private async Task <IStreamQbservableProtocol> NegotiateClientAsync(Stream stream, IRemotingFormatter formatter, CancellationToken cancel)
{
Contract.Requires(stream != null);
Contract.Requires(formatter != null);
var id = (string)Id;
var protocol = StreamQbservableProtocolFactory.CreateClient(id, stream, formatter, cancel);
var buffer = Encoding.ASCII.GetBytes(id);
await protocol.SendAsync(BitConverter.GetBytes(id.Length), 0, 4).ConfigureAwait(false);
await protocol.SendAsync(buffer, 0, buffer.Length).ConfigureAwait(false);
await protocol.ReceiveAsync(buffer, 0, buffer.Length).ConfigureAwait(false);
Contract.Assume(Encoding.ASCII.GetString(buffer) == id);
return(protocol);
}
private static async Task <IStreamQbservableProtocol> NegotiateServerAsync(object baseId, Stream stream, IRemotingFormatter formatter, QbservableServiceOptions serviceOptions, CancellationToken cancel)
{
Contract.Requires(stream != null);
Contract.Requires(formatter != null);
Contract.Requires(serviceOptions != null);
var protocol = StreamQbservableProtocolFactory.CreateServer(stream, formatter, serviceOptions, cancel);
var lengthBuffer = new byte[4];
await protocol.ReceiveAsync(lengthBuffer, 0, 4).ConfigureAwait(false);
var length = BitConverter.ToInt32(lengthBuffer, 0);
if (length <= 0 || length > 255)
{
throw new InvalidOperationException("Invalid client ID received. (" + length + " bytes)");
}
var clientIdBuffer = new byte[length];
await protocol.ReceiveAsync(clientIdBuffer, 0, clientIdBuffer.Length).ConfigureAwait(false);
var clientId = Encoding.ASCII.GetString(clientIdBuffer);
if (clientId == null || string.IsNullOrWhiteSpace(clientId))
{
throw new InvalidOperationException("Invalid client ID received (empty or only whitespace).");
}
await protocol.SendAsync(clientIdBuffer, 0, clientIdBuffer.Length).ConfigureAwait(false);
protocol.ClientId = baseId + " (" + clientId + ")";
return(protocol);
}