Develop Reference

Python client socket not receiving data from TCP server

I'm trying to build a fake money transfer program with sockets in python. Everything is working perfectly except the "name" and "amount" transfer from the server to the client. When someone clicks receive on the client interface, the server is supposed to send the client the name of the person who sent the money and the amount. The problem is that the client is not receiving the data sent from the server. When you click the "receive" button, the interface just freezes then crashes. From the debugging I've done, I'm pretty sure the server is sending the name and amount, but the client is not receiving it. I honestly have no idea why it's not working. Everything I did should work like it has numerous other times throughout the program. This one has got me stumped.
Any help would be great. Thanks! 😁
[CODE]
Server.py:
import socket
import threading
HOST = '192.168.1.6'
PORT = 9090
def client_fun(client, addr):
global transfers
print(f"{addr} just connected!")
connected = True
while connected:
msg = client.recv(1024).decode('utf-8')
if msg == "RECEIVE_CHECK":
usrn = client.recv(1024).decode('utf-8')
transfers_ = open("transfers.txt", "r")
transfers = str(transfers_.readlines())
transfers = transfers.split("+")
transfers[0] = transfers[0].replace("[", "")
transfers[0] = transfers[0].replace("'", "")
transfers.pop()
names = []
for tran in transfers:
tran_ = tran.split("-")
i = 0
while i <= len(tran):
names.append(tran_[2])
i += 1
if usrn in names:
client.send("OK".encode('utf-8'))
else:
client.send("NO".encode('utf-8'))
if usrn in names:
for tran in transfers:
tran_ = tran.split("-")
if usrn == tran_[2]:
name = str(tran_[0])
amount = str(tran_[1])
client.send(name.encode('utf-8'))
client.send(amount.encode('utf-8'))
account_file = usrn + "_" + "account.txt"
account_r = open(account_file, "r")
account_r = str(account_r.readlines())
account_r = account_r.replace(']', '')
account_r = account_r.replace('[', '')
account_r = account_r.replace("'", "")
try:
account_r = int(account_r)
except:
print("Can't Convert Str to Int!")
break
new_amount = int(tran_[1]) + account_r
account_w = open(account_file, "w")
account_w.write(str(new_amount))
account_w.close()
tran = tran + "+"
transFers_ = open("transfers.txt", "r")
transFers = str(transFers_.readlines())
transFers_.close()
transFers = transFers.replace(']', '')
transFers = transFers.replace('[', '')
transFers = transFers.replace("'", "")
transFers = transFers.replace(tran, '')
transFers_ = open("transfers.txt", 'w+')
transFers_.write(transFers)
transFers_.close()
print("Excepted!")
else:
print("Nothing Here!")
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.bind((HOST, PORT))
server.listen()
print("Server is listening!")
while True:
c_socket, address = server.accept()
thread = threading.Thread(target=client_fun, args=(c_socket, address))
thread.start()
Client.py:
import socket
HOST = '192.168.1.6'
PORT = 9090
socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
def receive(usrn):
socket.send("RECEIVE_CHECK".encode('utf-8'))
socket.send(usrn.encode('utf-8'))
c = socket.recv(1024).decode('utf-8')
if c == "OK":
try:
print("Trying to except....")
name = socket.recv(2000).decode('utf-8')
amount = socket.recv(2000).decode('utf-8')
print("Excepted!")
messagebox.showwarning("Continue?", f"{name} has sent you ${amount}", icon="question")
messagebox.showwarning("Info", f"${amount} has just been transferred to your account!", icon="info")
menu(usrn)
except:
print("Error!")
else:
print("Nothing Today!")

