Fleck

Fleck is a WebSocket server implementation in C#. Branched from the Nugget project, Fleck requires no inheritance, container, or additional references.

Example

The following is an example that will echo to a client.

var server = new WebSocketServer("ws://0.0.0.0:8181");
server.Start(socket =>
{
  socket.OnOpen = () => Console.WriteLine("Open!");
  socket.OnClose = () => Console.WriteLine("Close!");
  socket.OnMessage = message => socket.Send(message);
});
        

Supported WebSocket Versions

Fleck supports several WebSocket versions of modern web browsers

• Hixie-Draft-76/Hybi-00 (Safari 5, Chrome < 14, Firefox 4 (when enabled))
• Hybi-07 (Firefox 6)
• Hybi-10 (Chrome 14-16, Firefox 7)
• Hybi-13 (Chrome 17+)

Secure WebSockets (wss://)

Enabling secure connections requires two things: using the scheme wss instead of ws, and pointing Fleck to an x509 certificate containing a public and private key

var server = new WebSocketServer("wss://0.0.0.0:8431");
server.Certificate = new X509Certificate2("MyCert.pfx");
server.Start(socket =>
{
  //...use as normal
});

SubProtocol Negotiation

To enable negotiation of subprotocols, specify the supported protocols on the WebSocketServer.SupportedSubProtocols property. The negotiated subprotocol will be available on the socket's ConnectionInfo.NegotiatedSubProtocol.

If no supported subprotocols are found on the client request (the Sec-WebSocket-Protocol header), the connection will be closed.

var server = new WebSocketServer("ws://0.0.0.0:8181");
server.SupportedSubProtocols = new []{ "superchat", "chat" };
server.Start(socket =>
{
  //socket.ConnectionInfo.NegotiatedSubProtocol is populated
});

Custom Logging

Fleck can log into Log4Net or any other third party logging system. Just override the FleckLog.LogAction property with the desired behavior.

ILog logger = LogManager.GetLogger(typeof(FleckLog));

FleckLog.LogAction = (level, message, ex) => {
  switch(level) {
    case LogLevel.Debug:
      logger.Debug(message, ex);
      break;
    case LogLevel.Error:
      logger.Error(message, ex);
      break;
    case LogLevel.Warn:
      logger.Warn(message, ex);
      break;
    default:
      logger.Info(message, ex);
      break;
  }
};

Disable Nagle's Algorithm

Set NoDelay to true on the WebSocketConnection.ListenerSocket

var server = new WebSocketServer("ws://0.0.0.0:8181");
server.ListenerSocket.NoDelay = true;
server.Start(socket =>
{
  //Child connections will not use Nagle's Algorithm
});

Auto Restart After Listen Error

Set RestartAfterListenError to true on the WebSocketConnection

var server = new WebSocketServer("ws://0.0.0.0:8181");
server.RestartAfterListenError = true;
server.Start(socket =>
{
  //...use as normal
});

License

The MIT License

Copyright (c) 2010-2016 Jason Staten

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.