I am trying to test socket communication on my laptop using python. However, I'm not sure why the connection is not being established? I keep getting error that the target machine is actively refusing connection. I am trying to use the same computer to run both the client and the server portion. The server is running fine but the client is the one not connecting. I think I have the hostname wrong (127.0.0.1) but not sure what Im supposed to be using? I also tried changing the server hostname to (0.0.0.0) and the IPV4 address for the hostname the client was to connect to but that didn't work either. Any help would be appreciated!
My code(server portion):
import socket
comms_socket =socket.socket()
comms_socket.bind(('127.0.0.1', 50000))
comms_socket.listen(10)
connection, address = comms_socket.accept()
while True:
print(connection.recv(4096).decode("UTF-8"))
send_data = input("Reply: ")
connection.send(bytes(send_data, "UTF-8"))
Client portion:
import socket
comms_socket = socket.socket()
comms_socket.connect(('127.0.0.1',50000))
while True:
send_data = input("Message: ")
comms_socket.send(bytes(send_data, "UTF-8"))
print(comms_socket.recv(4096).decode("UTF-8"))
Your code won't work with python 2.* , because of the differences in input(), raw_input(), bytes, etc. in python 3.* vs python 2.* . You'd have to minimally make the following changes to get it working with python 2.*. Otherwise, use python 3 to run your code:
Server program:
import socket
comms_socket =socket.socket()
comms_socket.bind(('127.0.0.1', 7000))
comms_socket.listen(10)
connection, address = comms_socket.accept()
while True:
print(connection.recv(4096).decode("UTF-8"))
send_data = raw_input("Reply: ") # Use raw_input() instead of input()
connection.send(send_data.encode("UTF-8"))
Client program:
import socket
comms_socket = socket.socket()
comms_socket.connect(('127.0.0.1',7000))
while True:
send_data = raw_input("Message: ")
comms_socket.send(send_data.encode("UTF-8"))
print(comms_socket.recv(4096).decode("UTF-8"))
If you want to use bytes as intended in your specific usecase, you should use bytesarray instead in python 2.6 or higher. Check this: the bytes type in python 2.7 and PEP-358
Related
I'm trying to create mockup telnet server (for some functional testing of existing code). Right now I only modified server welcome message and I was trying to read this message using client code, but it read method fails on timeout with no additional info. But with pudb debugger enabled it works most of the time...
I'm using virtualenv, with pudb and telnetsrv installed using pip. Python 2.7.12, ubuntu 16.04.
Server code:
import SocketServer
from telnetsrv.threaded import TelnetHandler
class MyHandler(TelnetHandler):
WELCOME = "HI from custom server"
class TelnetServer(SocketServer.TCPServer):
allow_reuse_address = True
server = TelnetServer(("0.0.0.0", 8023), MyHandler)
server.serve_forever()
Client code:
import telnetlib
HOST = '127.0.0.1'
PORT = 8023
# from pudb import set_trace; set_trace()
tn = telnetlib.Telnet(HOST, PORT)
data = tn.read_until("custom server", timeout=1)
print "Data: " + data
tn.close()
Client output:
$ python client.py
Data:
Client output with pudb enabled (with step-by-step execution)
$ python client.py
Data: HI from custom server
Of course when I execute shell telnet command, it all works fine:
$ telnet 127.0.0.1 8023
Trying 127.0.0.1...
Connected to 127.0.0.1.
Escape character is '^]'.
HI from custom server
Telnet Server>
I'd really appreciate any hints on how to debug this problem. Thanks!
Be sure there is actually connecting going on. To do that put edit your code to add tn.set_debuglevel(100) into your script to look like this:
import telnetlib
HOST = '127.0.0.1'
PORT = 8023
# from pudb import set_trace; set_trace()
tn = telnetlib.Telnet(HOST, PORT)
tn.set_debuglevel(100)
data = tn.read_until("custom server", timeout=1)
print "Data: " + data
tn.close()
This will ensure all the data is printed out so you can see what's going on.
My theory is, that you're not connecting, or that your data isn't actually outputting "custom server" and therefor it won't catch it, or your timeout is too low.
I am trying to connect to a server using python sockets. I am able to make a connection and fetch the response data. However, I want the socket communication to be interactive from the client side.
For instance, if I use netcat to connect to the server, the communication is interactive:
nc aa.bb.cc.dd 1234
Server greets you
I can enter the input here
Server responds to my input
However, when I make the connection using python sockets, all I receive is the greeting from the Server and program completes execution.
Here is the python code I am using:
#! /usr/bin/python
import os
import sys
import socket
host = "aa.bb.cc.dd"
port = 1234
remote_ip = socket.gethostbyname(host)
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((remote_ip, port))
print s.recv(1024)
I want to modify the above python program so that I can send inputs to the Server as well.
