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UDP Tracker only gives me my ip as answer to announce request

I've recently been trying to create a torrent client in python, and have just got the UDP announce protocol to work.
The tracker accepts my connect request just fine but only returns my IP and port as the peer list when I announce to it...
I've tried to look at the same torrents in other torrent clients and they have multiple working peers while my request only shows me my computer (I've tried this on many torrents, all return just my IP and port)
Here's the code for the sending function itself:
async def announce_udp(self, try_num = 1):
self.sock.settimeout(15)
answer = {}
inner_while = False
while try_num < 4:
while try_num < 4:
try:
print("trying to send")
sended = self.send(1, self.announce_payload())
print("sending the following packet: {0}".format(sended))
print(self.url)
inner_while = True
break
except Exception:
print("problem in sending")
try_num += 1
if not inner_while:
break
try:
answer = self.interpret(15)
break
except Exception:
print("problem in receiving")
try_num += 1
print("announce answer is: {0}".format(answer))
return answer
here's the code for the make payload function:
def announce_payload(self, downloaded = 0, left = 0, uploaded = 0, event = 0, key = get_transaction_id()):
payload = [self.torrent.get_torrent_info_hash_decoded(), get_peer_id().encode(), downloaded,
self.torrent.get_torrent_size(), uploaded, event, 0, key, -1, 6988]
p_tosend = None
try:
p_tosend = struct.pack('!20s20sqqqiIIiH', *payload)
except Exception as e:
print("there was an error: {0}".format(e))
return p_tosend
here's the code for the interpret + process function:
def interpret(self, timeout=10):
self.sock.settimeout(timeout)
print("got to interpret")
try:
response = self.sock.recv(10240)
print("answer recieved")
except socket.timeout:
print("no answer, try again")
raise TrackerResponseException("no answer", 0)
headers = response[:8]
payload = response[8:]
action, trans_id = struct.unpack('!ll', headers)
try:
trans = self.transactions[trans_id]
except KeyError:
raise TrackerResponseException("InvalidTransaction: id not found", trans_id)
try:
trans['response'] = self.process(action, payload, trans)
except Exception as e:
trans['response'] = None
print("error occured: {0}".format(e))
trans['completed'] = True
del self.transactions[trans_id]
#print(trans)
return trans
def process_announce(self, payload, trans):
response = {}
info = payload[:struct.calcsize("!lll")]
interval, leechers, seeders = struct.unpack("!lll", info)
print(interval, leechers, seeders, "noamsssssss")
peer_data = payload[struct.calcsize("!lll"):]
peer_size = struct.calcsize("!lH")
num_of_peers = int(len(peer_data) / peer_size)
print("the number of peers is: {0} and the peer data is: {1}".format(num_of_peers, peer_data))
print()
peers = []
for peer_offset in range(num_of_peers):
off = peer_size * peer_offset
peer = peer_data[off:off + peer_size]
addr, port = struct.unpack("!lH", peer)
peers.append({
'addr': socket.inet_ntoa(struct.pack('!L', addr)),
'port': port,
})
print(payload)
return dict(interval=interval, leechers=leechers, seeders=seeders, peers=peers)
I'm sorry if any of this is irrelevant, but I want to give you all of the code incase it tells you something.
(get_peer_id() returns a random peer id per the tracker protocol specification, and the get_transaction_id() returns random.randint(0, 1 << 32 - 1))
EDIT:
Alright, I've found the problem and now I'm feeling pretty dumb...
turns out even in the udp tracker whenever you send the info hash it has to be SHA1 encoded.
Hopefully this can help someone if they are stuck in the same problem :)

Server/Client app and JSONDecodeError: Unterminated string python

I have async socket server file and client file.
