We use the same approach as writing an echo client/server using IPv6. The only major difference is how the socket is created using IPv6 information.
Listing 12a shows an IPv6 echo server, as follows:
#!/usr/bin/env python # Python Network Programming Cookbook, Second Edition -- Chapter - 3 # This program is optimized for Python 2.7.12 and Python 3.5.2. # It may run on any other version with/without modifications. import argparse import socket import sys HOST = 'localhost' def echo_server(port, host=HOST): """Echo server using IPv6 """ for result in socket.getaddrinfo(host, port, socket.AF_UNSPEC, socket.SOCK_STREAM, 0, socket.AI_PASSIVE): af, socktype, proto, canonname, sa = result try: sock = socket.socket(af, socktype, proto) except socket.error as err: print ("Error: %s" %err) try: sock.bind(sa) sock.listen(1) print ("Server lisenting on %s:%s" %(host, port)) except socket.error as msg: sock.close() continue break sys.exit(1) conn, addr = sock.accept() print ('Connected to', addr) while True: data = conn.recv(1024) print ("Received data from the client: [%s]" %data) if not data: break conn.send(data) print ("Sent data echoed back to the client: [%s]" %data) conn.close() if __name__ == '__main__': parser = argparse.ArgumentParser(description='IPv6 Socket
Server Example') parser.add_argument('--port', action="store", dest="port",
type=int, required=True) given_args = parser.parse_args() port = given_args.port echo_server(port)
Listing 12b shows an IPv6 echo client, as follows:
#!/usr/bin/env python # Python Network Programming Cookbook, Second Edition -- Chapter - 3 # This program is optimized for Python 2.7.12 and Python 3.5.2. # It may run on any other version with/without modifications. import argparse import socket import sys HOST = 'localhost' BUFSIZE = 1024 def ipv6_echo_client(port, host=HOST): for res in socket.getaddrinfo(host, port, socket.AF_UNSPEC, socket.SOCK_STREAM): af, socktype, proto, canonname, sa = res try: sock = socket.socket(af, socktype, proto) except socket.error as err: print ("Error:%s" %err) try: sock.connect(sa) except socket.error as msg: sock.close() continue if sock is None: print ('Failed to open socket!') sys.exit(1) msg = "Hello from ipv6 client" print ("Send data to server: %s" %msg) sock.send(bytes(msg.encode('utf-8'))) while True: data = sock.recv(BUFSIZE) print ('Received from server', repr(data)) if not data: break sock.close() if __name__ == '__main__': parser = argparse.ArgumentParser(description='IPv6 socket
client example') parser.add_argument('--port', action="store", dest="port",
type=int, required=True) given_args = parser.parse_args() port = given_args.port ipv6_echo_client(port)
The server output is as follows:
$ python 13_12a_ipv6_echo_server.py --port=8800 Server lisenting on localhost:8800 ('Connected to', ('127.0.0.1', 56958)) Received data from the client: [Hello from ipv6 client] Sent data echoed back to the client: [Hello from ipv6 client]
The client output is as follows:
$ python 13_12b_ipv6_echo_client.py --port=8800 Send data to server: Hello from ipv6 client ('Received from server', "'Hello from ipv6 client'")
The following screenshot indicates the server and client output:
IPv6 Echo Server and Client