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Errno 107 Transport endpoint is not connected with Socket

I'm trying to make a connection tester with python and made this function:
import socket as skt
import sys
def main():
try:
s = skt.socket(skt.AF_INET, skt.SOCK_STREAM, 0)
except skt.error as e:
print('A conexão falhou! :(')
print(f'Erro {e}.')
sys.exit()
print("Socket criado com sucesso!")
HostTarget = input('Digite o Host ou IP a ser conectado: ')
DoorTarget = (input('Digite a porta a ser conetcada: '))
try:
s.connect:((HostTarget, int(DoorTarget)))
print(f'Cliente conectado com sucesso no Host: {HostTarget} através da porta: {DoorTarget}.')
s.shutdown(2)
except skt.error as e:
print(f'Não foi possível se conectar ao Host: {HostTarget} através da porta: {DoorTarget}.')
print(f'Erro: {e}')
sys.exit()
if __name__ == "__main__":
main()
But when I run the test, I get the following error:
Erro: [Errno 107] Transport endpoint is not connected
An exception has occurred, use %tb to see the full traceback.

TCP server does not return a message to the client

This is the client:
from socket import *
server_IP_address = '127.0.0.1'
server_Port = 60000
server_socket_address = (server_IP_address, server_Port)
socket_del_cliente = socket(AF_INET, SOCK_STREAM)
socket_del_cliente.connect(server_socket_address)
mensaje_tx = input ('Introduzca su mensaje en minúsculas: ')
socket_del_cliente.sendto(mensaje_tx.encode(), server_socket_address)
print('mensaje enviado')
mensaje_rx= conexionSocket.recv(2048)
print('Recibido del servidor: ', mensaje_rx.decode())
socket_del_cliente.close()
And this is the server:
from socket import *
server_Port = 60000
socket_del_servidor = socket(AF_INET, SOCK_STREAM)
socket_del_servidor.bind(('', server_Port))
socket_del_servidor.listen(5)
conexionSocket, clientAddress1= socket_del_servidor.accept()
print('Servidor preparado para recibir')
print(clientAddress1)
mensaje_tx, clientAddress2 = conexionSocket.recvfrom(2048) #responder a la misma direccion desde la que se ha enviado
print(clientAddress2)
print('Buen mensaje', mensaje_tx.decode())
mensaje_rx = input('Introduce una respuesta: ')
socket_del_servidor.sendto(mensaje_rx.encode(), clientAddress1)
print('Mensaje enviado', mensaje_rx)
socket_del_server.close()
if i run both the server and the client, the client is able to send a message to the server but the server is not able to send a message back

This is a simple example that you can use
server :
from socket import *
server = socket(AF_INET, SOCK_STREAM)
server.bind(("",6000))
server.listen(5)
while True:
connection,address = server.accept()
msg=connection.recv(1024)
print(msg.decode())
connection.send("Thank you".encode())
connection.close()
client :
from socket import *
so = socket(AF_INET, SOCK_STREAM)
so.connect(("127.0.0.1",6000))
so.send("hello server".encode())
print(so.recv(1024).decode())
so.close()
output :
Your mistake was that the server was not constantly waiting for the message

