first of all i want to clarify. I don't have any deep knowledge on python, but im trying to learn while doing a project for college so lets start and thanks for your time.
I'm working with Python 3.4 on Windows 10 for the hosts and Ubuntu in an Odroid as a server.
The problem on my code is that i need to send a code like 0001 to a set of hosts of which i have their ips but when i try to close the socket it won't do it and i can't open a new one to send the code to the next host.
Client code :
[yes, it's a socket server code but when i try to connect multiple clients to one server, the code stopped on listening new connections and i couldn't "fix" it in another way]
while 1:
TCP_PORT = 5000
BUFFER_SIZE = 4 # Normally 1024, but we want fast response
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind(('', TCP_PORT))
s.listen(1)
s, addr = s.accept()
data = s.recv(BUFFER_SIZE)
if not data:
break
if data.decode('ascii') == '0001':
print (data.decode('ascii'))
s.shutdown(socket.SHUT_RDWR)
s.close()
Server side code:
import serial
import time
import mysql.connector
import shutil
import socket
import sys
import _thread
joined_seq = '0001'
Alerta = True
TotalClientes = True
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
seq = []
UltimaIPextraida = ''
port = 5000
while Alerta == True:
if TotalClientes == True:
cnx2 = mysql.connector.connect(connection parameters removed)
cursor2 = cnx2.cursor()
cursor2.execute("SELECT MAX(Entrada) FROM Host")
for (Entrada) in cursor2:
NoTupla = ''.join(str(v) for v in Entrada)
ValorMAX = int(NoTupla)
cursor2.close()
cnx2.close()
TotalClientes = False
if ValorMAX > 0:
print('Host Numero', ValorMAX)
cnx3 = mysql.connector.connect(connection parameters removed)
cursor3 = cnx3.cursor()
query = ("SELECT IP FROM Host WHERE entrada = '%s' " % (ValorMAX))
cursor3.execute(query)
for (IP) in cursor3:
IPextraida = ''.join(str(v) for v in IP)
cursor3.close()
cnx3.close()
#if ValorMAX == 1: #DESCOMENTAR
# Alerta = False #DESCOMENTAR
ValorMAX = ValorMAX -1
print('IP Extraida = ' + IPextraida)
print('Ultima IP Extraida = '+ UltimaIPextraida)
if UltimaIPextraida == IPextraida:
print('Ultima IP extraida es identica a la nueva ip extraida, pasando a la siguiente')
elif UltimaIPextraida != IPextraida:
try:
s.connect((IPextraida, port))
s.send(joined_seq.encode('ascii'))
s.shutdown(s.SHUT_RDWR)
s.close()
print('Mensaje enviado correctamente = ' + joined_seq)
except:
print('No se pudo conectar con host')
UltimaIPextraida = IPextraida
** some code was ommited because it has no relevance **
With the mysql query i get the total of ip entries on the table and then with that i get all ip one by one to make the socket connection.
I really hope someone can help me to solve this problem... i've been 2 days trying and i'm running out of time to finish the code and it isn't the main part of the project, i only need a functional code to show some capabilities of the arduino functions graphically.
thank you all for your time and sorry for the gramatical errors and the code in spanish :(
Solved with this:
def enviaMensaje(ipdelwn):
enviado=False
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
try:
s.connect((ipdelwn, port))
s.send(joined_seq.encode('ascii'))
s.close()
print('Mensaje enviado correctamente = ' + joined_seq)
enviado=True
except:
print('No se pudo conectar con host')
return enviado
Related
Is there something the client needs to do in order to flag that "This is the end?"
For example, I have the following server running:
import socket, sys
while True:
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind(('', 5500))
s.listen(1)
conn, addr = s.accept()
print('Connected by', addr)
data = b''
while True:
data_chunk = conn.recv(10)
data += data_chunk
if not data: break
# How do I get here so I can echo the message *at the end* ?
# conn.send(b'Done. What you sent was: %s' % data)
And I have the following client code:
import socket
client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client_socket.connect(('sandbox2.myip.com', 5500))
client_socket.send(b'select * from table')
# Now, what to do so that I can get the final message from he server?
When I do the connection though, this is what it shows:
sampleDB$ python listener.py
Connected by ('99.51.149.29', 63352)
I can confirm that the data data_chunks are being received, but then it just seems to hang at this part right here:
data_chunk = conn.recv(10)
Is there something I need to do in the client (or the server?) to flag that "This is the end of the transmission, so conn.recv() doesn't just hang indefinitely?
