Pure Python, pure state-machine WebSocket implementation

This repository contains a pure-Python implementation of a WebSocket protocol stack. It's written from the ground up to be embeddable in whatever program you choose to use, ensuring that you can communicate via WebSockets, as defined in RFC6455, regardless of your programming paradigm.

This repository does not provide a parsing layer, a network layer, or any rules about concurrency. Instead, it's a purely in-memory solution, defined in terms of data actions and WebSocket frames. RFC6455 and Compression Extensions for WebSocket via RFC7692 are fully supported.

wsproto supports Python 3.6.1 or higher.

To install it, just run:

$ pip install wsproto

Usage

Let's assume you have some form of network socket available. wsproto client connections automatically generate a HTTP request to initiate the WebSocket handshake. To create a WebSocket client connection:

from wsproto import WSConnection, ConnectionType
from wsproto.events import Request

ws = WSConnection(ConnectionType.CLIENT)
ws.send(Request(host='echo.websocket.org', target='/'))

To create a WebSocket server connection:

from wsproto.connection import WSConnection, ConnectionType

ws = WSConnection(ConnectionType.SERVER)

Every time you send a message, or call a ping, or simply if you receive incoming data, wsproto might respond with some outgoing data that you have to send:

some_socket.send(ws.bytes_to_send())

Both connection types need to receive incoming data:

ws.receive_data(some_byte_string_of_data)

And wsproto will issue events if the data contains any WebSocket messages or state changes:

for event in ws.events():
    if isinstance(event, Request):
        # only client connections get this event
        ws.send(AcceptConnection())
    elif isinstance(event, CloseConnection):
        # guess nobody wants to talk to us any more...
    elif isinstance(event, TextMessage):
        print('We got text!', event.data)
    elif isinstance(event, BytesMessage):
        print('We got bytes!', event.data)

Take a look at our docs for a full list of events <https://wsproto.readthedocs.io/en/latest/api.html#events>!

Documentation

Documentation is available at https://wsproto.readthedocs.io/en/latest/.

Contributing

wsproto welcomes contributions from anyone! Unlike many other projects we are happy to accept cosmetic contributions and small contributions, in addition to large feature requests and changes.

Before you contribute (either by opening an issue or filing a pull request), please read the contribution guidelines.