When i send something like that "download filename.ex" to the client, this client's code hande my request:
try:
content = read(sp_data[-1]).decode('utf-8')
print(content)
msg = json.dumps({'file': sp_data[-1], 'command': data, 'content': content,
'msg': f'[+] File {sp_data[-1]} has been successfully downloaded.'}).encode('utf-8')
except FileNotFoundError:
msg = json.dumps({'msg': f'[-] File {sp_data[-1]} not found', 'command': data}).encode('utf-8')
s.send(msg)
When client send some data to the socketserver, this server's code handle received message:
def recv_message(client_socket):
global messages
data = json.loads(client_socket.recv(4096).decode('utf-8').strip()) ##Important here i got this error json.decoder.JSONDecodeError: Unterminated string starting at: line 1 column 67 (char 66)
raddr = get_raddr(str(client_socket))
raddr = f'{raddr[0]}:{raddr[1]}'
message = f'From: {raddr}\nCommand: {data["command"]}\nOutput: \n\n{data["msg"]}'
try:
d = messages[raddr]
d.append(message)
messages[raddr] = d
except KeyError:
messages[raddr] = [message]
except AttributeError:
print(message, messages)
if 'content' in data.keys(): ##Important
print(data['content'])
threading.Thread(target=create_file, args=(data['file'], data['content'],), daemon=False).start()
Error:
data = json.loads(client_socket.recv(4096).decode('utf-8').strip())
json.decoder.JSONDecodeError: Unterminated string starting at: line 1 column 67 (char 66)
But server's code above give me this error when it receive message from the first code(when i send something like that "download file.ex" to the client, client detect my command as its special command, execute the first code, send json file to the server. But if i send "dir" command to the client, it will detect my command like shell command, will run command through subprocess, will send result to the server back and i won't get any errors.)
Note: I also reduced socketserver's code. Therefore, something in my code can work worse. The main goal of this post - make download feature works. I also understand that my code is big. I left "##Important" comments in my files. U can watch only code that located by these comments.
Server:
import selectors
import socket
import threading
import json
import base64
import shlex
selector = selectors.DefaultSelector()
connections = {}
def accept_conn(server_socket):
sock, addr = server_socket.accept()
connections[len(connections) + 1] = [sock, f'{addr[0]}:{addr[-1]}']
selector.register(fileobj=sock, events=selectors.EVENT_READ, data=recv_message)
s = socket.socket()
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind(('localhost', 4444))
s.listen()
selector.register(fileobj=s, events=selectors.EVENT_READ, data=accept_conn)
messages = {}
##Important
def create_file(file, content): #content - base64 string
print(content)
with open(file, 'wb') as f:
f.write(base64.b64decode(content.encode('utf-8')))
def recv_message(client_socket):
global messages
data = json.loads(client_socket.recv(4096).decode('utf-8').strip()) ##Important here i got this error json.decoder.JSONDecodeError: Unterminated string starting at: line 1 column 67 (char 66)
raddr = get_raddr(str(client_socket))
raddr = f'{raddr[0]}:{raddr[1]}'
message = f'From: {raddr}\nCommand: {data["command"]}\nOutput: \n\n{data["msg"]}'
try:
d = messages[raddr]
d.append(message)
messages[raddr] = d
except KeyError:
messages[raddr] = [message]
except AttributeError:
print(message, messages)
if 'content' in data.keys(): ##Important
print(data['content'])
threading.Thread(target=create_file, args=(data['file'], data['content'],), daemon=False).start()
def get_raddr(string):
'''Get raddr parameter from client socket'''
raddr = string.replace('>', '')
return eval(raddr[raddr.find('raddr')::].replace('raddr=', ''))
def is_manage_string(sub, string):
tokens = shlex.split(string)
try:
if len(tokens) == 2 and tokens[0] == sub and str(int(tokens[-1])):
return True, int(tokens[-1])
except Exception as e:
print(e)
return False
manage_process = False
def manage():
global manage_process
while True:
manage_process = False
command = input('>>> ').strip()
if command == 'list':
try:
for i in range(1, len(connections) + 1):
print(f'{i}\t{connections[i][-1]}')
except KeyError:
pass
if len(connections) == 0:
print('[-] There are not any connections')
elif 'manage' in command:
index = is_manage_string('manage', command)
if index:
index = index[-1]
