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RabbitMQ Consumer/Reciever not working in C# Windows Form

I am currently working with the rabbitMQ server, As when i try working in c# console application, the publish exchange working and successfully save in the server and the message will lively appear in the console but when i apply my source code in the C# windows form, it will not get all the message sent by the publisher. I put the method in the constructor event but no happen at all it will not receive any message.
Please see source code below
using Publisher;
using RabbitMQ.Client;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using System.Timers;
using RabbitMQ.Client.Events;
using System.Diagnostics;
namespace Consumer
{
public partial class Consumer : Form
{
private EventingBasicConsumer consumer;
ConnectionFactory factory;
public Consumer()
{
factory = new ConnectionFactory() { HostName = Definition.HOSTNAME };
using (var connection = factory.CreateConnection())
using (var channel = connection.CreateModel())
{
channel.ExchangeDeclare(exchange: Definition.EXCHANGE, type: ExchangeType.Fanout);
var queueName = channel.QueueDeclare().QueueName;
channel.QueueBind(queue: queueName,
exchange: Definition.EXCHANGE,
routingKey: "");
Debug.WriteLine(" [*] Waiting for Exchange ARexchange.");
var consumer = new EventingBasicConsumer(channel);
consumer.Received += (sender, ea) =>
{
var body = ea.Body;
var message = Encoding.UTF8.GetString(body);
Debug.WriteLine(" [x] {0}", message);
};
channel.BasicConsume(
queueName,
autoAck: false,
consumer: consumer);
}
InitializeComponent();
}
private void Consumer_Load(object sender, EventArgs e)
{
}
private void setExchange()
{
lblExchange.Text = Definition.EXCHANGE;
}
}
}

Please read this: https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/using-statement
using (var connection = factory.CreateConnection())
using (var channel = connection.CreateModel())
When those using statements exit, the channel and connection will be closed. Change your code to save those as instance variables in the Consumer class. Then, when your form exits, you can clean up those two instances.
If you provide your code in a repository that can be cloned, compiled and run people could assist you by submitting pull requests to improve your code.
NOTE: the RabbitMQ team monitors the rabbitmq-users mailing list and only sometimes answers questions on StackOverflow.

XMPP connection hanging on "Resource Binding" process using xmedianet library

As a complete beginner in the field of instant messaging (using XMPP protocol), as well as windows phone 8.1 app development; I am trying to start off by using xmedianet library in order to connect to a server and communicate using XMPP protocol. After implementing the following example and tweaking it to my needs.
Here's the part of the code where I configure the connection parameters:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Navigation;
using Microsoft.Phone.Controls;
using Microsoft.Phone.Shell;
using WP8Xmpp.Resources;
using System.Net.XMPP;
using System.Net.Sockets;
using System.Threading;
namespace WP8Xmpp
{
public partial class MainPage : PhoneApplicationPage
{
private Boolean IsXmppSuccess { get; set; }
/// <summary>
/// Xmpp Client
/// </summary>
public XMPPClient ObjXmppClient { get; set; }
/// <summary>
/// XMPP Connection
/// </summary>
public XMPPConnection ObjXmppCon { get; set; }
// Constructor
public MainPage()
{
InitializeComponent();
}
private void btnLogin_Click(object sender, RoutedEventArgs e)
{
IsXmppValid();
}
private void IsXmppValid()
{
ObjXmppClient = new XMPPClient();
//initializing the xmpp client with credentials
ObjXmppClient.JID = "user#domain.com";
ObjXmppClient.JID.Resource = Guid.NewGuid().ToString();
ObjXmppClient.Password = "acc_password";
ObjXmppClient.Server = "server_uri";*/
ObjXmppClient.AutoReconnect = true;
ObjXmppClient.Port = 81; // I've already tried 5222 but 81 is the correct port in this server's case.
ObjXmppClient.RetrieveRoster = true;
ObjXmppClient.PresenceStatus = new PresenceStatus() { PresenceType = PresenceType.available, IsOnline = true };
ObjXmppClient.AutoAcceptPresenceSubscribe = true;
ObjXmppClient.AttemptReconnectOnBadPing = true;
ObjXmppCon = new XMPPConnection(ObjXmppClient);
ObjXmppCon.Connect();
ObjXmppClient.Connect();
//initializing the xmpp connection
ObjXmppCon.OnAsyncConnectFinished += ObjXmppCon_OnAsyncConnectFinished;
ObjXmppClient.OnStateChanged += new EventHandler(xMPPClient_OnStateChanged);
Thread.Sleep(2000);
} ...
When I launch this application using the WP 8.1 emulator and attempt a connection. Everything works fine until the Resource Binding step. I get the following output on the VS2013 console:
<--stream:features><ver xmlns="urn:xmpp:features:rosterver"/><compression xmlns="http://jabber.org/features/compress"><method>zlib</method></compression><bind xmlns="urn:ietf:params:xml:ns:xmpp-bind"/><session xmlns="urn:ietf:params:xml:ns:xmpp-session"/></stream:features>
Setting state to CanBind
Setting state to Binding
<--<
<--iq id="xxxxxxxx-xxxx-xxxx-xxxx-0f08b82b9f1f" to="user#domain/Resource" xmlns="jabber:client" type="result"><bind xmlns="urn:ietf:params:xml:ns:xmpp-bind"><jid>user#domain/Resource</jid></bind></iq>
Followed by nothingness except for a few "thread exit" messages and the program terminating after a few minutes.
I've been at it for days now.. I've tried all possible scenarios for the connection parameters, even tried fiddling with the library's code to no avail. Could anyone try to replicate this configuration with the same library to see if it's a problem on my side?
Note: connection to the server with the same account using another xmpp client works just fine.

