When the client tries to connect to the server it always raise an exception. I have disabled Windows firewall and my antivirus and I have also opened the port 50100 on the router configuration panel.
Server:
import socket
HOST = ''
PORT = 8882
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((HOST, PORT))
s.listen(1)
conn, addr = s.accept()
s.close()
Client:
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
host = 'localhost'
port = 50100
remote_ip = s.gethostbyname(host)
s.connect((remote_ip, port))
s.close()
Specify the correct remote port in the client (i.e., the same port as the in the server script).
# Client
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
host = 'localhost'
port = 8882
remote_ip = socket.gethostbyname(host)
s.connect((remote_ip, port))
s.close()
Related
I have a simple echo server that echos back whatever it receives. This works well for a single client request.
# echo-server.py
import socket
HOST = "127.0.0.1"
PORT = 65432
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.bind((HOST, PORT))
s.listen()
conn, addr = s.accept()
with conn:
print(f"Connected by {addr}")
while True:
try:
data = conn.recv(1024)
except KeyboardInterrupt:
print ("KeyboardInterrupt exception captured")
exit(0)
conn.sendall(data)
# echo-client.py
import socket
HOST = "127.0.0.1" # The server's hostname or IP address
PORT = 65432 # The port used by the server
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.connect((HOST, PORT))
s.sendall(b"Hello, world")
data = s.recv(1024)
print(f"Received {data!r}")
However, if I finish one client request, and do a second client request, the server no more echoes back. How can I solve this issue?
(base) root#40029e6c3f36:/mnt/pwd# python echo-client.py
Received b'Hello, world'
(base) root#40029e6c3f36:/mnt/pwd# python echo-client.py
On the server side, you need to accept connections in an infinite loop. This should work.
server.py
HOST = "127.0.0.1"
PORT = 65432
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.bind((HOST, PORT))
s.listen()
while True:
conn, addr = s.accept()
print(f"Connected by {addr}")
try:
data = conn.recv(1024)
except KeyboardInterrupt:
print ("KeyboardInterrupt exception captured")
exit(0)
conn.sendall(data)
So I was trying to figure out a way to use sockets to make a terminal-based chat application, and I managed to do it quite well. Because I could only test it on one computer, I didn't realize that it might not work on different computers. My code is as simple as this:
# Server
import socket
HOST = "0.0.0.0"
PORT = 5555
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.bind((HOST, PORT))
s.listen()
while True:
conn, addr = s.accept()
with conn:
print("Connected to", addr)
data = conn.recv(1024)
print("Received:", data.decode())
conn.sendall(data)
# Client
import socket
HOST = "192.168.0.14"
PORT = 5555
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.connect((HOST, PORT))
s.sendall(b"Hello this is a connection")
data = s.recv(1024)
print("Received:", data.decode())
I've tried changing the ip to 0.0.0.0, use gethostname a lot of other things, but it just doesn't work. The server is up and running, but the client can't connect. Can someone help me?
I believe that 0.0.0.0 means connect from anywhere which means that you have to allow port 5555 through your firewall.
Instead of 0.0.0.0 use localhost as the address in both the client and the server.
I just tested your code using localhost for the server and the client and your program worked.
server:
Connected to ('127.0.0.1', 53850)
Received: Hello this is a connection
client:
Received: Hello this is a connection
As you can see, all that I changed was the address on both the server and the client. If this doesn't work then there is something outside of your program that is preventing you from success. It could be a permissions issue or another program is listening on port 5555.
server.py
# Server
import socket
HOST = "0.0.0.0"
HOST = "localhost"
PORT = 5555
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.bind((HOST, PORT))
s.listen()
while True:
conn, addr = s.accept()
with conn:
print("Connected to", addr)
data = conn.recv(1024)
print("Received:", data.decode())
conn.sendall(data)
if __name__ == '__main__':
pass
client.py
# Client
import socket
HOST = "localhost"
PORT = 5555
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.connect((HOST, PORT))
s.sendall(b"Hello this is a connection")
data = s.recv(1024)
print("Received:", data.decode())
if __name__ == '__main__':
pass
I've got a TCP socket: the simplest client-server application.
First question: How can I generate a self-signed and non-self-signed SSL packet in Python?
Second question: How can I transfer SSL packets from the client to the server?
Programming language is python.
Server Code:
import socket
HOST = '127.0.0.1' # Standard loopback interface address (localhost)
PORT = 65432 # Port to listen on (non-privileged ports are > 1023)
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.bind((HOST, PORT))
s.listen()
conn, addr = s.accept()
with conn:
print('Connected by', addr)
while True:
data = conn.recv(1024)
if not data:
break
conn.sendall(data)
Client side code:
import socket
HOST = '127.0.0.1' # The server's hostname or IP address
PORT = 65432 # The port used by the server
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.connect((HOST, PORT))
s.sendall(b'Hello, world')
data = s.recv(1024)
print('Received', repr(data))
So i want to build simple Server-Client.
This server gets connections from clients (simple string), do my stuff, return answer, close the client connection and wait for another connections.
Client
import socket
client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
ip = '127.0.0.1'
port = 4500
address = (ip, port)
message = 'mymessage'
client = socket.socket()
client.connect(address)
client.sendall(message.encode('utf-8'))
Server
import socket
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
name = socket.gethostname()
ip = '127.0.0.1'
port = 4500
address = (ip, port)
server.bind(address)
server.listen(1)
print('Start listening on', ip, ':', port)
client, addr = server.accept()
print('Received connection from', addr[0], ':', addr[1])
while True:
data = client.recv(1024).decode('utf-8')
print('Received', data, 'from the client')
# DO something.....
client.send('Goodbye'.encode('utf-8'))
client.close()
break
So currently after the client get back the response from the server the server is close and i want my server to continue listening for another connections.
Simple, you need to add another loop, so that the server can always listen:
Server
import socket
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
name = socket.gethostname()
ip = '127.0.0.1'
port = 4500
address = (ip, port)
server.bind(address)
server.listen(1)
while True:
client, addr = server.accept()
print('Start listening on', ip, ':', port)
print('Received connection from', addr[0], ':', addr[1])
while True:
data = client.recv(1024).decode('utf-8')
print('Received', data, 'from the client')
# DO something.....
client.send('Goodbye'.encode('utf-8'))
client.close()
break
So i would like to create a small online game. (I am a complete noob with networking)
I got a server-client connection going if they are both on the same network but would need to do it over the internet. How do i do this?
server.py
import socket
s = socket.socket()
host = "0.0.0.0"
port = 5000
s.bind((host,port))
s.listen(5)
while True:
c, addr = s.accept()
print("Connection from", addr)
c.close()
client.py
import socket
s = socket.socket()
host = "192.168.1.66"
port = 5000
s.connect((host, port))
s.send(bytearray("Message", "ascii"))
I have tried using my public IP but i cannot connect.