"""schema hooks:
- synchronize the living schema object with the persistent schema
- perform physical update on the source when necessary
checking for schema consistency is done in hooks.py
:organization: Logilab
:copyright: 2001-2009 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 yams.schema import BASE_TYPES
from yams.buildobjs import EntityType, RelationType, RelationDefinition
from yams.schema2sql import eschema2sql, rschema2sql, type_from_constraints
from cubicweb import ValidationError, RepositoryError
from cubicweb.schema import META_RTYPES, VIRTUAL_RTYPES, CONSTRAINTS
from cubicweb.server import schemaserial as ss
from cubicweb.server.sqlutils import SQL_PREFIX
from cubicweb.server.pool import Operation, SingleLastOperation, PreCommitOperation
from cubicweb.server.hookhelper import (entity_attr, entity_name,
check_internal_entity)
TYPE_CONVERTER = { # XXX
'Boolean': bool,
'Int': int,
'Float': float,
'Password': str,
'String': unicode,
'Date' : unicode,
'Datetime' : unicode,
'Time' : unicode,
}
# core entity and relation types which can't be removed
CORE_ETYPES = list(BASE_TYPES) + ['CWEType', 'CWRType', 'CWUser', 'CWGroup',
'CWConstraint', 'CWAttribute', 'CWRelation']
CORE_RTYPES = ['eid', 'creation_date', 'modification_date', 'cwuri',
'login', 'upassword', 'name',
'is', 'instanceof', 'owned_by', 'created_by', 'in_group',
'relation_type', 'from_entity', 'to_entity',
'constrainted_by',
'read_permission', 'add_permission',
'delete_permission', 'updated_permission',
]
def get_constraints(session, entity):
constraints = []
for cstreid in session.transaction_data.get(entity.eid, ()):
cstrent = session.entity_from_eid(cstreid)
cstr = CONSTRAINTS[cstrent.type].deserialize(cstrent.value)
cstr.eid = cstreid
constraints.append(cstr)
return constraints
def add_inline_relation_column(session, etype, rtype):
"""add necessary column and index for an inlined relation"""
table = SQL_PREFIX + etype
column = SQL_PREFIX + rtype
try:
session.system_sql(str('ALTER TABLE %s ADD COLUMN %s integer'
% (table, column)), rollback_on_failure=False)
session.info('added column %s to table %s', column, table)
except:
# silent exception here, if this error has not been raised because the
# column already exists, index creation will fail anyway
session.exception('error while adding column %s to table %s',
table, column)
# create index before alter table which may expectingly fail during test
# (sqlite) while index creation should never fail (test for index existence
# is done by the dbhelper)
session.pool.source('system').create_index(session, table, column)
session.info('added index on %s(%s)', table, column)
session.transaction_data.setdefault('createdattrs', []).append(
'%s.%s' % (etype, rtype))
# operations for low-level database alteration ################################
class DropTable(PreCommitOperation):
"""actually remove a database from the instance's schema"""
table = None # make pylint happy
def precommit_event(self):
dropped = self.session.transaction_data.setdefault('droppedtables',
set())
if self.table in dropped:
return # already processed
dropped.add(self.table)
self.session.system_sql('DROP TABLE %s' % self.table)
self.info('dropped table %s', self.table)
class DropRelationTable(DropTable):
def __init__(self, session, rtype):
super(DropRelationTable, self).__init__(
session, table='%s_relation' % rtype)
session.transaction_data.setdefault('pendingrtypes', set()).add(rtype)
class DropColumn(PreCommitOperation):
"""actually remove the attribut's column from entity table in the system
database
"""
table = column = None # make pylint happy
def precommit_event(self):
session, table, column = self.session, self.table, self.column
# drop index if any
session.pool.source('system').drop_index(session, table, column)
try:
session.system_sql('ALTER TABLE %s DROP COLUMN %s'
% (table, column), rollback_on_failure=False)
self.info('dropped column %s from table %s', column, table)
except Exception, ex:
# not supported by sqlite for instance
self.error('error while altering table %s: %s', table, ex)
# base operations for in-memory schema synchronization ########################
class MemSchemaNotifyChanges(SingleLastOperation):
"""the update schema operation:
special operation which should be called once and after all other schema
operations. It will trigger internal structures rebuilding to consider
schema changes
"""
def __init__(self, session):
self.repo = session.repo
SingleLastOperation.__init__(self, session)
def commit_event(self):
self.repo.set_schema(self.repo.schema)
class MemSchemaOperation(Operation):
"""base class for schema operations"""
def __init__(self, session, kobj=None, **kwargs):
