konamicode.py

import os

from tornado.websocket import WebSocketHandler
from tornado.web import RequestHandler, StaticFileHandler, Application, url
from tornado.escape import json_decode
from tornado import ioloop

from rx.subjects import Subject

UP, DOWN, LEFT, RIGHT, B, A = 38, 40, 37, 39, 66, 65
codes = [UP, UP, DOWN, DOWN, LEFT, RIGHT, LEFT, RIGHT, B, A]

class WSHandler(WebSocketHandler):
    def open(self):
        print("WebSocket opened")

        # A Subject is both an observable and observer, so we can both subscribe
        # to it and also feed (on_next) it with new values
        self.subject = Subject()

        # Now we take on our magic glasses and project the stream of bytes into
        # a ...
        query = (self.subject
                 # 1. stream of keycodes
                 .map(lambda obj: obj["keycode"])
                 # 2. stream of windows (10 ints long)
                 .window_with_count(10, 1)
                 # 3. stream of booleans, True or False
                 .flat_map(lambda win: win.sequence_equal(codes))
                 # 4. stream of Trues
                 .filter(lambda equal: equal)
                )
        # 4. we then subscribe to the Trues, and signal Konami! if we see any
        query.subscribe_(lambda x: self.write_message("Konami!"))

    def on_message(self, message):
        obj = json_decode(message)
        self.subject.on_next(obj)

    def on_close(self):
        print("WebSocket closed")

class MainHandler(RequestHandler):
    def get(self):
        self.render("index.html")

def main():
    port = os.environ.get("PORT", 8080)
    app = Application([
        url(r"/", MainHandler),
        (r'/ws', WSHandler),
        (r'/static/(.*)', StaticFileHandler, {'path': "."})
    ])
    print("Starting server at port: %s" % port)
    app.listen(port)
    ioloop.IOLoop.current().start()

if __name__ == '__main__':
    main()