| #!/usr/bin/env python |
| # |
| # Copyright 2009 Facebook |
| # |
| # Licensed under the Apache License, Version 2.0 (the "License"); you may |
| # not use this file except in compliance with the License. You may obtain |
| # a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the |
| # License for the specific language governing permissions and limitations |
| # under the License. |
| """Simplified chat demo for websockets. |
| |
| Authentication, error handling, etc are left as an exercise for the reader :) |
| """ |
| |
| import logging |
| import tornado.escape |
| import tornado.ioloop |
| import tornado.options |
| import tornado.web |
| import tornado.websocket |
| import os.path |
| import uuid |
| |
| from tornado.options import define, options |
| |
| define("port", default=8888, help="run on the given port", type=int) |
| |
| |
| class Application(tornado.web.Application): |
| def __init__(self): |
| handlers = [ |
| (r"/", MainHandler), |
| (r"/chatsocket", ChatSocketHandler), |
| ] |
| settings = dict( |
| cookie_secret="43oETzKXQAGaYdkL5gEmGeJJFuYh7EQnp2XdTP1o/Vo=", |
| template_path=os.path.join(os.path.dirname(__file__), "templates"), |
| static_path=os.path.join(os.path.dirname(__file__), "static"), |
| xsrf_cookies=True, |
| autoescape=None, |
| ) |
| tornado.web.Application.__init__(self, handlers, **settings) |
| |
| |
| class MainHandler(tornado.web.RequestHandler): |
| def get(self): |
| self.render("index.html", messages=ChatSocketHandler.cache) |
| |
| class ChatSocketHandler(tornado.websocket.WebSocketHandler): |
| waiters = set() |
| cache = [] |
| cache_size = 200 |
| |
| def allow_draft76(self): |
| # for iOS 5.0 Safari |
| return True |
| |
| def open(self): |
| ChatSocketHandler.waiters.add(self) |
| |
| def on_close(self): |
| ChatSocketHandler.waiters.remove(self) |
| |
| @classmethod |
| def update_cache(cls, chat): |
| cls.cache.append(chat) |
| if len(cls.cache) > cls.cache_size: |
| cls.cache = cls.cache[-cls.cache_size:] |
| |
| @classmethod |
| def send_updates(cls, chat): |
| logging.info("sending message to %d waiters", len(cls.waiters)) |
| for waiter in cls.waiters: |
| try: |
| waiter.write_message(chat) |
| except: |
| logging.error("Error sending message", exc_info=True) |
| |
| def on_message(self, message): |
| logging.info("got message %r", message) |
| parsed = tornado.escape.json_decode(message) |
| chat = { |
| "id": str(uuid.uuid4()), |
| "body": parsed["body"], |
| } |
| chat["html"] = self.render_string("message.html", message=chat) |
| |
| ChatSocketHandler.update_cache(chat) |
| ChatSocketHandler.send_updates(chat) |
| |
| |
| def main(): |
| tornado.options.parse_command_line() |
| app = Application() |
| app.listen(options.port) |
| tornado.ioloop.IOLoop.instance().start() |
| |
| |
| if __name__ == "__main__": |
| main() |