import datetime from django.conf import settings from django.contrib.sessions.models import Session from django.contrib.sessions.backends.base import SessionBase, CreateError from django.core.exceptions import SuspiciousOperation from django.db import IntegrityError, transaction, DEFAULT_DB_ALIAS from django.utils.encoding import force_unicode class SessionStore(SessionBase): """ Implements database session store. """ def __init__(self, session_key=None): self.using = getattr(settings, "SESSION_DB_ALIAS", DEFAULT_DB_ALIAS) super(SessionStore, self).__init__(session_key) def load(self): try: s = Session.objects.get( session_key = self.session_key, expire_date__gt=datetime.datetime.now() ) return self.decode(force_unicode(s.session_data)) except (Session.DoesNotExist, SuspiciousOperation): self.create() return {} def exists(self, session_key): try: Session.objects.get(session_key=session_key) except Session.DoesNotExist: return False return True def create(self): while True: self.session_key = self._get_new_session_key() try: # Save immediately to ensure we have a unique entry in the # database. self.save(must_create=True) except CreateError: # Key wasn't unique. Try again. continue self.modified = True self._session_cache = {} return def save(self, must_create=False): """ Saves the current session data to the database. If 'must_create' is True, a database error will be raised if the saving operation doesn't create a *new* entry (as opposed to possibly updating an existing entry). """ obj = Session( session_key = self.session_key, session_data = self.encode(self._get_session(no_load=must_create)), expire_date = self.get_expiry_date() ) sid = transaction.savepoint(using=self.using) try: obj.save(force_insert=must_create) except IntegrityError: if must_create: transaction.savepoint_rollback(sid, using=self.using) raise CreateError raise def delete(self, session_key=None): if session_key is None: if self._session_key is None: return session_key = self._session_key try: Session.objects.get(session_key=session_key).delete() except Session.DoesNotExist: pass