Closed socket from time to time

[dorinand]

Issue:

Hi, I am using this library and from time to time, I have registered that my websocket stopped working. I tried to debug it, and find out, socket is missing but no error message is logged.

Now, lets show some example. I dockerized (the same problem was discovered even when the application was not dockerized) my application and find out via netstat command, I have opened socket with destination port 443:

docker exec mywebsocket /bin/netstat -tpn
tcp        0      0 172.23.0.13:56340      1.2.3.4:443       ESTABLISHED 1/python3

When I check it with my websocket app that did not receive any messages for a long time, I find out there is no opened socket, but also no errors in output (I checked docker logs and also my app logs):

docker exec mywebsocket /bin/netstat -tpn 

My fix:

I implemented function check_websocket_connection() and insert it inside while loop after sleep:

import os
import psutil
import logging

logger = logging.getLogger()

process = psutil.Process(os.getpid())

def check_websocket_connection():
    for connection in process.connections():
        if connection.raddr.port == 443 and connection.status == 'ESTABLISHED':
            logger.debug('Connections on port 433 is established.')
            return True
        
        return False

while True:
    # Do other things in the meantime here...
    time.sleep(1)
    if not check_websocket_connection():
        logger.error('Missing socket')
        break 

It check every second if there exists some connection with destination port 443 created by programs PID. I know, it can't be used if PID use more than one connection with port 443, but I need only this connection so it works.

This is just snippet, I created whole class with logging, I hope I did not make any mistake here.

It works for now, but is there a better way how to solve it?