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MSight Tutorial: Building and Testing a UDP Server Node

A udp server node is a source node in MSight system that is setup, reading UDP packets from a specified port and publishing the received data to the pub/sub system. This short tutorial walks you through setting up a UDP Source Node in MSight, sending bytes via a simple UDP client, and verifying that the messages are correctly published and received within the MSight system.

📦 Prerequisites

Before beginning, ensure the following are installed:

  • MSight system installed
  • Docker (for running Redis)

MSight uses Redis as its pub/sub backend, so we need to start a Redis server before launching any nodes.

🚀 Step 1: Start Redis Using Docker

Run the following Docker command:

docker run -d --name msight-redis -p 6379:6379 redis

This launches Redis in a container and exposes it on port 6379 (default).

Verify it's running:

docker ps

You should see msight-redis in the list.

🚀 Step 2: Launch the MSight UDP Server Node

Now start a UDP server node that listens on port 5000 and publishes received bytes to the topic udp_topic.

msight_launch_udp_server -n udp_server_node -pt udp_topic --sensor-name test_udp --port 5000

Expected output:

2025-11-15 02:16:56,498 - local - udp_server_node - INFO :: Received data of size 22, publishing to udp_topic.

🧪 Step 3: Write a Test UDP Client (Python)

Create a file named test_udp_client.py:

import socket
import time

SERVER_HOST = "127.0.0.1"
SERVER_PORT = 5000
MESSAGE = b"hello from test client"

sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

while True:
    try:
        print(f"Sending: {MESSAGE!r} to {SERVER_HOST}:{SERVER_PORT}")
        sock.sendto(MESSAGE, (SERVER_HOST, SERVER_PORT))
        time.sleep(1)
    except KeyboardInterrupt:
        sock.close()

Run it:

python test_udp_client.py

👀 Step 4: Launch a Bytes Viewer Node (Subscriber)

msight_launch_bytes_viewer -n bytes_viewer -t udp_topic --filter-sensor-name test_udp

Output example:

2025-11-15 02:18:12,144 - local - bytes_viewer - INFO :: Bytes received, latency:  4 ms, sensor_name: test_udp
2025-11-15 02:18:12,144 - local - bytes_viewer - INFO :: Payload: b'hello from test client'

🎉 Congratulations!

You have successfully completed the MSight UDP server tutorial!