else:
print('[-] Invalid command\nUse manage "number_of_connection"\nEx: manage 1')
continue
if index >= 1 and index <= len(connections):
sock, addr = connections[index]
print(addr)
print(f'{addr} is used')
while True: ##Important here i launch loop which send data to socket
manage_process = True
command = input('>>> ').strip()
if command == 'messages':
try:
if messages[addr] == list():
print()
continue
except KeyError:
pass
try:
print('\n\n'.join(messages[addr]))
except KeyError:
print()
elif command == 'message':
try:
print(messages[addr][-1])
except:
print()
elif command == 'clear_messages':
try:
if messages[addr]:
messages[addr] = []
except KeyError:
print('[-] There are not any messages for cleaning up')
elif command == 'leave':
print(f'Leaving connection {addr}')
break
elif command: ##Important if command hasn't been detected as my special command(leave, messages), it will be executed like shell command
try:
sock.send(command.encode('utf-8'))
print(
'Your input has not been detected as special command and will execute like shell command or like client special command(ex: download; see client file)')
except ConnectionResetError:
print("Connection has been lost, therefore shell commands can't be used")
else:
continue
else:
print('[-] Invalid number of connection')
elif command:
print('[-] Invalid command\nType "help" to see avalible commands')
##Important
def event_loop():
while True:
data = selector.select()
for key, _ in data:
try:
key.data(key.fileobj)
except ConnectionResetError:
selector.unregister(key.fileobj)
##Important
threading.Thread(target=manage, daemon=True).start()
event_loop()
Client:
import socket
import subprocess
import shlex
import threading
import json
import base64
s = socket.socket()
s.connect(('localhost', 4444))
##Important
def read(file):
with open(file, 'rb') as f:
return base64.b64encode(f.read())
def runner(data):
sp_data = shlex.split(data)
try:
print(sp_data)
if len(sp_data) == 2 and sp_data[0] == 'download': ###Important here we create json object which will be send to socketserver
try:
content = read(sp_data[-1]).decode('utf-8')
print(content)
msg = json.dumps({'file': sp_data[-1], 'command': data, 'content': content,
'msg': f'[+] File {sp_data[-1]} has been successfully downloaded.'}).encode('utf-8')
except FileNotFoundError:
msg = json.dumps({'msg': f'[-] File {sp_data[-1]} not found', 'command': data}).encode('utf-8')
s.send(msg)
return ''
except Exception as e:
print(e)
command = subprocess.run(data, shell=True, encoding='cp866', text=True, capture_output=True)
command = command.stderr if command.stderr else command.stdout
command = json.dumps({'msg': command, 'command': data})
s.send(command.encode('utf-8'))
while True:##Important
data = s.recv(4096).decode('utf-8').strip()
threading.Thread(target=runner, args=(data,)).start()

import socket
import struct
class Socket(socket.socket):
def __init__(self):
self.sock = socket.socket()
super().__init__(socket.AF_INET, socket.SOCK_STREAM)
def send_msg(self, msg):
# Prefix each message with a 4-byte length (network byte order)
msg = struct.pack('>I', len(msg)) + msg
self.sock.sendall(msg)
def recv_msg(self):
# Read message length and unpack it into an integer
raw_msglen = self.recv_all(4)
if not raw_msglen:
return None
msglen = struct.unpack('>I', raw_msglen)[0]
# Read the message data
return self.recv_all(msglen)
def recv_all(self, n):
data = bytearray()
while len(data) < n:
packet = self.sock.recv(n - len(data))
if not packet:
return None
data.extend(packet)
return data
I reshaped ur code into Socket class.

Solution - usage these features:
def send_msg(sock, msg):
# Prefix each message with a 4-byte length (network byte order)
msg = struct.pack('>I', len(msg)) + msg
sock.sendall(msg)
def recv_msg(sock):
# Read message length and unpack it into an integer
raw_msglen = recvall(sock, 4)
if not raw_msglen:
return None
msglen = struct.unpack('>I', raw_msglen)[0]
# Read the message data
return recvall(sock, msglen)
def recvall(sock, n):
# Helper function to recv n bytes or return None if EOF is hit
data = bytearray()
while len(data) < n:
packet = sock.recv(n - len(data))
if not packet:
return None
data.extend(packet)
return data

Socket.close() doesn't close the Socket

I'm trying to develop a very simple client/server program, the server part is working properly but I've a problem with the client part but I can't understand why.
