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socket python library. client crashes

I start the server, then the client, the server gets the data and the client does not get a response, crashes
server
import pygame, socket, time
pygame.init()
main_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
main_socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
main_socket.bind(("localhost", 10000))
main_socket.setblocking(0)
main_socket.listen(5)
players_sockets = []
while True:
try:
new_socket, addr = main_socket.accept()
print("Connect", addr)
new_socket.setblocking(0)
players_sockets.append(new_socket)
except:
pass
for i in players_sockets:
try:
data = i.recv(1024)
data = data.decode()
except:
pass
for i in players_sockets:
try:
i.send("server data").encode()
except:
players_sockets.remove(i)
print("Disconnect")
i.close()
time.sleep(1)
client
import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
sock.connect(("localhost", 10000))
while True:
sock.send("Command".encode())
data = sock.recv(1024)
data = data.decode()
print(data)
error:
" data = sock.recv(1024)
ConnectionAbortedError: [WinError 10053] The program on your host computer has broken an established connection."

Server is receiving data even after connection closed

I'm sending a file to the client. It works great. But when i'm sending a big file and close the client's terminal suddenly(which is sending data at that time), server doesn't stop writing the data.(After I close the connection(terminal of the client), more time I wait, more server’s file get bigger.)I want to make system protected against error because i may encounter this problem. The still-working part (in server)is:
while True:
data = conn.recv(4096)
if not data:
break
f.write(data)
server.py:
import time
import socket
port = 3030
s = socket.socket()
host = '' #public ip(aws)
s.bind((host, port))
s.listen(5)
print ('Server listening....')
def resultf(supp):
return 'calculated'
while True:
try:
conn, addr = s.accept()
print ('Got connection from', addr)
supp = conn.recv(1024)
print('Server received', supp.decode('utf-8'))
conn.send(supp)
with open('tobecalculated.txt', 'wb') as f:
while True:
data = conn.recv(4096)
if not data:
break
f.write(data)
conn.close()
result=resultf(int(supp))
conn, addr = s.accept()
conn.send(str(result).encode())
print('Done sending')
except Exception as E:
print(E)
try:
conn.send(b"Exception occurred. Try again")
except Exception as SendError:
pass
finally:
conn.close()
client.py:
import socket
import time
try:
s = socket.socket()
host='' # Server public ip
port =3030
s.connect((host, port))
supp=1
s.send(str(supp).encode("utf-8"))
print(s.recv(1024).decode())
with open('tobecalculated.txt', 'rb') as f:
l = f.read()
while (l):
s.send(l)
l = f.read()
s.shutdown(socket.SHUT_WR)
s.close()
while True:
try:
s = socket.socket()
s.connect((host, port))
print('Receiving')
result = s.recv(1024)
print('Received:')
break
except Exception as calc:
print('Calculating... Please wait',calc)
with open('file.txt', 'wb') as f:
f.write(result)
print(result.decode())
s.close()
print('Connection closed')
except Exception as E:
print(E)
Lastly, I tried(after closing connection/terminal) this to see if data is same but it says 'not same'
import time
import socket
port = 3030
s = socket.socket()
host = '' #public ip(aws)
s.bind((host, port))
s.listen(5)
print ('Server listening....')
def resultf(supp):
return 'calculated'
while True:
try:
conn, addr = s.accept()
print ('Got connection from', addr)
supp = conn.recv(1024)
print('Server received', supp.decode('utf-8'))
conn.send(supp)
global a
a=0
index=0
with open('tobecalculated.txt', 'wb') as f:
while True:
data = conn.recv(4096)
if data==a:
print('same',index)
else:
print('not same',index))
index+=1
a=data
if not data:
break
f.write(data)
conn.close()
result=resultf(int(supp))
conn, addr = s.accept()
conn.send(str(result).encode())
print('Done sending')
except Exception as E:
print(E)
try:
conn.send(b"Exception occurred. Try again")
except Exception as SendError:
pass
finally:
conn.close()

How can I receive multiple messages from one connection?

