Flutter how to connect to a socket, which I write a Python script as a server, this server side is like this:
import socket
import time
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.bind(("192.168.0.113", 9999))# 注意bind的这里，IP地址和端口号都要与前面的程序中一样
sock.listen(2)# 监听端口
# 等待数据源端连接
src, src_addr = sock.accept()
print "Source Connected by", src_addr
# 等待目标端连接
dst, dst_addr = sock.accept()
print "Destination Connected by", dst_addr
while True:
msg = src.recv(1024 *1024)
if not msg:
break
try:
dst.sendall(msg)
except Exception as ex:
dst, dst_addr = sock.accept()
print "Destination Connected Again by", dst_addr
except KeyboardInterrupt:
print "Interrupted"
break
src.close()
dst.close()
I wanna using Flutter to write a very simple client to show the image send from this python server via socket, how to achieve this?
I don't know about raw sockets but if you can use WebSockets in Python you could use the web_socket_channel package:
import 'package:web_socket_channel/io.dart';
import 'package:web_socket_channel/status.dart' as status;
main() async {
var channel = await IOWebSocketChannel.connect("ws://localhost:1234");
channel.stream.listen((message) {
channel.sink.add("received!");
channel.close(status.goingAway);
}, onDone: () => print("Stream closed"));
}
There's more info on using this here:
https://flutter.io/cookbook/networking/web-sockets/
Related
I'm trying to make a python socket client/server chat app, but can't seem to work around this error. I've used netstat -a|findstr 7000 to make sure the port was available, and it was. I don't have any antivirus running besides Windows Security. I also tried it after turning off all firewalls on my computer--have not messed with firewall settings in my router. I'm running both files in Anaconda Powershell Prompt as admin.
Any help is appreciated.
Code for server.py :
from socket import AF_INET, socket, SOCK_STREAM
import threading
BUFSIZ = 1024
FORMAT = 'utf-8'
SERVER = '192.168.1.10'
ADDR = (SERVER, 7000)
server = socket(AF_INET, SOCK_STREAM)
server.bind(ADDR)
sockets = {server}
clients = {}
def accept_incoming_connections():
while True:
client, client_addr = server.accept()
print ("%s:%s has connected." % client_addr)
client.send(bytes("Enter your name and press enter."), FORMAT)
sockets[client] = client_addr
# client_thread = threading.Thread(target=handle_client, args=(client,)).start()
def handle_client(client):
client_name = client.recv(BUFSIZ).decode(FORMAT)
client.send(bytes("Type .exit when you're ready to quit.", FORMAT))
msg = "%s has entered the chat." % client_name
broadcast(bytes(msg, FORMAT))
clients[client] = client_name
while True:
msg = client.recv(BUFSIZ)
if msg == bytes(".exit", FORMAT):
client.send(bytes(".exit", FORMAT))
client.close()
del clients[client]
broadcast(bytes("%s has left the chat." % client_name, FORMAT))
break
else:
broadcast(msg, client_name)
def broadcast(msg, name=""):
for client in clients:
client.send(bytes(name, FORMAT) + msg)
if __name__ == "__main__":
server.listen()
print("Awaiting connection.")
accept_incoming_connections()
Code for client.py :
import socket
import threading
BUFSIZ = 1024
FORMAT = 'utf-8'
SERVER = '192.168.1.10'
ADDR = (SERVER, 7000)
client_sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client_sock.connect(ADDR)
def receive():
msg = client_sock.recv(BUFSIZ).decode(FORMAT)
print(msg)
def send():
msg = input('Enter msg: ')
msg.encode(FORMAT)
client_sock.send(msg)
if msg == ".exit":
client_sock.close()
receive_thread = Thread(target=receive)
receive_thread.start()
EDIT: I fixed it. I set SERVER to 'localhost' and PORT to 9999 for both server and client.
I've problem with python socket at s.sendto(data,addr)
and my code like this
import socket
def Main():
host = '127.0.0.1'
port = 5000
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.bind((host, port))
print("server started")
while True:
data, addr = s.recvfrom(1024)
print ("message from : "+ str(addr))
print ("from connected user : "+ str(data))
data = str(data.upper())
print ("sending : "+ str(data))
socket.sendto(data, addr)
and result
socket.sendto(data, addr)
AttributeError: module 'socket' has no attribute 'sendto'
s.close()
if __name__ == '__main__':
Main()
and at UdpClient s.sendto is working
It seems that you mistyped the socket.sendto(... statement: The AttributeError is raised since the method sendto() is to be called from instances of the class socket.socket (as you have in s), and not from the socketmodule itself. See here for more details about the meaning of that statement.
