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NetMQ (ZeroMQ) how to make "Brokerless Reliability (Freelance Pattern)" works

I facing some problems with the example I got from the ZeroMQ Guide, looks like the class ZSocket and ZContext doesn't exist.
I'm totally new with ZeroMQ (just start lo learn) and I'm following the "ØMQ - The Guide". The first example about REQ-REP, which is very simple, worked well. But now I'm trying something more similar to my objective, the "Brokerless Reliability (Freelance Pattern)" and this one didn't work.
I'm using Visual Studio 2019 with C# code, I created a new project, added NetMQ V4.0.1.6 via Nuget and copied the server code to my project. I got errors with ZContext and ZSocket. I already check the API V3 and API V4, they are clear different. The guide is totally based on version 3 and I'm using V 4. I didn't find any document about the changes or updates or equivalent function/classes/methods and I don't know how to convert the example to the NetMQ V4.
This is my test code:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using NetMQ;
namespace Examples
{
static partial class Program
{
public static void FLServer1(string[] args)
{
//
// Freelance server - Model 1
// Trivial echo service
//
// Author: metadings
//
if (args == null || args.Length < 1)
{
Console.WriteLine();
Console.WriteLine("Usage: ./{0} FLServer1 [Endpoint]", AppDomain.CurrentDomain.FriendlyName);
Console.WriteLine();
Console.WriteLine(" Endpoint Where FLServer1 should bind on.");
Console.WriteLine(" Default is tcp://127.0.0.1:7780");
Console.WriteLine();
args = new string[] { "tcp://127.0.0.1:7780" };
}
using (var context = new ZContext())
using (var server = new ZSocket(context, ZSocketType.REP))
{
server.Bind(args[0]);
Console.WriteLine("I: echo service is ready at {0}", args[0]);
ZMessage message;
ZError error;
while (true)
{
if (null != (message = server.ReceiveMessage(out error)))
{
using (message)
{
server.Send(message);
}
}
else
{
if (error == ZError.ETERM)
return; // Interrupted
throw new ZException(error);
}
}
}
}
}
}

After long hours trying to understand that logic, I found a list of differences from ZeroMQ V3 and V4:
https://github.com/zeromq/netmq/wiki/Migrating-to-v4
Also, accidentally I found the example I was looking for:
https://github.com/NetMQ/Samples/tree/master/src/Brokerless%20Reliability%20(Freelance%20Pattern)/Model%20One

Embedded Nancy not listening

I read a couple of related questions which had an issue with accessing nency from a remote computer. However, I am unable to access nancy from my own pc.
Here is my code:
class Program
{
static void Main(string[] args)
{
HostConfiguration hostConfigs = new HostConfiguration();
//hostConfigs.RewriteLocalhost = true;
hostConfigs.UrlReservations.CreateAutomatically = true;
using (var host = new NancyHost(hostConfigs, new Uri("http://localhost:1234")))
{
host.Start();
Console.WriteLine("Running on http://+:1234");
Console.WriteLine(host.ToString());
}
Console.ReadKey();
}
}
public class HelloModule : NancyModule
{
public HelloModule()
{
Get["/"] = parameters => Response.AsJson("Success");
Get["/nancy"] = parameters => Response.AsJson("Success");
}
}
}
I am administrator on my PC and I do not get any exception. If I type http://localhost:1234 or http://127.0.0.1:1234 to my browser (with /nancy and without) I would expect a response. However, I do net get any reponse. Further, in the list produced with netstat -ano I do not see any process listing on port 1234. I downloaded the latest version of nancy via nuget.
Do you have any idea?

The following line should work as expected:
var host = new NancyHost(hostConfigs, new Uri("http://localhost:1234"))
But what happens with a using statement, is that anything specified between ( and ) (simply put) is disposed after the closing brace (}) of the same using statement. So what is actually happening is, the host gets created, is started, and is disposed right after it printed some lines to the console.
Simply put, move the ReadKey call inside the using statement. There it will wait until a key is pressed, and the host will be disposed after that event has occurred.