proxy server with python

i have an university project with python which i have to write a proxy server that waits for a request from a client and then connects the client to the server. i searched the net and found an already-written code from this site:
https://www.geeksforgeeks.org/creating-a-proxy-webserver-in-python-set-1/
so i used it and made some changes in the code and add the public server and port to it
but when i run it i get this error:
line 33, in main
request = conn.recv(4096)
NameError: name 'conn' is not defined
so i'm not very familiar with sockets and python so if there are obvious mistakes in the code i would be happy if u guys could explain them in a very basic way so my amateur butt would understand it lol
this is the code:
import signal
import socket
import threading
class Proxy:
def __init__(self):
# creating a tcp socket
self.serverSocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
# reuse the socket
self.serverSocket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
self.ip = 'localhost'
self.port = 8080
self.serverSocket.bind((self.ip, self.port))
self.serverSocket.listen(10)
self.__clients = {}
def shutdown(self):
# shutdown on cntrl c
signal.signal(signal.SIGINT, self.shutdown)
def multirequest (self):
while True:
# establish the connection
(clientSocket, client_address) = self.serverSocket.accept()
d = threading.Thread(name=self._getclientname(client_address),
target=self.proxy_thread,
args=(clientSocket, client_address))
d.setDaemon(True)
d.start()
def main(self, conn):
# get the request from browser
request = conn.recv(4096)
# parse the first line
first_line = request.split('\n')[0]
# get url
url = first_line.split(' ')[1]
http_pos = url.find("://")
if http_pos == -1:
temp = url
else:
temp = url[(http_pos + 3):]
webserver = ""
port = -1
port_pos = temp.find(":")
# find end of web server
webserver_pos = temp.find("/")
if webserver_pos == -1:
webserver_pos = len(temp)
if port_pos == -1 or webserver_pos < port_pos:
# default port
port = 80
webserver = temp[:webserver_pos]
else: # specific port
port = int((temp[(port_pos + 1):])[:webserver_pos - port_pos - 1])
webserver = temp[:port_pos]
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.settimeout(1)
s.connect((webserver, port))
s.sendall(request)
while 1:
# receive data from web server
data = s.recv(4096)
if len(data) > 0:
conn.send(data) # send to browser/client
else:
break
p = Proxy()
p.main()

In python, the common pattern for executables is like this:
def main(): # Or whatever name you want to use
"""Your code here"""
# If you are importing the code, the condition will evaluate to false.
if __name__ == "__main__":
main()
Have in mind that you can use whatever function name you want.

You need to put your code inside of a class like this. Any variables you plan to use through your code, define inside of the __init__ method, this could be for example your self.serverSocket, ip, port number, etc.
The init method is deigned to run once, once you create an instance of the class, it usually stores variables. The main method or any other methods you define, would be where you put the rest of your code.
import signal
import socket
import threading
class proxy():
def __init__(self):
# creating a tcp socket
self.serverSocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
# reuse the socket
self.serverSocket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
self.your_ip = "127.0.0.1" # loop back address
self.your_port = 80 # use a port thats open like port 80
def shutdown(self):
# add your signal shutdown code here
pass
def main(self):
# shutdown on cntrl c
signal.signal(signal.SIGINT, self.shutdown)
self.serverSocket.bind((self.your_ip, self.your_port))
self.serverSocket.listen(10)
self.__clients = {}
while True:
# establish the connection
(clientSocket, client_address) = self.serverSocket.accept()
d = threading.Thread(name=self._getClientName(client_address),
target=self.proxy_thread,
args=(clientSocket, client_address))
d.setDaemon(True)
d.start()
# get the request from browser
request = conn.recv(4096)
# parse the first line
first_line = request.split('\n')[0]
# get url
url = first_line.split(' ')[1]
http_pos = url.find("://")
if http_pos == -1:
temp = url
else:
temp = url[(http_pos + 3):]
port_pos = temp.find(":")
# find end of web server
webserver_pos = temp.find("/")
if webserver_pos == -1:
webserver_pos = len(temp)
webserver = ""
port = -1
if port_pos == -1 or webserver_pos < port_pos:
# default port
port = 80
webserver = temp[:webserver_pos]
else: # specific port
port = int((temp[(port_pos + 1):])[:webserver_pos - port_pos - 1])
webserver = temp[:port_pos]
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.settimeout(1)
s.connect((webserver, port))
s.sendall(request)
while 1:
# receive data from web server
data = s.recv(4096)
if len(data) > 0:
conn.send(data) # send to browser/client
else:
break
p = proxy()
p.main()