So you basically need to change socket.sendto(... to s.sendto(...
also, if you want to check the attributes of any x object,(apart from reading the docs) you can simply check its x.__dict__ field, as explained here
cheers
i've written the following script on PyCharm IDE:
import socket
import time
sock = socket(socket.AF_INET, socket.SOCK_DGRAM)
hexpacket "00 FF"
ip = raw_input('Target IP: ')
port = input('Port: ')
duration = ('Number of seconds to send packets: ')
timeout = time.time() + duration
sent = 0
while True:
if time.time() > timeout:
break
else:
pass
sock.sendto(hexpacket,(ip,port))
sent = sent +1
print "Send %s packet to %s through ports %s"(send, ip, port)
I get an output from the console of:
TypeError: 'module' object is not callable
I have tried to change the "import socket" statement to either "from socket import socket" and "from socket import *" but both did not help.
I also tried to use "pip install socket" but I get "could not find any downloads that satisfy the requirement socket".
Any idea how do I solve this simple issue? I thought socket is a basic module that comes with every python download.
Thanks for the answers..!
sock = socket(socket.AF_INET, socket.SOCK_DGRAM)
you are using socket object directly it's wrong it's throwing an error
TypeError: 'module' object is not callable
Try this::
client_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
I've been working on a client for this chat server but I am running into a bit of a challenge. The server uses Python's 3.4RC1 asyncio module.
Behavior:
My client connects. My second client connects. Either can send messages to the server BUT, the server is not broadcasting them as it should in a normal public chat room.
User1: Hello. Presses Enter.
User2 does not see it.
User2: Anyone there? Presses Enter.
User2 sees User1: Hello. and User2: Anyone there?
Just... strange. Not sure what I'm missing.
Here are the files. Give it a try.
Server:
from socket import socket, SO_REUSEADDR, SOL_SOCKET
from asyncio import Task, coroutine, get_event_loop
class Peer(object):
def __init__(self, server, sock, name):
self.loop = server.loop
self.name = name
self._sock = sock
self._server = server
Task(self._peer_handler())
def send(self, data):
return self.loop.sock_send(self._sock, data.encode('utf-8'))
#coroutine
def _peer_handler(self):
try:
yield from self._peer_loop()
except IOError:
pass
finally:
self._server.remove(self)
#coroutine
def _peer_loop(self):
while True:
buf = yield from self.loop.sock_recv(self._sock, 1024)
if buf == b'':
break
self._server.broadcast('%s: %s' % (self.name, buf.decode('utf-8')))
class Server(object):
def __init__(self, loop, port):
self.loop = loop
self._serv_sock = socket()
self._serv_sock.setblocking(0)
self._serv_sock.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
self._serv_sock.bind(('',port))
self._serv_sock.listen(5)
self._peers = []
Task(self._server())
def remove(self, peer):
self._peers.remove(peer)
self.broadcast('Peer %s quit!' % (peer.name,))
def broadcast(self, message):
for peer in self._peers:
peer.send(message)
#coroutine
def _server(self):
while True:
peer_sock, peer_name = yield from self.loop.sock_accept(self._serv_sock)
peer_sock.setblocking(0)
peer = Peer(self, peer_sock, peer_name)
self._peers.append(peer)
self.broadcast('Peer %s connected!' % (peer.name,))
def main():
loop = get_event_loop()
Server(loop, 1234)
loop.run_forever()
if __name__ == '__main__':
main()
Client:
# import socket
from socket import *
# form socket import socket, bind, listen, recv, send
HOST = 'localhost' #localhost / 192.168.1.1
# LAN - 192.168.1.1
PORT = 1234
s = socket(AF_INET, SOCK_STREAM)# 98% of all socket programming will use AF_INET and SOCK_STREAM
s.connect((HOST, PORT))
while True:
message = input("Your Message: ")
encoded_msg = message.encode('utf-8')
s.send(encoded_msg)
print('Awaiting Reply..')
reply = s.recv(1024)
decoded_reply = reply.decode('utf-8')
decoded_reply = repr(decoded_reply)
print('Received ', decoded_reply)
s.close()
Here's the non threaded server code I wrote. works great but ONLY between 2 people. How could this code be updated to broadcast every message received to all clients connected?