Turned out the problem was that, for some reason, the "Bound" state was not firing even though the binding attempt returned a successful result. I've managed to "fix" this the ugly way by using Thread.sleep() and then changing the state manually to "bound" (note that the same trick is used to get to the "session" state). Here's a sample of my "patchwork" code:
void xMPPClient_OnStateChanged(object sender, EventArgs e)
{
switch (ObjXmppClient.XMPPState)
{
case XMPPState.Binding:
this.Dispatcher.BeginInvoke(() =>
{
Thread.Sleep(2000);
ObjXmppClient.XMPPState = System.Net.XMPP.XMPPState.Bound;
}
);
break;
case XMPPState.Sessioning:
this.Dispatcher.BeginInvoke(() =>
{
Thread.Sleep(2000);
ObjXmppClient.XMPPState = System.Net.XMPP.XMPPState.Session;
}
);
break; ...

WPF C# application will freeze my whole computer ever 2-3 times I run it

I put a lot of information in this issue because I have no idea what will be relavent
Issue:
I am having an issue with a program I am working on where when running it, it will freeze my whole computer and return no error (I am completely incapable of doing anything CTRL+ALT+DEL doesn't even work). This program accepts a connection from a android client and atm the android client is not configured correctly so the connection is being rejected.
Question:
How can I stop my program from freezing my entire machine?
Conjecture:
I have a few theories as to what is going on but no idea how to fix them. I have read that this may have something to do with me running a single threaded process inside my async worker but I am not sure that the socket is a single threaded process. Also I am not entirely sure how I am supposed to deal with exceptions in a backgroundworker so I just let it fall back to the RunWorkerCompletedEventArgs then retrieve the error message from there.
What I have tried:
- I tried putting try catches every where then removing try catches nothing seems to be able to capture this error
- I checked my systems event log and nothing is showing up except my restarts after my computer freezes
- I have attempted to isolate the issue but it can literally happen at any point from the program starting till when I attempt to connect
Setup:
I am running the program out of visual studio 2012 professional on a windows 8 pro machine. The computer I am on has a i7-3770K 3.50GHz and 32GB of ram. The application that is attempting to make a connection to mine is a Android application and the credentials are incorrect when it is attempting to connect. Visual Studio is running off my main hard drive and building the project on another drive.
Closing:
With all that said would some one please be willing to help me? If you need any more information I will be happy to provide it, please ask.
Main Method:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.ComponentModel;
namespace Server
{
/// <summary>
/// Interaction logic for MainWindow.xaml
/// </summary>
public partial class SourceServer : Window
{
private BackgroundWorker worker = new BackgroundWorker();
public SourceServer()
{
InitializeComponent();
StartListeningForConnections();
}
private void StartListeningForConnections()
{
worker.DoWork += new DoWorkEventHandler(worker_DoWork);
worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(worker_RunWorkerCompleted);
worker.ProgressChanged += new ProgressChangedEventHandler(worker_ProgressChanged);
worker.WorkerReportsProgress = true;
if (worker.IsBusy != true)
{
worker.RunWorkerAsync();
}
}
private void worker_DoWork(object sender, DoWorkEventArgs e)
{
worker.ReportProgress(0, "Source server version 0.0.0.1ib started");
LoginServer oLoginServer = new LoginServer();
oLoginServer.StartListening(worker);
}
private void worker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
try
{
lvOutput.Items.Add(e.UserState.ToString());
}
catch (Exception exception)
{
lvOutput.Items.Add(exception.StackTrace);
}
}
private void worker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
if (e.Error != null)
{
System.IO.File.WriteAllText(Environment.CurrentDirectory + #"\log.txt", e.Error.StackTrace + " /n " + e.Error.Message);
}
else
{
MessageBox.Show("Error was null");
}
worker.Dispose();
}
}
}
SSL Socket Connection:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;
using System.Net;
using System.Net.Sockets;
using System.Windows;
using System.Windows.Controls;
using System.ComponentModel;
using System.Net.Security;
using System.Security.Cryptography.X509Certificates;
using MySql.Data.MySqlClient;
using System.IO;
namespace Server
{
public class LoginServer
{
// Incoming data from the client.
public static string data = null;
public static X509Certificate serverCertificate = null;
public delegate void UpdateListView(ListView oOutput);
public void StartListening(BackgroundWorker worker)
{
// Data buffer for incoming data.
byte[] bytes = new Byte[1024];
// Establish the local endpoint for the socket.
IPHostEntry ipHostInfo = Dns.GetHostEntry(Dns.GetHostName());
IPAddress ipAddress = ipHostInfo.AddressList[1];
serverCertificate = X509Certificate.CreateFromCertFile(#"server.crt");
TcpListener oServer = new TcpListener(ipAddress, 12345);
// Bind the socket to the local endpoint and
// listen for incoming connections.
// Start listening for connections.
while (true)
{
Thread.Sleep(100);
worker.ReportProgress(0, "Waiting for connection....");
// Program is suspended while waiting for an incoming connection.
//Socket handler = listener.Accept();
oServer.Start();
TcpClient oClient = oServer.AcceptTcpClient();
Stream oStream = oClient.GetStream();
SslStream oSSLStream = new SslStream(oStream);
data = null;
// An incoming connection needs to be processed.
string sUsername = "place holder";
string sPassword = "place holder";
while (true)
{
bytes = new byte[1024];
int bytesRec = oSSLStream.Read(bytes, 0, bytes.Length);
data += Encoding.ASCII.GetString(bytes, 0, bytesRec);
string[] sCredentials = data.Split("|".ToCharArray()[0]);
sUsername = sCredentials[0];
sPassword = sCredentials[1];
if (data.IndexOf("<EOF>") > -1)
{
break;
}
}
// Show the data on the console.
worker.ReportProgress(0, "Connection Recieved : ");
worker.ReportProgress(0, "Username: " + sUsername);
worker.ReportProgress(0, "Password: " + sPassword);
worker.ReportProgress(0, "");
// Echo the data back to the client.
byte[] msg;
if (sUsername.Equals("test") && sPassword.Equals("test"))
{
msg = Encoding.ASCII.GetBytes("approved<EOF>\n");
worker.ReportProgress(0, "approved");
oSSLStream.Write(msg, 0, msg.Length);
}
else
{
msg = Encoding.ASCII.GetBytes("rejected<EOF>\n");
worker.ReportProgress(0, "rejected");
oSSLStream.Write(msg, 0, msg.Length);
}
}
}
public void VerifyUser()
{
}
}
}