Error : The status callback on localhost is not a valid URL

I'm trying to make an application that can send sms using twilio API
This API contains statusCallback attributes, which we can include a link that the API can send data about the delivery behavior ( if sms are received etc...)
public void sendSMS()
foreach (var toNumber in TOnumbersList)
{
var message = MessageResource.Create(
to: new PhoneNumber(toNumber),
from: new PhoneNumber(fromNumber),
body: msgBody,
provideFeedback: true,
statusCallback: new Uri("http://localhost:5000/"));// <----
}
As you can notice , in the statusCallback I precised that I would like to send the information on localhost:5000/
In my solution explorer of visual studio 2015 I added a separated project and called it windows Service
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.ServiceProcess;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
namespace WindowsService
{
static class Program
{
/// <summary>
/// The main entry point for the application.
/// </summary>
static void Main()
{
ServiceBase[] ServicesToRun;
ServicesToRun = new ServiceBase[]
{
new Service1()
};
// ServiceBase.Run(ServicesToRun);
_httpListener.Prefixes.Add("http://localhost:5000/"); // add prefix "http://localhost:5000/"
_httpListener.Start(); // start server (Run application as Administrator!)
Console.WriteLine("Server started.");
Thread _responseThread = new Thread(ResponseThread);
_responseThread.Start(); // start the response thread
}
static HttpListener _httpListener = new HttpListener();
static void ResponseThread()
{
while (true)
{
HttpListenerContext context = _httpListener.GetContext(); // get a context
var a = context.Request.Url; // Now, you'll find the request URL in context.Request.Url
byte[] _responseArray = Encoding.UTF8.GetBytes("<html><head><title>Localhost server -- port 5000</title></head>" +
"<body>Welcome to the <strong>Localhost server</strong> -- <em>port 5000!</em></body></html>"); // get the bytes to response
context.Response.OutputStream.Write(_responseArray, 0, _responseArray.Length); // write bytes to the output stream
context.Response.KeepAlive = false; // set the KeepAlive bool to false
context.Response.Close(); // close the connection
Console.WriteLine("Respone given to a request.");
}
}
}
}
After that , in the configuration of the solution I precised that I wanted the service to run before the windows form project as you can notice in the picture
So once I start the solution , I went on localhost:5000 and noticed that the service is running and the page is displaying a welcoming message
But , once the sendSMS() function is called (or invoked ) ( while the service is running) I'm receiving this error :
Error : The status callback on localhost is not a valid URL
So my question is what I am doing wrong ? I would like to understand I am not very experienced with the web service techniques , did I forget to enable something? Or something related to asynchronous and synchronous issue ?
Note : In the past , (instead of using local-host ) , I have created a url using http://requestb.in/ ( which does the job of a webservice) and I have copied the created url and there was no problem sending data on the link . But with when the link is localhost , the issue is noticed

"Localhost" resolves to the machine the code is currently running on, which is 127.0.0.1 (IPv4) and ::1 (IPv6).
If you pass localhost to a remote service like Twilio, the remote service will resolve "localhost" to 127.0.0.1/::1, which is itself. This doesn't make any sense and is why Twilio rejects the URL.
The callback URL you specify must be public and reachable from Twilios services, otherwise this won't work. I usually use a cheap or free Azure website for tests like this.

pass telephone to default windows softphone while its running

I developed a softphone for windows, I know how to register it as default tell application by reading this question, but I don`t know how get arguments sent from a web application or another win application while my softphone is running.
The standard code to call tell app from web app is something like this:
window.open("tel: 05525825");

If you have registered your application for the scheme tel: and the Command is "yourapp.exe %1", then you can read them from the commandline arguments as explained in How to access command line parameters outside of Main in C#:
string arguments = Environment.GetCommandLineArgs();
string phoneNumber = arguments[1];
Of course you need to do some sanity checking before bluntly accessing and using the array element.

