/// <summary>
/// Performs the session negotiation and authentication
/// </summary>
/// <param name="channel"></param>
/// <param name="compressionSelector"></param>
/// <param name="encryptionSelector"></param>
/// <param name="identity"></param>
/// <param name="authenticator"></param>
/// <param name="instance"></param>
/// <param name="cancellationToken"></param>
/// <returns></returns>
public async static Task <Session> EstablishSessionAsync(this IClientChannel channel, Func <SessionCompression[], SessionCompression> compressionSelector,
Func <SessionEncryption[], SessionEncryption> encryptionSelector, Identity identity, Func <AuthenticationScheme[], Authentication, Authentication> authenticator,
string instance, CancellationToken cancellationToken)
{
if (channel == null)
{
throw new ArgumentNullException("channel");
}
if (authenticator == null)
{
throw new ArgumentNullException("authenticator");
}
var receivedSession = await channel.StartNewSessionAsync(cancellationToken).ConfigureAwait(false);
// Session negotiation
if (receivedSession.State == SessionState.Negotiating)
{
if (compressionSelector == null)
{
throw new ArgumentNullException("compressionSelector");
}
if (encryptionSelector == null)
{
throw new ArgumentNullException("encryptionSelector");
}
// Select options
receivedSession = await channel.NegotiateSessionAsync(
compressionSelector(receivedSession.CompressionOptions),
encryptionSelector(receivedSession.EncryptionOptions),
cancellationToken).ConfigureAwait(false);
if (receivedSession.State == SessionState.Negotiating)
{
// Configure transport
if (receivedSession.Compression != channel.Transport.Compression)
{
await channel.Transport.SetCompressionAsync(receivedSession.Compression.Value, cancellationToken).ConfigureAwait(false);
}
if (receivedSession.Encryption != channel.Transport.Encryption)
{
await channel.Transport.SetEncryptionAsync(receivedSession.Encryption.Value, cancellationToken).ConfigureAwait(false);
}
}
// Await for authentication options
receivedSession = await channel.ReceiveAuthenticatingSessionAsync(cancellationToken).ConfigureAwait(false);
}
// Session authentication
if (receivedSession.State == SessionState.Authenticating)
{
do
{
Authentication roundtrip = null;
receivedSession = await channel.AuthenticateSessionAsync(
identity,
authenticator(receivedSession.SchemeOptions, roundtrip),
instance,
cancellationToken).ConfigureAwait(false);
roundtrip = receivedSession.Authentication;
} while (receivedSession.State == SessionState.Authenticating);
}
return(receivedSession);
}