While I don't see any reason for this to lock up your entire computer, I do see a couple of reasons for the application to potentially hang...
Your while loop inside of your SSL server will never break unless your client writes '<EOF>' to the stream; which you would have to force it to do. I would likely do something similar to this:
while(( bytesRec = oSSLStream.Read(bytes,0,bytes.Length)) > 0 )
{
// Compare input & break
}
-- The while loop you have now ( without a thread sleep ) will consume all of your systems resources waiting for ... something that may never occur.
In a related issue - I note that your 'DoWork' method launches the listener - but does not start a new thread for this listener. This means that the listener is running inside of your interface thread - which will cause the interface ( and potentially more... ) to hang until the process is completed - which as stated, may never happen.
... Ahem... This last paragraph may be incorrect - you are running an async worker, so I may be incorrect in my second assessment.
Cheers, hope this is helpful.

I've had some hanging problems on Windows 8 that I never saw on Windows 7 (with VS2012). As you experienced it worked fine the first time but only locked up Visual Studio (and not my whole machine) and I had to force quit.
The Visual Studio 2012 Update 4 (which focuses on bug fixes and compatibility) seemed to fix it, although I didn't scientifically test this.
Note: As of 9/1/13 this is only the RC2 version so please check for newer versions, and edit this answer when RTM happens.

