I'm having problems with a simple socket connection to an Heroku app.
This is my server:
import socket
import os
import time
import sys
server = socket.socket()
port = int(os.environ.get("PORT", 12344))
host = "0.0.0.0"
server.bind((host, port))
print(f"###### SERVER RUNNING ON PORT {port} ({host}) ######")
server.listen()
while True:
s, addr = server.accept()
print("Recived request from:", addr)
print(addr, " sent: ", repr(s.recv(1024)))
print("Answering to:", addr)
s.send("Hello, world! (from server)".encode())
print("Answered to:", addr)
s.close()
It builds and run perfectly on Heroku(it receives also socket connection, not from me...by at this time, I don't care much about it)
This is my client:
import socket
import sys
HOST = 'app_name.herokuapp.com/' # The server's hostname or IP address
PORT = int(sys.argv[1]) # The port used by the server
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
print("connecting to " + HOST +":"+str(PORT))
s.connect((HOST, PORT))
print(s)
s.sendall("HI!!!".encode())
data = s.recv(1024)
print('Received', repr(data))
Running the client, after a while it returns:
File "./client.py", line 14, in <module>
s.connect((HOST, PORT))
TimeoutError: [Errno 110] Connection timed out
I don't know how to connect to it...am I missing something?
The problem is linked to the fact that Heroku app allow only http(s) connections. I honesty didn't found any Heroku docs that conferm it but the Daniel Chin' answer to this question make sense to me.
However, move the server.py to AWS worked for me (EC2 with t2.micro is free for the first year!!)
Related
I'm trying to make a basic python networking program. All I'm trying to do is send strings of text back and forth between the server and the client. I'm trying to host the server on my Raspberry Pi, and connect with a client on Windows 10. The program works great locally on my computer, but when I try to connect to my server, it gives me ConnectionRefusedError: [WinError 10061] No connection could be made because the target machine actively refused it. My server code is as follows:
import socket # Import socket module
import netifaces as ni
s = socket.socket() # Create a socket object
host = socket.gethostname() # Get local machine name
port = 12345 # Reserve a port for your service.
s.bind((host, port))
#host_ip = ni.ifaddresses('wlan0')[ni.AF_INET][0]['addr']
host_ip = "bruh?"
print("Server started! \nHostname: " + host + " \nIP: " + host_ip + " \nPort: " + str(port))
s.listen() # Now wait for client connection.
while True:
c, addr = s.accept() # Establish connection with client.
print('Got connection from', addr)
output = "Welcome to the server!".encode()
c.send(output)
c.close()
Client code:
import socket
s = socket.socket()
host = 192.168.1.21
port = 12345
s.connect((host, int(port)))
noResponse = False
serverResponse = s.recv(1024).decode()
print(serverResponse)
s.close()
Does anyone know what my problem is? Thanks.
There may be a few reasons you are getting a ConnectionRefusedError, please try the following:
Check that no firewall is blocking your connection.
Double-check the server IP, if it is wrong you may get this error.
Try to use Hercules to check the connection.
Also, I would change the code as follow:
Server:
import socket
HOST = '' # localhost
PORT = # IMPORTANT !! Do not use reserved ports
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
sock.bind((HOST, PORT))
sock.listen()
conn, addr = sock.accept()
with conn:
print('Connected by', addr)
while True:
data = conn.recv(1024)
if not data:
break
print('Data: ',data)
conn.sendall('RT')
Client:
import socket
HOST = '' # server IP address
PORT = # server port
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
sock.connect((HOST, PORT))
sock.sendall('Hello, I am the Client')
data = sock.recv(1024)
print('Received', data)
By doing this you are using a TCP connection and you can test your code with different TCP server and client emulators.
I've recently been tinkering around with the python socket module and I have come across an issue.
