static bool AssertExpectedCommandFrame(Frame frame, string expectedFrameCommand)
{
// If error
if (frame.Command == StompCommands.Error)
{
// Using the incoming frame, Interpret will create a new instance of a sub-class
// of Frame depending on the Command. If the frame is a HEARTBEAT, the same frame
// will be returned. Possible sub-classes: ConnectedFrame, ErrorFrame, MessageFrame,
// ReceiptFrame.
// Interpret throws exception if the incoming frame is malformed (not standard).
ErrorFrame errFrame = StompInterpreter.Interpret(frame) as ErrorFrame;
Console.WriteLine("ERROR RESPONSE");
Console.WriteLine("Message : " + errFrame.Message);
return(false);
}
if (frame.Command != expectedFrameCommand)
{
Console.WriteLine("UNEXPECTED FRAME.");
Console.WriteLine(frame.ToString());
return(false);
}
return(true);
}
private void OnNext(Frame frame)
{
if (frame.Command == StompCommands.Connected)
{
var connectedFrame = StompInterpreter.Interpret(frame) as ConnectedFrame;
if (connectedFrame.Heartbeat.Incoming > 0)
{
CheckKeepAlive(connectedFrame.Heartbeat.Incoming + MarginOfAcceptance);
}
if (connectedFrame.Heartbeat.Outgoing > 0)
{
SendHeartBeat((int)(Math.Max(connectedFrame.Heartbeat.Outgoing - MarginOfAcceptance, MarginOfAcceptance)));
}
}
LastActivityTime = DateTime.UtcNow;
}
public void OnNext(Frame frame)
{
//If frame command is MESSAGE.
if (frame.Command == StompCommands.Message)
{
// Using the incoming frame, Interpret will create a new instance of a sub-class
// of Frame depending on the Command. If the frame is a HEARTBEAT, the same frame
// will be returned. Possible sub-classes: ConnectedFrame, ErrorFrame, MessageFrame,
// ReceiptFrame.
// Interpret throws exception if the incoming frame is malformed (not standard).
MessageFrame message = StompInterpreter.Interpret(frame) as MessageFrame;
//Print MESSAGE frame data.
Console.WriteLine("MESSAGE FRAME");
Console.WriteLine("Destination: " + message.Destination);
Console.WriteLine("ContentType: " + message.ContentType);
Console.WriteLine("ContentLength: " + message.ContentLength);
Console.WriteLine("Content:" + message.GetBodyAsString());
Console.WriteLine();
}
}
/// <summary>
/// Example to demonstrate STOMP transactions using the StompNet low level API.
///
/// In this example, a single message is going to be sent to a queue and it will be read from
/// the same queue.
/// </summary>
public static async Task ExampleWriterAndReader()
{
using (TcpClient tcpClient = new TcpClient(serverHostname, serverPort))
// Create a frame writer and frame reader. These classes are NOT thread safe.
// Stomp12FrameWriter and Stomp12FrameReader are NOT thread safety. They could
// wrapped into a StompSerialFrameWriter and a StompSerialFrameReader for
// serializing operations (thread-safe).
using (IStompFrameWriter writer = new Stomp12FrameWriter(tcpClient.GetStream()))
using (IStompFrameReader reader = new Stomp12FrameReader(tcpClient.GetStream()))
{
Frame inFrame;
//---------------------------------
// Write CONNECT.
//
await writer.WriteConnectAsync(virtualHost, login, passcode);
// Read CONNECTED.
// Keep reading while receiving Heartbeats.
do
{
inFrame = await reader.ReadFrameAsync();
} while (inFrame.Command == StompCommands.Heartbeat);
//Verify a CONNECTED frame was received.
if (!AssertExpectedCommandFrame(inFrame, StompCommands.Connected))
{
return;
}
Console.WriteLine("Connected");
//---------------------------------
// Write SEND command with receipt.
//
await writer.WriteSendAsync(
aQueueName,
messageContent + (" (WITH RECEIPT)."),
"myreceiptid-123");
// Read RECEIPT.
// Keep reading while receiving Heartbeats.
do
{
inFrame = await reader.ReadFrameAsync();
} while (inFrame.Command == StompCommands.Heartbeat);
//Verify a RECEIPT frame was received.
if (!AssertExpectedCommandFrame(inFrame, StompCommands.Receipt))
{
return;
}
// Process incoming RECEIPT.
// Using the incoming frame, Interpret will create a new instance of a sub-class
// of Frame depending on the Command. If the frame is a HEARTBEAT, the same frame
// will be returned. Possible sub-classes: ConnectedFrame, ErrorFrame, MessageFrame,
// ReceiptFrame.
// Interpret throws exception if the incoming frame is malformed (not standard).
ReceiptFrame rptFrame = StompInterpreter.Interpret(inFrame) as ReceiptFrame;
if (rptFrame.ReceiptId != "myreceiptid-123")
{
Console.WriteLine("ERROR: Unexpected receipt " + rptFrame.ReceiptId + ".");
return;
}
Console.WriteLine("Received matching receipt.");
//---------------------------------
// Write SUBSCRIBE.
//
string subscriptionId = new Random().Next().ToString();
await writer.WriteSubscribeAsync(aQueueName, subscriptionId, ack : StompAckValues.AckAutoValue);
// Read MESSAGE.
// Keep reading while receiving Heartbeats.
do
{
inFrame = await reader.ReadFrameAsync();
} while (inFrame.Command == StompCommands.Heartbeat);
//Verify a MESSAGE frame was received.
if (!AssertExpectedCommandFrame(inFrame, StompCommands.Message))
{
return;
}
// Process incoming RECEIPT.
MessageFrame msgFrame = StompInterpreter.Interpret(inFrame) as MessageFrame;
Console.WriteLine("Received Message:");
Console.WriteLine();
Console.WriteLine("Destination: " + msgFrame.Destination);
Console.WriteLine("ContentType: " + msgFrame.ContentType);
Console.WriteLine("ContentLength: " + msgFrame.ContentLength);
Console.WriteLine("Content:" + msgFrame.GetBodyAsString());
Console.WriteLine();
// Write DISCONNECT.
await writer.WriteDisconnectAsync();
Console.WriteLine("Disconnected.");
}
}
