WebSocket technology enables low-latency, full-duplex channels between a client and a server, making it ideal for syncing fast-changing game state in Minecraft. Unlike regular HTTP requests, a WebSocket connection stays open — so player coordinates, chat messages, or custom events can be pushed in real time with sub-50ms round-trip latency, instead of waiting on repeated polling.
Here's a minimal setup to get a Python WebSocket server talking to game clients.
1. A basic WebSocket server
Using the websockets library, you can spin up a server that broadcasts player events to everyone connected.
import asyncio
import json
import websockets
connected_clients = set()
async def handler(websocket):
connected_clients.add(websocket)
try:
async for message in websocket:
data = json.loads(message)
print(f"Received: {data}")
for client in connected_clients:
if client != websocket:
await client.send(message)
finally:
connected_clients.remove(websocket)
async def main():
async with websockets.serve(handler, "0.0.0.0", 8765):
await asyncio.Future()
asyncio.run(main())
2. Sending player position updates
On the client (or mod) side, you send small JSON payloads whenever a player moves.
import asyncio
import json
import websockets
async def send_position(x, y, z):
async with websockets.connect("ws://localhost:8765") as ws:
await ws.send(json.dumps({
"type": "position",
"player": "Steve",
"x": x, "y": y, "z": z
}))
3. Keeping connections alive
Game sessions can run for hours, so use ping/pong heartbeats to detect dropped clients early and avoid stale connections eating up server resources.
async with websockets.serve(
handler, "0.0.0.0", 8765,
ping_interval=20, ping_timeout=10
):
await asyncio.Future()
Why WebSocket over HTTP polling: polling means the client keeps asking "anything new?" every second, wasting bandwidth and adding latency. WebSocket flips that — the server pushes updates the instant something changes, which matters a lot for anything involving player movement, combat timing, or live chat.
Side note: if you're syncing large payloads like world snapshots or mod configs between servers, that's a different problem than real-time state — a no-account tool like SimpleDrop is handy for quickly passing those files around without setting up extra infra.
Thanks for reading — stay tuned for more posts on real-time game infrastructure with Python. 🎮