Here is my python server side script (im using python3.8.2)
import socket
#defin socket object
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((socket.gethostname(), 0))
s.listen(5)
while True:
clientsocket, address = s.accept()
print(f"connection from client has been established")
clientsocket.send(bytes("welcome to the server!", "utf-8"))
My server side script runs fine, however when i run the client script
import socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((socket.gethostname(127.0.0.1), 0))
msg = s.recv(1024)
print(msg.decode("utf-8"))
i get the following:
File "client.py", line 3
s.connect((socket.gethostname(127.0.0.1), 0))
^
SyntaxError: invalid syntax
I've tried changing the IP to my computer host name and gives the following:
raceback (most recent call last):
File "client.py", line 3, in <module>
s.connect(socket.gethostname((LAPTOP-XXXXXXX), 0))
NameError: name 'LAPTOP' is not defined
There are multiple issues:
when specifying IP addresses and hostnames, they must be formatted as strings (e.g. "127.0.0.1" and "LAPTOP-XXXXXXX"). Specifying them without quotes causes Python to attempt to interpret them as other tokens, such as variable names, reserved keyword, numbers, etc., which fails causing erros such as SyntaxError and NameError.
socket.gethostname() does not take an argument
specifying port 0 in the socket.bind() call results in a random high numbered port being assigned, so you either need to hardcode the port you use or dynamically specify the correct port in your client (e.g. by specifying it as an argument when executing the program)
in the server code, socket.gethostname() may not end up using the loopback address. One option here is using an empty string, which results in accepting connections on any IPv4 address.
Here's a working implementation:
server.py
import socket
HOST = ''
PORT = 45555
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((HOST, PORT))
host_addr = s.getsockname()
print("listening on {}:{}".format(host_addr[0], host_addr[1]))
s.listen(5)
while True:
client_socket, client_addr = s.accept()
print("connection from {}:{} established".format(client_addr[0], client_addr[1]))
client_socket.send(bytes("welcome to the server!", "utf-8"))
client.py
import socket
HOST = '127.0.0.1'
PORT = 45555
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST, PORT))
msg = s.recv(1024)
print(msg.decode("utf-8"))
Output from the server:
$ python3 server.py
listening on 0.0.0.0:45555
connection from 127.0.0.1:51188 established
connection from 127.0.0.1:51244 established
Output from client:
$ python3 client.py
welcome to the server!
$ python3 client.py
welcome to the server!
Put the 127.0.0.1 as string in gethostname
In the /etc/hosts file content, You will have an IP address mapping with '127.0.1.1' to your hostname. This will cause the name resolution to get 127.0.1.1. Just comment this line. So Every one in your LAN can receive the data when they connect with your ip (192.168.1.*). Used threading to manage multiple Clients.
Here's the Server and Client Code:
Server Code:
import socket
import os
from threading import Thread
import threading
import time
import datetime
def listener(client, address):
print ("Accepted connection from: ", address)
with clients_lock:
clients.add(client)
try:
while True:
client.send(a)
time.sleep(2)
finally:
with clients_lock:
clients.remove(client)
client.close()
clients = set()
clients_lock = threading.Lock()
host = socket.getfqdn() # it gets ip of lan
port = 10016
s = socket.socket()
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind((host,port))
s.listen(3)
th = []
print ("Server is listening for connections...")
while True:
client, address = s.accept()
timestamp = datetime.datetime.now().strftime("%b %d %Y,%a, %I:%M:%S %p")
a = ("Hi Steven!!!" + timestamp).encode()
th.append(Thread(target=listener, args = (client,address)).start())
s.close()
Client Code:
import socket
import os
import time
s = socket.socket()
host = '192.168.1.43' #my server ip
port = 10016
print(host)
print(port)
s.connect((host, port))
while True:
print((s.recv(1024)).decode())
s.close()
Output:
(base) paulsteven#smackcoders:~$ python server.py
Server is listening for connections...