The client's work is very simple, just retrive the counter value from a external device, then I'm trying to send the retrieved data to the server part.
At the beginning the socket is working well, but some time when I should send the data I've got the server exception and after that the Client is not working.
I can't understand if the s.close() function is working properly.
UPDATE: the exception that I got is "errno 110 connection timed out"
Client:
import time, socket, struct, array, json
import Client_Axis
import sys
import serial
import os
import datetime
import re
import packet
import Config_mio
usbport = '/dev/ttyAMA0'
h = "/r/n"
if __name__=="__main__":
"""Main function that starts the server"""
curr_value = "0000000000"
prev_value = ""
line = '111111111111111'
error_counter = 0
people_in = 0
people_out = 0
txtDate = ""
no_updates_counter = 0
while True:
ser = None
try:
# print('1')
ser = serial.Serial('/dev/ttyAMA0', 9600, timeout=1)
# ser.open()
# print('2')
for line in ser.read():
line = ser.readline()
print(line[6:10])
curr_value = line
except:
print('Serial error')
# print('3')
pass
finally:
if ser:
ser.close()
try:
error_counter += 1
# print('1')
response = Client_Axis.Read_Axis_Camera_Occupancy()
content = response.split(",")
people_in_refresh = int(re.search(r'\d+', content[3]).group())
people_out_refresh = int(re.search(r'\d+', content[4]).group())
# print('2')
error_flag = 0
if people_in != people_in_refresh or people_out != people_out_refresh:
people_in = people_in_refresh
people_out = people_out_refresh
try:
# Creates TCP socket in the specified IP address and port
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
# Connect client to the server
s.connect((Config_mio.IP_Server_Add, Config_mio.ws_port))
# Create message and send it to server
timestamp = str(time.time())
# msg = packet("c", timestamp, Config_mio.RbPi_Id, content[3], content[4], None)
msg = "c"+","+str(timestamp)+","+str(Config_mio.RbPi_Id)+","+str(people_in)+","+str(people_out)+","+"None"
# json_message = json.dumps(msg)
# s.send(json_message)
s.send(msg)
print "messaggio INVIATO"
# Close connection when data is sent
#s.close()
except:
print('Server connection error 1')
pass
finally:
s.close()
#AXIS_occup_old = AXIS_occup
#AXIS_occup = response.read()
#my_dict = json.loads(AXIS_occup)
# print(AXIS_occup)
# print(my_dict)
#del my_dict["timestamp"]
#AXIS_occup = my_dict
#error_counter = 0
# print('3')
except:
error_msg = "Error retrieving occupancy from: " + Config_mio.IP_AXIS_Add
error_flag = 1
if (error_flag == 1):
no_updates_counter = 0
print "Error detected: %s \r\n" % error_msg
print error_counter
if (error_counter > 200):
os.system("sudo reboot")
elif (line[6:10] != '1111' and prev_value != curr_value):
try:
# Creates TCP socket in the specified IP address and port
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
# Connect client to the server
s.connect((Config_mio.IP_Server_Add, Config_mio.ws_port))
# Create message and send it to server
timestamp = str(time.time())
msg = "r"+","+str(timestamp)+","+str(Config_mio.RbPi_Id)+","+"None"+","+"None"+","+str(line[6:10])
#msg = {"Id": raspberry_id,
# "Ranging": line[6:10],
# "timestamp": timestamp}
#json_message = json.dumps(msg)
#s.send(json_message)
s.send(msg)
print "Message : %s" % msg
# Close connection when data is sent
s.close()
except:
print('Server connection error 2')
pass
else:
no_updates_counter += 1
# Send message despite there are no changes in value
# This is a heartbeat message of 10 min
if (no_updates_counter > 200):
no_updates_counter = 0
AXIS_occup = ""
prev_value = curr_value
# Reboot device every day - routine
# We have 4 cases incase we miss few seconds
txtDate = str(datetime.datetime.fromtimestamp(time.time()))
if (txtDate[11:19] == "00:00:00"):
os.system("sudo reboot")
if (txtDate[11:19] == "00:00:01"):
os.system("sudo reboot")
