[Python] How to Async send and receive websocket messages with python

How do you send and receive messages using pythons asyncio and the websockets library? I am using Django Channels as the socket server. So basically I am trying to send and receive from this socket server.

I can easily send messages to my websocket server using:

#!/usr/bin/python3

async def main():
uri = f"{wsPrefix}stream/{machineSerial}/?{token}"
async with websockets.connect(uri, ping_interval = None) as websocket:
try:
cap = acapture.open(0)
except:
asyncio.sleep(1)
cap = acapture.open(0)
while True:
check,frame = cap.read()
if not websocket.open:
print("### reconnecting ###")
await websockets.connect(uri,ping_interval = None)
if check:
frame = cv2.cvtColor(frame,cv2.COLOR_BGR2RGB)
check, jpeg = cv2.imencode('.jpg', frame)
frame = jpeg.tobytes()
frame = bytearray(frame)
await websocket.send(frame)
await asyncio.sleep(0.05)


if __name__ == "__main__":
import websockets
import asyncio
import acapture
import cv2
from deviceSpecificVals import machineSerial, token
import deviceSpecificVals.url

urlPrefix = deviceSpecificVals.url
wsPrefix = deviceSpecificVals.wsPrefix

asyncio.run(main())


But how can you add another async function here to always be listening for a message? I want the receiver to finish the script and close when it receives a 'close' message.

I tried:

#!/usr/bin/python3

async def connect():
uri = f"{wsPrefix}stream/{machineSerial}/?{token}"
async with websockets.connect(uri, ping_interval = None) as websocket:
return websocket


async def rcv(websocket):
while True:
msg = await websocket.recv()
print(f"< {msg}")

async def send(websocket):
uri = f"{wsPrefix}stream/{machineSerial}/?{token}"
try:
cap = acapture.open(0)
except:
asyncio.sleep(1)
cap = acapture.open(0)
while True:
check,frame = cap.read()
if not websocket.open:
print("### reconnecting ###")
await websockets.connect(uri,ping_interval = None)
if check:
frame = cv2.cvtColor(frame,cv2.COLOR_BGR2RGB)
check, jpeg = cv2.imencode('.jpg', frame)
frame = jpeg.tobytes()
frame = bytearray(frame)
await websocket.send(frame)
await asyncio.sleep(0.05)

async def main():
websocket = await connect()
asyncio.ensure_future(send(websocket))
asyncio.ensure_future(rcv(websocket))
await asyncio.sleep(100000)

if __name__ == "__main__":
import websockets
import asyncio
import acapture
import cv2
from deviceSpecificVals import machineSerial, token
import deviceSpecificVals.url

urlPrefix = deviceSpecificVals.url
wsPrefix = deviceSpecificVals.wsPrefix

asyncio.run(main())


This will not connect to websocket, it is almost as if the connect function is not returning the websocket object. I am also very new to async, and trying to understand what is happening here

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