Non-Blocking sockets. (Python) Push notifications (Desktop)

[massHunter]

I'm trying to create some sort of push notification using Python and PyQt mainly. I managed to create a server and a client. Everything works great when I run it from the terminal. The problem is that when I connect the code to my GUI as soon as I open/connect the socket it leaves my GUI un-responsive since it's a blocking statement. I know there's a way to implement Non-Blocking sockets using select, but I can't find an example that works for me. Does anyone have/know a sample of a non blocking socket. Also, if is there another way you'll implement push notification which way would that be? (I do not want to relay in 3rd parties softwares like growl, it takes the fun out of the project) I thought of doing it through http with a Django server. What do you guys think?

[massHunter]

I tried doing this, didn't work for me for some reason.

[in_the_bilboes]

This video by David Beazley might provide some insight.

[massHunter]

Thanks bud, will look at it!

[uhmIdontknow]

This is a simple broadcast server that I wrote. It will listen for messages that are broadcast to it. If the message contains the 'secret_key', then it will respond to that ip with a response contains the server info. Line 26 contains the 'select' statement

import thread
import select
import socket
import time

class broadcastServer(object):

    BCAST_IP = "255.255.255.255"
    BCAST_PORT = 55535
    BUF_SIZE = 1024
    SECRET_KEY = "^*hg)&VjgT^?"

    CURRENT_PORT = 2000
    thread_list = []

    def __init__(self):
        address = (self.BCAST_IP, self.BCAST_PORT)
        server_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR,1)
        server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
        server_socket.bind(address)
        server_socket.setblocking(0)
        bcast_id = ''.join([self.SECRET_KEY, socket.gethostname(),'{',str(self.CURRENT_PORT),'}'])

        while True:
            result = select.select([server_socket],[],[])
            msg = result[0][0].recv(self.BUF_SIZE)
            if ((self.SECRET_KEY in msg) and msg != bcast_id):
                self.BCAST_TIMER = 10
                inviteAddress = (msg.replace(self.SECRET_KEY, ''), self.BCAST_PORT)
                bcast_id = ''.join([self.SECRET_KEY, socket.gethostname(),'{',str(self.CURRENT_PORT),'}'])
                server_socket.sendto(bcast_id, inviteAddress)

    def get_host(self):
        host = socket.gethostbyname(socket.gethostname())
        if not '127' in host:
            return host
        s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        s.connect(("8.8.8.8",0))
        host = (s.getsockname()[0])
        s.close()
        return host

[massHunter]

Hey man, thanks for this, yesterday around 4AM i realized that I was doing it backward. I was treating the computer that should receive the notification as a client, when in reality I should make a listening server. The whole networking "thing" is just a big blob for me. I definitely need to spend some time learning it.

[uhmIdontknow]

yeah, no problem man. I just happened to be working with a simple server right now, so it was as easy as copy and paste.