Accepted connection from: ('192.168.1.43', 38716)
(base) paulsteven#smackcoders:~$ python client.py
192.168.1.43
10016
Hi Steven!!!Feb 19 2020,Wed, 11:13:17 AM
Hi Steven!!!Feb 19 2020,Wed, 11:13:17 AM
Hi Steven!!!Feb 19 2020,Wed, 11:13:17 AM
I'm trying to develop a simple client/server application in python.
The client is running in a Docker container whereas the server is running directly on the host machine.
Here is the code of the client:
import socket
def main():
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect(('127.0.0.1', 8888))
print (Connected to server)
if __name__ == '__main__':
main()
and here is the code of the server:
import socket
HOST = '127.0.0.1'
PORT = 8888
print ("Serving on ", PORT)
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
s.bind((HOST, PORT))
s.listen()
conn, addr = s.accept()
with conn:
print('Connected by', addr)
I have the following error:
File "./main.py", line 5, in main
s.connect(('127.0.0.1', 8888))
ConnectionRefusedError: [Errno 111] Connection refused
If I run this client outside a container (directly on host machine), i can connect. But I have this error when I run it in a container.
PS: It's not pure Docker container but an IoT Edge module
Do you know what is the problem ?
Thanks
first s.connect(('127.0.0.1', 8888)) in the container means to connect to the container itself not the host, to make that works you should run your Container with --network=host
second Option is to supply your host IP address to the client:
s.connect(('HOST_ROUTABLE_IP_ADDRESS', 8888))
I am trying to create a simple web server with python using the following code.
However, When I run this code, I face this error:
ConnectionRefusedError: [WinError 10061] No connection could be made
because the target machine actively refused it
It worths mentioning that I have already tried some solutions suggesting manipulation of proxy settings in internet options. I have run the code both in the unticked and the confirmed situation of the proxy server and yet cannot resolve the issue.
Could you please guide me through this ?
import sys
import socketserver
import socket
hostname = socket.gethostname()
print("This is the host name: " + hostname)
port_number = 60000
soc = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
soc.connect((hostname,port_number))
Standard EXAMPLE of socket connection
SERVER & CLIENT
run this in your IDLE
import time
import socket
import threading
HOST = 'localhost' # Standard loopback interface address (localhost)
PORT = 60000 # Port to listen on (non-privileged ports are > 1023)
def server(HOST,PORT):
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((HOST, PORT))
s.listen(1)
while True:
conn, addr = s.accept()
data = conn.recv(1024)
if data:
print(data)
data = None
time.sleep(1)
print('Listening...')
def client(HOST,PORT,message):
print("This is the server's hostname: " + HOST)
soc = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
soc.connect((HOST,PORT))
soc.send(message)
soc.close()
th=threading.Thread(target = server,args = (HOST,PORT))
th.daemon = True
th.start()
After running this, in your IDLE execute this command and see response
>>> client(HOST,PORT,'Hello server, client sending greetings')
This is the server's hostname: localhost
Hello server, client sending greetings
>>>
If you try to do server with port 60000 but send message on different port, you will receive the same error as in your OP. That shows, that on that port is no server listening to connections
I learned sockets in python. When I tried to programming sockets script in one computer, it worked, but when I tried to programming sockets script with two different computers and open socket with connection, it didn't work.
One computer(the server):
import socket
s = socket.socket()
host = socket.gethostname()
port = 1234
s.bind((host, port))
s.listen(5)
while True:
c, addr = s.accept()
print 'Got connection from', addr
c.send('Thank you for connecting')
c.close()
Second computer(the client):
import socket
s = socket.socket()
host = raw_input("The ip you want to connect to: ")
port = 1234
s.connect((host, port))
print s.recv(1024)
Error:
socket.error: [Errno 10061]
What is the problem in the scripts? Why it doesn't work?
Errno 10061:
It means the server you are trying to connect to is not waiting for one.
Make sure you have the port number open.
Try killing all python processes and start server again.
Update
Instead of
host = socket.gethostname()
use
host = ""