Add IPv6 support and HTTP server changes

Switch server binding and public IP detection to IPv6: BIND_IP now defaults to '::', public IP fetched from api64.ipify.org with a '::1' fallback, and IPv6 addresses are formatted with brackets for endpoints. Introduce format_host helper and use formatted endpoints for OPC UA (ENDPOINT/PUBLIC_ENDPOINT). Add IPv6HTTPServer (address_family=AF_INET6) and use it for the health HTTP server. Update printed server name and status messages to reflect IPv6. Minor refactor: import socket and adjust HTTP start message to show bracketed public host.

csv_opcua_server.py

@@ -1,5 +1,6 @@
 import asyncio
 import threading
+import socket
 from http.server import HTTPServer, BaseHTTPRequestHandler
 
 import pandas as pd
@@ -9,29 +10,42 @@ from asyncua import Server, ua
 # =========================
 # CONFIGURATION
 # =========================
-BIND_IP = "0.0.0.0"
+BIND_IP = "::"            # IPv6 wildcard
 OPCUA_PORT = 4840
 HTTP_PORT = 7860
 CSV_FILE = "data.csv"
 ROW_INTERVAL = 2  # seconds
 
 # =========================
-# PUBLIC IP DETECTION
+# PUBLIC IP DETECTION (IPv6)
 # =========================
 def get_public_ip():
     try:
-        return requests.get("https://ipinfo.io/ip", timeout=5).text.strip()
+        # This returns IPv6 if available
+        return requests.get("https://api64.ipify.org", timeout=5).text.strip()
     except Exception:
-        return "127.0.0.1"
+        return "::1"
 
 PUBLIC_IP = get_public_ip()
 
-ENDPOINT = f"opc.tcp://{BIND_IP}:{OPCUA_PORT}/csv-opcua-server/"
-PUBLIC_ENDPOINT = f"opc.tcp://{PUBLIC_IP}:{OPCUA_PORT}/csv-opcua-server/"
+# Wrap IPv6 in brackets for URL usage
+def format_host(ip):
+    if ":" in ip:
+        return f"[{ip}]"
+    return ip
+
+FORMATTED_BIND = format_host(BIND_IP)
+FORMATTED_PUBLIC = format_host(PUBLIC_IP)
+
+ENDPOINT = f"opc.tcp://{FORMATTED_BIND}:{OPCUA_PORT}/csv-opcua-server/"
+PUBLIC_ENDPOINT = f"opc.tcp://{FORMATTED_PUBLIC}:{OPCUA_PORT}/csv-opcua-server/"
 
 # =========================
-# SIMPLE HTTP SERVER
+# IPV6 HTTP SERVER
 # =========================
+class IPv6HTTPServer(HTTPServer):
+    address_family = socket.AF_INET6
+
 class HealthHandler(BaseHTTPRequestHandler):
     def do_GET(self):
         self.send_response(200)
@@ -43,24 +57,23 @@ class HealthHandler(BaseHTTPRequestHandler):
         return
 
 def start_http_server():
-    httpd = HTTPServer((BIND_IP, HTTP_PORT), HealthHandler)
-    print(f"HTTP server running on http://{PUBLIC_IP}:{HTTP_PORT}")
+    httpd = IPv6HTTPServer((BIND_IP, HTTP_PORT), HealthHandler)
+    print(f"HTTP server running on http://{FORMATTED_PUBLIC}:{HTTP_PORT}")
     httpd.serve_forever()
 
 # =========================
 # MAIN ASYNC OPC UA SERVER
 # =========================
 async def main():
-    # Load CSV
     df = pd.read_csv(CSV_FILE)
     if df.empty:
         raise ValueError("CSV file is empty")
 
-    # Create OPC UA server
     server = Server()
     await server.init()
+
     server.set_endpoint(ENDPOINT)
-    server.set_server_name("Public CSV OPC UA Async Server")
+    server.set_server_name("IPv6 CSV OPC UA Async Server")
 
     uri = "http://example.org/public-csv-opcua"
     idx = await server.register_namespace(uri)
@@ -68,7 +81,6 @@ async def main():
     objects = server.nodes.objects
     csv_obj = await objects.add_object(idx, "CSV_Data")
 
-    # Create variables
     variables = {}
     for col in df.columns:
         var = await csv_obj.add_variable(
@@ -81,7 +93,7 @@ async def main():
         variables[col] = var
 
     print("====================================")
-    print(" OPC UA SERVER RUNNING (ASYNC)")
+    print(" OPC UA SERVER RUNNING (IPv6)")
     print(f" Internal bind : {ENDPOINT}")
     print(f" Public access : {PUBLIC_ENDPOINT}")
     print(f" Publishing 1 row every {ROW_INTERVAL} seconds")
@@ -107,8 +119,5 @@ async def main():
 # START EVERYTHING
 # =========================
 if __name__ == "__main__":
-    # Start HTTP server in background thread
     threading.Thread(target=start_http_server, daemon=True).start()
-
-    # Start async OPC UA server
     asyncio.run(main())