Source code for session_security.middleware

"""
SessionSecurityMiddleware is the heart of the security that this application
attemps to provide.

To install this middleware, add to your ``settings.MIDDLEWARE_CLASSES``::

    'session_security.middleware.SessionSecurityMiddleware'

Make sure that it is placed **after** authentication middlewares.
"""

import time
from datetime import datetime, timedelta

from django import http
from django.contrib.auth import logout
from django.core.urlresolvers import reverse

from .utils import get_last_activity, set_last_activity
from .settings import EXPIRE_AFTER, PASSIVE_URLS


[docs]class SessionSecurityMiddleware(object): """ In charge of maintaining the real 'last activity' time, and log out the user if appropriate. """ def is_passive_request(self, request): return request.path in PASSIVE_URLS
[docs] def process_request(self, request): """ Update last activity time or logout. """ if not request.user.is_authenticated(): return now = datetime.now() self.update_last_activity(request, now) delta = now - get_last_activity(request.session) if delta >= timedelta(seconds=EXPIRE_AFTER): logout(request) elif not self.is_passive_request(request): set_last_activity(request.session, now)
[docs] def update_last_activity(self, request, now): """ If ``request.GET['idleFor']`` is set, check if it refers to a more recent activity than ``request.session['_session_security']`` and update it in this case. """ if '_session_security' not in request.session: set_last_activity(request.session, now) last_activity = get_last_activity(request.session) server_idle_for = (now - last_activity).seconds if (request.path == reverse('session_security_ping') and 'idleFor' in request.GET): # Gracefully ignore non-integer values try: client_idle_for = int(request.GET['idleFor']) except ValueError: return # Disallow negative values, causes problems with delta calculation if client_idle_for < 0: client_idle_for = 0 if client_idle_for < server_idle_for: # Client has more recent activity than we have in the session last_activity = now - timedelta(seconds=client_idle_for) # Update the session set_last_activity(request.session, last_activity)