python multithreaded server unable to receive data from client

In the frame of our course, our teacher asked us to write a client-server program, where the server split two matrices that it wants to multiply then send them to the client and the client should calculate their part of the result and send it back to the server.
I succeed to divide the matrix and send it to clients but my problem is that my client cannot send back the results to the server. When I try to receive any message at the server-side, my client no longer receives the matrix to compute.
Here is my server code
!/usr/bin/env python
# -*- coding: utf-8 -*-
from socket import socket, AF_INET, SOCK_STREAM, timeout
from threading import Thread
import numpy as np
import pickle
buf = 4096
class ErrorLevels:
OK = "OK"
ERROR = "ERREUR"
class Server(Thread):
def __init__(self):
Thread.__init__(self)
self.socket = socket(AF_INET, SOCK_STREAM)
self.socket.bind(("localhost", 2020))
self.socket.settimeout(0.5)
self.running = False
self.client_pool = []
def client_handling_stopped(self, client, error_level, error_msg):
print("Le gerant de {} s'est arrete avec le niveau d'erreur {} ({})".format(client.address[0],error_level,error_msg))
self.clean_up()
# self.log_connection_amount()
def log_connection_amount(self):
print("Il y a maintenant {} client(s) connecte(s)".format(len(self.client_pool)))
def stop(self):
print("Arrêt du serveur")
for client in self.client_pool:
client.close_connection()
self.running = False
def clean_up(self):
"""
Enleve tous les gérants de clients innactifs de la liste des gerants de clients
"""
self.client_pool = [client for client in self.client_pool if client.alive]
#le serveur genere le calcul a envoyer aux clients
#generation de matrices
def matrice_aleatoire(self,intervalle, ligne, colonne):
matrice = np.random.randint(intervalle, size=(ligne, colonne))
return matrice
def run(self):
A = self.matrice_aleatoire(10,100,100)
B = self.matrice_aleatoire(10,100,100)
#code fonctionnnant pour 10 clients
#division de A en 10 sous matrices de 10 lignes et envoie aux clients
C = np.vsplit(A, 10)
#dictionnaire a envoyer a chaque client
data = []
for i in range(10):
dic = {'num':i,'partA':C[i],'partB':B}
data.append(dic)
print("Démarrage du serveur\nAttente des connexions clients...")
self.running = True
self.socket.listen(5)
i=-1
while self.running:
try:
client, address = self.socket.accept()
i=i+1
except timeout:
continue # on retourne au début de la boucle jusqu'à avoir un client
print("Connexion depuis {}".format(address))
#envoie et reception du calcul aux clients connnectes
#actuellement 10 clients
client_handling = ClientHandling(client, address,data[i], self.client_handling_stopped)
self.client_pool.append(client_handling)
client_handling.start()
# self.log_connection_amount()
#classe d'ojbets thread pour gerer les connections clients
class ClientHandling(Thread):
def __init__(self, client, address,data, exit_callback):
Thread.__init__(self)
self.client = client
self.address = address
self.data = data
self.exit_callback = exit_callback # une fonction qui devra être appelée lorsque cet objet sera devenu inactif
self.alive = True
def _stop(self, error_level, error_msg):
self.alive = False
self.close_connection()
self.exit_callback(self, error_level, error_msg)
def close_connection(self):
self.alive = False
self.client.close()
print("Fin de la communication avec {}".format(self.address))
def run(self):
try:
#envoie du calcul
print("debut envoie du calcul")
data_string = pickle.dumps(self.data)
self.client.sendall(data_string)
print("fin envoie")
#reception resultat
'''
here is the problem when i try to receive the result
pick_ = b''
while 1:
dat = self.client.recv(buf)
pick_ += dat
print("reception resultat")
if not dat:break
res = pickle.loads(dat)
print("fin reception")
# print(res)'''
#quelques exceptions possibles
except ZeroDivisionError:
self._stop(ErrorLevels.ERROR, "Une division par zero tente")
except ConnectionAbortedError:
if self.alive: # innatendu
self._stop(ErrorLevels.ERROR, "La connexion abandonnee")
else: # on est dans le cas où le gérant est volontairement arrêté
return # on arrête donc tout, plus besoin de faire quoi que ce soit
self._stop(ErrorLevels.OK, "Le client a ferme la connection")
try:
#lancement du thread serveur
server = Server()
server.start()
while True: continue
except KeyboardInterrupt:
server.stop()
server.join()
here is my client.py
import socket
from threading import Thread
#import numpy as np
import pickle
hote = "localhost"
port = 2020
buf = 4096
connexion_avec_serveur = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
connexion_avec_serveur.connect((hote, port))
print("Connexion établie avec le serveur sur le port {}".format(port))
#thread pour le calcul du client
class Calcul(Thread):
def __init__(self):
Thread.__init__(self)
#fonction qui extrait les donnees et multiplie
def multmat(self,data):
num = data['num']
A = data['partA']
B = data['partB']
C = A # B
resul = {'num':num,'partC':C}
return resul
def run(self):
#reception calcul
pick_str = b''
while 1:
data = connexion_avec_serveur.recv(buf)
pick_str += data
if not data:break
#connexion_avec_serveur.close()
dic = pickle.loads(pick_str)
#print(dic)
#calcul du produit
res = self.multmat(dic)
print(res)
#envoie du resultat du calcul
data_string = pickle.dumps(res)
connexion_avec_serveur.sendall(data_string)
cal = Calcul()
cal.start()
cal.join()
connexion_avec_serveur.close()

