Adds rolling session refresh middleware (#130)

babybuddy/middleware.py

@@ -1,5 +1,8 @@
+import time
+
 import pytz
 
+from django.conf import settings
 from django.utils import timezone
 
 
@@ -19,3 +22,24 @@ class UserTimezoneMiddleware:
             except pytz.UnknownTimeZoneError:
                 pass
         return self.get_response(request)
+
+class RollingSessionMiddleware:
+    """
+    Periodically resets the session expiry.
+    """
+    def __init__(self, get_response):
+        self.get_response = get_response
+
+    def __call__(self, request):
+        session_refresh = request.session.get('session_refresh')
+        if session_refresh:
+            try:
+                delta = int(time.time()) - session_refresh
+            except:
+                delta = settings.ROLLING_SESSION_REFRESH + 1
+            if delta > settings.ROLLING_SESSION_REFRESH:
+                request.session['session_refresh'] = int(time.time())
+                request.session.set_expiry(settings.SESSION_COOKIE_AGE)
+        else:
+            request.session['session_refresh'] = int(time.time())
+        return self.get_response(request)

babybuddy/settings/base.py

@@ -58,6 +58,7 @@ MIDDLEWARE = [
     'django.middleware.security.SecurityMiddleware',
     'whitenoise.middleware.WhiteNoiseMiddleware',
     'django.contrib.sessions.middleware.SessionMiddleware',
+    'babybuddy.middleware.RollingSessionMiddleware',
     'django.middleware.locale.LocaleMiddleware',
     'babybuddy.middleware.UserTimezoneMiddleware',
     'django.middleware.common.CommonMiddleware',
@@ -223,6 +224,10 @@ IMPORT_EXPORT_IMPORT_PERMISSION_CODE = 'add'
 IMPORT_EXPORT_EXPORT_PERMISSION_CODE = 'change'
 IMPORT_EXPORT_USE_TRANSACTIONS = True
 
+# Rolling session refreshes
+# How often to refresh the session
+ROLLING_SESSION_REFRESH = 86400
+
 # Baby Buddy configuration
 # See README.md#configuration for details about these settings.