Basic authentication with Tornado. Tornado doesn't provide a good documentation when you try to handle your own login service. I tried to do mine My new gist : https://gist.github.com/guillaumevincent/4771570

gistfile1.py

import tornado.auth
import tornado.escape
import tornado.httpserver
import tornado.ioloop
import tornado.options
import tornado.web
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/", LoginHandler),
            (r"/auth/logout/", LogoutHandler),
            (r"/sb/", ScubabookHandler),
            ]
        settings = dict(
            template_path=Settings.TEMPLATE_PATH,
            static_path=Settings.STATIC_PATH,
            debug=Settings.DEBUG,
            cookie_secret=Settings.COOKIE_SECRET
            )
        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 user_json:
            return tornado.escape.json_decode(user_json)
        else:
            return None


class MainHandler(tornado.web.RequestHandler):

    def get(self):
        try:
            errormessage = self.get_argument("error")
        except:
            errormessage = ""
        self.render("index.html", errormessage = errormessage)


class LoginHandler(BaseHandler):

    def check_permission(self, password, username):
        if username == "admin" and password == "admin":
            return True
        return False

    def post(self):
        username = self.get_argument("username", "")
        password = self.get_argument("password", "")
        auth = self.check_permission(password, username)
        if auth:
            self.set_current_user(username)
            self.redirect(self.get_argument("next", u"/sb/"))
        else:
            error_msg = u"?error=" + tornado.escape.url_escape("Login incorrect")
            self.redirect(u"/" + error_msg)

    def set_current_user(self, user):
        if user:
            self.set_secure_cookie("user", tornado.escape.json_encode(user))
        else:
            self.clear_cookie("user")

class LogoutHandler(BaseHandler):

    def get(self):
        self.clear_cookie("user")
        self.redirect(u"/")

class ScubabookHandler(tornado.web.RequestHandler):

    def get_current_user(self):
        return self.get_secure_cookie("user")

    def get(self):
        if not self.current_user:
            self.redirect("/")
            return
        username = self.current_user
        self.write('Hi there, '+ username)

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()