The main problem is that the client does not know when the complete message from the server has been received. The receiving code expects the server to close the connection before it can process the incoming data. However, the server can not close the connection because it is waiting for the client to send a response over the same connection.
The client is blocked at data = connexion_avec_serveur.recv(buf) until the server closes the connection, or some other network event occurs that severs that connection. Meanwhile the server is also blocked at dat = self.client.recv(buf) awaiting a response from the client - there is a deadlock.
The solution is to arrange for the client to know when it has received the complete message from the server, which means adding some protocol. One way is for the sever to append a sentinel value to signal the end of the message, and for the client to watch for that sentinel. Another way is for the server to prepend to the message the length of the payload, in this case the length of the pickled data, which I show here.
For the client change the run() function:
import struct
def run(self):
# First 4 bytes are the length of the payload
data = connexion_avec_serveur.recv(4)
msglen = struct.unpack('!L', data)[0]
print(f'Length of payload {msglen = }')
payload = []
while msglen > 0:
print(f'{msglen = } calling recv...')
data = connexion_avec_serveur.recv(buf)
print(f'received {len(data)} bytes')
payload.append(data)
msglen -= len(data)
print(f'total bytes read {sum(len(s) for s in payload)}')
dic = pickle.loads(b''.join(payload))
#print(dic)
#calcul du produit
res = self.multmat(dic)
print(res)
#envoie du resultat du calcul
data_string = pickle.dumps(res)
connexion_avec_serveur.sendall(data_string)
And for the server:
import struct
def run(self):
try:
#envoie du calcul
print("debut envoie du calcul")
data = pickle.dumps(self.data)
# prepend message with length of the pickled data
msg = struct.pack(f'!L{len(data)}s', len(data), data)
print(f'sending {len(msg)} bytes to client')
self.client.sendall(msg)
print("fin envoie")
#reception resultat
pick_ = b''
while True:
print('calling recv()')
dat = self.client.recv(buf)
print(f'recv() returned {len(dat)} bytes')
pick_ += dat
print("reception resultat")
if not dat:
break
res = pickle.loads(pick_)
print(f'{res = }')
print("fin reception")
#quelques exceptions possibles
except ZeroDivisionError:
self._stop(ErrorLevels.ERROR, "Une division par zero tente")
except ConnectionAbortedError:
if self.alive: # innatendu
self._stop(ErrorLevels.ERROR, "La connexion abandonnee")
else: # on est dans le cas où le gérant est volontairement arrêté
return # on arrête donc tout, plus besoin de faire quoi que ce soit
self._stop(ErrorLevels.OK, "Le client a ferme la connection")

