I am running two loops asynchronously, and want both to have access to the same websocket connection. One function periodic_fetch()
fetches some data periodically (every 60 seconds) and sends a message to the websocket if a condition is met. The other retrieve_websocket()
receives messages from the websocket and perform some action if a condition is met. As of now, I connect to the websocket in both functions, but that means retrieve_websocket()
will not receive the response to the websocket message sent by periodic_fetch()
. How do I create one websocket connection and use the same one in both loops as they run asynchronously? My code:
# Imports
import asyncio
import websockets
from datetime import datetime
websocket_url = "wss://localhost:5000/"
# Simulate fetching some data
async def fetch_data():
print("Fetching started")
await asyncio.sleep(2)
return {"data": 2}
# Receive and analyze websocket data
async def retrieve_websocket():
async with websockets.connect(websocket_url) as ws:
while True:
msg = await ws.recv()
print(msg)
# Perform some task if condition is met
# Periodically fetch data and send messages to websocket
async def periodic_fetch():
async with websockets.connect(websocket_url) as ws:
while True:
print(datetime.now())
fetch_task = asyncio.create_task(fetch_data())
wait_task = asyncio.create_task(asyncio.sleep(60))
res = await fetch_task
# Send message to websocket
await ws.send("Websocket message")
# Wait the remaining wait duration
await wait_task
loop = asyncio.get_event_loop()
cors = asyncio.wait([periodic_fetch(), retrieve_websocket()])
loop.run_until_complete(cors)
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Answer
The solution was to open the connection in a separate function and use asyncio.gather()
passing in the two functions with the websocket as parameter.
async def run_script():
async with websockets.connect(websocket_url) as ws:
await asyncio.gather(periodic_fetch(ws), retrieve_websocket(ws))
asyncio.run(run_script())