Files
jupyterhub/jupyterhub/handlers/base.py
MinRK 53edc0b2f7 add a notion of admin users
and an @admin_only decorator for restricted methods
2014-09-14 11:54:05 -07:00

297 lines
9.2 KiB
Python

"""HTTP Handlers for the hub server"""
# Copyright (c) Jupyter Development Team.
# Distributed under the terms of the Modified BSD License.
import json
import re
try:
# py3
from http.client import responses
except ImportError:
from httplib import responses
import requests
from jinja2 import TemplateNotFound
from tornado.log import app_log
from tornado.httputil import url_concat
from tornado.web import RequestHandler
from tornado import gen, web
from .. import orm
from ..spawner import LocalProcessSpawner
from ..utils import wait_for_server, url_path_join
# pattern for the authentication token header
auth_header_pat = re.compile(r'^token\s+([^\s]+)$')
class BaseHandler(RequestHandler):
"""Base Handler class with access to common methods and properties."""
@property
def log(self):
"""I can't seem to avoid typing self.log"""
return self.settings.get('log', app_log)
@property
def config(self):
return self.settings.get('config', None)
@property
def base_url(self):
return self.settings.get('base_url', '/')
@property
def db(self):
return self.settings['db']
@property
def hub(self):
return self.settings['hub']
#---------------------------------------------------------------
# Login and cookie-related
#---------------------------------------------------------------
@property
def admin_users(self):
return self.settings.setdefault('admin_users', set())
def get_current_user_token(self):
"""get_current_user from Authorization header token"""
auth_header = self.request.headers.get('Authorization', '')
match = auth_header_pat.match(auth_header)
if not match:
return None
token = match.group(1)
orm_token = self.db.query(orm.APIToken).filter(orm.APIToken.token == token).first()
if orm_token is None:
return None
else:
return orm_token.user
def get_current_user_cookie(self):
"""get_current_user from a cookie token"""
token = self.get_cookie(self.hub.server.cookie_name, None)
if token:
cookie_token = self.db.query(orm.CookieToken).filter(
orm.CookieToken.token==token).first()
if cookie_token:
return cookie_token.user
else:
# have cookie, but it's not valid. Clear it and start over.
self.clear_cookie(self.hub.server.cookie_name, path=self.hub.server.base_url)
def get_current_user(self):
"""get current username"""
user = self.get_current_user_token()
if user is not None:
return user
return self.get_current_user_cookie()
def user_from_username(self, username):
"""Get ORM User for username"""
user = self.db.query(orm.User).filter(orm.User.name==username).first()
if user is None:
admin = (not self.admin_users) or username in self.admin_users
user = orm.User(name=username, admin=admin)
self.db.add(user)
self.db.commit()
return user
def clear_login_cookie(self):
user = self.get_current_user()
if user and user.server:
self.clear_cookie(user.server.cookie_name, path=user.server.base_url)
self.clear_cookie(self.hub.server.cookie_name, path=self.hub.server.base_url)
def set_login_cookies(self, user):
"""Set login cookies for the Hub and single-user server."""
# create and set a new cookie token for the single-user server
cookie_token = user.new_cookie_token()
self.db.add(cookie_token)
self.db.commit()
self.set_cookie(
user.server.cookie_name,
cookie_token.token,
path=user.server.base_url,
)
# create and set a new cookie token for the hub
cookie_token = user.new_cookie_token()
self.db.add(cookie_token)
self.db.commit()
self.set_cookie(
self.hub.server.cookie_name,
cookie_token.token,
path=self.hub.server.base_url)
@gen.coroutine
def authenticate(self, data):
auth = self.settings.get('authenticator', None)
if auth is not None:
result = yield auth.authenticate(self, data)
raise gen.Return(result)
else:
self.log.error("No authentication function, login is impossible!")
#---------------------------------------------------------------
# spawning-related
#---------------------------------------------------------------
@property
def spawner_class(self):
return self.settings.get('spawner_class', LocalProcessSpawner)
@gen.coroutine
def notify_proxy(self, user):
proxy = self.db.query(orm.Proxy).first()
r = requests.post(
url_path_join(
proxy.api_server.url,
user.server.base_url,
),
data=json.dumps(dict(
target=user.server.host,
user=user.name,
)),
headers={'Authorization': "token %s" % proxy.auth_token},
)
yield wait_for_server(user.server.ip, user.server.port)
r.raise_for_status()
@gen.coroutine
def spawn_single_user(self, user):
user.server = orm.Server(
cookie_name='%s-%s' % (self.hub.server.cookie_name, user.name),
cookie_secret=self.hub.server.cookie_secret,
base_url=url_path_join(self.base_url, 'user', user.name),
)
self.db.add(user.server)
self.db.commit()
api_token = user.new_api_token()
self.db.add(api_token)
self.db.commit()
spawner = user.spawner = self.spawner_class(
config=self.config,
user=user,
hub=self.hub,
api_token=api_token.token,
)
yield spawner.start()
# store state
user.state = spawner.get_state()
self.db.commit()
self.notify_proxy(user)
raise gen.Return(user)
#---------------------------------------------------------------
# template rendering
#---------------------------------------------------------------
def get_template(self, name):
"""Return the jinja template object for a given name"""
return self.settings['jinja2_env'].get_template(name)
def render_template(self, name, **ns):
ns.update(self.template_namespace)
template = self.get_template(name)
return template.render(**ns)
@property
def logged_in(self):
"""Is a user currently logged in?"""
return self.get_current_user() is not None
@property
def template_namespace(self):
return dict(
base_url=self.hub.server.base_url,
logged_in=self.logged_in,
login_url=self.settings['login_url'],
static_url=self.static_url,
)
def write_error(self, status_code, **kwargs):
"""render custom error pages"""
exc_info = kwargs.get('exc_info')
message = ''
status_message = responses.get(status_code, 'Unknown HTTP Error')
if exc_info:
exception = exc_info[1]
# get the custom message, if defined
try:
message = exception.log_message % exception.args
except Exception:
pass
# construct the custom reason, if defined
reason = getattr(exception, 'reason', '')
if reason:
status_message = reason
# build template namespace
ns = dict(
status_code=status_code,
status_message=status_message,
message=message,
exception=exception,
)
self.set_header('Content-Type', 'text/html')
# render the template
try:
html = self.render_template('%s.html' % status_code, **ns)
except TemplateNotFound:
self.log.debug("No template for %d", status_code)
html = self.render_template('error.html', **ns)
self.write(html)
class Template404(BaseHandler):
"""Render our 404 template"""
def prepare(self):
raise web.HTTPError(404)
class RootHandler(BaseHandler):
"""Render the Hub root page."""
@web.authenticated
def get(self):
user = self.get_current_user()
html = self.render_template('index.html',
server_running = user.server is not None,
server_url = '/user/%s' % user.name,
)
self.finish(html)
class UserHandler(BaseHandler):
"""Respawn single-user server after logging in.
This handler shouldn't be called if the proxy is set up correctly.
"""
@web.authenticated
def get(self, name):
self.log.warn("Hub serving single-user url: %s", self.request.path)
current_user = self.get_current_user()
if current_user and current_user.name == name:
self.spawn_single_user(current_user)
self.redirect('')
else:
self.log.warn("Hub serving single-user url: %s", self.request.path)
self.clear_login_cookie()
self.redirect(url_concat(self.settings['login_url'], {
'next' : self.request.path,
}))