The Complete Guide to Python WebSocket Library (2025 Edition)

1import asyncio
2import websockets
3
4async def echo(websocket, path):
5    async for message in websocket:
6        await websocket.send(f"Echo: {message}")
7
8start_server = websockets.serve(echo, "localhost", 8765)
9asyncio.get_event_loop().run_until_complete(start_server)
10asyncio.get_event_loop().run_forever()
11

1import websocket
2
3ws = websocket.create_connection("ws://localhost:8765/")
4ws.send("Hello, WebSocket!")
5print(ws.recv())
6ws.close()
7

1import asyncio
2import websockets
3
4async def handler(websocket, path):
5    name = await websocket.recv()
6    await websocket.send(f"Hello, {name}!")
7
8start_server = websockets.serve(handler, "0.0.0.0", 9000)
9
10asyncio.get_event_loop().run_until_complete(start_server)
11asyncio.get_event_loop().run_forever()
12

1import threading
2import asyncio
3import websockets
4
5def start_ws_server():
6    async def handler(websocket, path):
7        async for message in websocket:
8            await websocket.send(f"Echo: {message}")
9    loop = asyncio.new_event_loop()
10    asyncio.set_event_loop(loop)
11    server = websockets.serve(handler, "localhost", 8001)
12    loop.run_until_complete(server)
13    loop.run_forever()
14
15server_thread = threading.Thread(target=start_ws_server)
16server_thread.start()
17

1import websocket
2
3def on_message(ws, message):
4    print(f"Received: {message}")
5
6def on_open(ws):
7    ws.send("Hello from websocket-client!")
8
9ws = websocket.WebSocketApp(
10    "ws://localhost:9000/",
11    on_open=on_open,
12    on_message=on_message
13)
14ws.run_forever()
15

1async def handler(websocket, path):
2    async for message in websocket:
3        await websocket.send(f"Processed: {message}")
4

1async def handler(websocket, path):
2    try:
3        async for message in websocket:
4            await websocket.send(f"Ack: {message}")
5    except websockets.exceptions.ConnectionClosed:
6        print("Connection closed")
7

1import ssl
2import websockets
3
4ssl_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
5ssl_context.load_cert_chain(certfile="cert.pem", keyfile="key.pem")
6
7start_server = websockets.serve(handler, "0.0.0.0", 443, ssl=ssl_context)
8