+
−# copyright 2003-2012 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
+
−# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
+
−#
+
−# This file is part of CubicWeb.
+
−#
+
−# CubicWeb is free software: you can redistribute it and/or modify it under the
+
−# terms of the GNU Lesser General Public License as published by the Free
+
−# Software Foundation, either version 2.1 of the License, or (at your option)
+
−# any later version.
+
−#
+
−# CubicWeb is distributed in the hope that it will be useful, but WITHOUT
+
−# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+
−# FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
+
−# details.
+
−#
+
−# You should have received a copy of the GNU Lesser General Public License along
+
−# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.
+
−"""helper classes to handle server-side edition of entities"""
+
−__docformat__ = "restructuredtext en"
+
−
+
−from copy import copy
+
−from yams import ValidationError
+
−
+
−
+
−_MARKER = object()
+
−
+
−class dict_protocol_catcher(object):
+
−    def __init__(self, entity):
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−        self.__entity = entity
+
−    def __getitem__(self, attr):
+
−        return self.__entity.cw_edited[attr]
+
−    def __setitem__(self, attr, value):
+
−        self.__entity.cw_edited[attr] = value
+
−    def __getattr__(self, attr):
+
−        return getattr(self.__entity, attr)
+
−
+
−
+
−class EditedEntity(dict):
+
−    """encapsulate entities attributes being written by an RQL query"""
+
−    def __init__(self, entity, **kwargs):
+
−        dict.__init__(self, **kwargs)
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−        self.entity = entity
+
−        self.skip_security = set()
+
−        self.querier_pending_relations = {}
+
−        self.saved = False
+
−
+
−    def __hash__(self):
+
−        # dict|set keyable
+
−        return hash(id(self))
+
−
+
−    def __lt__(self, other):
+
−        # we don't want comparison by value inherited from dict
+
−        return id(self) < id(other)
+
−
+
−    def __eq__(self, other):
+
−        return id(self) == id(other)
+
−
+
−    def __setitem__(self, attr, value):
+
−        assert attr != 'eid'
+
−        # don't add attribute into skip_security if already in edited
+
−        # attributes, else we may accidentaly skip a desired security check
+
−        if attr not in self:
+
−            self.skip_security.add(attr)
+
−        self.edited_attribute(attr, value)
+
−
+
−    def __delitem__(self, attr):
+
−        assert not self.saved, 'too late to modify edited attributes'
+
−        super(EditedEntity, self).__delitem__(attr)
+
−        self.entity.cw_attr_cache.pop(attr, None)
+
−
+
−    def __copy__(self):
+
−        # default copy protocol fails in EditedEntity.__setitem__ because
+
−        # copied entity has no skip_security attribute at this point
+
−        return EditedEntity(self.entity, **self)
+
−
+
−    def pop(self, attr, *args):
+
−        # don't update skip_security by design (think to storage api)
+
−        assert not self.saved, 'too late to modify edited attributes'
+
−        value = super(EditedEntity, self).pop(attr, *args)
+
−        self.entity.cw_attr_cache.pop(attr, *args)
+
−        return value
+
−
+
−    def setdefault(self, attr, default):
+
−        assert attr != 'eid'
+
−        # don't add attribute into skip_security if already in edited
+
−        # attributes, else we may accidentaly skip a desired security check
+
−        if attr not in self:
+
−            self[attr] = default
+
−        return self[attr]
+
−
+
−    def update(self, values, skipsec=True):
+
−        if skipsec:
+
−            setitem = self.__setitem__
+
−        else:
+
−            setitem = self.edited_attribute
+
−        for attr, value in values.iteritems():
+
−            setitem(attr, value)
+
−
+
−    def edited_attribute(self, attr, value):
+
−        """attribute being edited by a rql query: should'nt be added to
+
−        skip_security
+
−        """
+
−        assert not self.saved, 'too late to modify edited attributes'
+
−        super(EditedEntity, self).__setitem__(attr, value)
+
−        self.entity.cw_attr_cache[attr] = value
+
−        # mark attribute as needing purge by the client
+
−        self.entity._cw_dont_cache_attribute(attr)
+
−
+
−    def oldnewvalue(self, attr):
+
−        """returns the couple (old attr value, new attr value)
+
−
+
−        NOTE: will only work in a before_update_entity hook
+
−        """
+
−        assert not self.saved, 'too late to get the old value'
+
−        # get new value and remove from local dict to force a db query to
+
−        # fetch old value
+
−        newvalue = self.entity.cw_attr_cache.pop(attr, _MARKER)
+
−        oldvalue = getattr(self.entity, attr)
+
−        if newvalue is not _MARKER:
+
−            self.entity.cw_attr_cache[attr] = newvalue
+
−        else:
+
−            newvalue = oldvalue
+
−        return oldvalue, newvalue
+
−
+
−    def set_defaults(self):
+
−        """set default values according to the schema"""
+
−        for attr, value in self.entity.e_schema.defaults():
+
−            if not attr in self:
+
−                self[str(attr)] = value
+
−
+
−    def check(self, creation=False):
+
−        """check the entity edition against its schema. Only final relation
+
−        are checked here, constraint on actual relations are checked in hooks
+
−        """
+
−        entity = self.entity
+
−        if creation:
+
−            # on creations, we want to check all relations, especially
+
−            # required attributes
+
−            relations = [rschema for rschema in entity.e_schema.subject_relations()
+
−                         if rschema.final and rschema.type != 'eid']
+
−        else:
+
−            relations = [entity._cw.vreg.schema.rschema(rtype)
+
−                         for rtype in self]
+
−        try:
+
−            entity.e_schema.check(dict_protocol_catcher(entity),
+
−                                  creation=creation, relations=relations)
+
−        except ValidationError as ex:
+
−            ex.entity = self.entity.eid
+
−            raise
+
−
+
−    def clone(self):
+
−        thecopy = EditedEntity(copy(self.entity))
+
−        thecopy.entity.cw_attr_cache = copy(self.entity.cw_attr_cache)
+
−        thecopy.entity._cw_related_cache = {}
+
−        thecopy.update(self, skipsec=False)
+
−        return thecopy