I successful make a local python proxy via socket module: https://github.com/wayne931121/Python_Proxy_Server/blob/main/Proxy.py
It can run http and https request.
Code:
#!/usr/bin/env python
# coding: utf-8
# In[ ]:
# 參考資料
# https://docs.python.org/3/library/socket.html
# https://stackoverflow.com/questions/24218058/python-https-proxy-tunnelling
# https://stackoverflow.com/questions/68008233/proxy-server-with-python/73851150#73851150
import sys
#import ssl
import time
import signal
import socket
#import certifi
import threading
with open("log.txt", "w") as f:
f.write("")
def signal_handler(sig, frame):
print('Proxy is Stopped.')
sys.exit(0)
def write(*content, prt=False):
if prt :
if len(content[0])<100:
print(*content)
else:
print("This message is too long not print in cmd but will store at log.txt.")
if type(content[0])==bytes:
content = b" ".join(content)
else:
content = bytes(" ".join(content), encoding="utf-8")
with open("log.txt", "ab") as f:
f.write(content+b"\n")
class Proxy:
def __init__(self):
self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) # creating a tcp socket
self.sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) # reuse the socket
self.ip = "127.0.0.1"
self.port = 8080
# self.host = socket.gethostbyname(socket.gethostname())+":%s"%self.port
self.sock.bind((self.ip, self.port))
self.sock.listen(10)
print("Proxy Server Is Start, See log.txt get log.")
print("Press Ctrl+C to Stop.")
start_multirequest = threading.Thread(target=self.multirequest)
start_multirequest.setDaemon(True)
start_multirequest.start()
while 1:
time.sleep(0.01)
signal.signal(signal.SIGINT, signal_handler)
def multirequest(self):
while True:
(clientSocket, client_address) = self.sock.accept() # establish the connection
client_process = threading.Thread(target=self.main, args=(clientSocket, client_address))
client_process.setDaemon(True)
client_process.start()
def main(self, client_conn, client_addr): # client_conn is the connection by proxy client like browser.
origin_request = client_conn.recv(4096)
request = origin_request.decode(encoding="utf-8") # get the request from browser
first_line = request.split("\r\n")[0] # parse the first line
url = first_line.split(" ")[1] # get url
http_pos = url.find("://")
if http_pos == -1:
temp = url
else:
temp = url[(http_pos + 3):]
webserver = ""
port = -1
port_pos = temp.find(":")
webserver_pos = temp.find("/") # find end of web server
if webserver_pos == -1:
webserver_pos = len(temp)
if port_pos == -1 or webserver_pos < port_pos: # default port
port = 80
webserver = temp[:webserver_pos]
else: # specific port
port = int(temp[(port_pos + 1):])
webserver = temp[:port_pos]
write("Connected by", str(client_addr))
write("ClientSocket", str(client_conn))
write("Browser Request:")
write(request)
server_conn = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_conn.settimeout(1000)
try:
server_conn.connect((webserver, port)) # "server_conn" connect to public web server, like www.google.com:443.
except: # socket.gaierror: [Errno 11001] getaddrinfo failed
client_conn.close()
server_conn.close()
return
if port==443:
client_conn.send(b"HTTP/1.1 200 Connection established\r\n\r\n")
client_conn.setblocking(0)
server_conn.setblocking(0)
write("Connection established")
# now = time.time()
client_browser_message = b""
website_server_message = b""
error = ""
while 1:
# if time.time()-now>1: # SET TIMEOUT
# server_conn.close()
# client_conn.close()
# break
try:
reply = client_conn.recv(1024)
if not reply: break
server_conn.send(reply)
client_browser_message += reply
except Exception as e:
pass
# error += str(e)
try:
reply = server_conn.recv(1024)
if not reply: break
client_conn.send(reply)
website_server_message += reply
except Exception as e:
pass
# error += str(e)
write("Client Browser Message:")
write(client_browser_message+b"\n")
write("Website Server Message:")
write(website_server_message+b"\n")
# write("Error:")
# write(error+"\n")
server_conn.shutdown(socket.SHUT_RDWR)
server_conn.close()
client_conn.close()
return
server_conn.sendall(origin_request)
write("Website Host Result:")
while 1:
# receive data from web server
data = server_conn.recv(4096)
try:
write(data.decode(encoding="utf-8"))
except:
write(data)
if len(data) > 0:
client_conn.send(data) # send to browser/client
else:
break
server_conn.shutdown(socket.SHUT_RDWR)
server_conn.close()
client_conn.close()
Proxy()

