internal static async Task <HttpListenerWebSocketContext> AcceptWebSocketAsyncCore(HttpListenerContext context,
string subProtocol,
int receiveBufferSize,
TimeSpan keepAliveInterval,
ArraySegment <byte>?internalBuffer = null)
{
ValidateOptions(subProtocol, receiveBufferSize, MinSendBufferSize, keepAliveInterval);
// get property will create a new response if one doesn't exist.
HttpListenerResponse response = context.Response;
HttpListenerRequest request = context.Request;
ValidateWebSocketHeaders(context);
string secWebSocketVersion = request.Headers[HttpKnownHeaderNames.SecWebSocketVersion];
// Optional for non-browser client
string origin = request.Headers[HttpKnownHeaderNames.Origin];
string[] secWebSocketProtocols = null;
string outgoingSecWebSocketProtocolString;
bool shouldSendSecWebSocketProtocolHeader =
ProcessWebSocketProtocolHeader(
request.Headers[HttpKnownHeaderNames.SecWebSocketProtocol],
subProtocol,
out outgoingSecWebSocketProtocolString);
if (shouldSendSecWebSocketProtocolHeader)
{
secWebSocketProtocols = new string[] { outgoingSecWebSocketProtocolString };
response.Headers.Add(HttpKnownHeaderNames.SecWebSocketProtocol, outgoingSecWebSocketProtocolString);
}
// negotiate the websocket key return value
string secWebSocketKey = request.Headers[HttpKnownHeaderNames.SecWebSocketKey];
string secWebSocketAccept = HttpWebSocket.GetSecWebSocketAcceptString(secWebSocketKey);
response.Headers.Add(HttpKnownHeaderNames.Connection, HttpKnownHeaderNames.Upgrade);
response.Headers.Add(HttpKnownHeaderNames.Upgrade, WebSocketUpgradeToken);
response.Headers.Add(HttpKnownHeaderNames.SecWebSocketAccept, secWebSocketAccept);
response.StatusCode = (int)HttpStatusCode.SwitchingProtocols; // HTTP 101
response.StatusDescription = HttpStatusDescription.Get(HttpStatusCode.SwitchingProtocols);
HttpResponseStream responseStream = response.OutputStream as HttpResponseStream;
// Send websocket handshake headers
await responseStream.WriteWebSocketHandshakeHeadersAsync().ConfigureAwait(false);
WebSocket webSocket = WebSocket.CreateFromStream(context.Connection.ConnectedStream, isServer: true, subProtocol, keepAliveInterval);
HttpListenerWebSocketContext webSocketContext = new HttpListenerWebSocketContext(
request.Url,
request.Headers,
request.Cookies,
context.User,
request.IsAuthenticated,
request.IsLocal,
request.IsSecureConnection,
origin,
secWebSocketProtocols != null ? secWebSocketProtocols : Array.Empty <string>(),
secWebSocketVersion,
secWebSocketKey,
webSocket);
return(webSocketContext);
}
