// Does all the real work of making a connection. Currently, this blocks on the initial connection.
// I'd rather there be a cleaner interface for this, where the Task itself is being polled and the state changes over when it's done.
private async Task DoConnection()
{
if (_status != Status.ReadyToConnect)
{
throw new Exception("Not in status=ReadyToConnect.");
}
_lastErrorMsg = string.Empty;
Uri uri = new Uri(_connectUrl); // I think this can throw exceptions for bad formatting?
// Creates a websocket connection and lets you start sending or receiving messages on separate threads.
ClientWebSocket wsClient = null;
try
{
wsClient = new ClientWebSocket();
using (CancellationTokenSource connectTimeout = new CancellationTokenSource(_connectTimeoutMS))
{
// Apply all the headers that were passed in.
foreach (KeyValuePair <string, string> kvp in _connectHeaders)
{
wsClient.Options.SetRequestHeader(kvp.Key, kvp.Value);
}
_status = Status.Connecting;
await wsClient.ConnectAsync(uri, connectTimeout.Token).ConfigureAwait(false);
}
_status = Status.Connected;
_rgws = new RGWebSocket(OnRecvTextMsg, OnRecvBinaryMsg, OnDisconnect, _logCb, uri.ToString(), wsClient);
_logCb?.Invoke($"UWS Connected to {_connectUrl}", 1);
}
catch (AggregateException age)
{
if (age.InnerException is OperationCanceledException)
{
_lastErrorMsg = "Connection timed out.";
_logCb?.Invoke(_lastErrorMsg, 0);
}
else if (age.InnerException is WebSocketException)
{
_lastErrorMsg = ((WebSocketException)age.InnerException).Message;
_logCb?.Invoke(_lastErrorMsg, 0);
}
else
{
_lastErrorMsg = age.Message;
_logCb?.Invoke(_lastErrorMsg, 0);
}
wsClient?.Dispose(); // cleanup
_status = Status.Disconnected;
}
catch (Exception e)
{
_lastErrorMsg = e.Message;
_logCb?.Invoke(_lastErrorMsg, 0);
wsClient?.Dispose(); // cleanup
_status = Status.Disconnected;
}
}
//-------------------
// Privates. These calls occur on non-main-threads, so messages get queued up and you POLL them out in the Receive call above on the main thread.
private Task OnReceiveText(RGWebSocket rgws, string msg)
{
_incomingMessages.Add(new wsMessage()
{
stringMsg = msg, binMsg = null
});
_logger($"UWS Recv {msg.Length} bytes txt", 3);
return(Task.CompletedTask);
}
// This callback holds the reference to PooledArray, so it must be decremented to free it (eventually) after it's consumed.
private Task OnReceiveBinary(RGWebSocket rgws, PooledArray msg)
{
msg.IncRef(); // bump the refcount since we aren't done with it yet, and RGWebSocket can decrement it without freeing the buffer
_incomingMessages.Add(new wsMessage()
{
stringMsg = string.Empty, binMsg = msg
});
_logger($"UWS Recv {msg.Length} bytes bin", 3);
return(Task.CompletedTask);
}
// We capture the callback so we can manage the websocket set internally.
private void OnDisconnection(RGWebSocket rgws)
{
RGWebSocket ws;
if (_websockets.TryRemove(rgws._uniqueId, out ws))
{
_disconnected.TryAdd(rgws._uniqueId, rgws);
_disconnectionCount.Release();
_onDisconnect(rgws); // let the caller know it's disconnected now
}
}
// A simple blocking way to make sure this is all torn down.
public void Shutdown()
{
if (_rgws != null)
{
_rgws.Shutdown();
_rgws.Dispose();
_rgws = null;
}
_logger("UWS shutdown.", 1);
_status = Status.ReadyToConnect;
}
// Add this websocket to the list of those we need to remove and unblock the cleanup thread
private void OnDisconnection(RGWebSocket rgws)
{
_logger($"{rgws._displayId} OnDisconnection call.", 3);
_disconnected.Add(rgws); // finally, put it on the list of things to be disposed of
_cleanupSocket.Set(); // Let the Cleanup process know there's something to do
}
//-------------------
// Task: when a connection is requested, depending on whether it's an HTTP request or WebSocket request, do different things.