if (txtDate[11:19] == "00:00:02"):
os.system("sudo reboot")
if (txtDate[11:19] == "00:00:03"):
os.system("sudo reboot")
# Kill time - 1 sec: Remove it for high speed localisation
time.sleep(1)
Server:
import socket
import json
import time
import Config_mio
import packet
import sqlite3 as lite
if __name__ == "__main__":
"""Main function that starts the server"""
# Creates TCP socket in the specified IP address and port
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((Config_mio.IP_Server_Add, Config_mio.ws_port))
# Starts server, up to 10 clients are queued
s.listen(Config_mio.Max_Num_Clients)
while True:
conn, addr = s.accept()
#print "sono dopo ascolto"
msg = conn.recv(1024)
print "Data value:",msg
msg = msg.split(",")
if msg[0] == "c":
print "counter msg"
elif msg[0] == "r":
print "range msg",msg[1],msg[2],msg[5]
conn.close()

Python Multi-threaded socket listener error with threads not releasing

I have 500+ units in the world that connects to my server and dump their data. Up to now i have been using a PHP script to act as a socket listener, but I need to go multi-threaded as the load is increasing and PHP can not keep up. I am quite new to Python and decided to use it for my new platform, over the past few days i have struggled and tried many examples to no avail. Through my search i came across some questions trying to answer this problem, but none did. I will attach my code.
The problem : as the units connect to the server and the server accepts it, the server creates a new thread to handle the connection, the problem comes when the unit drops the connection the thread stays open and active and the total thread count grows, and this is linked to the system limit : "number of open files", i can increase this limit but this only make it a time bomb , it does not solve this.
Please help.
#! /usr/bin/python
import multiprocessing
import socket
import sys
import pprint
import datetime
import MySQLdb
import time
import datetime
import re
import select
import resource
import threading
max_connections = 1024
max_connections_set = max_connections
resource.setrlimit(resource.RLIMIT_NOFILE, (max_connections_set, max_connections_set))
#the incomming port
the_global_port = xxxx #(any port)
#display id
the_global_id = "UNIT TYPE"
class ConnectionObject(object):
the_id = None
the_socket = None
the_socket_address = None
the_socket_address_ip = None
the_socket_address_port = None
the_server = None
the_process = None
the_process_id = None
the_process_name = None
the_imei = None
identifier = ""
# The class "constructor" - It's actually an initializer
def __init__(self, in_process_nr, in_process , in_socket , in_socket_address, in_server):
self.the_id = in_process_nr
self.the_process = in_process
self.the_process_id = self.the_process.exitcode
self.the_process_name = self.the_process.name
self.the_socket = in_socket
self.the_socket_address = in_socket_address
self.the_socket_address_ip = self.the_socket_address[0]
self.the_socket_address_port = self.the_socket_address[1]
self.the_server = in_server
self.identifier = str(self.the_id) + " " + str(self.the_process_name) + " " + str(self.the_socket_address_ip) + " " + str(self.the_socket_address_port) + " "
#end def init
#end def class
def processData(the_connection_object , the_data):
def mysql_open_connection_inside():
try:
the_conn = MySQLdb.connect(host= "127.0.0.1",
user="user",
passwd="password",
db="mydb")
except MySQLdb.Error, e:
print "Error %d: %s" % (e.args[0], e.args[1])
time.sleep(30)
try:
the_conn = MySQLdb.connect(host= "127.0.0.1",
user="user",
passwd="password",
db="mydb")
except MySQLdb.Error, e:
print "Error %d: %s" % (e.args[0], e.args[1])
print "Unexpected error:", sys.exc_info()[0]
raise
sys.exit(0)
#end time 2
#end try except
return the_conn
#end def mysql_open_connection
conn = mysql_open_connection_inside()
x = conn.cursor()