# import socket
from socket import *
# form socket import socket, bind, listen, recv, send
HOST = 'localhost' #localhost / 192.168.1.1
# LAN - 192.168.1.1
PORT = 1234
s = socket(AF_INET, SOCK_STREAM) # 98% of all socket programming will use AF_INET and SOCK_STREAM
s.bind((HOST, PORT))
s.listen(5) # how many connections it can receive at one time
conn, addr = s.accept() # accept the connection
print('Connected by', addr) # print the address of the person connected
while True:
data = conn.recv(1024)
decoded_data = data.decode('utf-8')
data = repr(decoded_data)
print('Received ', decoded_data)
reply = input("Reply: ")
encoded_reply = reply.encode('utf-8')
conn.sendall(encoded_reply)
print('Server Started')
conn.close()
Okay, let’s think about what your client does. You ask for a message to send, blocking for user input. Then you send that message and receive whatever there is at the server. Afterwards, you block again, waiting for another message.
So when client A sends a text, client B is likely blocking for user input. As such, B won’t actually check if the server sent anything. It will only display what’s there after you have sent something.
Obviously, in a chat, you don’t want to block on user input. You want to continue receiving new messages from the server even if the user isn’t sending messages. So you need to separate those, and run both asynchronously.
I haven’t really done much with asyncio yet, so I don’t really know if this can be nicely done with it, but you essentially just need to put the reading and sending into two separate concurrent tasks, e.g. using threads or concurrent.futures.
A quick example of what you could do, using threading:
from socket import *
from threading import Thread
HOST = 'localhost'
PORT = 1234
s = socket(AF_INET, SOCK_STREAM)
s.connect((HOST, PORT))
def keepReading ():
try:
while True:
reply = s.recv(1024).decode()
print('Received ', reply)
except ConnectionAbortedError:
pass
t = Thread(target=keepReading)
t.start()
try:
while True:
message = input('')
s.send(message.encode())
except EOFError:
pass
finally:
s.close()
So I am working on an iPhone app that requires a socket to handle multiple clients for online gaming. I have tried Twisted, and with much effort, I have failed to get a bunch of info to be sent at once, which is why I am now going to attempt socket.
My question is, using the code below, how would you be able to have multiple clients connected? I've tried lists, but I just can't figure out the format for that. How can this be accomplished where multiple clients are connected at once and I am able to send a message to a specific client?
Thank you!
#!/usr/bin/python # This is server.py file
import socket # Import socket module
s = socket.socket() # Create a socket object
host = socket.gethostname() # Get local machine name
port = 50000 # Reserve a port for your service.
print 'Server started!'
print 'Waiting for clients...'
s.bind((host, port)) # Bind to the port
s.listen(5) # Now wait for client connection.
c, addr = s.accept() # Establish connection with client.
print 'Got connection from', addr
while True:
msg = c.recv(1024)
print addr, ' >> ', msg
msg = raw_input('SERVER >> ')
c.send(msg);
#c.close() # Close the connection
Based on your question:
My question is, using the code below, how would you be able to have multiple clients connected? I've tried lists, but I just can't figure out the format for that. How can this be accomplished where multiple clients are connected at once and I am able to send a message to a specific client?
Using the code you gave, you can do this:
#!/usr/bin/python # This is server.py file
import socket # Import socket module
import thread
def on_new_client(clientsocket,addr):
while True:
msg = clientsocket.recv(1024)
#do some checks and if msg == someWeirdSignal: break:
print addr, ' >> ', msg
msg = raw_input('SERVER >> ')
#Maybe some code to compute the last digit of PI, play game or anything else can go here and when you are done.
clientsocket.send(msg)
clientsocket.close()
s = socket.socket() # Create a socket object
host = socket.gethostname() # Get local machine name
port = 50000 # Reserve a port for your service.
print 'Server started!'
print 'Waiting for clients...'
s.bind((host, port)) # Bind to the port
s.listen(5) # Now wait for client connection.
print 'Got connection from', addr
while True:
c, addr = s.accept() # Establish connection with client.
thread.start_new_thread(on_new_client,(c,addr))
#Note it's (addr,) not (addr) because second parameter is a tuple
#Edit: (c,addr)
#that's how you pass arguments to functions when creating new threads using thread module.