Here's a complete example of a socket based client/server protocol that implements the strategy described in my comment:
import socket
import threading
from struct import pack, unpack
HOST = 'localhost'
PORT = 7070
FORMAT = ('!Q', 8)
MSG = '''The Owl and the Pussy-cat went to sea
In a beautiful pea-green boat,
They took some honey, and plenty of money,
Wrapped up in a five-pound note.
The Owl looked up to the stars above,
And sang to a small guitar,
"O lovely Pussy! O Pussy, my love,
What a beautiful Pussy you are,
You are,
You are!
What a beautiful Pussy you are!"'''
def sendbuffer(s, b):
buffer = pack(FORMAT[0], len(b)) + b
offset = 0
while offset < len(buffer):
offset += s.send(buffer[offset:])
def recvbuffer(s):
p = s.recv(FORMAT[1], socket.MSG_WAITALL)
n = unpack(FORMAT[0], p)[0]
return None if n == 0 else s.recv(n, socket.MSG_WAITALL)
def server():
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.bind((HOST, PORT))
s.listen()
conn, _ = s.accept()
with conn:
while (data := recvbuffer(conn)):
sendbuffer(conn, data)
def client(msg):
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.connect((HOST, PORT))
sendbuffer(s, msg.encode())
data = recvbuffer(s)
print(data.decode())
sendbuffer(s, b'') # kill switch
def main():
threading.Thread(target=server).start()
client(MSG)
if __name__ == '__main__':
main()
Hello fellow programmer.
I followed this tutorial https://www.youtube.com/watch?v=QihjI84Z2tQ
Those server and client has successfully connected
but when i try build it did not show the desired output on the client-side terminal.
The server-side terminal does not react anything.
this is my code for server side:
import socket
import numpy as np
import encodings
HOST = '192.168.0.177' # Standard loopback interface address (localhost)
PORT = 65432 # Port to listen on (non-privileged ports are > 1023)
def random_data(): # ANY DATA YOU WANT TO SEND WRITE YOUR SENSOR CODE HERE
x1 = np.random.randint(0, 55, None) # Dummy temperature
y1 = np.random.randint(0, 45, None) # Dummy humidigy
my_sensor = "{},{}".format(x1,y1)
return my_sensor # return data seperated by comma
def my_server():
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
print("Server Started waiting for client to connect ")
s.bind((HOST, PORT))
s.listen(5)
conn, addr = s.accept()
with conn:
print('Connected by', addr)
while True:
data = conn.recv(1024).decode('utf-8')
if str(data) == "Data":
print("Ok Sending data ")
my_data = random_data()
x_encoded_data = my_data.encode('utf-8')
conn.sendall(x_encoded_data)
elif str(data) == "Quit":
print("shutting down server ")
break
if not data:
break
else:
pass
if __name__ == '__main__':
while 1:
my_server()
and this is my client code:
import socket
import threading
import time
HOST = '192.168.0.177' # The server's hostname or IP address
PORT = 65432 # The port used by the server
def process_data_from_server(x):
x1, y1 = x.split(",")
return x1,y1
def my_client():
threading.Timer(11, my_client).start()
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.connect((HOST, PORT))
my = input("Data")
my_inp = my.encode('utf-8')
s.sendall(my_inp)
data = s.recv(1024).decode('utf-8')
x_temperature,y_humidity = process_data_from_server(data)
print("Temperature {}".format(x_temperature))
print("Humidity {}".format(y_humidity))
s.close()
time.sleep(5)
if __name__ == "__main__":
while 1:
my_client()
I have tried many solution by printing "Data" directly to the terminal.
can anyone help me?
Ok, I have found the problem. I am using Sublime Text 3 when running the client.py script When i post in the build it doesnt response nothing. So I change my IDE to PYCharm and then it worked. I don't know why. I hope that's helpful to other people that have this problem. Thank you very much.
my raspberry pi is the server and Im trying to send continuous message from rpi to android while recieving a command from client (android app),i really dont know if this is possible and how to do it is out of my reach and it is not a feedback message here is my code hope you will help me thank you.
