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Simple word game using TCP socket

I'm new to socket and python programming, and I'm trying to build a simple game between server and client. Basically server types in a word and the client tries to guess another word starting with the first two letters of the server's word.Example: Server:computer|Client:erase|Server:secondary|Client:rye
I've got a loop that takes messages from client and sends it back to it and vice versa:
#server.py
while True:
message_sent = input(str("Me : "))
conn.send(message_sent.encode())
message_received = conn.recv(1024).decode()
first = message_sent[:2]
last = message_received[-2:]
print(s_name, ":", message_received)
if first != last:
message = "wrong word entered "
conn.send(message.encode())
print("\n")
break
and client.py:
#client.py
while True:
message_received = s.recv(1024).decode()
print(s_name, ":", message_received)
message_sent = input(str("Me : "))
first = message_sent[:2]
last = message_received[-2:]
if first != last:
message = "wrong word typed "
s.send(message.encode())
print("\n")
break
s.send(message_sent.encode())
when I send an incorrect word to the server from the client I can get the "wrong word typed" but when I send it other way it just accepts the word and keeps going. What am I doing wrong here?

in the server add:
while True:
message_sent = input(str("Me : "))
conn.send(message_sent.encode())
message_received = conn.recv(1024).decode()
if message_received == "wrongword":
print('GAME OVER')
print('Winner is Server')
break
first = message_sent[:2]
last = message_received[-2:]
print(s_name, ":", message_received)
if first != last:
message = "wrongword"
conn.send(message.encode())
print("\n")
break
in the client:
while True:
message_received = s.recv(1024).decode()
if message_received == "wrongword":
print('GAME OVER')
print('Winner is Client')
break
print(s_name, ":", message_received)
message_sent = input(str("Me : "))
first = message_sent[:2]
last = message_received[-2:]
if first != last:
message = "wrongword"
s.send(message.encode())
print("\n")
break
s.send(message_sent.encode())

Python script stuck at queue.join()

I am trying to implement a server for handling many clients (from thenewboston python reverse shell tutorials). I have the exact same code but when i run the script it gets stuck at queue.join(). How to make it work? I am unable to figure it out.
Here is the code
import socket
import sys
import threading
from queue import Queue
NUMBER_OF_THREADS = 2
JOB_NUMBER = [1, 2]
queue = Queue()
all_connections = []
all_addresses = []
# thread 1
# create socket (allows two computers to connect)
def socket_create():
try:
global host # ip address of the server
global port # port is to identify the kind of data
global s
host = ''
port = 9999
s = socket.socket()
except socket.error as msg:
print("Socket creation error: " + str(msg))
return
# bind socket to port and wait for connection from client
def socket_bind():
try:
global host
global port
global s
print("Binding socket to port: " + str(port))
s.bind((host, port))
s.listen(5)
# 5 is the no. of conections that can be made before server starts rejecting other requests
except socket.error as msg:
print("Socket binding error: " + str(msg) + "\n" + "Retrying...")
socket_bind()
return
# accept connections from multiple clients and save to list
def accept_connections():
for c in all_connections:
c.close()
del all_connections[:]
del all_addresses[:]
while 1:
try:
conn, address = s.accept()
conn.setblocking(1)
all_connections.append(conn)
all_addresses.append(address)
print("\nConnection has been establish: " + address[0])
except:
print("Error accepting connections")
return
# thread 2
# custom command promt for sending commands remotely
def start_turtle():
while True:
cmd = input('turtle> ')
if cmd == 'list':
list_connections()
elif 'select' in cmd:
conn = get_target(cmd)
if conn is not None:
send_target_commands(conn)
else:
print("Command not recognized")
return
# listing all the connections with indexing in the custom promt
def list_connections():
results = ''
for i, conn in enumerate(all_connections):
try:
conn.send(str.encode(' '))
conn.recv(20480)
except:
del all_connections[i]
del all_addresses[i]
continue
results += str(i) + ' ' + str(all_addresses[i][0]) + ' ' + str(all_addresses[i][1]) + '\n'
print('-----Clients-----' + '\n' + results)
return
# select a target client
def get_target(cmd):
try:
target = cmd.replace('select ', '')
target = int(target)
conn = all_connections[target]
print("You are now connected to " + str(all_addresses[target][0]))
print(str(all_addresses[target][0]) + '> ', end="")
return conn
except:
print("Not a valid selection")
return None
return
# connect with remote target client
def send_target_commands(conn):
while True:
try:
cmd = input()
if len(str.encode(cmd)) > 0:
conn.send(str.encode(cmd))
client_response = str(conn.recv(20480), "utf-8")
print(client_response, end="")
if cmd == "quit":
break
except:
print("Connection was lost")
break
return
# create worker threads
def create_workers():
for _ in range(NUMBER_OF_THREADS):
t = threading.Thread(target=work)
t.daemon = True
t.start
return
# do the next job in the queue (one handles connections, other sends commands)
def work():
while True:
x = queue.get()
if x == 1:
socket_create()
socket_bind()
accept_connections()
if x == 2:
start_turtle()
queue.task_done()
return
# create jobs for later extracting them and assigning them to the threads
def create_jobs():
for x in JOB_NUMBER:
queue.put(x)
queue.join()
return
def main():
create_workers()
create_jobs()
if __name__ == '__main__':
main()

