1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465 |
- """
- Cached, database-backed sessions.
- """
-
- from django.conf import settings
- from django.contrib.sessions.backends.db import SessionStore as DBStore
- from django.core.cache import caches
-
- KEY_PREFIX = "django.contrib.sessions.cached_db"
-
-
- class SessionStore(DBStore):
- """
- Implement cached, database backed sessions.
- """
- cache_key_prefix = KEY_PREFIX
-
- def __init__(self, session_key=None):
- self._cache = caches[settings.SESSION_CACHE_ALIAS]
- super().__init__(session_key)
-
- @property
- def cache_key(self):
- return self.cache_key_prefix + self._get_or_create_session_key()
-
- def load(self):
- try:
- data = self._cache.get(self.cache_key)
- except Exception:
- # Some backends (e.g. memcache) raise an exception on invalid
- # cache keys. If this happens, reset the session. See #17810.
- data = None
-
- if data is None:
- s = self._get_session_from_db()
- if s:
- data = self.decode(s.session_data)
- self._cache.set(self.cache_key, data, self.get_expiry_age(expiry=s.expire_date))
- else:
- data = {}
- return data
-
- def exists(self, session_key):
- return session_key and (self.cache_key_prefix + session_key) in self._cache or super().exists(session_key)
-
- def save(self, must_create=False):
- super().save(must_create)
- self._cache.set(self.cache_key, self._session, self.get_expiry_age())
-
- def delete(self, session_key=None):
- super().delete(session_key)
- if session_key is None:
- if self.session_key is None:
- return
- session_key = self.session_key
- self._cache.delete(self.cache_key_prefix + session_key)
-
- def flush(self):
- """
- Remove the current session data from the database and regenerate the
- key.
- """
- self.clear()
- self.delete(self.session_key)
- self._session_key = None
|