Google OAuth2 using Tornado Web Framework

server.py

#!/usr/bin/env python
# encoding: utf-8
"""
server.py

Created by John Wesonga on 2011-12-12.
Copyright (c) 2011 __MyCompanyName__. All rights reserved.
"""

import tornado.auth
from tornado import httpclient
import tornado.escape
import tornado.httputil
import tornado.ioloop
import tornado.web
import tornado.httpserver
import uimodules

# import oauth2
import urllib
import logging
import os
import settings

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"/auth/login", AuthHandler),
    (r"/auth/logout", LogoutHandler),
    (r"/profile", ProfileHandler),
    ]

    settings = {"static_path": os.path.join(os.path.dirname(__file__), "static"),
                "cookie_secret": "32oETzKXQAGaYdkL5gEmGeJJFuYh7EQnp2XdTP1o",
                "login_url": "/auth/login",
                "google_permissions": "https://www.googleapis.com/auth/userinfo.profile https://www.googleapis.com/auth/userinfo.email https://www.googleapis.com/auth/calendar",
                "debug": True,
                "template_path": "templates/",
                "xsrf_cookies": True,
                "ui_modules": uimodules,
                }


    tornado.web.Application.__init__(self, handlers, **settings)

class BaseHandler(tornado.web.RequestHandler):
  def get_current_user(self):
    user_json = self.get_secure_cookie("user")
    if not user_json: return None
    return tornado.escape.json_decode(user_json)

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

class ProfileHandler(BaseHandler):
  @tornado.web.authenticated
  def get(self):
    http_client = httpclient.HTTPClient()
    try:
      response = http_client.fetch("https://www.googleapis.com/oauth2/v1/userinfo?alt=json&access_token=" +
            self.current_user["access_token"])
      logging.info(response.body)
      profile_info = response.body
    except httpclient.HTTPError as e:
      logging.error(e)
    self.render('profile.html',
      profile=tornado.escape.json_decode(profile_info))
    http_client.close()

class AuthHandler(BaseHandler, tornado.auth.GoogleOAuth2Mixin):
  @tornado.gen.coroutine
  def get(self):
    if self.get_argument('code', False):
      user = yield self.get_authenticated_user(redirect_uri='http://localhost:8888/auth/login',
       code=self.get_argument('code'),
       callback = self._on_auth)

    else:
      yield self.authorize_redirect(
        redirect_uri='http://localhost:8888/auth/login',
        client_id=settings.config['google_oauth']['key'],
        scope=['profile', 'email'],
        response_type='code',
        extra_params={'approval_prompt': 'auto'},
        )

  def _on_auth(self, user_info):
    self.set_secure_cookie("user", tornado.escape.json_encode(user_info))
    self.redirect('/profile')

class LogoutHandler(BaseHandler):
  def get(self):
    logging.info("cookie " + self.get_secure_cookie("user"))
    self.clear_cookie("user")
    self.redirect("/")

def main():
  tornado.options.parse_command_line()
  http_server = tornado.httpserver.HTTPServer(Application())
  http_server.listen(options.port)
  tornado.ioloop.IOLoop.instance().start()

if __name__ == '__main__':
  main()