Zyan with Windows and Mono on Linux Raspberry

[guehmann]

Hi Yallie,

here is a little bit about my Zyan project on Windows, Linux and Linux on Raspberry PI 2/3.
The project is about a Time Tracking Solution, Raspberry PI with Touch Panel 3,5" and RFID reader. Should act as time tracking terminal and optional as area access terminal via a relay or led to simulate access.

All the components are wired on a breadboard and are working fine. Raspberry IO are managed via Raspberry IO General Purpose assembly on NuGet.

The environment is as following:

I have a Windows Zyan Host (Dispatcher) running as service.
I have 4 Zyan Hosts called Agent, 1 on Windows, 1 on Linux Ubuntu with Mono and 2 on Linux Ubuntu with Mono on Raspberry PI 3b.

The Windows Dispatcher is the central program making requests to the clients (agents) and receives request from the clients (agents).

Windows Agent and Linux Agent on Ubuntu are only for testing/debugging purpose. The two Raspberry Linux Agents are the real time tracking and area access terminals.

Raspberry agents have MongoDB locally installed and save the actual time bookings in the database and send a time booking request to the dispatcher (windows service) if available. If not available, later the dispatcher tries to get the bookings from the agents.

Bidirectional Communication and it works.. (Windows <-> Linux/Mono, Windows <-> Raspberry/Mono, Linux/Mono <-> Raspberry/Mono)

But...I have some strange behavior:

Sending request from the dispatcher:

 - to a windows agent
   (works fine within milliseconds)

 - to a linux/ubuntu/mono agent
   (does not work on first call, after a retry the request it works within milliseconds)

 - to a linux/ubuntu/mono/raspberry
   (same behavior as before)

If a make a "QueryAlive" request to all my agents, the first Linux/Mono gets an error with the following message:

Cannot create channel sink to connect to URL /98b09d86_a7b0_4134_91fd_a73b5be56b4a/tuemzdslijppnf8agyjtj7li_3.rem. An appropriate channel has probably not been registered.

If I try it just after this call, every is fine. First call does not succeed.

Every agent has a method to send booking data to the dispatcher, this is the behavior:

 - sending from windows/agent to windows/dispatcher
   (everything is fine within milliseconds)

 - sending from ubuntu/mono real workstation to windows/dispatcher
   (everything is fine within milliseconds)

 - sending from Raspberry/ubuntu/mono to windows/dispatcher
   (works, but the time connection to dispatcher varies from 3 to 12 seconds) 

This is my method to contact the agents/dispatcher...

using (var conn = new ZyanConnection(url, protocol))
{
var proxy = conn.CreateProxy();
var ts = proxy.QueryAlive();
}

Any idea about this behavior???
But it works with the workarounds.

Thanks, Jens.

[yallie]

Hello Jens!

Thanks a lot for your detailed description! 👍
Great to know it runs on architectures I never tried myself :)

Cannot create channel sink to connect to URL /98b09d86_a7b0_4134_91fd_a73b5be56b4a/tuemzdslijppnf8agyjtj7li_3.rem. An appropriate channel has probably not been registered.

Never seen this error in such situation. The error usually means (surprise!) that we have no registered channel of the given type, so the error's not gonna fix by itself. But in your case it magically goes away on the second call... That's unusual.

Ok, let's try to reproduce it under the debugger. What version of Mono are you using? Does it behave the same on the latest version of Mono? On Windows version of Mono? Can you post a small console program that demonstrates this behavior? You can use this gist as a starting point for your sample (async/await stuff isn't relevant here and can be stripped away to make it simpler).

Regards, Alexey

[yallie]

(works, but the time connection to dispatcher varies from 3 to 12 seconds)

BTW, do you use encryption? I saw such delays when running encrypted connections on a very low-end CPUs (RSA key generation is computation-intensitive, I think). Try disabling the encryption, perhaps it'll speed things up.

[guehmann]

Hello Alexey,

thank you for your help.

I did not turn on encryption explicit. Is it encrypted by default? How can I turn it off?

Environment is:

- Windows 10 / .NET 4.5.1 / Zyan 2.8
- Linux / Ubuntu Mate 16.04.1 LTS / Mono 4.6.1 / Zyan 2.8 / (same on Raspberry)

all programs (dispatcher and agents) using this code:

using System;
using System.Net;
using System.Reflection;
using Anytime.Agent.Model;
using Anytime.Remoting.Contract;
using Zyan.Communication;
using Zyan.Communication.Protocols.Tcp;

namespace Anytime.Agent
{
	class MainClass
	{
		private static ZyanComponentHost Host { get; set; }
		private static AgentConfig settings;
		private static DateTime StartTime = DateTime.Now;

		// Haupteinstiegspunkt...
		public static void Main(string[] args)
		{
			bool done = false;

			try
			{
				string hostname = Dns.GetHostName().ToUpper() ?? "localhost";

