private async Task readMessageAsync(string endpoint, Stream stream,
Func <Message[], IMessageAcceptance> acceptMessages)
{
bool serializationErrorOccurred = false;
Message[] messages = null;
try
{
var length = await new ReadLength(Logger, endpoint).GetAsync(stream).ConfigureAwait(false);
messages = await new ReadMessage(Logger, length, endpoint).GetAsync(stream).ConfigureAwait(false);
}
catch (SerializationException exception)
{
Logger.Info("Unable to deserialize messages", exception);
serializationErrorOccurred = true;
}
if (serializationErrorOccurred)
{
await new WriteSerializationError(Logger).ProcessAsync(stream).ConfigureAwait(false);
}
IMessageAcceptance acceptance = null;
byte[] errorBytes = null;
try
{
acceptance = acceptMessages(messages);
Logger.Debug("All messages from {0} were accepted", endpoint);
}
catch (QueueDoesNotExistsException)
{
Logger.Info("Failed to accept messages from {0} because queue does not exists", endpoint);
errorBytes = ProtocolConstants.QueueDoesNoExiststBuffer;
}
catch (Exception exception)
{
errorBytes = ProtocolConstants.ProcessingFailureBuffer;
Logger.Info("Failed to accept messages from " + endpoint, exception);
}
if (errorBytes != null)
{
await new WriteProcessingError(Logger, errorBytes, endpoint).ProcessAsync(stream).ConfigureAwait(false);
return;
}
try
{
await new WriteReceived(Logger, endpoint).ProcessAsync(stream).ConfigureAwait(false);
}
catch (Exception)
{
acceptance.Abort();
return;
}
try
{
await new ReadAcknowledgement(Logger, endpoint).ProcessAsync(stream).ConfigureAwait(false);
}
catch (Exception)
{
acceptance.Abort();
return;
}
bool commitSuccessful;
try
{
acceptance.Commit();
commitSuccessful = true;
}
catch (Exception exception)
{
Logger.Info("Unable to commit messages from " + endpoint, exception);
commitSuccessful = false;
}
if (commitSuccessful == false)
{
await new WriteRevert(Logger, endpoint).ProcessAsync(stream).ConfigureAwait(false);
}
}
private IEnumerator <int> ProcessRequest(TcpClient client, AsyncEnumerator ae)
{
try
{
using (client)
using (var stream = client.GetStream())
{
var sender = client.Client.RemoteEndPoint;
var lenOfDataToReadBuffer = new byte[sizeof(int)];
var lenEnumerator = new AsyncEnumerator(ae.ToString());
try
{
lenEnumerator.BeginExecute(
StreamUtil.ReadBytes(lenOfDataToReadBuffer, stream, lenEnumerator, "length data", false), ae.End());
}
catch (Exception exception)
{
logger.Warn("Unable to read length data from " + sender, exception);
yield break;
}
yield return(1);
try
{
lenEnumerator.EndExecute(ae.DequeueAsyncResult());
}
catch (Exception exception)
{
logger.Warn("Unable to read length data from " + sender, exception);
yield break;
}
var lengthOfDataToRead = BitConverter.ToInt32(lenOfDataToReadBuffer, 0);
if (lengthOfDataToRead < 0)
{
logger.WarnFormat("Got invalid length {0} from sender {1}", lengthOfDataToRead, sender);
yield break;
}
logger.DebugFormat("Reading {0} bytes from {1}", lengthOfDataToRead, sender);
var buffer = new byte[lengthOfDataToRead];
var readBufferEnumerator = new AsyncEnumerator(ae.ToString());
try
{
readBufferEnumerator.BeginExecute(
StreamUtil.ReadBytes(buffer, stream, readBufferEnumerator, "message data", false), ae.End());
}
catch (Exception exception)
{
logger.Warn("Unable to read message data from " + sender, exception);
yield break;
}
yield return(1);
try
{
readBufferEnumerator.EndExecute(ae.DequeueAsyncResult());
}
catch (Exception exception)
{
logger.Warn("Unable to read message data from " + sender, exception);
yield break;
}
Message[] messages = null;
try
{
messages = SerializationExtensions.ToMessages(buffer);
logger.DebugFormat("Deserialized {0} messages from {1}", messages.Length, sender);
}
catch (Exception exception)
{
logger.Warn("Failed to deserialize messages from " + sender, exception);
