voctocore/controlserver.py



import socket, threading, queue
from gi.repository import GObject

def controlServerEntrypoint(f):
    # mark the method as something that requires view's class
    f.is_control_server_entrypoint = True
    return f

class ControlServer():
    def __init__(self, videomix):
        '''Initialize server and start listening.'''
        self.videomix = videomix

        sock = socket.socket()
        sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        sock.bind(('0.0.0.0', 23000))
        sock.listen(1)

        # register socket for callback inside the GTK-Mainloop
        GObject.io_add_watch(sock, GObject.IO_IN, self.listener)

    def listener(self, sock, *args):
        '''Asynchronous connection listener. Starts a handler for each connection.'''
        conn, addr = sock.accept()
        print("Connection from ", addr)

        # register data-received handler inside the GTK-Mainloop
        GObject.io_add_watch(conn, GObject.IO_IN, self.handler)
        return True

    def handler(self, conn, *args):
        '''Asynchronous connection handler. Processes each line from the socket.'''
        line = conn.recv(4096)
        if not len(line):
            print("Connection closed.")
            return False

        r = self.processLine(line.decode('utf-8'))
        if isinstance(r, str):
            conn.send((r+'\n').encode('utf-8'))
            return False

        conn.send('OK\n'.encode('utf-8'))
        return True


    def processLine(self, line):
        command, argstring = (line.strip()+' ').split(' ', 1)
        args = argstring.strip().split()
        print(command, args)

        if not hasattr(self.videomix, command):
            return 'unknown command {}'.format(command)

        f = getattr(self.videomix, command)
        if not hasattr(f, 'is_control_server_entrypoint'):
            return 'method {} not callable from controlserver'.format(command)

        try:
            return f(*args)
        except Exception as e:
            return str(e)