[source storage] refactor source sql generation and results handling to allow repository side callbacks for instance with the BytesFileSystemStorage, before this change: * fspath, _fsopen function were stored procedures executed on the database -> files had to be available both on the repository *and* the database host * we needed implementation for each handled database Now, those function are python callbacks executed when necessary on the repository side, on data comming from the database. The litle cons are: * you can't do anymore restriction on mapped attributes * you can't write queries which will return in the same rset column some mapped attributes (or not mapped the same way) / some not This seems much acceptable since: * it's much more easy to handle when you start having the db on another host than the repo * BFSS works seemlessly on any backend now * you don't bother that much about the cons (at least in the bfss case): you usually don't do any restriction on Bytes... Bonus points: BFSS is more efficient (no queries under the cover as it was done in the registered procedure) and we have a much nicer/efficient fspath implementation. IMO, that rocks :D

"""bookmark related 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.server import hook


class AutoDeleteBookmarkOp(hook.Operation):
    bookmark = None # make pylint happy
    def precommit_event(self):
        if not self.session.deleted_in_transaction(self.bookmark.eid):
            if not self.bookmark.bookmarked_by:
                self.bookmark.delete()


class DelBookmarkedByHook(hook.Hook):
    """ensure user logins are stripped"""
    __regid__ = 'autodelbookmark'
    __select__ = hook.Hook.__select__ & hook.match_rtype('bookmarked_by',)
    category = 'bookmark'
    events = ('after_delete_relation',)

    def __call__(self):
        AutoDeleteBookmarkOp(self._cw,
                             bookmark=self._cw.entity_from_eid(self.eidfrom))