# copyright 2014 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 functions for migrations that aren't reliable enough or too dangerous
to be available in the standard migration environment
"""
def drop_entity_types_fast(*etypes, **kwargs):
"""drop an entity type bypassing all hooks
here be dragons.
"""
# XXX cascade deletion through composite relations?
for etype in etypes:
if etype not in schema:
print('%s does not exist' % etype)
continue
etype = schema[etype]
# ignore attributes and inlined rels since they'll be dropped anyway
srels = [x.type for x in etype.subject_relations() if x.eid and not (x.final or x.inlined)]
orels = [x.type for x in etype.object_relations() if x.eid and not x.inlined]
inlined_rels = [x for x in etype.object_relations() if x.eid and x.inlined]
# eids to be deleted could be listed in some other entity tables through inlined relations
for rtype in inlined_rels:
for subjtype in rtype.subjects(etype):
if subjtype in etypes:
continue
sql('UPDATE cw_%(stype)s SET cw_%(rtype)s = NULL '
'WHERE cw_%(rtype)s IN (SELECT eid FROM entities WHERE type = %%s)' %
{'stype': subjtype.type, 'rtype': rtype.type},
(etype.type,))
for rel in srels:
if all(subj in etypes for subj in rel.subjects()) or all(obj in etypes for obj in rel.objects()):
sql('DELETE FROM %s_relation' % rel.type)
else:
sql('DELETE FROM %s_relation WHERE eid_from IN (SELECT eid FROM entities WHERE type = %%s)' % rel.type, (etype.type,))
for rel in orels:
if all(subj in etypes for subj in rel.subjects()) or all(obj in etypes for obj in rel.objects()):
sql('DELETE FROM %s_relation' % rel.type)
else:
sql('DELETE FROM %s_relation WHERE eid_to IN (SELECT eid FROM entities WHERE type = %%s)' % rel, (etype.type,))
sql('DELETE FROM appears WHERE uid IN (SELECT eid FROM entities WHERE type = %s)', (etype.type,))
sql('DELETE FROM cw_%s' % etype.type)
sql('DELETE FROM entities WHERE type = %s', (etype.type,))
for etype in etypes:
drop_entity_type(etype, **kwargs)