In C#, Illegal Cross Threading. Connecting to STOMP server

I'm having this issue. I need to be able to append the incoming messages to txtConsole from within OnMessage, but I'm getting an Illegal Cross Thread error. How do I get around this? I'm pretty basic when it comes to C# so some code (no psuedocode) with explanations would be helpful please.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using Apache.NMS;
using Apache.NMS.Util;
namespace WindowsFormsApplication1
{
public partial class frmConsole : Form
{
public frmConsole()
{
InitializeComponent();
}
private void Form1_Load(object sender, System.EventArgs e)
{ }
public void cmdConnect_Click(object sender, EventArgs e)
{
// Output to the user that the connection is being set up
txtConsole.AppendText(Environment.NewLine + "Setting up connection...");
// Define the feed URL
IConnectionFactory factory = new NMSConnectionFactory(new Uri("stomp:tcp://datafeeds.networkrail.co.uk:61618"));
// Define the credentials
IConnection connection = factory.CreateConnection("REDACTED", "REDACTED");
// Create the session
ISession session = connection.CreateSession();
// Specify which feed - we want TRAIN_MVT_ALL_TOC to listen for all train movements
IDestination destination = session.GetDestination("topic://" + "TRAIN_MVT_ALL_TOC");
// Let the end user know where we will be subscribing to
txtConsole.AppendText(Environment.NewLine + "Will attempt subscription to " + destination);
// Create a consumer for the feed
IMessageConsumer consumer = session.CreateConsumer(destination);
// Let the end user know we are about to connect...
txtConsole.AppendText(Environment.NewLine + "Connecting...");
// Connection details are now all set up. Start the connection...
connection.Start();
// Check we are connected
if (connection.IsStarted == false)
{
txtConsole.AppendText(Environment.NewLine + "Connection closed.");
connection.Close();
}
// Now we need to handle messages using a MessageListener where we pass it to the OnMessage void.
consumer.Listener += new MessageListener(OnMessage);
txtConsole.AppendText(Environment.NewLine + "Connection established. Waiting for messages...");
// End of void
}
public void OnMessage(IMessage message)
{
ITextMessage msg = (ITextMessage)message;
message.Acknowledge();
txtConsole.AppendText(Environment.NewLine + msg.Text);
}
}
}

The reason you're getting that error is because you're trying to update a UI element from a non-UI thread. You can call the control's Invoke method to force it to run on the UI thread.
public void OnMessage(IMessage message)
{
ITextMessage msg = (ITextMessage)message;
message.Acknowledge();
if (txtConsole.InvokeRequired)
{
txtConsole.Invoke(new Action(() =>
{
txtConsole.AppendText(Environment.NewLine + msg.Text);
}));
}
else
{
txtConsole.AppendText(Environment.NewLine + msg.Text);
}
}

That exception appears when you try to access other thread (for example, UI Thread), from another different thread.
You can solve that calling
Dispatcher.BeginInvoke(() => delegate{// Here the code});
from any thread you want

How to Properly Handle Cross-thread Events and Update a Label with BeginInvoke and BackgroundWorker
Cross Thread UI control access
Just replace txtConsole.AppendText in method OnMessage with
txtConsole.Invoke((Action)(() => txtConsole.AppendText(Environment.NewLine + msg.Text)));

Using the TFS 2010 API to subscribe to Workspace Events

I'm trying to write some code that monitors the TFS workspace(s) on my local workstation but at the moment I'm having problems getting the events to fire.
For example if I map a new folder in my workspace I want to subscribe to the versionControl.UpdatedWorkspace event, and if I do a “get” I want to map to the versionControl.Getting event. The code below is a console application that I think should work, but when I do a get nothing happens. Does anyone know how to successfully subscribe to these events?
VS2010, TFS 2010, WinXP SP3
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Net;
using System.Text;
using Microsoft.TeamFoundation.Client;
using Microsoft.TeamFoundation.Framework.Client;
using Microsoft.TeamFoundation.Framework.Common;
using Microsoft.TeamFoundation.VersionControl.Client;
namespace TestEventHanling
{
class Program
{
static void Main(string[] args)
{
Uri serverUri = new Uri(#"http://TfsServer:8080/tfs/collection");
using (TfsTeamProjectCollection collection = new TfsTeamProjectCollection(serverUri, CredentialCache.DefaultCredentials))
{
VersionControlServer versionControl = (VersionControlServer)collection.GetService(typeof(VersionControlServer));
versionControl.UpdatedWorkspace += new WorkspaceEventHandler(OnUpdatedWorkspace);
versionControl.Getting += new GettingEventHandler(OnGetting);
Console.WriteLine("Press \'q\' to quit.");
while (Console.Read() != 'q') ;
}
}
internal static void OnUpdatedWorkspace(object sender, WorkspaceEventArgs e)
{
foreach (WorkingFolder wf in e.Workspace.Folders)
{
Console.WriteLine("Workspace updated {0}", wf.ServerItem);
}
}
internal static void OnGetting(Object sender, GettingEventArgs e)
{
Console.WriteLine("Getting: {0}, status: {1}", e.TargetLocalItem, e.Status);
}
}
}

My understanding are that these are events that are on your local instance of VersionControlServer. That is to say, they will fire when you act on that instance in your code.
For example, if, somewhere else in your code, you updated a workspace, then the UpdatedWorkspace handler would fire.
There's a smaller set of events that you can subscribe to server-side (check-in, builds, etc.), but I'm not sure that you can monitor what's happening on the server through the VersionControlServer class.