import apptopi
from socket import *
from time import ctime
from nanpy import (ArduinoApi, SerialManager)
apptopi.setup()
connection = SerialManager()
a = ArduinoApi(connection = connection)
ctrCmd = ['Up','Down','Left','Right','Stop','Connect']
add = 0
add += 1
a = str(add) //**this is a sample that i want to send continously
HOST = ''
PORT = 21567
BUFSIZE = 1024
ADDR = (HOST,PORT)
tcpSerSock = socket(AF_INET, SOCK_STREAM)
tcpSerSock.bind(ADDR)
tcpSerSock.listen(0)
tcpSerSock.send(str.encode(a)) <== i really don't know how to send
continuously
while True:
print 'Waiting for connection'
tcpCliSock,addr = tcpSerSock.accept()
print '...connected from :', addr
try:
while True:
data = ''
data = tcpCliSock.recv(BUFSIZE)
if not data:
break
if data == ctrCmd[0]:
apptopi.forw()
print 'forward'
if data == ctrCmd[1]:
apptopi.back()
print 'backward'
if data == ctrCmd[2]:
apptopi.left()
print 'leftturn'
if data == ctrCmd[3]:
apptopi.right()
print 'rightturn'
if data == ctrCmd[4]:
apptopi.stp()
print 'stop'
except KeyboardInterrupt:
apptopi.close()
GPIO.cleanup()
tcpSerSock.close();
OK one approach is to use the select() function for this. There is information in the documentation about its operation.
As an example I've made a modified version of your program (see below). I don't have a raspberry pi, so that part of the code is commented out, but you can replace it as needed.
The example uses the timeout feature of select() to send "continuous" messages to clients whilst also monitoring them for incoming messages. You can adjust the message contents and timeout to whatever works for you. NB you may also need to respond to client messages, as this code only sends data to clients after a timeout. Make whatever changes you need.
import sys
import socket
import select
ctrCmd = ['Up','Down','Left','Right','Stop','Connect']
HOST = ''
PORT = 21567
BUFSIZE = 1024
ADDR = (HOST,PORT)
tcpSerSock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
tcpSerSock.bind(ADDR)
tcpSerSock.listen(1)
print 'Waiting for connection'
sendInterval = 1.0 # interval(sec) for sending messages to connected clients
rxset = [tcpSerSock]
txset = []
while 1:
rxfds, txfds, exfds = select.select(rxset, txset, rxset, sendInterval)
if rxfds:
for sock in rxfds:
if sock is tcpSerSock:
# a client is connecting
tcpCliSock, addr = tcpSerSock.accept()
tcpCliSock.setblocking(0)
rxset.append(tcpCliSock)
print '...connected from :', addr
else:
# a client socket has data or has closed the connection
try:
data = sock.recv(BUFSIZE)
if not data:
print "...connection closed by remote end"
rxset.remove(sock)
sock.close()
else:
if data == ctrCmd[0]:
#apptopi.forw()
print 'forward'
if data == ctrCmd[1]:
#apptopi.back()
print 'backward'
if data == ctrCmd[2]:
#apptopi.left()
print 'leftturn'
if data == ctrCmd[3]:
#apptopi.right()
print 'rightturn'
if data == ctrCmd[4]:
#apptopi.stp()
print 'stop'
except:
print "...connection closed by remote end"
rxset.remove(sock)
sock.close()
else:
# timeout - send data to any active client
for sock in rxset:
if sock is not tcpSerSock:
sock.send("Hello!\n")
The simple client program I used to test this is here:
import sys
import socket
import time
ctrCmd = ['Up','Down','Left','Right','Stop','Connect']
HOST = '127.0.0.1'
PORT = 21567
BUFSIZE = 1024
ADDR = (HOST,PORT)
tcpCliSock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
tcpCliSock.connect(ADDR)
time.sleep(1)
for i in range(len(ctrCmd)):
tcpCliSock.send(ctrCmd[i])
time.sleep(1)
data = tcpCliSock.recv(BUFSIZE)
print data
tcpCliSock.close()
Hope this helps, best of luck.
Trying to make a server that tells the client what number he/she is. For example, once you connect it should say something like "Welcome client #5" or something along those lines. Right now I'm just trying to write it so that it simply reads a line in and echos it back. Im stuck on as far as getting it to show the clients number.
import socket
import sys
host = ''
port = 37373
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((host,port))
s.listen(1)
while 1:
s, address = s.accept()
data = s.recv(1024)
if data:
s.send(data)
s.close()
that is
import socket
import sys
Clinet_number = 0
host = ''
port = 37373
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((host,port))
s.listen(10) # number of queued connections
while 1:
Client_number += 1
s, address = s.accept()
data = s.recv(1024)
if data:
s.send(str(Client_number))
s.close()
I am writing a echo server and client in Python, that implements a simple number guessing game. I know how to multiplex using select, that's fine. The other server I wrote achieves this. But now I am writing a new server (which is fairly similar), however it accepts connections from two ports rather than one, one port for player client, and one for admin which I will use eventually for the who command, returning all connected players.
