/// <summary>

/// A 'kernel' is a program that runs and introspects the user's code.

/// https://jupyter-client.readthedocs.io/en/stable/kernels.html

/// </summary>

public class Kernel

{

private ConnInfo _conn;

private string _shellAddress;

private string _iopubAddress;

private bool _exit = false;

private KernelInfoHandler<KernelInfoRequest> _kernelInfoHandler;

private ExecuteHandler<ExecuteRequest> _executeHandler;

private ILoggerFactory _loggerFactory;

public Kernel(ConnInfo conn, ILoggerFactory loggerFactory)

{

_conn = conn;

// https://netmq.readthedocs.io/en/latest/router-dealer/

_shellAddress = $"@tcp://{conn.IP}:{conn.ShellPort}";

_iopubAddress = $"@tcp://{conn.IP}:{conn.IOPubPort}";

_loggerFactory = loggerFactory;

}

public void Start()

{

// catch CTRL+C as exit command

Console.CancelKeyPress += (s, e) =>

{

e.Cancel = true;

_exit = true;

};

using (var shell = new RouterSocket(_shellAddress))

using (var iopub = new PublisherSocket(_iopubAddress))

using (var poller = new NetMQPoller())

{

var iopubSender = new MessageSender(_conn.Key, iopub);

var shellSender = new MessageSender(_conn.Key, shell);

_kernelInfoHandler = new KernelInfoHandler<KernelInfoRequest>(iopubSender, shellSender);

_executeHandler = new ExecuteHandler<ExecuteRequest>(iopubSender, shellSender, _loggerFactory);

// Handler for messages coming in to the frontend

shell.ReceiveReady += (s, e) =>

{

var raw = e.Socket.ReceiveMultipartMessage();

var header = JsonConvert.DeserializeObject<Header>(raw[3].ConvertToString());

Console.WriteLine($"{header.MessageType}: [{raw.ToString()}]");

switch (header.MessageType)

{

case "kernel_info_request":

{

var message = new Message<KernelInfoRequest>(header, raw);

iopubSender.Send(message,

new Status { ExecutionState = StatusType.Idle },

MessageType.Status);

_kernelInfoHandler.Process(message);

}

break;

case "execute_request":

{

var message = new Message<ExecuteRequest>(header, raw);

iopubSender.Send(message,

new Status { ExecutionState = StatusType.Busy },

MessageType.Status);

_executeHandler.Process(message);

iopubSender.Send(message,

new Status { ExecutionState = StatusType.Idle },

MessageType.Status);

}

break;

}

};

poller.Add(shell);

poller.RunAsync();

// var heartbeat = new HeartBeat(conn);

Console.WriteLine($"Listening Shell {_shellAddress}");

Console.WriteLine($"Listening IOPub {_iopubAddress}");

// hit CRTL+C to stop the while loop

while (!_exit)

Thread.Sleep(100);

}

}

}