Test bed for what is now Tornadose
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Using Tornado websockets for the publish/subscribe pattern
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| ### Python ### | |
| # Byte-compiled / optimized / DLL files | |
| __pycache__/ | |
| *.py[cod] | |
| *$py.class | |
| # C extensions | |
| *.so | |
| # Distribution / packaging | |
| .Python | |
| env/ | |
| build/ | |
| develop-eggs/ | |
| dist/ | |
| downloads/ | |
| eggs/ | |
| .eggs/ | |
| lib/ | |
| lib64/ | |
| parts/ | |
| sdist/ | |
| var/ | |
| *.egg-info/ | |
| .installed.cfg | |
| *.egg | |
| # PyInstaller | |
| # Usually these files are written by a python script from a template | |
| # before PyInstaller builds the exe, so as to inject date/other infos into it. | |
| *.manifest | |
| *.spec | |
| # Installer logs | |
| pip-log.txt | |
| pip-delete-this-directory.txt | |
| # Unit test / coverage reports | |
| htmlcov/ | |
| .tox/ | |
| .coverage | |
| .coverage.* | |
| .cache | |
| nosetests.xml | |
| coverage.xml | |
| *,cover | |
| # Translations | |
| *.mo | |
| *.pot | |
| # Django stuff: | |
| *.log | |
| # Sphinx documentation | |
| docs/_build/ | |
| # PyBuilder | |
| target/ |
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| <!doctype html> | |
| <html lang="en"> | |
| <head> | |
| <meta charset="utf-8"> | |
| <title>Tornado Websocket Pubsub</title> | |
| <meta name="description" content="Tornado Websocket Pubsub"> | |
| <meta name="author" content="Michael V. DePalatis"> | |
| <!--[if lt IE 9]> | |
| <script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script> | |
| <![endif]--> | |
| <script src="pubsub.js"></script> | |
| </head> | |
| <body> | |
| <div id="placeholder"></div> | |
| </body> | |
| </html> |
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| var socket, | |
| url = window.location; | |
| function connect() { | |
| socket = new WebSocket('ws://' + url.host + '/socket'); | |
| socket.onmessage = function (msg) { | |
| var data = JSON.parse(msg.data), | |
| html = data.value.toString() + ' '; | |
| document.querySelector('#placeholder').innerHTML += html; | |
| console.log(data.value); | |
| }; | |
| } | |
| window.onload = function () { | |
| connect(); | |
| }; | |
| window.onbeforeunload = function () { | |
| socket.close(); | |
| }; |
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| """A demonstration of using websockets for pubsub-like functionality in | |
| Tornado. | |
| """ | |
| import random | |
| from tornado import gen | |
| from tornado.options import options, define | |
| from tornado.ioloop import IOLoop | |
| from tornado.web import Application, RequestHandler, StaticFileHandler | |
| from tornado.websocket import WebSocketHandler, WebSocketClosedError | |
| from tornado.queues import Queue | |
| class Publisher(object): | |
| """Handles new data to be passed on to subscribers.""" | |
| def __init__(self): | |
| self.messages = Queue() | |
| self.subscribers = set() | |
| def register(self, subscriber): | |
| """Register a new subscriber.""" | |
| self.subscribers.add(subscriber) | |
| def deregister(self, subscriber): | |
| """Stop publishing to a subscriber.""" | |
| self.subscribers.remove(subscriber) | |
| @gen.coroutine | |
| def submit(self, message): | |
| """Submit a new message to publish to subscribers.""" | |
| yield self.messages.put(message) | |
| @gen.coroutine | |
| def publish(self): | |
| while True: | |
| message = yield self.messages.get() | |
| if len(self.subscribers) > 0: | |
| print("Pushing message {} to {} subscribers...".format( | |
| message, len(self.subscribers))) | |
| yield [subscriber.submit(message) for subscriber in self.subscribers] | |
| class MainHandler(RequestHandler): | |
| """Renders the main template for displaying messages to subscribers.""" | |
| def get(self): | |
| self.render('index.html') | |
| class Subscription(WebSocketHandler): | |
| """Websocket for subscribers.""" | |
| def initialize(self, publisher): | |
| self.publisher = publisher | |
| self.messages = Queue() | |
| self.finished = False | |
| def open(self): | |
| print("New subscriber.") | |
| self.publisher.register(self) | |
| self.run() | |
| def on_close(self): | |
| self._close() | |
| def _close(self): | |
| print("Subscriber left.") | |
| self.publisher.deregister(self) | |
| self.finished = True | |
| @gen.coroutine | |
| def submit(self, message): | |
| yield self.messages.put(message) | |
| @gen.coroutine | |
| def run(self): | |
| while not self.finished: | |
| message = yield self.messages.get() | |
| print("New message: " + str(message)) | |
| self.send(message) | |
| def send(self, message): | |
| try: | |
| self.write_message(dict(value=message)) | |
| except WebSocketClosedError: | |
| self._close() | |
| @gen.coroutine | |
| def generate_data(publisher): | |
| while True: | |
| data = random.randint(0, 9) | |
| yield publisher.submit(data) | |
| yield gen.sleep(random.randint(0, 2)) | |
| @gen.coroutine | |
| def main(): | |
| define('port', default=8080) | |
| options.parse_command_line() | |
| publisher = Publisher() | |
| app = Application( | |
| [ | |
| ('/((\w*).js)', StaticFileHandler, dict(path='.')), | |
| ('/', MainHandler), | |
| ('/socket', Subscription, dict(publisher=publisher)) | |
| ] | |
| ) | |
| app.listen(options.port) | |
| yield [publisher.publish(), generate_data(publisher)] | |
| if __name__ == "__main__": | |
| IOLoop.instance().run_sync(main) |
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