My problem is, that after sending the initial greetings message, the clients receive feedback from the server on the first send, recv. But after that I cannot send any more messages to server (nothing gets sent from the clients), I have been searching and playing around for hours, to no avail. Any help would be appreciated. Thanks!
# MULTIPLEX SERVER
import socket, select, time, random, ssl, sys, os
# VARS
EXP = 1
HOST = '127.0.0.1'
PORT_P = 4000
PORT_A = 4001
BUFFSZ = 1024
BKLOG = 5
GREETS = 'Greetings'
INPUTS = []
OUTPUTS = []
CLIENT_ADDRS = {}
CLIENT_ANS = {}
CLIENTS = ""
_adm_rtnMSG = 'Admin_Greetings'
# Function to determine how far the player is
# from the chosen random number
def Within(value, target):
diff = abs(target - value)
if diff > 3:
return 'Not even close, youth!'
else:
return 'Ooh, not to far: ' + str(diff) + ' away, keep trying...'
# END_FUNCTION
print('Server up and running...\n')
try:
for p in PORT_P, PORT_A:
INPUTS.append(socket.socket(socket.AF_INET, socket.SOCK_STREAM))
INPUTS[-1].setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
INPUTS[-1].bind((HOST, p))
INPUTS[-1].listen(BKLOG)
except socket.error(value, message):
if INPUTS[-1]:
INPUTS[-1].close()
INPUTS = INPUTS[:-1]
print('Failure to open socket: ' + message)
sys.exit(1)
while True:
READ_IO, WRITE_IO, ERROR = select.select(INPUTS, OUTPUTS, INPUTS)
for r in READ_IO:
for p in INPUTS:
if r is p:
(acpt_sock, addr) = p.accept()
print('Connection established with ', acpt_sock.getsockname())
CLIENT_ADDRS[acpt_sock] = addr
CLIENT_ANS[acpt_sock] = random.randrange(1, 20)
else:
data = acpt_sock.recv(BUFFSZ).decode()
acpt_sock.setblocking(0)
if data:
if 'Hello' in data:
print(CLIENT_ADDRS[acpt_sock], ' random number is: ', CLIENT_ANS[acpt_sock])
acpt_sock.send(b'Greetings\nGuess a random number between 1 & 20')
# drop elif here for admin cmd
elif 'Hi' in data:
acpt_sock.send(_adm_rtnMSG.encode())
else:
if int(data) == CLIENT_ANS[acpt_sock]:
acpt_sock.send(b'That was correct, Well done!')
else:
acpt_sock.send(str(Within(int(data), CLIENT_ANS[acpt_sock])).encode())
else:
print('Closing Connection # ', addr)
INPUTS.remove(acpt_sock)
acpt_sock.close()
del CLIENT_ADDRS[acpt_sock]
# PLAYER CLIENT
import socket
import re
# INIT VARS
HOST = '127.0.0.1'
PORT = 4000
INITSTR = 'Hello'
BUFF = 1024
# Set up socket
sender = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sender.connect((HOST, PORT))
sender.send(bytes((INITSTR), "ascii"))
print("Kirby Prompt FTW!\nConnected to Server via", HOST, "::", PORT, '\n')
rtnMSG = sender.recv(BUFF).decode()
print(rtnMSG)
# Simple loop to keep client alive
# to send and receive data from the server
while 'correct' not in rtnMSG:
_guess = input("(>',')> ")
sender.send(bytes((_guess), "ascii"))
rtnMSG = sender.recv(BUFF).decode()
print(rtnMSG)
sender.close()
# ADMIN CLIENT
import socket
import re
import ssl
# INIT VARS
HOST = '127.0.0.1'
PORT = 4001
INITSTR = 'Hi'
BUFF = 1024
# Set up socket
adm_sender = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
adm_sender.connect((HOST, PORT))
adm_sender.send(bytes((INITSTR), "ascii"))
print("Connected to Server as Admin via", HOST, "::", PORT, '\n')
rtnMSG = adm_sender.recv(BUFF).decode()
print(rtnMSG)
while True:
cmd = input('$ ')
adm_sender.send(bytes((cmd), "ascii"))
rtnMSG = adm_sender.recv(BUFF).decode()
print(rtnMSG)
adm_sender.close()