Execute a functions remotely with python 3

I am pretty new to python and I had a script idea:
You have a listener which is waiting for functions and a client script which sends instructions to the server and in this case instructions are functions.
Like that I could execute functions code from the client on the other computer
I tried pickle but I can't figure out if it's working with functions
Shall I use Sockets or something else ?
here is the server code:
import socket
import time
HEADER_LENGHT = 10
IP = socket.gethostname()
PORT = 1234
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((IP, PORT))
s.listen(5)
while True:
clientsocket, address = s.accept()
print(f"Connection from {address} has been established ! ")
while True:
full_msg = b''
new_msg = True
while True:
msg = s.recv(16)
if new_msg:
print(f"New message lenght: {msg[:HEADERSIZE]}")
msglen = int(msg[:HEADERSIZE])
new_msg = False
full_msg += msg
if len(full_msg)- HEADERSIZE == msglen:
print("full msg recvd")
print(full_msg[HEADERSIZE:])
d = pickle.loads(full_msg[HEADERSIZE:])
print(d)
new_msg = True
full_msg = b''
print(full_msg)
The client code :
import socket
HEADERSIZE = 10
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((socket.gethostname(), 1235))
while True:
full_msg = b''
new_msg = True
while True:
msg = s.recv(16)
if new_msg:
print(f"New message lenght: {msg[:HEADERSIZE]}")
msglen = int(msg[:HEADERSIZE])
new_msg = False
full_msg += msg.decode("utf-8")
if len(full_msg)- HEADERSIZE == msglen:
print("full msg recvd")
print(full_msg[HEADERSIZE:])
new_msg = True
full_msg = b''
print(full_msg)
Here is the function code:
def generate(target, apikey, nbfriendly, nbteacher, nbleader, accounts):
acc_list = accounts
jsonFile = open("config.json", "r")
data = json.load(jsonFile)
lines_count = 0
if nbfriendly == "":
nbfriendly = 10
if nbteacher == "":
nbteacher = 10
if nbleader == "":
nbleader = 10
if apikey == "":
apikey = (data['steamWebAPIKey'])
if target == "":
target = (data['target'])
for l in accounts:
lines_count = lines_count + 1
conn = sqlite3.connect("accounts.sqlite")
c = conn.cursor()
max = accounts.count("\n")
counter = 0
print(accounts)
accounts = accounts.replace(":", " ")
accounts = accounts.replace("\n", " ")
accounts.split()
print(accounts)
splitted = accounts.split()
while counter < max:
username = splitted[counter]
password = splitted[(counter + 1)]
c.execute(
"INSERT INTO accounts (username, password, sharedSecret, lastCommend, operational) VALUES (? , ?, ?, ? , ?)",
(username, password, blank, mone, one)
)
conn.commit()
counter += 2
nbfriendly = int(nbfriendly)
nbteacher = int(nbteacher)
nbleader = int(nbleader)
target = str(target)
(data['commend']['friendly']) = nbfriendly
(data['commend']['teaching']) = nbteacher
(data['commend']['leader']) = nbleader
(data['target']) = target
(data['steamWebAPIKey']) = apikey
data = json.dumps(data, indent=4)
jsonFile.close()
with open('config.json', 'w') as outfile:
outfile.write(data)
outfile.close()

I'm not sure your code for sending messages using socket is correct (I don't see where you're sending bytes).
Concerning pickle is is indeed possible to use it as a function. Plus, the good thing is that it is dumped as a bytes object, so you don't even need to cast it before sendding it with sockets.
On the client side:
import pickle
def f(n):
return n * f(n - 1) if n else 1
to_send = pickle.dumps(f)
# Send to_send using sockets then
Then, on the server side, the only thing you need is to load the function:
import pickle
f = pickle.loads(received)
Since everything is an object in Python, you can use the exact same method to send the function's arguments using sockets and pickle.