				// Host registrieren...
				var protocol = new TcpDuplexServerProtocolSetup(8012);
				Host = new ZyanComponentHost("test-service", protocol);

				Host.RegisterComponent<IAgent, AgentService>();

				// Warten bis Ende per ESC Taste gewünscht wird...
				Console.WriteLine();
				Console.WriteLine("Press ESC to stop the agent, BACKSPACE to simulate booking request...");

				do 
				{
					switch (Console.ReadKey(true).Key)
					{
						case ConsoleKey.Escape:
							done = true;
							break;

						case ConsoleKey.Backspace:
							SendBookingData();
							break;

						default:
							break;
					}

					Console.Write("Incoming: {0} | Outgoing: {1} | Success: {2} | Error: {3} | Fatal: {4}\r",
					             CountI, CountO, CountS, CountE, CountF);
				} while (!done);
			}
			catch (Exception e)
			{
				Console.WriteLine("Error...Reason: {0}", e.Message);
			}
		}

		// Sende Buchungsdaten an den Dispatcher...
		private static void SendBookingData()
		{
			string host = "192.168.22.192";
			int dispatcherPort = 8012;
			string dispatcherService = "test-agent1";
			var protocol = new TcpDuplexClientProtocolSetup();
			var url = protocol.FormatUrl(host, dispatcherPort, dispatcherService);

			// Verbindung zum Host herstellen...
			try
			{
				config = DispatcherConfig.GetConfiguration();
				var protocol = new TcpDuplexClientProtocolSetup();
				var url = protocol.FormatUrl(config.Host, config.Port, config.Service);

				Console.WriteLine("(O:->) Try connecting to dispatcher on host {0}, port {1} with service {2}...",
								  config.Host, config.Port, config.Service);
				
				using (var conn = new ZyanConnection(url, protocol))
				{
					var proxy = conn.CreateProxy<IDispatcher>();
					proxy.SendTerminalData(Dns.GetHostName(), "004711", 0, 10100, DateTime.Now, false);
				}
			}
			catch (Exception e)
			{
				Console.WriteLine("(O:->) Connection to dispatcher failed. Reason: {0}", e.Message);
			}
		}

		// Dienstmethoden des Agent...
		internal class AgentService : IAgent
		{
			// Einfache Anfrage, ob der Agent noch verfügbar ist, und wenn, seit wann...
			public TimeSpan QueryAlive()
			{
				try
				{
					CountI++;
					Console.WriteLine("(I:<-) Request received from dispatcher {0} - QueryAlive()      ", DateTime.Now);
					var ts = DateTime.Now - StartTime;

					return ts;
				}
				catch (Exception e)
				{
					Console.WriteLine("(I:<-) Error in QueryAlive. Reason: {0}", e.Message);

					throw new Exception(e.Message);
				}
			}
		}
	}
}

[yallie]

I did not turn on encryption explicit. Is it encrypted by default? How can I turn it off?

I believe yes, it's on by default. To turn it off, specify encryption: false in your protocol setup constructors. Using your sample code above, replace:

new TcpDuplexServerProtocolSetup(8012) => new TcpDuplexServerProtocolSetup(8012, null, false);
new TcpDuplexClientProtocolSetup() => TcpDuplexClientProtocolSetup(false);

Linux / Ubuntu Mate 16.04.1 LTS / Mono 4.6.1 / Zyan 2.8 / (same on Raspberry)

Have you tried this code on Mono for Windows?
I'll need some time to set up a linux box for testing.

[guehmann]

Don't hurry.

I never tried mono on Windows.

I'll implement it with turned of encryption and give you feedback.
Thanks.

[guehmann]

Hi Yallie,

you saved my day, great!!!

Turned off encryption an the times from the Raspberry are in milliseconds. So sending and receiving works very fast. For this solution its no problem with encryption disabled. Perhaps on a later stage in Raspberry Development I'll try to turn it on again.

Calling the agents from my dispatcher, it's the same behavior. The first "mono" agent throws the error, but it's no problem. I'll catch this exception and make one retry so i get my results.

Thanks a lot.
Best Jens.

If this is a little more stable, I'll make long term tests with dispatcher and agent. I'll tell you about.

Small appendum:
If a call my ubuntu/mono agent from a ubuntu/mono/raspberry i do not get the error with "channel sink", the other way round eighter. Must be a Windows .NET Problem perhaps.

[yallie]

Hello Jens,

glad to hear it helped with the encryption stuff!

Must be a Windows .NET Problem perhaps.

Windows to Windows connections work just fine in lots of my projects,
so I guess it's an interoperability issue between Windows and Mono.
I'm going to set up a virtual Linux box, perhaps using the Vagrant tool
so I can looks closer into the issue.