}
if (messages == null)
{
try
{
stream.BeginWrite(ProtocolConstants.SerializationFailureBuffer, 0,
ProtocolConstants.SerializationFailureBuffer.Length, ae.End(), null);
}
catch (Exception exception)
{
logger.Warn("Unable to send serialization format error to " + sender, exception);
yield break;
}
yield return(1);
try
{
stream.EndWrite(ae.DequeueAsyncResult());
}
catch (Exception exception)
{
logger.Warn("Unable to send serialization format error to " + sender, exception);
}
yield break;
}
IMessageAcceptance acceptance = null;
byte[] errorBytes = null;
try
{
acceptance = acceptMessages(messages);
logger.DebugFormat("All messages from {0} were accepted", sender);
}
catch (QueueDoesNotExistsException)
{
logger.WarnFormat("Failed to accept messages from {0} because queue does not exists", sender);
errorBytes = ProtocolConstants.QueueDoesNoExiststBuffer;
}
catch (Exception exception)
{
errorBytes = ProtocolConstants.ProcessingFailureBuffer;
logger.Warn("Failed to accept messages from " + sender, exception);
}
if (errorBytes != null)
{
try
{
stream.BeginWrite(errorBytes, 0,
errorBytes.Length, ae.End(), null);
}
catch (Exception exception)
{
logger.Warn("Unable to send processing failure from " + sender, exception);
yield break;
}
yield return(1);
try
{
stream.EndWrite(ae.DequeueAsyncResult());
}
catch (Exception exception)
{
logger.Warn("Unable to send processing failure from " + sender, exception);
}
yield break;
}
logger.DebugFormat("Sending reciept notice to {0}", sender);
try
{
stream.BeginWrite(ProtocolConstants.RecievedBuffer, 0, ProtocolConstants.RecievedBuffer.Length,
ae.End(), null);
}
catch (Exception exception)
{
logger.Warn("Could not send reciept notice to " + sender, exception);
acceptance.Abort();
yield break;
}
yield return(1);
try
{
stream.EndWrite(ae.DequeueAsyncResult());
}
catch (Exception exception)
{
logger.Warn("Could not send reciept notice to " + sender, exception);
acceptance.Abort();
yield break;
}
logger.DebugFormat("Reading acknowledgement about accepting messages to {0}", sender);
var acknowledgementBuffer = new byte[ProtocolConstants.AcknowledgedBuffer.Length];
var readAcknoweldgement = new AsyncEnumerator(ae.ToString());
try
{
readAcknoweldgement.BeginExecute(
StreamUtil.ReadBytes(acknowledgementBuffer, stream, readAcknoweldgement, "acknowledgement", false),
ae.End());
}
catch (Exception exception)
{
logger.Warn("Error reading acknowledgement from " + sender, exception);
acceptance.Abort();
yield break;
}
yield return(1);
try
{
readAcknoweldgement.EndExecute(ae.DequeueAsyncResult());
}
catch (Exception exception)
{
logger.Warn("Error reading acknowledgement from " + sender, exception);
acceptance.Abort();
yield break;
}
var senderResponse = Encoding.Unicode.GetString(acknowledgementBuffer);
if (senderResponse != ProtocolConstants.Acknowledged)
{
logger.WarnFormat("Sender did not respond with proper acknowledgement, the reply was {0}",
senderResponse);
acceptance.Abort();
}
bool commitSuccessful;
try
{
acceptance.Commit();
commitSuccessful = true;
}
catch (Exception exception)
{
logger.Warn("Unable to commit messages from " + sender, exception);
commitSuccessful = false;
}
if (commitSuccessful == false)
{
bool writeSuccessful;
try
{
stream.BeginWrite(ProtocolConstants.RevertBuffer, 0, ProtocolConstants.RevertBuffer.Length,
ae.End(),
null);
writeSuccessful = true;
}
catch (Exception e)
{
logger.Warn("Unable to send revert message to " + sender, e);
writeSuccessful = false;
}
if (writeSuccessful)
{
yield return(1);
try
{
stream.EndWrite(ae.DequeueAsyncResult());
}
catch (Exception exception)
{
logger.Warn("Unable to send revert message to " + sender, exception);
}
}
}
}
}
finally
{
var copy = CompletedRecievingMessages;
if (copy != null)
{
copy();
}
}
}