add_rawdata = ("INSERT INTO RawData"
"(ID,RawData,Type) "
"VALUES (%s, %s, %s)")
data_raw = ('123456', 'ABCD','')
records_inserted = 0
the_connection_object.the_imei = ""
#global clients
imei = ""
try:
thedata = ""
thedata = " ".join("{:02x}".format(ord(c)) for c in the_data)
record_to_save = ' '.join(thedata)
seqtoreply = ""
seqtoreply = "OK"
#reply part
if (seqtoreply != ""): #reply to unit
try:
the_connection_object.the_socket.sendall(seqtoreply)
#echoout(the_connection_object.identifier+"We Replyed With : " + seqtoreply)
except:
echoout(the_connection_object.identifier+"Send Reply Error : " + str(sys.exc_info()[1]))
#end except
#end of if
the_id = "some generated id"
data_raw = (the_id, werk_data, 'UNIT')
try:
x.execute(add_rawdata, data_raw)
conn.commit()
echoout(the_connection_object.identifier+"Raw Data Saved.")
except:
conn.rollback()
echoout(the_connection_object.identifier+" Raw Data NOT Saved : " + str(sys.exc_info()[1]))
#end of data save insert
#echoout("=============================")
endme = 1
echoout("")
conn.close()
#end try
except:
conn.close()
echoout(the_connection_object.identifier+"Error : " + str(sys.exc_info()[1]))
#end try except
#end def handel function
def handle_p(processnr, server, connection, address):
this_connection = ConnectionObject(processnr,multiprocessing.current_process(), connection, address, server)
thisprocess = multiprocessing.current_process()
this_connection.the_id = ""
the_address = this_connection.the_socket_address_ip
the_port = this_connection.the_socket_address_port
try:
echoout("New connection from : "+str(the_address)+" on port "+str(the_port))
close_the_socket = False
while True:
#--------------------- recive part -------------------------------------------------
data = connection.recv(512)
thedata = ""
thedata = " ".join("{:02x}".format(ord(c)) for c in data)
if ((thedata == "") or (thedata == " ") or (data == False)):
echoout("Socket Closed Remotely : No Data")
close_the_socket = True
break
#end - if data blank
else :
processData(this_connection, data)
#end there is data
echoout("=============================")
#end if while true
#end try
except:
print "handling request, Error : " + str(sys.exc_info()[1])
close_the_socket = True
connection.close()
finally:
close_the_socket = True
echoout("Closing socket")
connection.close()
#end try finally
#end def handel function
def mysql_update(update_statement, update_values):
conn_update = MySQLdb.connect(host= "127.0.0.1",
user="user",
passwd="password",
db="mydb")
x_update = conn_update.cursor(MySQLdb.cursors.DictCursor)
rawdata_data = (update_statement)
data_rawdata = (update_values)
allupdateok = False
#end if there is more
try:
x_update.execute(rawdata_data, data_rawdata)
conn_update.commit()
allupdateok = True
conn_update.close()
except:
conn_update.rollback()
allupdateok = False
conn_update.close()
print "Unexpected error:", sys.exc_info()[0]
raise
#end of data save insert
if (allupdateok == False):
echoout("Update Raw Data Table Error")
#end if update
return allupdateok
#end def mysqlupdate
def echoout(thestring):
datestring = datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")
if (thestring != ""):
outstring = datestring + " " + thestring
print outstring
else :
outstring = thestring
print outstring
#end - def echoout
class Server(object):
threads = []
all_threads = []
high_proc = ""
def __init__(self, hostname, port):
self.hostname = hostname
self.port = port
def start(self):
echoout("Listening for conncetions")
self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
self.socket.bind((self.hostname, self.port))
self.socket.listen(10)
process_number = 1
inputs = [self.socket]
while True:
inready, outready, excready = select.select(inputs, [], [], 30);
for s in inready:
if s == self.socket:
conn, address = self.socket.accept()
high_processname = ""
echoout("Got a connection...")