BTW, if by any chance you yourself use Vagrant and have a ready to use
vagrantfile for your version of Ubuntu and Mono, please let me know.
It'd save me some time figuring out how to set things up.

Regards, Alexey

[guehmann]

Ok, thank you.

[yallie]

Hello Jens,

I've installed Vagrant and set up Ubuntu 16.04.1 virtual box.
I couldn't find out how to install specific Mono version, so I've just installed the latest v4.6.2.
Then I've created a minimal console application that can act as a client and a server.

I tried running the app on Windows and connecting from Windows machine.
And I tried running app on my virtual Ubuntu box and connecting from Windows host.
Finally, I tried running the app on Ubuntu and connecting from the same Ubuntu box.
Either way, I see no errors even on my first call:

Here is my stripped down application code:

using System;
using System.Linq;
using Zyan.Communication;
using Zyan.Communication.Protocols.Tcp;

class Program
{
	static void Main(string[] args)
	{
		if (!args.Any())
		{
			RunServer();
			return;
		}

		RunClient(args.First());
	}

	public interface IAgent
	{
		void QueryAlive();
	}

	public class Agent : IAgent
	{
		public void QueryAlive()
		{
			Console.WriteLine("QueryAlive!");
		}
	}

	public static void RunServer()
	{
		var proto = new TcpDuplexServerProtocolSetup(8012, null, false);
		using (var host = new ZyanComponentHost("AgentService", proto))
		{
			host.RegisterComponent<IAgent, Agent>();
			Console.WriteLine("Server started. Press Enter to quit");
			Console.WriteLine("Hint: run 'test.exe tcpex://localhost:8012/AgentService' to connect.");
			Console.ReadLine();
		}
	}

	public static void RunClient(string url)
	{
		var proto = new TcpDuplexClientProtocolSetup(false);
		using (var conn = new ZyanConnection(url, proto))
		{
			var proxy = conn.CreateProxy<IAgent>();
			proxy.QueryAlive();

			Console.WriteLine("Connected. Press Enter to quit");
			Console.ReadLine();
		}
	}
}

Please have a look, perhaps I am missing something important.
Try compiling and running the app yourself and tell me if it breaks on the first call.
If it doesn't break out of the box, please try adding some project specifics until it does.

Also, I'm not sure if Mono version is important here, but it could be great if you
considered updating to the latest version of Mono, v4.6.2. Mono becomes gradually
better with each release as they replace their own code with the original MS code.

Please let me know how it goes.
Regards, Alexey

[guehmann]

Hi Yallie,

thanks a lot for your workout. I'll try it today. Just looked, my mono is 4.2.1 on Ubuntu VMWare Virtual machine and on Raspberry also.
On Windows I do not use mono, only .NET 4.5.2. I'll then try other version.
I'll inform you about it if I'm ready.

Regards Jens.

[yallie]

Hello Jens,

I didn't tested Mono on Windows, tried only Win.NET <-> Mono.Linux interaction.

UPD.
Tried with Mono/Windows (my version is 4.0.3):
Windows/Mono server — Windows/NET client
Windows/NET server — Windows/Mono client
Windows/Mono server — Windows/Mono client

Everything seems to be fine.

[guehmann]

Hi Yallie,

just finished testing. Everthing work fine with your code in console application on windows and linux with ubuntu/mono. Event on Ubuntu with Mono Gtk#.

Tested on Windows .NET 4.52 calling Mono Client on Virtual Machine with Ubuntu/Mono 4.6.2 and 4.2.1 (on Raspberry).

Even first call does not produce any error.

I discoverd, the namespace for the remoting interface must exactly match, else i get error the service ist not registerd.

Then i tried my Windows/GUI part to call your code.
I get the same error with 'Channel sink' on first call.
This is an WebApi 2.2 Asp.Net Core 1.0.1 code calling a windows service running topshelf/zyan with async methods. Perhaps this is the problem. But don't care, i have my workaround to intercept it.

This is part of my code in th windows service. Else I think I have the same code like you.

` public static async void AvailabilityCheck(int id)
{
Log2File.Info($"Verfügbarkeit der als aktiv angegebenen Terminals wird ausgeführt...");

        var agents = await AgentFactory.Many(Wrapper.WrapToMongoContext());
        foreach (var agent in agents.Where(a => a.IsEnabled == true))
        {
            try
            {
                var protocol = new TcpDuplexClientProtocolSetup(false);
                var url = protocol.FormatUrl(agent.Host, agent.Port, agent.Service);

                using (var conn = new ZyanConnection(url, protocol))
                {
                    var proxy = conn.CreateProxy<IAgent>();
                    var ts = proxy.QueryAlive();

