/// <summary>
/// Are about to send a new message
/// </summary>
/// <param name="message">Message to send</param>
/// <remarks>
/// Can be used to prepare the next message. for instance serialize it etc.
/// </remarks>
/// <exception cref="NotSupportedException">Message is of a type that the encoder cannot handle.</exception>
public void Prepare(object message)
{
if (message is IWebSocketMessage)
{
_message = (IWebSocketMessage)message;
_message.Payload.Position = 0;
_totalAmountToSend = (int)_message.Payload.Length;
}
else
{
try
{
_httpMessageEncoder.Prepare(message);
var httpMessage = message as IHttpMessage;
if (WebSocketUtils.IsWebSocketUpgrade(httpMessage))
{
_handshake = httpMessage;
}
}
catch (Exception e)
{
throw new InvalidOperationException("This encoder only supports messages deriving from 'HttpMessage' or 'WebSocketMessage'", e);
}
}
}
/// <summary>
/// Intercept http messages and look for websocket upgrade requests
/// </summary>
/// <param name="message">message from http decoder</param>
private void OnHttpMessage(object message)
{
var httpMessage = message as IHttpMessage;
// TODO: is there a better way to detect WebSocket upgrade?
if (WebSocketUtils.IsWebSocketUpgrade(httpMessage))
{
_handshake = httpMessage;
_isWebSocket = true;
}
_messageReceived(message);
}
/// <summary>
/// Handles the upgrade
/// </summary>
/// <param name="source">Channel that we've received a request from</param>
/// <param name="msg">Message received.</param>
protected override void OnMessage(ITcpChannel source, object msg)
{
var httpMessage = msg as IHttpMessage;
if (WebSocketUtils.IsWebSocketUpgrade(httpMessage))
{
if (httpMessage is IHttpRequest) // server mode
{
var args = new WebSocketClientConnectEventArgs(source, (IHttpRequest)httpMessage);
WebSocketClientConnect(this, args);
if (args.MayConnect)
{
var webSocketKey = httpMessage.Headers["Sec-WebSocket-Key"];
// TODO: why not provide the response in the WebSocketClientConnectEventArgs event?
var response = new WebSocketUpgradeResponse(webSocketKey);
source.Send(response);
WebSocketClientConnected(this,
new WebSocketClientConnectedEventArgs(source, (IHttpRequest)httpMessage, response));
}
else
{
var response = new HttpResponseBase(HttpStatusCode.NotImplemented, "Not Implemented", "HTTP/1.1");
if (args.Response != null)
{
response.Body = args.Response;
}
source.Send(response);
}
return;
}
if (httpMessage is IHttpResponse) // client mode
{
WebSocketClientConnected(this,
new WebSocketClientConnectedEventArgs(source, null, (IHttpResponse)httpMessage));
}
}
var webSocketMessage = msg as IWebSocketMessage;
if (webSocketMessage != null)
{
// standard message responses handled by listener
switch (webSocketMessage.Opcode)
{
case WebSocketOpcode.Ping:
source.Send(new WebSocketMessage(WebSocketOpcode.Pong, webSocketMessage.Payload));
return;
case WebSocketOpcode.Close:
source.Send(new WebSocketMessage(WebSocketOpcode.Close));
source.Close();
WebSocketClientDisconnected(this,
new ClientDisconnectedEventArgs(source, new Exception("WebSocket closed")));
return;
}
_webSocketMessageReceived(source, webSocketMessage);
return;
}
base.OnMessage(source, msg);
}
