How to send a message from C# client to C++ server using ZeroMQ

Question

I am making an application that works in three different parts. One server running in C ++ and two clients running in C # and Python. The client connects to the server and sends a message.

To do this I have opted for ZeroMQ.

Because this is a POC, the code is simple.

Server Code (C++) (cppzmq)

zmq::context_t context{ 1 };
zmq::socket_t socket{ context, zmq::socket_type::rep };
socket.bind("tcp://*:5555");
zmq::message_t request;
socket.recv(request, zmq::recv_flags::none);

Python Client (pyzm)

context = zmq.Context()
socket = context.socket(zmq.REQ)
socket.connect("tcp://localhost:5555")
socket.send(b"Hello")

C# client (NetMQ)

using(var socket =  new RequestSocket())
{
    socket.Connect("tcp://localhost:5555");
    byte[] msg = Encoding.ASCII.GetBytes("HEllo");
    socket.SendFrame(msg);
 }

The connection between the Python client and the server is successful and the server receives the message sent by the client. But the connection between C # client and server is not correct. On the C # side it is assumed that you have successfully connected and transmitted the message, but the server does not reflect any changes (as if you did not receive a call).

What can be the cause?

Answer 1

for c# I used NetMQMessage. Does this work better for you? I use other options (no linger and timeout)

using (var client = new RequestSocket()) {
  
   client.Connect("tcp://192.168.1.216:8000");

   NetMQMessage msg = new NetMQMessage();
   msg.Append("my request string buffer", Encoding.UTF8);
   client.SendFrame(msg.ToString());

   var res_bytes = client.ReceiveFrameBytes();
   // add some function to transform bytes to string

}