private async Task HandleConnection(HttpListenerContext httpContext)
{
// Allow debugging to actually happen, where you have unlimited time to check things without breaking a connection. -1 means don't cancel over time.
int timeoutMS = Debugger.IsAttached ? -1 : _connectionMS;
if (httpContext.Request.IsWebSocketRequest)
{
// Kick off an async task to upgrade the web socket and do send/recv messaging, but fail if it takes more than a second to finish.
try
{
_logger("WebSocketServer.HandleConnection - websocket detected. Upgrading connection.", 2);
using (CancellationTokenSource upgradeTimeout = new CancellationTokenSource(timeoutMS))
{
HttpListenerWebSocketContext webSocketContext = await Task.Run(async() => { return(await httpContext.AcceptWebSocketAsync(null, _idleSeconds).ConfigureAwait(false)); }, upgradeTimeout.Token);
_logger("WebSocketServer.HandleConnection - websocket detected. Upgraded.", 3);
// Note, we hook our own OnDisconnect before proxying it on to the ConnectionManager. Note, due to heavy congestion and C# scheduling, it's entirely possible that this is already a closed socket, and is immediately flagged for destruction.
RGWebSocket rgws = new RGWebSocket(httpContext, _connectionManager.OnReceiveText, _connectionManager.OnReceiveBinary, OnDisconnection, _logger, httpContext.Request.RemoteEndPoint.ToString(), webSocketContext.WebSocket);
_websockets.TryAdd(rgws._uniqueId, rgws);
await _connectionManager.OnConnection(rgws).ConfigureAwait(false);
_logger($"WebSocketServer.HandleConnection - websocket detected. Upgrade completed. {rgws._displayId}", 3);
}
}
catch (OperationCanceledException ex) // timeout
{
_logger($"WebSocketServer.HandleConnection - websocket upgrade timeout {ex.Message}", 0);
httpContext.Response.StatusCode = 500;
httpContext.Response.Close(); // this breaks the connection, otherwise it may linger forever
}
catch (Exception ex) // anything else
{
_logger($"WebSocketServer.HandleConnection - websocket upgrade exception {ex.Message}", 0);
httpContext.Response.StatusCode = 500;
httpContext.Response.Close(); // this breaks the connection, otherwise it may linger forever
}
}
else // let the application specify what the HTTP response is, but we do the async write here to free up the app to do other things
{
try
{
_logger($"WebSocketServer.HandleConnection - normal http request {httpContext.Request.RawUrl}", 3);
using (CancellationTokenSource responseTimeout = new CancellationTokenSource(timeoutMS))
{
// Remember to set httpContext.Response.StatusCode, httpContext.Response.ContentLength64, and httpContenxtResponse.OutputStream
await _httpRequestCallback(httpContext).ConfigureAwait(false);
}
}
catch (OperationCanceledException ex) // timeout
{
_logger($"WebSocketServer.HandleConnection - websocket upgrade timeout {ex.Message}", 0);
httpContext.Response.StatusCode = 500;
// httpContext.Response.Abort(); // this breaks the connection, otherwise it may linger forever
}
catch (Exception ex) // anything else
{
_logger($"WebSocketServer.HandleConnection - http callback handler exception {ex.Message}", 0);
httpContext.Response.StatusCode = 500;
// httpContext.Response.Abort(); // this breaks the connection, otherwise it may linger forever
}
finally
{
httpContext.Response.Close(); // This frees all the memory associated with this connection.