Socket Problem in Python when send data to server

I have a problem when I send data from client to server in python INET Stream socket.
I send a dictionary using library json of python , and , in the server side, I create a Ticket object and save in my MySQL DB.
At this point, the program don't have any problems, but, when i try save other ticket in the same ejecution of client, the server not recieve the data and , the ticket don't save in the DB. Any solutions?
In server.py
def thread_fuction(port,sock):
while True:
msg = clientsocket.recv(1024)
print(f"Recibido del puerto {port} atendido por PID {os.getpid()}: {msg.decode()}")
logger(sock,msg)
if (msg.decode() == 'INSERTAR'):
dict_data=sock.recv(1024).decode()
final_data=json.loads(dict_data)
final_data=dict(final_data)
for key,value in final_data.items():
if key == "autor":
autor=value
elif key == "titulo":
titulo=value
elif key == "descripcion":
descripcion=value
elif key == "estado":
estado=value
print(final_data)
ticket=Ticket(autor=autor,titulo=titulo,descripcion=descripcion,estado=estado,fecha=datetime.now())
session.add(ticket)
session.commit()
break
# creamos el objeto socket
try:
serversocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
except socket.error:
print('Fallo al crear el socket!')
sys.exit()
#Establecemos parametros
host = "localhost"
port = int(8070)
# Blindeamos el puerto y el host
serversocket.bind((host, port))
# Establecemos 5 peticiones de escucha como maximo.
serversocket.listen(5)
if __name__ == "__main__":
while True:
# establish a connection
clientsocket, addr = serversocket.accept()
print('Conexion establecida: SERVER ON')
conection=Thread(target=thread_fuction,args=(port,clientsocket))
conection.start()
In client.py
try:
client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
print("Socket Creado!")
except socket.error:
print ('Fallo al crear el socket!')
sys.exit()
host = "localhost"
port = int(8070)
client_socket.connect((host, port))
print ('Socket conectado al host', host, 'en el puerto', port)
while True:
print("""\n
\t\t\t *** Menu ***
- INSERTAR TICKET (INSERTAR)
- SALIR (SALIR)
""")
opcion = input('Opcion: ').upper()
client_socket.sendto(opcion.encode(), (host, port))
if (opcion == 'INSERTAR'):
autor = input("\nIngrese autor del Ticket: ")
titulo = input("\nIngrese titulo del ticket: ")
descripcion = input("\nIngrese descripcion del ticket: ")
estado = input("\nIngrese estado del ticket (pendiente, en procesamiento o resuelto): ")
while validar_estado(estado):
estado=input("Estado debe ser uno de los pedidos, intentelo nuevamente): ")
data={"autor":autor,"titulo":titulo,"descripcion":descripcion,"estado":estado}
json_data=json.dumps(data) #Convertimos el diccionario a JSON
client_socket.sendto(json_data.encode(),(host,port))

Read and Write Socket-SerialPort use expensive CPU

def threadSocket(Socket, port):
'''
Thread encargado de sotener comunicacion entre Socket cliente y
el puerto serial asignado
Mientras se mantenga activo el thread de recepcion se intentara leer del
puerto serial y enviarlo al socket cliente
Se asume que socket y port son objetos vaidos validos
'''
#Intenta abrir el puerto serial
try:
COM = serial.Serial(port-1)
except:
#Si esta en uso no se encuentra disponible, muestra error
print 'Error: Puerto COM'+str(port)+' no disponible'
else:
#Al conectarse se crea el thread de recepcion
print 'Conectado a puerto COM'+str(port)
rxThread = threading.Thread(target=rxThreadDef,args=(Socket,COM))
rxThread.start()
dato = ''
#Mientras el thread este activo
while rxThread.isAlive():
try:
#Lee del puerto serial y envia a Socket cliente
dato += COM.read()
if parserCOMToSocket(dato):
Socket.send(dato)
dato=''
except:
break
print "Puerto cerrado!"
#Cierra puerto Serial
COM.close()
#Cierra Socket
Socket.close()
#print "Hilo terminado"
def rxThreadDef(Socket,COM):
'''
Thread (Hilo) encargado de recibir la informacion del Cliente
y enviarla por medio del puerto serial
Si se genera algun error se rompe el ciclo y termina el thread
'''
dato = ''
while 1:
try:
d = Socket.recv(1024)
except:
break
if d:
dato += d
if parserSocketToCOM(dato):
COM.write(dato)
print dato
dato = ''
else:
break
def parserSocketToCOM(dato):
return True
def parserCOMToSocket(dato):
return True
Hi, I try to implement a bridge between a serial port and a AIR application using sockets in Python 2.7
When the rxThread die, the socketThread will be able to close the socket and the serial Port because the client socket is die. But the script need to wait for a read from the serial port before close all.
If I try with a timeout=0, the CPU usage grow to 100%. If I try with a timeout=None but use COM.isWaiting(), I will get the same problem (100% of CPU)
How can I know if a socket is closed in other way?

If you need to read from two sources, you can do it happily with select(). You won't need threads in that case. select blocks until one or more of the resources is available, and then returns the set of resources available, so you can react on each. Note that select works with file descriptors and you may need to put it in nonblocking mode.