Since you are using infinite loops (while True) at start_turtle and (while 1) at accept_connections they are not returning.
Since they don't return the func work never calls queue.task_done(), so the queue stuck joining.
I'm afraid you need to do one of the following:
start both start_turtle and accept_connections in parallel processes or threads.
Be sure they should call the queue.task_done().
For instance, you may include the queue as parameter and call it before starting the infinite loops (second option).
def work():
while True:
x = queue.get()
if x == 1:
socket_create()
socket_bind()
accept_connections(queue) # call queue.task_done() there
if x == 2:
start_turtle(queue) # call queue.task_done() in start_turtle
return
def start_turtle(queue):
queue.task_done() # Join one item from the queue
while True:
cmd = input('turtle> ')
if cmd == 'list':
list_connections()
elif 'select' in cmd:
conn = get_target(cmd)
if conn is not None:
send_target_commands(conn)
else:
print("Command not recognized")
return
On the other hand, in your create_workers you don't call the start method of the thread so your workers didn't really start.
Perhaps this is a typo.
def create_workers():
for _ in range(NUMBER_OF_THREADS):
t = threading.Thread(target=work)
t.daemon = True
# t.start # Not starting the Thread
t.start() # You need to call the start method
return

python thread waits for input before it prints

I'm writing a socket communication program, I have a main thread, and another thread trying to sock.recv()
when it does recieve bytes, it works as it needs, it goes to the right function, which at the end prints, and then the thread listens again to bytes (as wanted).
the problem is that the program won't print until I press enter...
if it matters i'm getting input at the same time in the main thread but it shouldn't matter.
note - the bytes are sent like this:
int (4 bytes) - msg type (string to print is 2)
int (4 bytes) - length of text to print
string ( bytes) - actual text
full code:
import socket
import time
import struct
import threading
import sys
PORT = 54321
def try_to_connect(ip):
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM,
socket.IPPROTO_TCP)
sock.settimeout(1)
try:
sock.connect((ip, PORT))
return sock
except:
return False
def text_parse(text, msg_id):
byte_text = bytes(text, "utf-8")
return struct.pack("II%ds" % len(byte_text), msg_id, len(byte_text), byte_text)
def main(sock):
global file_name
print("connected succefuly. to run a command, write $<command> (no space)\nto request a file, enter file path.\nto exit this program enter exit.")
inputed_text = ''
while True:
inputed_text = input()
if inputed_text == '':
pass
elif inputed_text == "exit":
return
elif inputed_text[0] == "$":
sock.send(text_parse(inputed_text[1:], 0))
else:
file_name = inputed_text
sock.send(text_parse(inputed_text, 1))
def print_string(message, msg_len):
text = struct.unpack("%ds" % msg_len, message)[0].decode("utf-8")
sys.stdout.write(text)
sys.stdout.flush()
def copy_file(message):
global file_name
final_file = open(file_name, "wb")
final_file.write(message)
final_file.close()
def recieve_loop(sock):
while True:
try:
header = sock.recv(8)
if not header: break
msg_type = struct.unpack("I", header[:4])[0]
msg_len = struct.unpack("I", header[4:8])[0]
print(msg_type)
print(msg_len)
message = sock.recv(msg_len)
if msg_type == 2:
print_string(message, msg_len)
elif msg_type == 3:
copy_file(message)
except socket.timeout:
pass
if __name__ == "__main__":
print("welcome to remote desktop program.\nto connect to your computer, enter it's ip.\nto exit enter exit")
text_input = "b,kjhkf"
while True:
text_input = input()
if text_input == "exit":
exit()
else:
sock = try_to_connect(text_input)
if sock:
socket_recieve_thread = threading.Thread(target = recieve_loop, args = [sock])
socket_recieve_thread.start()
main(sock)
socket_recieve_thread.join()
else:
print("the computer is not online")

Python imports module but doesn't recognize it when i initiate it?