}
}
}
// Forcibly disposes the RGWS
public void Dispose()
{
_rgws?.Dispose();
_rgws = null;
}
// At this point, it's a done deal. Both Recv and Send are completed, nothing to synchronize. This is called by Send after Recv is finished.
private void OnDisconnect(RGWebSocket rgws)
{
_logCb?.Invoke("UWS Disconnected.", 1);
_status = Status.Disconnected;
}
private void OnRecvBinaryMsg(RGWebSocket rgws, byte[] msg)
{
_incomingMessages.Enqueue(new Tuple <string, byte[]>(string.Empty, msg));
_logCb?.Invoke($"UWS Recv {msg.Length} bytes bin", 2);
}
//-------------------
// Privates. These calls occur on non-main-threads, so messages get queued up and you POLL them out in the Receive call above on the main thread.
private void OnRecvTextMsg(RGWebSocket rgws, string msg)
{
_incomingMessages.Enqueue(new Tuple <string, byte[]>(msg, null));
_logCb?.Invoke($"UWS Recv {msg.Length} bytes txt", 2);
}
//-------------------
// Task: when a connection is requested, depending on whether it's an HTTP request or WebSocket request, do different things.
private async Task HandleConnection(Task <HttpListenerContext> listenerContext)
{
HttpListenerContext httpContext = listenerContext.Result;
if (httpContext.Request.IsWebSocketRequest)
{
// Kick off an async task to upgrade the web socket and do send/recv messaging, but fail if it takes more than a second to finish.
try
{
_logger?.Invoke("WebSocketServer.HandleConnection - websocket detected. Upgrading connection.", 1);
using (CancellationTokenSource upgradeTimeout = new CancellationTokenSource(_connectionMS))
{
HttpListenerWebSocketContext webSocketContext = await Task.Run(async() => { return(await httpContext.AcceptWebSocketAsync(null).ConfigureAwait(false)); }, upgradeTimeout.Token);
_logger?.Invoke("WebSocketServer.HandleConnection - websocket detected. Upgraded.", 1);
RGWebSocket rgws = new RGWebSocket(_onReceiveMsgText, _onReceiveMsgBinary, OnDisconnection, _logger, httpContext.Request.RemoteEndPoint.ToString(), webSocketContext.WebSocket, 25);
_websockets.TryAdd(rgws._uniqueId, rgws);
_websocketConnection(rgws);
}
}
catch (OperationCanceledException) // timeout
{
_logger?.Invoke("WebSocketServer.HandleConnection - websocket upgrade timeout", 1);
httpContext.Response.StatusCode = 500;
httpContext.Response.Close();
}
catch // anything else
{
_logger?.Invoke("WebSocketServer.HandleConnection - websocket upgrade exception", 1);
httpContext.Response.StatusCode = 500;
httpContext.Response.Close();
}
}
else // let the application specify what the HTTP response is, but we do the async write here to free up the app to do other things
{
try
{
_logger?.Invoke("WebSocketServer.HandleConnection - normal http request", 1);
using (CancellationTokenSource responseTimeout = new CancellationTokenSource(_connectionMS))
{
byte[] buffer = null;
httpContext.Response.StatusCode = _httpRequestCallback(httpContext, out buffer);
httpContext.Response.ContentLength64 = buffer.Length;
await httpContext.Response.OutputStream.WriteAsync(buffer, 0, buffer.Length, responseTimeout.Token);
}
}
catch (OperationCanceledException) // timeout
{
_logger?.Invoke("WebSocketServer.HandleConnection - http response timeout", 1);
httpContext.Response.StatusCode = 500;
}
catch // anything else
{
_logger?.Invoke("WebSocketServer.HandleConnection - http callback handler exception", 1);
httpContext.Response.StatusCode = 500;
}
finally
{
httpContext.Response.Close();
}
}
}
// At this point, it's a done deal. Both Recv and Send are completed, nothing to synchronize. This is called at the bottom of the Send thread after Recv is completed.
// However, it is possible that the Recv/Send threads shutdown before the RGWS constructor is even finished
private void OnDisconnect(RGWebSocket rgws)
{
_logger("UWS Disconnected.", 1);
_status = Status.Disconnected;
_disconnectCallback?.Invoke(this); // This callback needs to NOT modify any tracking structures, because it may be called as early as DURING the RGWS constructor. Just set flags
}