If you setup the protocol URL keys correctly your application will be run with the data in the command line (E.g. args[] in main())
To pass data to an already running instance of your application the easiest way is to use the StartupNextInstance event provided by VisualBasic.ApplicationServices and re-process new incomming command lines:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Forms;
using Microsoft.VisualBasic.ApplicationServices;
namespace Foo
{
static class Program
{
[STAThread]
static void Main(string[] args)
{
var applicationBase = new ThisWindowsApplicationBase();
applicationBase.StartupNextInstance += (sender, e) => { applicationBase.HandleCommandLine(e.CommandLine); };
applicationBase.Run(args);
}
}
class ThisWindowsApplicationBase : WindowsFormsApplicationBase
{
internal ThisWindowsApplicationBase()
: base()
{
this.IsSingleInstance = true;
this.MainForm = new Form1();
this.HandleCommandLine(Environment.GetCommandLineArgs().Skip(1));
}
internal void HandleCommandLine(IEnumerable<string> commandLine)
{
this.MainForm.Text = "Processing: " + commandLine.FirstOrDefault();
}
}
}
Note this will not fire for the first run.

Why thread is stopped when start new process, while application (c#) is still running?

Is there any problem which i have to do carefully when starting new process in multiple thread application?
I tried this in a simple project:
static void Main(string[] args)
{
Process.Start(#"D:\System\Desktop\a.txt");
MessageBox.Show("Success");
}
And it runs perfectly. But when i do it in my big project which use multiple thread, it's thread is stopped working ("a.txt" is opened but "Success" is not shown) while my application (other thread) do well.
What is the problem in this situation?

If you have a Windows.Forms application and you try to show a message-box from a thread that is not the main user-interface thread, the behavior of the message-box is undefined. Meaning, it may or may not show, be inconsistent, or some other problem.
For instance, displaying a message-box from the BackgroundWorker's DoWork event may or may not work. In one case, the message-box-result was always cancel regardless of what button was clicked.
Therefore, if you are using a message-box just for debugging purposes, use a different technique. If you have to show a message-box, call it from the main user-interface thread.
A console-application should normally not have problems displaying message-boxes. Yet, I have had cases where I would have to sleep the thread for 100ms before the message-box call.
Note, as TomTom pointed out, the main user-interface thread is the application's Windows message loop. Which reminds me, I once had to create a Form in a Console application in order to create a Windows message loop, so my application could respond to Windows messages.

This isn't the answer - I can't put all this code in a comment...
This works for me. Tell me how your code differs from this:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;
using System.Threading;
using System.IO;
namespace Test
{
class Program
{
const string OutputFile = #"E:\Output.txt";
object _lock = new object();
static void Main(string[] args)
{
Program program = new Program();
Thread thread = new Thread(program.ThreadMethod);
thread.Start(#"E:\Test.txt");
thread = new Thread(program.ThreadMethod);
thread.Start(#"E:\DoesntExist.txt");
Console.ReadKey();
}
void ThreadMethod(object filename)
{
String result = RunNormal(filename as string);
lock (_lock)
{
FileInfo fi = new FileInfo(OutputFile);
if (!fi.Exists)
{
try
{
fi.Create().Close();
}
catch (System.Security.SecurityException secEx)
{
Console.WriteLine("An exception has occured: {0}", secEx.Message);
return;
}
}
StreamWriter sw = fi.AppendText();
sw.WriteLine(result);
sw.Close();
}
}
string RunNormal(string fullfilename)
{
try
{
Process.Start(fullfilename);
return fullfilename + "|Success";
}
catch (Exception e)
{
return fullfilename + "|" + e.ToString();
}
}
}
}
The output in Output.txt is:
E:\DoesntExist.txt|System.ComponentModel.Win32Exception (0x80004005): The system cannot find the file specified
at System.Diagnostics.Process.StartWithShellExecuteEx(ProcessStartInfo startInfo)
at System.Diagnostics.Process.Start()
at System.Diagnostics.Process.Start(ProcessStartInfo startInfo)
at System.Diagnostics.Process.Start(String fileName)
at Test.Program.RunNormal(String fullfilename) in E:\Projekti\VS2010\Test\Test\Program.cs:line 59
E:\Test.txt|Success
How much different is your code? Do you call some other methods? How do you process the results?

Make sure Process.Start works. Passing a filename is not good enough in some cases. In you sample code, you would have to set the use-shell property; otherwise, you would have to use cmd start <filename> or equivalent.
Therefore, just start NotePad.exe to make sure Process.Start works. If it does then your problem is the process command and command line.