gevent-websocket

gevent-websocket is a WebSocket library for the gevent networking library.

Features include:

• Integration on both socket level or using an abstract interface.
• RPC and PubSub framework using WAMP (WebSocket Application Messaging Protocol).
• Easily extendible using a simple WebSocket protocol plugin API

from geventwebsocket import WebSocketServer, WebSocketApplication, Resource

class EchoApplication(WebSocketApplication):
    def on_open(self):
        print "Connection opened"

    def on_message(self, message):
        self.ws.send(message)

    def on_close(self, reason):
        print reason

WebSocketServer(
    ('', 8000),
    Resource({'/': EchoApplication})
).serve_forever()

or a low level implementation:

from gevent import pywsgi
from geventwebsocket.handler import WebSocketHandler

def websocket_app(environ, start_response):
    if environ["PATH_INFO"] == '/echo':
        ws = environ["wsgi.websocket"]
        message = ws.receive()
        ws.send(message)

server = pywsgi.WSGIServer(("", 8000), websocket_app,
    handler_class=WebSocketHandler)
server.serve_forever()

More examples can be found in the examples directory. Hopefully more documentation will be available soon.

Installation

The easiest way to install gevent-websocket is directly from PyPi using pip or setuptools by running the commands below:

$ pip install gevent-websocket

Gunicorn Worker

Using Gunicorn it is even more easy to start a server. Only the websocket_app from the previous example is required to start the server. Start Gunicorn using the following command and worker class to enable WebSocket funtionality for the application.

gunicorn -k "geventwebsocket.gunicorn.workers.GeventWebSocketWorker" wsgi:websocket_app

Performance

gevent-websocket is pretty fast, but can be accelerated further by installing wsaccel and ujson or simplejson:

$ pip install wsaccel ujson

gevent-websocket automatically detects wsaccell and uses the Cython implementation for UTF8 validation and later also frame masking and demasking.

Get in touch

Get in touch on IRC #gevent on Freenode or on the Gevent mailinglist. Issues can be created on Bitbucket.