How can I send a HTML page which contains pictures?

I've written a TCP server, which functions perfectly with web pages which only contain text, but I cant seem to send HTML files which contain pictures. How am I supposed to do it?
DIR = "D:/wwwroot/"
SERVER = ("server_address", 8820) #server_address replaced with my IP
PHRASE_CHART = "D:/wwwroot/phrase_chart.txt"
CONTENT_TYPE_CHART = "D:/wwwroot/content_type_chart.txt"
DEFAULT_PAGE = "D:/wwwroot/main.html"
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_socket.bind(SERVER)
client_counter = 0
while client_counter <= 10:
server_socket.listen(1)
(client_socket, client_address) = server_socket.accept()
client_counter += 1
while True:
try:
request = client_socket.recv(1024)
request = request[0:request.find("/r/n/r/n")]
if request[0:3] == "GET":
file_name = request[5: request.find("HTTP/1.1") - 1]
if os.path.isfile(DIR + file_name):
page = open(DIR + file_name)
data = ""
for line in page:
data += line
client_socket.send(data)
elif file_name == "":
page = open(DEFAULT_PAGE)
data = ""
for line in page:
data += line
client_socket.send(data)
else:
client_socket.send("")
else:
client_socket.close()
except socket.error:
break
client_socket.close()
server_socket.close()

Python proxy - Need help to send HTTP header to the browser

I'm making a proxy for my project and I'm trying to send to the browser (Firefox) an HTTP header to continue the "Conversation" between me(Proxy server) and the browser. The issue is: when I'm refreshing any page, the page Keeping loading. I use socket and select for the proxy:
import socket, select
#Sending a message for the waiting list
def send_Waiting_Messages(wlist):
for msg in messages_to_send:
clientSocket, data = msg
if clientSocket in wlist:
clientSocket.send('HTTP/1.1 200 OK\r\nContent-Type: text/html\r\n\r\n')
messages_to_send.remove(msg)
serverSocket = socket.socket()
serverSocket.bind(('0.0.0.0',8080))
serverSocket.listen(10)
open_client_sockets = []
messages_to_send = []
while True:
rlist, wlist, xlist = select.select([serverSocket] + open_client_sockets, open_client_sockets, [])
for currentSocket in rlist:
if currentSocket is serverSocket:
newSocket, addr = serverSocket.accept()
open_client_sockets.append(newSocket)
else:
data = currentSocket.recv(1024)
if data == "":
open_client_sockets.remove(currentSocket)
print 'Conn is closed'
else:
print data
messages_to_send.append((currentSocket, 'Hello, ' + data))
send_Waiting_Messages(wlist)
These lines:
clientSocket.send('HTTP/1.1 200 OK\r\n')
clientSocket.send('Content-Type: text/html\r\n\r\n')
are for sending the header.
Thanks for helpers!!

notice that every the send_Waiting_Messages function is sending the same response to all of your connected clients. I reccomend to replace it with the basic send function when the socket is in the wlist.
This will probably work
import socket, select
serverSocket = socket.socket()
serverSocket.bind(('0.0.0.0',8080))
serverSocket.listen(10)
open_client_sockets = []
while True:
rlist, wlist, xlist = select.select([serverSocket] + open_client_sockets, open_client_sockets, [])
for currentSocket in rlist:
if currentSocket is serverSocket:
newSocket, addr = serverSocket.accept()
open_client_sockets.append(newSocket)
else:
data = currentSocket.recv(2048)
if data == "":
open_client_sockets.remove(currentSocket)
print 'Conn is closed'
else:
print data
content_to_send = "The content that you want to send"
currentSocket.send("HTTP/1.1 200 OK\r\nContent-Type: text/html\r\nContent-Length:"+str(len(content_to_send))+"\r\n\r\n"+content_to_send)