I have a server and I need it to receive multiple connections and messages.
The server receives new connections without problems but it doesn't get multiple messages from one connection.
import socket
import select
HEADER_LENGTH = 1024
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
try:
server_socket.bind((HOST, PORT))
except socket.error as e:
print(str(e))
print("Server is connected")
server_socket.listen(5)
sockets_list = [server_socket]
clients = {}
print("Server is listening")
def receive_message(conn):
try:
data = conn.recv(HEADER_LENGTH)
if not len(data):
return False
strdata = data.decode('utf-8')
print(strdata)
return strdata
except Exception as e:
print(e)
return False
def handle_client():
conn, addr = server_socket.accept()
print(f"Accepted new connection from {addr[0]}:{addr[1]}")
sockets_list.append(conn)
while True:
read_sockets, _, exception_sockets = select.select(sockets_list, [], [], 0)
for i in read_sockets:
if i == server_socket:
handle_client()
else:
print("received message")
message = receive_message(i)
if message is False:
sockets_list.remove(i)
try:
del clients[i]
except KeyError:
pass
continue
if message is not None:
clients[i] = message
if message is not None:
for client_socket in clients:
if client_socket != i:
client_socket.send(str.encode(message))
print("sent to all players")
What happens it that after receiving the first message, the server stops receiving messages from that connection.
And of course there is a lot more code but I showed you the relevant code.
I'll be very happy if someone helps me with that, I've surfed the web so much but haven't seen a solution for my problem.
updates:
I've tried to put socket.close() on my client side(written in Java) and then server gets maximum 2 messages and the problems with it are:
1. The server gets maximum 2 messages.
2. the connection changes(I need that the connection will stay static if possible)

try this code block
#-*- coding:utf-8 -*-
import socket
import sys
#get machine ip address
server_ip = socket.gethostbyname(socket.gethostname())
#create socket object
s = socket.socket()
#define port number
port = 6666
#bind ip and port to server
s.bind((server_ip,port))
#now waiting for clinet to connect
s.listen(5)
print("Enter this ip to connect your clinet")
print(server_ip)
clients = []
flag = True
recv_data = ""
if not clients:
c, addr = s.accept()
print("this is c ",c," this is Addr ",addr)
clients.append(c)
recv_data = c.recv(1024)
print(recv_data.decode("utf-8"))
if flag == True:
while recv_data.decode("utf-8") != "EX":
recv_data = c.recv(1024)
recv_data.decode("utf-8")
if recv_data.decode("utf-8") == "EX":
s.close()
print("check false")
break
s.close()

How to send data to client with conn.send()

Im trying to create a simple chat server. I've been able to send information to the server through the client using 'client.send()' but I cannot seem to do the same server->client
I have tried using methods such as conn.send() and conn.sendall(), but (I guess since the code is in a try) they seem to get skipped after the initial conn.send(str.encode("Connected"))
Server code
import socket
from _thread import *
import sys
server = "192.168.0.4"
port = 5555
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
s.bind((server, port))
except socket.error as e:
str(e)
s.listen(2)
print("Waiting for a connection, Server Started")
def threaded_client(conn):
conn.send(str.encode("Connected"))
reply = ""
while True:
conn.send(str.encode(str(reply)))
try:
data = conn.recv(2048*1)
reply = data.decode("utf-8")
if not data:
print("Disconnected")
break
else:
print("Received: ", reply)
print("Sending : ", reply)
conn.sendall(str.encode(reply)) #Where I want to send information to the client
except:
break
print("Lost connection")
conn.close()
while True:
conn, addr = s.accept()
print("Connected to:", addr)
start_new_thread(threaded_client, (conn,))
client code
import socket
class Network:
def __init__(self):
self.client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.server = "192.168.0.4"
self.port = 5555
self.addr = (self.server, self.port)
self.id = self.connect()
print(self.id)
def connect(self):
try:
self.client.connect(self.addr)
return self.client.recv(2048).decode()
except:
pass
def send(self, data):
try:
self.client.send(str.encode(data))
return self.client.recv(2048).decode()
except socket.error as e:
print(e)
from network import Network
n = Network()
while True:
n.send("sending stuff") #this works/sends properly

You forgot to use print() to display data from server
while True:
print( n.send("sending stuff") )
BTW: in server you send the same data two times - with conn.send() and conn.sendall()

Why I do not caught socket timeout?

I do not understand, why in this code below I do not have the timeout (even if I set it with settimeout, I cant see the exception caught):
import socket
HOST = 'x.x.x.x'
open_ports = []
closed_ports = []
def scan(PORT):
sock_tcp = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
#sock_tcp.settimeout(0.5)
SERVER_ADDR = (HOST, PORT)
try:
portStatusTCP = sock_tcp.connect_ex(SERVER_ADDR)
if portStatusTCP==0:
open_ports.append(PORT)
print(str(PORT)+' is OPEN')
else:
closed_ports.append(PORT)
print(str(PORT)+' is CLOSED')
except socket.error as socketerror:
print("ERROR"+socketerror)
sock_tcp.close()
for PORT in range(15,25):
print('scanning port: '+str(PORT))
scan(PORT)
print(open_ports)
print(closed_ports)