Tornado is a Python web framework that can handle high concurrency loads. The document discusses using Tornado and Nginx together to handle 17,000 requests per second. It provides examples of building simple and secure cookie-based authentication in Tornado as well as handling blocking vs non-blocking requests to external APIs. The document also briefly mentions ideas for further optimizations like templates, project structure, and pre-rendering frequently updated data.

1. globo Tornado + Nginx = 17k req/s
.com

2. two servers, one goal

3. ‣ huge potential userbase
‣ live sports events
1.000.000 ‣
‣
changing business model
unknown user behavior
‣ “beta” - small investment
‣ gotta keep it simple!

4. “It's time for web servers to handle ten thousand clients simultaneously,
don't you think? After all, the web is a big place now.”

5. as simple as you need - as robust as you want
nginx nginx tornado mongo
frontend backend
filer
filesystem

6. ‣ “there’s a lot of caching”
‣ scores, current transmissions etc. are updated quickly
‣ out of bounds to the general public - closed beta
‣ authentication and authorization from separate systems
‣ just checking if cookies exist on the frontend

7. import tornado.ioloop
import tornado.web
‣ plain Python class MainHandler(tornado.web.RequestHandler):
def get(self):
‣ good looking Python self.write("Hello, world")
‣ sweet! application = tornado.web.Application([
(r"/", MainHandler),
])
‣ fast!
if __name__ == "__main__":
‣ ab req/s: 2987.96 application.listen(8888)
tornado.ioloop.IOLoop.instance().start()

8. import json
import tornado.ioloop
import tornado.web
import tornado.httpclient
search = 'http://search.twitter.com/search.json?
‣ non-blocking web server q=pythonbrasil&result_type=mixed&count=1'
class MainHandler(tornado.web.RequestHandler):
‣ so please don’t block it! def get(self):
self.write("Hello blocking Twitter!n")
http_client = tornado.httpclient.HTTPClient()
‣ the blocking way... response = http_client.fetch(search)
last_tweet = json.loads(response.body)['results'][0]['text']
self.write(last_tweet)
‣ ab req/s: 0.81 application = tornado.web.Application([
(r"/", MainHandler),
(over our poor local wi-fi) ])
if __name__ == "__main__":
application.listen(8888)
tornado.ioloop.IOLoop.instance().start()

9. import json
import tornado.ioloop
import tornado.web
import tornado.httpclient
from tornado.web import asynchronous
search = 'http://search.twitter.com/search.json?
q=pythonbrasil&result_type=mixed&count=1'
‣ the non-blocking way... class MainHandler(tornado.web.RequestHandler):
‣ ab req/s: 7.25 @asynchronous
def get(self):
self.write("Hello blocking Twitter!n")
(over our poor local wi-fi) http_client = tornado.httpclient.AsyncHTTPClient()
response = http_client.fetch(search, self.handle_response)
def handle_response(self, response):
last_tweet = json.loads(response.body)['results'][0]['text']
self.finish(last_tweet)
application = tornado.web.Application([
(r"/", MainHandler),
])
if __name__ == "__main__":
application.listen(8888)
tornado.ioloop.IOLoop.instance().start()

10. import tornado.ioloop
import tornado.web
from db import users
class HomeHandler(tornado.web.RequestHandler):
def get(self):
if 'signed_in' == self.get_secure_cookie('access'):
self.write('Hello to your world!')
else:
self. write('Hello, world!')
‣ secure cookies class SigninHandler(tornado.web.RequestHandler):
def post(self):
if self.get_attribute('login') in users:
‣ not persisted self.set_secure_cookie('access', 'signed_in',
expires_days=None)
self.redirect('/')
‣ served from any class SignoutHandler(tornado.web.RequestHandler):
def get(self):
instance self.clear_cookie('access')
self.redirect('/')
application = tornado.web.Application([
(r"/", HomeHandler), (r"/signin", SigninHandler),
(r"/signout", SignoutHandler),
], **{
'cookie_secret': 'i_should_be_reading_that_from_env'
})
if __name__ == "__main__":
application.listen(8888)
tornado.ioloop.IOLoop.instance().start()

11. ‣ what else?
‣ templates extensions
‣ semi-standardized project structure
‣ pre-rendered data for frequently updated data - scores

12. ‣ most URLs are served as fast
as nginx can
‣ on a single 24 processors
17.000 server our load tests got us
to 17k req/s served by
Tornado
‣ few pages with heavy DB
access served less than 4k
req/s

13. Valeu!
Danilo Moret - Globo.com / Webmedia / Vídeos 3
moret@corp.globo.com - http://moret.pro.br/ - @moret1979