why is gevent-websocket synchronous?

Question

I am playing with gevent and websockets. This is a simple echo server:

from gevent.pywsgi import WSGIServer
from geventwebsocket.handler import WebSocketHand         


        

Answer 1

The actual problem is this: data = ws.receive()

What is happening here is your websocket is now waiting for a SINGLE connection while the whole app just hangs out.

You have two solutions, either add a timeout to ws.receive() OR set it up as a high level application:

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()

as exampled here: https://pypi.python.org/pypi/gevent-websocket/

This would then setup your process totally async, thus sending and receiving wouldn't compete for the same resource.