I honestly have no idea why this is happening, I assume due to it not being on stack-exchange it's a very n00by mistake on my part. so here's the error:
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
UnboundLocalError: local variable 'socket' referenced before assignment
tcpServer.py
import socket
def Main():
UID = 1001
sockets = []
users = [] ## create usernames list
sessionLimit = input("session Queue Limit: ")
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(('192.168.1.74', 12127))
s.listen(sessionLimit) ## listen for 1 connection at a time
while True:
c, addr = s.accept()
sockets.append(c)
users.append(c.recv(1024).decode('utf-8'))
print("Connection from " + str(addr))
data = c.recv(1024).decode('utf-8') ## recieve 1024 bytes from client at a time, and then decode it into utf-8
if not data:
break
temp == data
temp.split(" ")
if temp[0] == "//": ## check to see if user has sent command
if temp[1] == "msg":
for i in range(len(users)):
if users[i] == temp[2]:
sockets[i].send((" ".join(temp[::2])).encode('utf-8'))
else: ## else, send data to all users. Could just use s.sendall(data.encode('utf-8'))
for socket in sockets:
socket.send(data.encode('utf-8')) ## send to sockets[socket]
##print("From connected user: " + data)
##data = data.upper()
##print("Sending: " + data)
##c.send(data.encode('utf-8'))
## command listening
commands = input("-> ")
commands.split(" ")
if commands[0] == "exit":
c.close() ## close connection
elif commands[0] == "/msg":
for i in range(len(users)):
if users[i] == commands[1]:
sockets[i].send((" ".join(commands[::1])).encode('utf-8'))
"""
elif commands[0] == "/rename": ## dont implement yet, due to users[] length changing
for i in range(len(users)):
if users[i] == commands[1]:
sockets[i].send("<server_" + UID + "> rename " + commands[2].encode('utf-8'))
"""
c.close()
if __name__ == "__main__":
Main()
Thanks for any help !
- Jacob

The issue is that you're using the variable name socket in the context of your Main() function when you do the following code block:
for socket in sockets:
socket.send(data.encode('utf-8')) ## send to sockets[socket]
That's causing an naming issue with the socket library. If you change that to:
for sock in sockets:
sock.send(data.encode('utf-8')) ## send to sockets[socket]
It will start to work. I also had to indent your code differently to ensure it was all in the Main() function you set up, and had to ensure the input() was parsed as an int. For reference, here's the full code block working for me:
import socket
def Main():
UID = 1001
sockets = []
users = [] ## create usernames list
sessionLimit = int(input("session Queue Limit: "))
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(('192.168.1.74', 12127))
s.listen(sessionLimit) ## listen for 1 connection at a time
while True:
c, addr = s.accept()
sockets.append(c)
users.append(c.recv(1024).decode('utf-8'))
print("Connection from " + str(addr))
data = c.recv(1024).decode('utf-8') ## recieve 1024 bytes from client at a time, and then decode it into utf-8
if not data:
break
temp == data
temp.split(" ")
if temp[0] == "//": ## check to see if user has sent command
if temp[1] == "msg":
for i in range(len(users)):
if users[i] == temp[2]:
sockets[i].send((" ".join(temp[::2])).encode('utf-8'))
else: ## else, send data to all users. Could just use s.sendall(data.encode('utf-8'))
for sock in sockets:
sock.send(data.encode('utf-8')) ## send to sockets[socket]
##print("From connected user: " + data)
##data = data.upper()
##print("Sending: " + data)
##c.send(data.encode('utf-8'))
## command listening
commands = input("-> ")
commands.split(" ")
if commands[0] == "exit":
c.close() ## close connection
elif commands[0] == "/msg":
for i in range(len(users)):
if users[i] == commands[1]:
sockets[i].send((" ".join(commands[::1])).encode('utf-8'))
"""
elif commands[0] == "/rename": ## dont implement yet, due to users[] length changing
for i in range(len(users)):
if users[i] == commands[1]:
sockets[i].send("<server_" + UID + "> rename " + commands[2].encode('utf-8'))
"""
c.close()
if __name__ == "__main__":
Main()

