"""web session component: by dfault the session is actually the db connection

object :/

:organization: Logilab

:copyright: 2001-2010 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.

:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr

:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses

"""

__docformat__ = "restructuredtext en"

from cubicweb.web import InvalidSession

from cubicweb.web.application import AbstractSessionManager

from cubicweb.dbapi import DBAPISession

class InMemoryRepositorySessionManager(AbstractSessionManager):

    """manage session data associated to a session identifier"""

    def __init__(self, *args, **kwargs):

        AbstractSessionManager.__init__(self, *args, **kwargs)

        # XXX require a RepositoryAuthenticationManager which violates

        #     authenticate interface by returning a session instead of a user

        #assert isinstance(self.authmanager, RepositoryAuthenticationManager)

        self._sessions = {}

    # dump_data / restore_data to avoid loosing open sessions on registry

    # reloading

    def dump_data(self):

        return self._sessions

    def restore_data(self, data):

        self._sessions = data

    def current_sessions(self):

        return self._sessions.values()

    def get_session(self, req, sessionid):

        """return existing session for the given session identifier"""

        if not sessionid in self._sessions:

            raise InvalidSession()

        session = self._sessions[sessionid]

        if self.has_expired(session):

            self.close_session(session)

            raise InvalidSession()

        try:

            user = self.authmanager.validate_session(req, session)

        except InvalidSession:

            # invalid session

            self.close_session(session)

            raise

        # associate the connection to the current request

        req.set_session(session, user)

        return session

    def open_session(self, req):

        """open and return a new session for the given request. The session is

        also bound to the request.

        raise :exc:`cubicweb.AuthenticationError` if authentication failed

        (no authentication info found or wrong user/password)

        """

        cnx, login, authinfo = self.authmanager.authenticate(req)

        session = DBAPISession(cnx, login, authinfo)

        self._sessions[session.sessionid] = session

        # associate the connection to the current request

        req.set_session(session)

        return session

    def close_session(self, session):

        """close session on logout or on invalid session detected (expired out,

        corrupted...)

        """

        self.info('closing http session %s' % session)

        del self._sessions[session.sessionid]

        try:

            session.cnx.close()

        except:

            # already closed, may occurs if the repository session expired but

            # not the web session

            pass

        session.cnx = None