Thanks.
Usually you do
input_data = input("Enter something: ")
s.send(bytes(input_data,'utf-8'))
You could use a while loop to get user input, send to server, and get a response continuously.
while True:
print(str(s.receive(1024)))
toSend = input()
s.send(bytes(toSend, "utf-8"))
I'm trying to make a proof of concept tcp server and client with Python 3.4. Everything with network part works nice. I tried to make it interactive and get user input from the client and send it to the server. But when I try to use it as HTTP client (write a custom request in console and send it to the server) it failed to get a response. The problem is that input() function interprets \r\n\ as string. How can I tell to python to interpret them as a .
Example :
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(("www.google.com", 80))
user_input = input("Inser message: ") # GET / HTTP/1.1\r\n\r\n
sock.sendall(user_input.encode("utf-8"))
message = sock.recv(4096)
Thanks in advance for any suggestion.
You can use replace:
user_input = user_input.replace('\\r', '\r').replace('\\n', '\n')
I was trying to create a python socket server that could send and receive data, so I created a socket on the server using the code here:
import socket
serversocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
serversocket.bind(('', 1208))
serversocket.listen(5)
(client,(ip,port)) = serversocket.accept()
Then I tried to create a sample connection from my machine by going to command prompt and typing
telnet www.filesendr.com 1208
However, the console simply replies with "Could not open connection to the host, on port 1208...Connection failed." I went back over my code but couldn't identify the problem. Any help would be greatly appreciated.
I think part of the problem is that after you accept the connection you don't do anything else. Once the accept happens, you get to the end of the script, python exits and closes all open file handles (including the socket you just opened). If you want to be able to talk to yourself through telnet, try something like this:
import socket
import select
import sys
port = 1208
listener = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
listener.setsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR,1)
listener.bind(('',port))
listener.listen(128)
newSock, addr = listener.accept()
while True:
r,w,e = select.select([newSock,sys.stdin],[],[])
if newSock in r:
data = newSock.recv(4096)
sys.stdout.write(data)
if sys.stdin in r:
newSock.send(sys.stdin.readline())
i tried to do client and server and look what i do
#Server
import socket
Host=''
Port=305
OK=socket.socket()
OK.bind((Host,Port))
OK.listn(1)
OK.accept()
and another one for client
#Client
impot socket
Host='192.168.1.4'
Port=305
OK=socket.socket()
OK.connect((Host,Port))
First thing : for now every thing is ok but i want when client connect to server :
server print "Hello Admin" in client screen
second thing : i want make like input command ! like
COM=raw_input('enter you command system:')
then client enter dir for example then server print the result in client screen
Look here, this is a simple echo server written in Python.
http://ilab.cs.byu.edu/python/socket/echoserver.html
When you create a connection, the story isn't over. Now it's time to send data over the connection. Create a simple "protocol" (*) and use it to transfer data from client to server and/or back. One simple example is a textual protocol of commands separated by newlines - this is similar to what HTTP does.
(*) Protocol: an agreement between two parties on the format of their communication.
I think you might want to do something like this:
client, addr = OK.accept()
client.send("Hello Admin")
And then use
data = client.recv(1024)
to get data from the client.
If you want to get command input from the client, you just need to execute the commands the client sends and send the output back back to the client.
from commands import getoutput
client.send(getoutput(client.recv(1024)))
Thats about the easiest solution possible.
For Client:
import os
import sys
impot socket
Host=raw_input ("Please enter ip : ")
Port=raw_input ("please Enter port :")
OK=socket.socket()
OK.connect((Host,Port))
print " Enter Command")
cmd = raw_input()
os.system(cmd)
I think that your codes has an issue:
you seem to have OK = socket.socket(), but I think it should be:
OK = socket.socket(socket.AF_INET, socket.STREAM), which would help if your making a connection. And your server has a problem: OK.listn(1) should be OK.listen(1). And, don't forget about send() and recv().
#Client
import socket
Host='192.168.1.4'
Port=305
OK=socket.socket(socket.AF_INET, socket.STREAM)
OK.connect((Host,Port))
while True:
com = raw_input("Enter your command: ")
OK.send(com)
data = OK.recv(5000) #Change the buffer if you need to, I have it setup to run 5000
print "Received:\n" + data
which should work for the client
#Server
import socket
import os
Host=''
Port=305
OK=socket.socket(socket.AF_INET, socket.STREAM)
OK.bind((Host,Port))
OK.listen(1)
conn, addr = OK.accept()
while True:
data = conn.recv(2048) #Change the buffer if needed
if data == "":
break
r = os.system(data)
conn.send(str(r)) #Note this will send 0 or 1, 0 = ran, 1 = error
Note: These fixes would work for Windows, I don't know about Unix systems.*