process = threading.Thread(target=handle_p, args=(process_number,self, conn, address))
high_processname = process.name
self.high_proc = high_processname
process.daemon = True
process.start()
self.all_threads.append((process,conn))
ts = time.time()
st = datetime.datetime.fromtimestamp(ts).strftime('%Y-%m-%d %H:%M:%S')
self.threads.append((process_number,conn,st,0,process))
process_number = process_number + 1
print "ACTIVE Threads = " + str(threading.activeCount())
the_total_count = 0
dead_count = 0
alive_count = 0
for the_thread in self.all_threads :
if (the_thread[0].is_alive() == True):
alive_count = alive_count + 1
else :
dead_count = dead_count + 1
the_thread[1].close()
the_thread[0].join(0.3)
self.all_threads.pop(the_total_count)
#end if alive else
the_total_count = the_total_count + 1
#end for threads
print "LIVE Threads = " + str(alive_count)
print "DEAD Threads = " + str(dead_count)
print "TOTAL Threads = " + str(the_total_count)
print ""
#end if s = socke, new connection
#end for loop
#end while truw
self.socket.close()
#end def start
#main process part
if __name__ == "__main__":
start_ip = "0.0.0.0"
start_port = the_global_port
#start server
server = Server(start_ip, start_port)
try:
print "Listening on " , start_port
server.start()
except:
print "unexpected, Error : " + str(sys.exc_info()[1])
finally:
print "shutting down"
active_clients = 0
for process in multiprocessing.active_children():
try:
active_clients = active_clients + 1
process.terminate()
#process.join()
except:
print "Process not killed = " + str(sys.exc_info()[1])
#end try except
#close mysql connection
print "Active clients = " + str(active_clients)
#end try finally
server.socket.close()
server.threads = []
server = None
print "All done."
#end def main

First of all, it is silly to use threads when you can have 500+ connected clients, you should go asynchronous - look at gevent for example for
a very good library, or at least use select (see Python documentation).
Then, your code to close the socket in handle_p looks good, indeed when
the recv() call comes back with an empty string it means the remote
end is disconnected so you break the while, fine.
However, it looks like the remote closed the connection but it is not
detected on your side (recv() doesn't return). The best would be
then to have a kind of heartbeat to know when you can close the
connection.

How can I make multiclient server in python using multithreading?

This is the code that I have used.But I don't get actual result that I want.When I execute code ChatServer file works properly,but ChatClient gives only one line(Usage : python telnet.py hostname port).Please Help me.I am new in python.
The server code:
#!/usr/bin/env python
#!/usr/bin/env python
"""
A basic, multiclient 'chat server' using Python's select module
with interrupt handling.
Entering any line of input at the terminal will exit the server.
"""
import select
import socket
import sys
import signal
from communication import send, receive
BUFSIZ = 1024
class ChatServer(object):
""" Simple chat server using select """
def __init__(self, port=3490, backlog=5):
self.clients = 0
# Client map
self.clientmap = {}
# Output socket list
self.outputs = []
self.server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.server.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
self.server.bind(('',port))
print 'Listening to port',port,'...'
self.server.listen(backlog)
# Trap keyboard interrupts
signal.signal(signal.SIGINT, self.sighandler)
def sighandler(self, signum, frame):
# Close the server
print 'Shutting down server...'