Python can't communicate with subprocess of a Minecraft server

I'm trying to write a handler/controller for the Minecraft server. My problem is that I can't seem get writing and reading to work properly. When a client issues a command that uses the server class's method serverCom, the Minecraft server's text/log starts to come into the Python window/Python console and the connected client hangs. Also, it seems that after I use Popen, the Minecraft server doesn't really launch until I do write to the server (aka serverCom method). In case anyone is wondering, the Popen goes to a batch file that opens the .jar file. This is on Windows XP.
import subprocess
import os
import configobj
import socket
import threading
from time import sleep
config = configobj.ConfigObj("config.ini")
cHost = config["hostip"]
cPort = int(config["hostport"])
cBuffer = int(config["serverbuffer"])
cClients = int(config["numberofclients"])
cPassword = config["password"]
class server(object):
def __init__(self):
self.process = False
self.folder = "C:\\servers\\minecraft-danny"
self.max = configobj.ConfigObj("%s\\simpleserver.properties"%self.folder)["maxPlayers"]
def serverStart(self):
if not self.process:
self.process = subprocess.Popen("java -Xmx1024m -Xms1024m -jar minecraft_server.jar nogui", cBuffer, None, subprocess.PIPE, subprocess.PIPE, subprocess.STDOUT, cwd = self.folder)
return True
return False
def serverStop(self):
if self.process:
self.serverCom("stop")
self.process = False
return True
return False
def serverCom(self, text):
if self.process:
self.process.stdout.seek(2)
self.process.stdin.write("%s\n"%text)
self.process.stdin.flush()
self.process.stdout.flush()
return (str(self.process.stdout.readline()), True)
return ("", False)
def serverPlayers(self):
if self.process:
self.serverCom("list")
x = self.serverCom(" ")[0].split(":")[3].replace("\n","").replace(" ","")
if x == "":
x = 0
else:
x = len(x.split(","))
return (x, self.max)
return (0,self.max)
serv = server()
def client(cnct, adr):
global count
try:
dat = str(cnct.recv(cBuffer)).split(" ")
ans = False
if dat[0] == "start":
print "Client %s:%s started the MC Server....."%(adr[0], adr[1])
x = serv.serverStart()
sleep(1)
serv.serverCom(" ")
serv.serverCom(" ")
sleep(5)
if x:
ans = "Server is now online."
else:
ans = "Server is already online."
elif dat[0] == "stop":
print "Client %s:%s stopped the MC Server....."%(adr[0], adr[1])
x = serv.serverStop()
sleep(6)
if x:
ans = "Server is now offline."
else:
ans = "Server is already offline."
elif dat[0] == "commun":
print "Client %s:%s executed a command on the MC Server....."%(adr[0], adr[1])
serv.serverCom(" ".join(dat[1:]))
x = serv.serverCom(" ")
if x[1]:
ans = x[0]
else:
ans = "No return text, server is offline or not responding."
elif dat[0] == "players":
print "Client %s:%s recieved the player count from the MC Server....."%(adr[0], adr[1])
pc = serv.serverPlayers()
ans = "%s/%s"%(pc[0],pc[1])
elif dat[0] == "help":
print "Client %s:%s recieved the help list....."%(adr[0], adr[1])
ans = "__________\nstart - Starts the server.\nstop - Stops the server.\ncommun <command> - Writes to server's console.\nplayers - Returns player count.\nhelp - Shows this help.\nclose - Closes client connections.\n__________"
elif dat[0] == "close":
pass
else:
ans = "Command '%s' is not valid."%dat[0]
if ans:
cnct.send("PASS")
cnct.send("%s\n"%ans)
threading.Thread(target = client, args = (cnct, adr,)).start()
else:
cnct.send("DICN")
cnct.send("Connection to server closed.\n")
cnct.close()
print "Client %s:%s disconnected....."%(adr[0], adr[1])
if count:
count -= 1
except:
cnct.close()
print "Client %s:%s disconnected..... "%(adr[0], adr[1])
if count:
count -= 1
print "-MC Server Control Server v0.0.1 BETA-"
print "Starting up server....."
print "Connecting to socket....."
count = 0
sck = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sck.bind((cHost, cPort))
sck.listen(5)
print "Connected and listening on %s:%s....."%(cHost, cPort)
print "Setting up client listener, allowing %s clients to connect at a time....."%cClients
while True:
for x in range(cClients):
(cnct, adr) = sck.accept()
print "Client %s:%s connected....."%(adr[0], adr[1])
cnct.send("Welcome to MineCraft Server Control.\n\nPlease enter server control password.\n")
ps = str(cnct.recv(cBuffer))
if count < cClients:
if ps == cPassword:
cnct.send("CRRT")
cnct.send("%s was correct.\nIf you need help type 'help'."%ps)
count += 1
threading.Thread(target = client, args = (cnct, adr,)).start()
else:
cnct.send("WRNG")
cnct.send("%s wasn't the correct password, please try again."%ps)
cnct.close()
print "Client %s:%s rejected....."%(adr[0], adr[1])
else:
cnct.send("WRNG")
cnct.send("Too many clients connected to MineCraft Server Control")
cnct.close()
print "Client %s:%s rejected....."%(adr[0], adr[1])
sck.close()

I have no idea how a Minecraft server works, but there are a number of problems with your code:
You are redirecting stderr to stdout from the created Java process, then expecting a line response from the server. This could be the reason that the Minecraft server is not starting, since it would block on a stderr write (depending on how Windows XP handles it). Additionally, any stderr write (e.g. log write) will destroy any structured responses you may be waiting for.
You are reading with sock.recv(N) and then assuming that you get the whole chunk (e.g. password). This is not how TCP works, you may very well get just one character back (especially true if the user types the password interactively e.g. in a Telnet prompt).
You are flushing the stdout of the subprocess, which is your input stream. You probably want to flush the stdin of the subprocess. Flushing an input stream makes no sense, it is the output stream that determines when to flush.