netcontroller.py

from __future__ import division
from past.utils import old_div
import time
import logging as log
import zmq

from PyQt5 import QtCore, QtNetwork

USE_ZMQ = False


class NetController(QtCore.QObject):

    ready_to_read = QtCore.pyqtSignal()
    data_received = QtCore.pyqtSignal(list)
    start = QtCore.pyqtSignal()

    def __init__(self, app):
        super(NetController, self).__init__()
        self.context = None
        self.socket = None
        self.app = app
        self.updates = 0
        self.packets = 0
        self.in_frame = False
        self.running = True
        self.last_time = time.clock()

        if USE_ZMQ:
            self.context = zmq.Context()
            self.socket = self.context.socket(zmq.SUB)
            self.socket.connect("tcp://localhost:3020")
            self.socket.setsockopt_string(zmq.SUBSCRIBE, u"")
            self.start.connect(self.run)
        else:
            self.socket = QtNetwork.QUdpSocket(self)
            self.socket.readyRead.connect(self.read_datagrams)
            self.socket.bind(3020, QtNetwork.QUdpSocket.ShareAddress | QtNetwork.QUdpSocket.ReuseAddressHint)

    @QtCore.pyqtSlot()
    def read_datagrams(self):
        while self.socket.hasPendingDatagrams():
            datagram = QtCore.QByteArray()
            datagram.resize(self.socket.pendingDatagramSize())
            (datagram, sender, sport) = self.socket.readDatagram(datagram.size())
            # TODO(JE): is this the best way for Py2/Py3 compatability?
            if type(datagram) is bytes:
                packet = [c for c in datagram]
            else:
                packet = [ord(c) for c in datagram.data()]
            self.packets += 1
            self.data_received.emit(packet)

    @QtCore.pyqtSlot()
    def run(self):
        while self.running:
            packets = self.socket.recv_multipart()
            for packet in packets:
                self.data_received.emit(packet)
                self.packets += 1
            QtCore.QCoreApplication.processEvents()

    def frame_started(self):
        self.in_frame = True

    @QtCore.pyqtSlot()
    def frame_complete(self):
        self.in_frame = False
        self.updates += 1

    def get_stats(self):
        dt = time.clock() - self.last_time
        if dt == 0:
            return 0
        ups = old_div(self.updates, dt)
        pps = old_div(self.packets, dt)
        self.last_time = time.clock()
        self.updates = 0
        self.packets = 0
        return {'pps': pps, 'ups': ups}