+
−"""helper functions for application hooks
+
−
+
−: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 import RepositoryError
+
−from cubicweb.server.pool import SingleLastOperation
+
−
+
−def entity_oldnewvalue(entity, attr):
+
−    """returns the couple (old attr value, new attr value)
+
−
+
−    NOTE: will only work in a before_update_entity hook
+
−    """
+
−    # get new value and remove from local dict to force a db query to
+
−    # fetch old value
+
−    newvalue = entity.pop(attr, None)
+
−    oldvalue = getattr(entity, attr)
+
−    if newvalue is not None:
+
−        entity[attr] = newvalue
+
−    return oldvalue, newvalue
+
−
+
−def rproperty(session, rtype, eidfrom, eidto, rprop):
+
−    rschema = session.repo.schema[rtype]
+
−    subjtype = session.describe(eidfrom)[0]
+
−    objtype = session.describe(eidto)[0]
+
−    return rschema.rproperty(subjtype, objtype, rprop)
+
−
+
−def check_internal_entity(session, eid, internal_names):
+
−    """check that the entity's name is not in the internal_names list.
+
−    raise a RepositoryError if so, else return the entity's name
+
−    """
+
−    name = session.entity_from_eid(eid).name
+
−    if name in internal_names:
+
−        raise RepositoryError('%s entity can\'t be deleted' % name)
+
−    return name
+
−
+
−def get_user_sessions(repo, ueid):
+
−    for session in repo._sessions.values():
+
−        if ueid == session.user.eid:
+
−            yield session
+
−
+
−
+
−# mail related ################################################################
+
−
+
−class SendMailOp(SingleLastOperation):
+
−    def __init__(self, session, msg=None, recipients=None, **kwargs):
+
−        # may not specify msg yet, as
+
−        # `cubicweb.sobjects.supervision.SupervisionMailOp`
+
−        if msg is not None:
+
−            assert recipients
+
−            self.to_send = [(msg, recipients)]
+
−        else:
+
−            assert recipients is None
+
−            self.to_send = []
+
−        super(SendMailOp, self).__init__(session, **kwargs)
+
−
+
−    def register(self, session):
+
−        previous = super(SendMailOp, self).register(session)
+
−        if previous:
+
−            self.to_send = previous.to_send + self.to_send
+
−
+
−    def commit_event(self):
+
−        self.repo.threaded_task(self.sendmails)
+
−
+
−    def sendmails(self):
+
−        self.config.sendmails(self.to_send)
+
−
+
−
+
−# state related ###############################################################
+
−
+
−def previous_state(session, eid):
+
−    """return the state of the entity with the given eid,
+
−    usually since it's changing in the current transaction. Due to internal
+
−    relation hooks, the relation may has been deleted at this point, so
+
−    we have handle that
+
−    """
+
−    # don't check eid in session.transaction_data.get('neweids', ()), we don't
+
−    # want to miss previous state of entity whose state change in the same
+
−    # transaction as it's being created
+
−    pending = session.transaction_data.get('pendingrelations', ())
+
−    for eidfrom, rtype, eidto in reversed(pending):
+
−        if rtype == 'in_state' and eidfrom == eid:
+
−            rset = session.execute('Any S,N WHERE S eid %(x)s, S name N',
+
−                                   {'x': eidto}, 'x')
+
−            return rset.get_entity(0, 0)
+
−    rset = session.execute('Any S,N WHERE X eid %(x)s, X in_state S, S name N',
+
−                           {'x': eid}, 'x')
+
−    if rset:
+
−        return rset.get_entity(0, 0)