Ignore failed send after close (WebSockets) (#593)

src/Microsoft.AspNetCore.Sockets.Http/Internal/SocketLoggerExtensions.cs

@@ -90,6 +90,9 @@ namespace Microsoft.AspNetCore.Sockets.Internal
         private static readonly Action<ILogger, DateTime, string, Exception> _errorWritingFrame =
             LoggerMessage.Define<DateTime, string>(LogLevel.Error, 11, "{time}: Connection Id {connectionId}: Error writing frame.");
 
+        private static readonly Action<ILogger, DateTime, string, Exception> _sendFailed =
+            LoggerMessage.Define<DateTime, string>(LogLevel.Trace, 12, "{time}: Connection Id {connectionId}: Socket failed to send.");
+
         // Category: ServerSentEventsTransport
         private static readonly Action<ILogger, DateTime, string, int, Exception> _sseWritingMessage =
             LoggerMessage.Define<DateTime, string, int>(LogLevel.Debug, 0, "{time}: Connection Id {connectionId}: Writing a {count} byte message.");
@@ -302,6 +305,14 @@ namespace Microsoft.AspNetCore.Sockets.Internal
             }
         }
 
+        public static void SendFailed(this ILogger logger, string connectionId, Exception ex)
+        {
+            if (logger.IsEnabled(LogLevel.Trace))
+            {
+                _sendFailed(logger, DateTime.Now, connectionId, ex);
+            }
+        }
+
         public static void SSEWritingMessage(this ILogger logger, string connectionId, int count)
         {
             if (logger.IsEnabled(LogLevel.Debug))

src/Microsoft.AspNetCore.Sockets.Http/Internal/Transports/WebSocketsTransport.cs

@@ -178,7 +178,16 @@ namespace Microsoft.AspNetCore.Sockets.Internal.Transports
                         {
                             _logger.SendPayload(_connectionId, buffer.Length);
 
-                            await ws.SendAsync(new ArraySegment<byte>(buffer), _options.WebSocketMessageType, endOfMessage: true, cancellationToken: CancellationToken.None);
+                            if (WebSocketCanSend(ws))
+                            {
+                                await ws.SendAsync(new ArraySegment<byte>(buffer), _options.WebSocketMessageType, endOfMessage: true, cancellationToken: CancellationToken.None);
+                            }
+                        }
+                        catch (WebSocketException socketException) when (!WebSocketCanSend(ws))
+                        {
+                            // this can happen when we send the CloseFrame to the client and try to write afterwards
+                            _logger.SendFailed(_connectionId, socketException);
+                            break;
                         }
                         catch (Exception ex)
                         {
@@ -189,5 +198,12 @@ namespace Microsoft.AspNetCore.Sockets.Internal.Transports
                 }
             }
         }
+
+        private static bool WebSocketCanSend(WebSocket ws)
+        {
+            return !(ws.State == WebSocketState.Aborted ||
+                   ws.State == WebSocketState.Closed ||
+                   ws.State == WebSocketState.CloseSent);
+        }
     }
 }

test/Microsoft.AspNetCore.Sockets.Tests/WebSocketsTests.cs

@@ -108,7 +108,7 @@ namespace Microsoft.AspNetCore.Sockets.Tests
             {
                 var options = new WebSocketOptions()
                 {
-                    CloseTimeout = TimeSpan.FromSeconds(1)
+                    CloseTimeout = TimeSpan.FromMilliseconds(100)
                 };
 
                 var ws = new WebSocketsTransport(options, transportSide, connectionId: string.Empty, loggerFactory: new LoggerFactory());