--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/cubicweb/server/edition.py Sat Jan 16 13:48:51 2016 +0100
@@ -0,0 +1,159 @@
+# 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):
+ 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):
+ super(EditedEntity, self).__init__(**kwargs)
+ 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
+ raise NotImplementedError
+
+ def __eq__(self, other):
+ return self is other
+
+ def __ne__(self, other):
+ return not (self == other)
+
+ def __setitem__(self, attr, value):
+ assert attr != 'eid'
+ # don't add attribute into skip_security if already in edited
+ # attributes, else we may accidentally 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 accidentally 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.items():
+ 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
+ if self.entity._cw.vreg.schema.rschema(attr).final:
+ 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