From dc180abba90343d2a05490410bb2f48b67602521 Mon Sep 17 00:00:00 2001
From: Owen <owen@txv.io>
Date: Mon, 15 Dec 2025 22:11:57 -0500
Subject: [PATCH] Add test udp server and client

---
 udp_client.py | 49 +++++++++++++++++++++++++++++++++++++++++++
 udp_server.py | 58 +++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 107 insertions(+)
 create mode 100644 udp_client.py
 create mode 100644 udp_server.py

diff --git a/udp_client.py b/udp_client.py
new file mode 100644
index 0000000..2909d13
--- /dev/null
+++ b/udp_client.py
@@ -0,0 +1,49 @@
+import socket
+import sys
+
+# Argument parsing: Check if IP and Port are provided
+if len(sys.argv) != 3:
+    print("Usage: python udp_client.py <HOST_IP> <HOST_PORT>")
+    # Example: python udp_client.py 127.0.0.1 12000
+    sys.exit(1)
+
+HOST = sys.argv[1]
+try:
+    PORT = int(sys.argv[2])
+except ValueError:
+    print("Error: HOST_PORT must be an integer.")
+    sys.exit(1)
+
+# The message to send to the server
+MESSAGE = "Hello UDP Server! How are you?"
+
+# Create a UDP socket
+try:
+    client_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+except socket.error as err:
+    print(f"Failed to create socket: {err}")
+    sys.exit()
+
+try:
+    print(f"Sending message to {HOST}:{PORT}...")
+
+    # Send the message (data must be encoded to bytes)
+    client_socket.sendto(MESSAGE.encode('utf-8'), (HOST, PORT))
+
+    # Wait for the server's response (buffer size 1024 bytes)
+    data, server_address = client_socket.recvfrom(1024)
+
+    # Decode and print the server's response
+    response = data.decode('utf-8')
+    print("-" * 30)
+    print(f"Received response from server {server_address[0]}:{server_address[1]}:")
+    print(f"-> Data: '{response}'")
+
+except socket.error as err:
+    print(f"Error during communication: {err}")
+
+finally:
+    # Close the socket
+    client_socket.close()
+    print("-" * 30)
+    print("Client finished and socket closed.")
diff --git a/udp_server.py b/udp_server.py
new file mode 100644
index 0000000..89aea28
--- /dev/null
+++ b/udp_server.py
@@ -0,0 +1,58 @@
+import socket
+import sys
+
+# optionally take in some positional args for the port
+if len(sys.argv) > 1:
+    try:
+        PORT = int(sys.argv[1])
+    except ValueError:
+        print("Invalid port number. Using default port 12000.")
+        PORT = 12000
+else:
+    PORT = 12000
+
+# Define the server host and port
+HOST = '0.0.0.0'  # Standard loopback interface address (localhost)
+
+# Create a UDP socket
+try:
+    server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+except socket.error as err:
+    print(f"Failed to create socket: {err}")
+    sys.exit()
+
+# Bind the socket to the address
+try:
+    server_socket.bind((HOST, PORT))
+    print(f"UDP Server listening on {HOST}:{PORT}")
+except socket.error as err:
+    print(f"Bind failed: {err}")
+    server_socket.close()
+    sys.exit()
+
+# Wait for and process incoming data
+while True:
+    try:
+        # Receive data and the client's address (buffer size 1024 bytes)
+        data, client_address = server_socket.recvfrom(1024)
+
+        # Decode the data and print the message
+        message = data.decode('utf-8')
+        print("-" * 30)
+        print(f"Received message from {client_address[0]}:{client_address[1]}:")
+        print(f"-> Data: '{message}'")
+
+        # Prepare the response message
+        response_message = f"Hello client! Server received: '{message.upper()}'"
+
+        # Send the response back to the client
+        server_socket.sendto(response_message.encode('utf-8'), client_address)
+        print(f"Sent response back to client.")
+
+    except Exception as e:
+        print(f"An error occurred: {e}")
+        break
+
+# Clean up (though usually unreachable in an infinite server loop)
+server_socket.close()
+print("Server stopped.")