internal static async ValueTask Write(ConnectionContext connection, GrainId grainId, NetworkProtocolVersion protocolVersion, SiloAddress siloAddress)
{
var output = connection.Transport.Output;
var outputWriter = new PrefixingBufferWriter <byte, PipeWriter>(output, sizeof(int), 1024, MemoryPool <byte> .Shared);
var writer = new BinaryTokenStreamWriter2 <PrefixingBufferWriter <byte, PipeWriter> >(outputWriter);
writer.Write(grainId);
writer.Write((byte)protocolVersion);
if (siloAddress is null)
{
writer.WriteNull();
}
else
{
writer.Write((byte)SerializationTokenType.SiloAddress);
writer.Write(siloAddress);
}
writer.Commit();
var length = outputWriter.CommittedBytes;
if (length > MaxPreambleLength)
{
throw new InvalidOperationException($"Created preamble of length {length}, which is greater than maximum allowed size of {MaxPreambleLength}.");
}
WriteLength(outputWriter, length);
var flushResult = await output.FlushAsync();
if (flushResult.IsCanceled)
{
throw new OperationCanceledException("Flush canceled");
}
return;
}
protected override async Task RunInternal()
{
Exception error = default;
try
{
if (this.connectionOptions.ProtocolVersion == NetworkProtocolVersion.Version1)
{
// This version of the protocol does not support symmetric preamble, so either send or receive preamble depending on
// Whether or not this is an inbound or outbound connection.
if (this.RemoteSiloAddress is null)
{
// Inbound connection
var protocolVersion = await ReadPreamble();
// To support graceful transition to higher protocol versions, send a preamble if the remote endpoint supports it.
if (protocolVersion >= NetworkProtocolVersion.Version2)
{
await WritePreamble();
}
}
else
{
// Outbound connection
await WritePreamble();
}
}
else
{
// Later versions of the protocol send and receive preamble at both ends of the connection.
if (this.RemoteSiloAddress is null)
{
// Inbound connection
var protocolVersion = await ReadPreamble();
// To support graceful transition from lower protocol versions, only send a preamble if the remote endpoint supports it.
if (protocolVersion >= NetworkProtocolVersion.Version2)
{
await WritePreamble();
}
}
else
{
// Outbound connection
await Task.WhenAll(ReadPreamble().AsTask(), WritePreamble());
}
}
this.MessageReceivedCounter = MessagingStatisticsGroup.GetMessageReceivedCounter(this.RemoteSiloAddress);
this.MessageSentCounter = MessagingStatisticsGroup.GetMessageSendCounter(this.RemoteSiloAddress);
await base.RunInternal();
}
catch (Exception exception) when((error = exception) is null)
{
Debug.Fail("Execution should not be able to reach this point.");
}
finally
{
if (!(this.RemoteSiloAddress is null))
{
this.connectionManager.OnConnectionTerminated(this.RemoteSiloAddress, this, error);
}
}
async Task WritePreamble()
{
await ConnectionPreamble.Write(
this.Context,
Constants.SiloDirectConnectionId,
this.connectionOptions.ProtocolVersion,
this.LocalSiloAddress);
}
async ValueTask <NetworkProtocolVersion> ReadPreamble()
{
var(grainId, protocolVersion, siloAddress) = await ConnectionPreamble.Read(this.Context);
if (!grainId.Equals(Constants.SiloDirectConnectionId))
{
throw new InvalidOperationException("Unexpected non-proxied connection on silo endpoint.");
}
if (siloAddress is object)
{
this.RemoteSiloAddress = siloAddress;
this.connectionManager.OnConnected(siloAddress, this);
}
this.RemoteProtocolVersion = protocolVersion;
return(protocolVersion);
}
}
