Python 3 Threaded websockets server

Question

I\'m building a Websocket server application in python 3. I\'m using this implementation: https://websockets.readthedocs.io/

Basically I want to manage multiple client.

Answer 1

Finally I got it ! It required Python 3.5.1 (while my distro provide only 3.4.3) and some help from Aymeric, the author of the websockets library (thanks to him).

#!/usr/bin/env python3
import signal, sys
sys.path.append('.')
import time
import websockets
import asyncio
import threading


stopFlag = False



class GPSWorker (threading.Thread):
  def __init__(self):
    threading.Thread.__init__(self)
    self.data = 0
    self.lastData = 0
    self.inc = 0

  # Simulate GPS data
  def run(self):
    while not stopFlag:
      self.data = self.inc
      self.inc += 1
      time.sleep(1)

  def get(self):
    if self.lastData is not self.data:
      self.lastData = self.data
      return self.data



class IMUWorker (threading.Thread):
  def __init__(self):
    threading.Thread.__init__(self)
    self.data = 0
    self.lastData = 0
    self.inc = 0

  # Simulate IMU data
  def run(self):
    while not stopFlag:
      self.data = self.inc
      self.inc += 1
      time.sleep(0.04)

  def get(self):
    if self.lastData is not self.data:
      self.lastData = self.data
      return self.data



class MSGWorker (threading.Thread):
  def __init__(self):
    threading.Thread.__init__(self)
    self.connected = set()

  def run(self):
    while not stopFlag:
      data = gpsWorker.get()
      if data:
        self.sendData('{"GPS": "%s"}' % data)

      data = imuWorker.get()
      if data:
        self.sendData('{"IMU": "%s"}' % data)

      time.sleep(0.04)

  async def handler(self, websocket, path):
    self.connected.add(websocket)
    try:
      await websocket.recv()
    except websockets.exceptions.ConnectionClosed:
      pass
    finally:
      self.connected.remove(websocket)

  def sendData(self, data):
    for websocket in self.connected.copy():
      print("Sending data: %s" % data)
      coro = websocket.send(data)
      future = asyncio.run_coroutine_threadsafe(coro, loop)



if __name__ == "__main__":
  print('aeroPi server')
  gpsWorker = GPSWorker()
  imuWorker = IMUWorker()
  msgWorker = MSGWorker()

  try:
    gpsWorker.start()
    imuWorker.start()
    msgWorker.start()

    ws_server = websockets.serve(msgWorker.handler, '0.0.0.0', 7700)
    loop = asyncio.get_event_loop()
    loop.run_until_complete(ws_server)
    loop.run_forever()
  except KeyboardInterrupt:
    stopFlag = True
    #TODO: close ws server and loop correctely
    print("Exiting program...")

Regards, Clément