[schema migration] import refactoring to fix #1109558 and enhances things on the way
the main pb demonstrated by #1109558 was due to the fact that in-memory schema
was updated in commit_event of operations. This is undesired in most cases,
since we want the modification to be taken into account in the interval between
the modification detection and the commit_event.
I've fixed this by merging in-memory schema / database alteration operations
for most important changes, doing in-memory schema changes as they are detected
and implementing a revertcommit_event method to revert them if necessary (with
exception for removal of stuff from the schema, where this is simply done in a
postcommit_event methods).
Also, I've benefited from this to support reverting of database alteration for
some operations (more to be done there), and to move so system source alteration
code to the native source code for a nicer design.
There may be some more stuff in syncschema.py that would benefit from similar
changes, but most important things are done (at least to close #1109558, w/
unittest_syncschema and unittest_migration green).
# copyright 2003-2010 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/>.
"""undoable transaction objects.
This module is in the cubicweb package and not in cubicweb.server because those
objects should be accessible to client through pyro, where the cubicweb.server
package may not be installed.
"""
__docformat__ = "restructuredtext en"
_ = unicode
from cubicweb import RepositoryError
ACTION_LABELS = {
'C': _('entity creation'),
'U': _('entity update'),
'D': _('entity deletion'),
'A': _('relation add'),
'R': _('relation removal'),
}
class NoSuchTransaction(RepositoryError):
pass
class Transaction(object):
"""an undoable transaction"""
def __init__(self, uuid, time, ueid):
self.uuid = uuid
self.datetime = time
self.user_eid = ueid
# should be set by the dbapi connection
self.req = None
def __repr__(self):
return '<Transaction %s by %s on %s>' % (
self.uuid, self.user_eid, self.datetime)
def user(self):
"""return the user entity which has done the transaction,
none if not found.
"""
return self.req.execute('Any X WHERE X eid %(x)s',
{'x': self.user_eid}).get_entity(0, 0)
def actions_list(self, public=True):
"""return an ordered list of action effectued during that transaction
if public is true, return only 'public' action, eg not ones triggered
under the cover by hooks.
"""
return self.req.cnx.transaction_actions(self.uuid, public)
class AbstractAction(object):
def __init__(self, action, public, order):
self.action = action
self.public = public
self.order = order
@property
def label(self):
return ACTION_LABELS[self.action]
class EntityAction(AbstractAction):
def __init__(self, action, public, order, etype, eid, changes):
AbstractAction.__init__(self, action, public, order)
self.etype = etype
self.eid = eid
self.changes = changes
def __repr__(self):
return '<%s: %s %s (%s)>' % (
self.label, self.eid, self.changes,
self.public and 'dbapi' or 'hook')
class RelationAction(AbstractAction):
def __init__(self, action, public, order, rtype, eidfrom, eidto):
AbstractAction.__init__(self, action, public, order)
self.rtype = rtype
self.eid_from = eidfrom
self.eid_to = eidto
def __repr__(self):
return '<%s: %s %s %s (%s)>' % (
self.label, self.eid_from, self.rtype, self.eid_to,
self.public and 'dbapi' or 'hook')