally disconnect SWT clients that aren't receiving messages

Assets/Mirror/Transports/SimpleWeb/SimpleWeb/Server/SimpleWebServer.cs

@@ -17,13 +17,13 @@ public class SimpleWebServer
 
         public bool Active { get; private set; }
 
-        public SimpleWebServer(int maxMessagesPerTick, TcpConfig tcpConfig, int maxMessageSize, int handshakeMaxSize, SslConfig sslConfig)
+        public SimpleWebServer(int maxMessagesPerTick, TcpConfig tcpConfig, int maxMessageSize, int handshakeMaxSize, SslConfig sslConfig, int sendQueueMaxMessageCount)
         {
             this.maxMessagesPerTick = maxMessagesPerTick;
             // use max because bufferpool is used for both messages and handshake
             int max = Math.Max(maxMessageSize, handshakeMaxSize);
             bufferPool = new BufferPool(5, 20, max);
-            server = new WebSocketServer(tcpConfig, maxMessageSize, handshakeMaxSize, sslConfig, bufferPool);
+            server = new WebSocketServer(tcpConfig, maxMessageSize, handshakeMaxSize, sslConfig, bufferPool, sendQueueMaxMessageCount);
         }
 
         public void Start(ushort port)

Assets/Mirror/Transports/SimpleWeb/SimpleWeb/Server/WebSocketServer.cs

@@ -12,6 +12,7 @@ public class WebSocketServer
 
         readonly TcpConfig tcpConfig;
         readonly int maxMessageSize;
+        readonly int sendQueueMaxMessageCount;
 
         TcpListener listener;
         Thread acceptThread;
@@ -23,10 +24,11 @@ public class WebSocketServer
 
         int _idCounter = 0;
 
-        public WebSocketServer(TcpConfig tcpConfig, int maxMessageSize, int handshakeMaxSize, SslConfig sslConfig, BufferPool bufferPool)
+        public WebSocketServer(TcpConfig tcpConfig, int maxMessageSize, int handshakeMaxSize, SslConfig sslConfig, BufferPool bufferPool, int sendQueueMaxMessageCount)
         {
             this.tcpConfig = tcpConfig;
             this.maxMessageSize = maxMessageSize;
+            this.sendQueueMaxMessageCount = sendQueueMaxMessageCount;
             sslHelper = new ServerSslHelper(sslConfig);
             this.bufferPool = bufferPool;
             handShake = new ServerHandshake(this.bufferPool, handshakeMaxSize);
@@ -187,6 +189,13 @@ public void Send(int id, ArrayBuffer buffer)
         {
             if (connections.TryGetValue(id, out Connection conn))
             {
+                if (sendQueueMaxMessageCount > 0 && conn.sendQueue.Count + 1 >= sendQueueMaxMessageCount)
+                {
+                    Log.Warn("[SWT-WebSocketServer]: Send: cannot send message to {0} because its send queue has reached max count. Disconnecting connection", id);
+                    conn.Dispose();
+                    return;
+                }
+
                 conn.sendQueue.Enqueue(buffer);
                 conn.sendPending.Set();
             }

Assets/Mirror/Transports/SimpleWeb/SimpleWebTransport.cs

@@ -89,6 +89,10 @@ public ushort Port
             "If WaitBeforeSend is true then BatchSend Will also be set to true")]
         public bool waitBeforeSend = true;
 
+        [Tooltip("Disconnects clients if their sendQueue Count reaches this value. Disabled if <= 0.\n" +
+            "Prevents hundreds of buffers being allocated and pooled forever if the client stops processing incoming messages without disconnecting")]
+        public int sendQueueMaxMessageCount = 0;
+
         [Header("Client settings")]
 
         [Tooltip("Sets connect scheme to wss. Useful when client needs to connect using wss when TLS is outside of transport.\nNOTE: if sslEnabled is true clientUseWss is also true")]
@@ -293,7 +297,7 @@ public override void ServerStart()
                 Log.Warn("[SWT-ServerStart]: Server Already Started");
 
             SslConfig config = SslConfigLoader.Load(sslEnabled, sslCertJson, sslProtocols);
-            server = new SimpleWebServer(serverMaxMsgsPerTick, TcpConfig, maxMessageSize, maxHandshakeSize, config);
+            server = new SimpleWebServer(serverMaxMsgsPerTick, TcpConfig, maxMessageSize, maxHandshakeSize, config, sendQueueMaxMessageCount);
 
             server.onConnect += OnServerConnectedWithAddress.Invoke;
             server.onDisconnect += OnServerDisconnected.Invoke;