s.close()
As Eli Bendersky mentioned, you can use processes instead of threads, you can also check python threading module or other async sockets framework. Note: checks are left for you to implement how you want and this is just a basic framework.
accept can continuously provide new client connections. However, note that it, and other socket calls are usually blocking. Therefore you have a few options at this point:
Open new threads to handle clients, while the main thread goes back to accepting new clients
As above but with processes, instead of threads
Use asynchronous socket frameworks like Twisted, or a plethora of others
Here is the example from the SocketServer documentation which would make an excellent starting point
import SocketServer
class MyTCPHandler(SocketServer.BaseRequestHandler):
"""
The RequestHandler class for our server.
It is instantiated once per connection to the server, and must
override the handle() method to implement communication to the
client.
"""
def handle(self):
# self.request is the TCP socket connected to the client
self.data = self.request.recv(1024).strip()
print "{} wrote:".format(self.client_address[0])
print self.data
# just send back the same data, but upper-cased
self.request.sendall(self.data.upper())
if __name__ == "__main__":
HOST, PORT = "localhost", 9999
# Create the server, binding to localhost on port 9999
server = SocketServer.TCPServer((HOST, PORT), MyTCPHandler)
# Activate the server; this will keep running until you
# interrupt the program with Ctrl-C
server.serve_forever()
Try it from a terminal like this
$ telnet localhost 9999
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Hello
HELLOConnection closed by foreign host.
$ telnet localhost 9999
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Sausage
SAUSAGEConnection closed by foreign host.
You'll probably need to use A Forking or Threading Mixin too
This program will open 26 sockets where you would be able to connect a lot of TCP clients to it.
#!usr/bin/python
from thread import *
import socket
import sys
def clientthread(conn):
buffer=""
while True:
data = conn.recv(8192)
buffer+=data
print buffer
#conn.sendall(reply)
conn.close()
def main():
try:
host = '192.168.1.3'
port = 6666
tot_socket = 26
list_sock = []
for i in range(tot_socket):
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.setsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR,1)
s.bind((host, port+i))
s.listen(10)
list_sock.append(s)
print "[*] Server listening on %s %d" %(host, (port+i))
while 1:
for j in range(len(list_sock)):
conn, addr = list_sock[j].accept()
print '[*] Connected with ' + addr[0] + ':' + str(addr[1])
start_new_thread(clientthread ,(conn,))
s.close()
except KeyboardInterrupt as msg:
sys.exit(0)
if __name__ == "__main__":
main()
def get_clients():
first_run = True
startMainMenu = False
while True:
if first_run:
global done
done = False
Thread(target=animate, args=("Waiting For Connection",)).start()
Client, address = objSocket.accept()
global menuIsOn
if menuIsOn:
menuIsOn = False # will stop main menu
startMainMenu = True
done = True
# Get Current Directory in Client Machine
current_client_directory = Client.recv(1024).decode("utf-8", errors="ignore")
# beep on connection
beep()
print(f"{bcolors.OKBLUE}\n***** Incoming Connection *****{bcolors.OKGREEN}")
print('* Connected to: ' + address[0] + ':' + str(address[1]))
try:
get_client_info(Client, first_run)
except Exception as e:
print("Error data received is not a json!")
print(e)
now = datetime.now()
current_time = now.strftime("%D %H:%M:%S")
print("* Current Time =", current_time)
print("* Current Folder in Client: " + current_client_directory + bcolors.WARNING)
connections.append(Client)
addresses.append(address)
if first_run:
Thread(target=threaded_main_menu, daemon=True).start()
first_run = False
else:
print(f"{bcolors.OKBLUE}* Hit Enter To Continue.{bcolors.WARNING}\n#>", end="")
if startMainMenu == True:
Thread(target=threaded_main_menu, daemon=True).start()
startMainMenu = False
#!/usr/bin/python
import sys
import os
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
port = 50000
try:
s.bind((socket.gethostname() , port))
except socket.error as msg:
print(str(msg))
s.listen(10)
conn, addr = s.accept()
print 'Got connection from'+addr[0]+':'+str(addr[1]))
while 1:
msg = s.recv(1024)
print +addr[0]+, ' >> ', msg
msg = raw_input('SERVER >>'),host
s.send(msg)
s.close()