Built on top of
asyncio, Python's standard asynchronous I/O framework, it
provides an elegant coroutine-based API.
Here's how a client sends and receives messages:
#!/usr/bin/env python import asyncio import websockets async def hello(uri): async with websockets.connect(uri) as websocket: await websocket.send("Hello world!") await websocket.recv() asyncio.get_event_loop().run_until_complete( hello('ws://localhost:8765'))
And here's an echo server:
#!/usr/bin/env python import asyncio import websockets async def echo(websocket, path): async for message in websocket: await websocket.send(message) asyncio.get_event_loop().run_until_complete( websockets.serve(echo, 'localhost', 8765)) asyncio.get_event_loop().run_forever()
Does that look good?
Professionally supported websockets is now available
Tidelift gives software development teams a single source for purchasing and maintaining their software, with professional grade assurances from the experts who know it best, while seamlessly integrating with existing tools.
(If you contribute to ``websockets`` and would like to become an official support provider, let me know.)
Why should I use
The development of
websockets is shaped by four principles:
- Simplicity: all you need to understand is
msg = await ws.recv()and
websocketstakes care of managing connections so you can focus on your application.
websocketsis built for production; for example it was the only library to handle backpressure correctly before the issue became widely known in the Python community.
websocketsis heavily tested. Continuous integration fails under 100% branch coverage. Also it passes the industry-standard Autobahn Testsuite.
- Performance: memory use is configurable. An extension written in C accelerates expensive operations. It's pre-compiled for Linux, macOS and Windows and packaged in the wheel format for each system and Python version.
Documentation is a first class concern in the project. Head over to Read the Docs and see for yourself.
Why shouldn't I use
- If you prefer callbacks over coroutines:
websocketswas created to provide the best coroutine-based API to manage WebSocket connections in Python. Pick another library for a callback-based API.
- If you're looking for a mixed HTTP / WebSocket library:
websocketsaims at being an excellent implementation of RFC 6455: The WebSocket Protocol and RFC 7692: Compression Extensions for WebSocket. Its support for HTTP is minimal — just enough for a HTTP health check.
- If you want to use Python 2:
asynciowhich only works on Python 3.
websocketsrequires Python ≥ 3.6.
Bug reports, patches and suggestions are welcome!
To report a security vulnerability, please use the Tidelift security contact. Tidelift will coordinate the fix and disclosure.
Participants must uphold the Contributor Covenant code of conduct.
websockets is released under the BSD license.