# Close existing client sockets
for o in self.outputs:
o.close()
self.server.close()
def getname(self, client):
# Return the printable name of the
# client, given its socket...
info = self.clientmap[client]
host, name = info[0][0], info[1]
return '#'.join((name, host))
def serve(self):
inputs = [self.server,sys.stdin]
self.outputs = []
running = 1
while running:
try:
inputready,outputready,exceptready = select.select(inputs, self.outputs, [])
except select.error, e:
break
except socket.error, e:
break
for s in inputready:
if s == self.server:
# handle the server socket
client, address = self.server.accept()
print 'chatserver: got connection %d from %s' % (client.fileno(), address)
# Read the login name
cname = receive(client).split('NAME: ')[1]
# Compute client name and send back
self.clients += 1
send(client, 'CLIENT: ' + str(address[0]))
inputs.append(client)
self.clientmap[client] = (address, cname)
# Send joining information to other clients
msg = '\n(Connected: New client (%d) from %s)' % (self.clients, self.getname(client))
for o in self.outputs:
# o.send(msg)
send(o, msg)
self.outputs.append(client)
elif s == sys.stdin:
# handle standard input
junk = sys.stdin.readline()
running = 0
else:
# handle all other sockets
try:
# data = s.recv(BUFSIZ)
data = receive(s)
if data:
# Send as new client's message...
msg = '\n#[' + self.getname(s) + ']>> ' + data
# Send data to all except ourselves
for o in self.outputs:
if o != s:
# o.send(msg)
send(o, msg)
else:
print 'chatserver: %d hung up' % s.fileno()
self.clients -= 1
s.close()
inputs.remove(s)
self.outputs.remove(s)
# Send client leaving information to others
msg = '\n(Hung up: Client from %s)' % self.getname(s)
for o in self.outputs:
# o.send(msg)
send(o, msg)
except socket.error, e:
# Remove
inputs.remove(s)
self.outputs.remove(s)
self.server.close()
if __name__ == "__main__":
ChatServer().serve()
The chat client:
#! /usr/bin/env python
"""
Simple chat client for the chat server. Defines
a simple protocol to be used with chatserver.
"""
import socket
import sys
import select
from communication import send, receive
BUFSIZ = 1024
class ChatClient(object):
""" A simple command line chat client using select """
def __init__(self, name, host='127.0.0.1', port=3490):
self.name = name
# Quit flag
self.flag = False
self.port = int(port)
self.host = host
# Initial prompt
self.prompt='[' + '#'.join((name, socket.gethostname().split('.')[0])) + ']> '
# Connect to server at port
try:
self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.sock.connect((host, self.port))
print 'Connected to chat server#%d' % self.port
# Send my name...
send(self.sock,'NAME: ' + self.name)
data = receive(self.sock)
# Contains client address, set it
addr = data.split('CLIENT: ')[1]
self.prompt = '[' + '#'.join((self.name, addr)) + ']> '
except socket.error, e:
print 'Could not connect to chat server #%d' % self.port
sys.exit(1)
def cmdloop(self):
while not self.flag:
try:
sys.stdout.write(self.prompt)
sys.stdout.flush()
# Wait for input from stdin & socket
inputready, outputready,exceptrdy = select.select([0, self.sock], [],[])
for i in inputready:
if i == 0:
data = sys.stdin.readline().strip()
if data: send(self.sock, data)
elif i == self.sock:
data = receive(self.sock)
if not data:
print 'Shutting down.'
self.flag = True
break
else:
sys.stdout.write(data + '\n')
sys.stdout.flush()
except KeyboardInterrupt:
print 'Interrupted.'
self.sock.close()
break
if __name__ == "__main__":
import sys
if len(sys.argv)<3:
sys.exit('Usage: %s chatid host portno' % sys.argv[0])
client = ChatClient(sys.argv[1],sys.argv[2], int(sys.argv[3]))
client.cmdloop()
###############################################################################
# The communication module (communication.py)
###############################################################################
import cPickle
import socket
import struct
marshall = cPickle.dumps
unmarshall = cPickle.loads
def send(channel, *args):
buf = marshall(args)
value = socket.htonl(len(buf))
size = struct.pack("L",value)
channel.send(size)
channel.send(buf)
def receive(channel):
size = struct.calcsize("L")
size = channel.recv(size)
try:
size = socket.ntohl(struct.unpack("L", size)[0])
except struct.error, e:
return ''
buf = ""
while len(buf) < size:
buf = channel.recv(size - len(buf))
return unmarshall(buf)[0]