                    Log2File.Info($"Verbindung zu Terminal '{agent.Name}' auf {agent.Host} erfolgreich hergestellt. Datenverbindung auf Port {agent.Port} " +
                        $"und Servicepunkt '{agent.Service}' erfolgreich eingerichtet. " +
                        $"Das Terminal ist seit {DurationHelper.ElapsedTime(ts.TotalMilliseconds)} aktiv.");
                }
            }
            // Fehlerbehandlung wegen bekanntem Fehler bei Statusabfrage von einem Mono Agent...
            catch (System.Runtime.Remoting.RemotingException re)
            {
                try
                {
                    var message = re.Message;
                    var protocol = new TcpDuplexClientProtocolSetup(false);
                    var url = protocol.FormatUrl(agent.Host, agent.Port, agent.Service);

                    using (var conn = new ZyanConnection(url, protocol))
                    {
                        var proxy = conn.CreateProxy<IAgent>();
                        var ts = proxy.QueryAlive();

                        Log2File.Info($"Verbindung zu Terminal '{agent.Name}' auf {agent.Host} erfolgreich hergestellt. Datenverbindung auf Port {agent.Port} " +
                            $"und Servicepunkt '{agent.Service}' erfolgreich eingerichtet. " +
                            $"Das Terminal ist seit {DurationHelper.ElapsedTime(ts.TotalMilliseconds)} aktiv.");
                    }
                }
                catch (Exception e)
                {
                    Log2File.Error($"Verbindung zu Terminal '{agent.Name}' nicht erfolgreich. Ursache: {e.Message}");
                }
            }
            catch (Exception e)
            {
                Log2File.Error($"Verbindung zu Terminal '{agent.Name}' nicht erfolgreich. Ursache: {e.Message}");
            }
        }

        Messenger.Send("admin@anytime.local",
            "Verfügbarkeitsprüfung Terminal",
            "Die Verfügbarkeitsüberprüfung der aktiven Terminals wurde beendet. " +
            "Überprüfen Sie das Protokoll für nähere Informationen zum Status der einzelnen Terminals.");
    }`

Thank you a lot for your work.
Regards Jens.

[yallie]

Hello Jens,

Then i tried my Windows/GUI part to call your code.
I get the same error with 'Channel sink' on first call.

Please provide more details.

Where do you run my test application as a server? On Ubuntu virtual box, right?
And you're trying to call it from a Windows GUI application? Is it WinForms? WPF?
Can you post a minimal compileable version of your program that reproduces
the problem when connected to my console server?

PS. I know you have a workaround, but it still feels uneasy as we don't know the cause.
My best guess is that your client app has some non-standard context sink or channel
registered, perhaps by the infrastructure (surely not in your code).

[guehmann]

Hi Yallie,

sorry about confusing info.

I run your application on windows as server, called by client from ubuntu/virtual machine and ubuntu/raspberry. Everything is ok.

Running the application on Windows/WPF as server and client work fine.

I run your application on ubuntu/virtual machine as server, called by client from ubuntu/raspberry and windows10/console-app. Everything is ok.
Also running the application on ubuntu/raspberry as server, all these constellations work fine.

What is not working is following:
I have an ASP.NET Core front-end calling an ASP.NET Core WebApi 2.2 Method running on IIS. This WebApi method connects as a client to a windows service (topshelf/zyan) running as server. The server itself (dispatcher) should open connection(s) as client to other zyan server over the net. (The dispatcher and the clients have both, server and client functionality implemented to receive requests and send requests by themself.)

I'll try to make a small VS2015 project over the day to reproduce the error.

Regards, Jens.

[guehmann]

Hi,

First of all wish you a merry christmas and do no work so hard over the days. All the best for you.

Made just a fresh solution with VS2015 attached.

There are 4 projects within this solution:

• Agent is a simple windows console application running a zyan server on port localhost:8020 waiting for a QueryAlive request coming in.

• Dispatcher is a windows server application registered a zyan host to receive request from a outside WebApi call or other instances. In one case receiving an "AliveRequest", opening a connection to other zyan host to query an alive request. This service is running on localhost:8012.
  Received this request the service is opening a connection to another zyan host (raspberry) on port (192.68.22.xx:8020) to query the alive status.

• RemoteObject hold the interface implementation of the remote object.

• WebApi, is a ASP.NET Core WebApi Controller with a simple method calling via a client call a zyan server to request the QueryAlive of the connected agents.

You do not really need an IIS to run the WebApi, just change with command line to the project folder of the WebApi and run 'dotnet run' . This will start a webserver on port 5000

You can use Postman from google to post web request to the api, or just use any explorer to call the simple WebApi Method: 'localhost:5000/zyan/QueryAlive'.

I coded some static ip-adresses in the dispatcher and agent. you must change them met your environment.

So this is just the complete project running on my environment, hope it will work with you.

Best regards, Jens.
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