self.schema = session.schema
self.kobj = kobj
# once Operation.__init__ has been called, event may be triggered, so
# do this last !
Operation.__init__(self, session, **kwargs)
# every schema operation is triggering a schema update
MemSchemaNotifyChanges(session)
def prepare_constraints(self, subjtype, rtype, objtype):
constraints = rtype.rproperty(subjtype, objtype, 'constraints')
self.constraints = list(constraints)
rtype.set_rproperty(subjtype, objtype, 'constraints', self.constraints)
class MemSchemaEarlyOperation(MemSchemaOperation):
def insert_index(self):
"""schema operation which are inserted at the begining of the queue
(typically to add/remove entity or relation types)
"""
i = -1
for i, op in enumerate(self.session.pending_operations):
if not isinstance(op, MemSchemaEarlyOperation):
return i
return i + 1
class MemSchemaPermissionOperation(MemSchemaOperation):
"""base class to synchronize schema permission definitions"""
def __init__(self, session, perm, etype_eid):
self.perm = perm
try:
self.name = entity_name(session, etype_eid)
except IndexError:
self.error('changing permission of a no more existant type #%s',
etype_eid)
else:
Operation.__init__(self, session)
# operations for high-level source database alteration ########################
class SourceDbCWETypeRename(PreCommitOperation):
"""this operation updates physical storage accordingly"""
oldname = newname = None # make pylint happy
def precommit_event(self):
# we need sql to operate physical changes on the system database
sqlexec = self.session.system_sql
sqlexec('ALTER TABLE %s%s RENAME TO %s%s' % (SQL_PREFIX, self.oldname,
SQL_PREFIX, self.newname))
self.info('renamed table %s to %s', self.oldname, self.newname)
sqlexec('UPDATE entities SET type=%s WHERE type=%s',
(self.newname, self.oldname))
sqlexec('UPDATE deleted_entities SET type=%s WHERE type=%s',
(self.newname, self.oldname))
class SourceDbCWRTypeUpdate(PreCommitOperation):
"""actually update some properties of a relation definition"""
rschema = values = entity = None # make pylint happy
def precommit_event(self):
session = self.session
rschema = self.rschema
if rschema.is_final() or not 'inlined' in self.values:
return # nothing to do
inlined = self.values['inlined']
entity = self.entity
# check in-lining is necessary / possible
if not entity.inlined_changed(inlined):
return # nothing to do
# inlined changed, make necessary physical changes!
sqlexec = self.session.system_sql
rtype = rschema.type
eidcolumn = SQL_PREFIX + 'eid'
if not inlined:
# need to create the relation if it has not been already done by
# another event of the same transaction
if not rschema.type in session.transaction_data.get('createdtables', ()):
tablesql = rschema2sql(rschema)
# create the necessary table
for sql in tablesql.split(';'):
if sql.strip():
sqlexec(sql)
session.transaction_data.setdefault('createdtables', []).append(
rschema.type)
# copy existant data
column = SQL_PREFIX + rtype
for etype in rschema.subjects():
table = SQL_PREFIX + str(etype)
sqlexec('INSERT INTO %s_relation SELECT %s, %s FROM %s WHERE NOT %s IS NULL'
% (rtype, eidcolumn, column, table, column))
# drop existant columns
for etype in rschema.subjects():
DropColumn(session, table=SQL_PREFIX + str(etype),
column=SQL_PREFIX + rtype)
else:
for etype in rschema.subjects():
try:
add_inline_relation_column(session, str(etype), rtype)
except Exception, ex:
# the column probably already exists. this occurs when the
# entity's type has just been added or if the column has not
# been previously dropped
self.error('error while altering table %s: %s', etype, ex)
# copy existant data.
# XXX don't use, it's not supported by sqlite (at least at when i tried it)
#sqlexec('UPDATE %(etype)s SET %(rtype)s=eid_to '
# 'FROM %(rtype)s_relation '
# 'WHERE %(etype)s.eid=%(rtype)s_relation.eid_from'
# % locals())
table = SQL_PREFIX + str(etype)
cursor = sqlexec('SELECT eid_from, eid_to FROM %(table)s, '
'%(rtype)s_relation WHERE %(table)s.%(eidcolumn)s='
'%(rtype)s_relation.eid_from' % locals())
args = [{'val': eid_to, 'x': eid} for eid, eid_to in cursor.fetchall()]
if args:
column = SQL_PREFIX + rtype
cursor.executemany('UPDATE %s SET %s=%%(val)s WHERE %s=%%(x)s'
% (table, column, eidcolumn), args)
# drop existant table
DropRelationTable(session, rtype)
class SourceDbCWAttributeAdd(PreCommitOperation):
"""an attribute relation (CWAttribute) has been added:
* add the necessary column
* set default on this column if any and possible
* register an operation to add the relation definition to the
instance's schema on commit
constraints are handled by specific hooks
"""
entity = None # make pylint happy
def init_rdef(self, **kwargs):
entity = self.entity
fromentity = entity.stype
self.session.execute('SET X ordernum Y+1 '
'WHERE X from_entity SE, SE eid %(se)s, X ordernum Y, '
'X ordernum >= %(order)s, NOT X eid %(x)s',
{'x': entity.eid, 'se': fromentity.eid,
'order': entity.ordernum or 0})
subj = str(fromentity.name)
rtype = entity.rtype.name
obj = str(entity.otype.name)
constraints = get_constraints(self.session, entity)
rdef = RelationDefinition(subj, rtype, obj,
description=entity.description,
cardinality=entity.cardinality,
constraints=constraints,
order=entity.ordernum,
eid=entity.eid,
**kwargs)
MemSchemaRDefAdd(self.session, rdef)
return rdef
def precommit_event(self):
session = self.session
entity = self.entity
# entity.defaultval is a string or None, but we need a correctly typed
# value
default = entity.defaultval
if default is not None:
default = TYPE_CONVERTER[entity.otype.name](default)
rdef = self.init_rdef(default=default,
indexed=entity.indexed,
fulltextindexed=entity.fulltextindexed,
internationalizable=entity.internationalizable)
sysource = session.pool.source('system')
attrtype = type_from_constraints(sysource.dbhelper, rdef.object,
rdef.constraints)
# XXX should be moved somehow into lgc.adbh: sqlite doesn't support to
# add a new column with UNIQUE, it should be added after the ALTER TABLE
# using ADD INDEX
if sysource.dbdriver == 'sqlite' and 'UNIQUE' in attrtype:
extra_unique_index = True
attrtype = attrtype.replace(' UNIQUE', '')
else:
extra_unique_index = False
# added some str() wrapping query since some backend (eg psycopg) don't
# allow unicode queries
table = SQL_PREFIX + rdef.subject
column = SQL_PREFIX + rdef.name
try:
session.system_sql(str('ALTER TABLE %s ADD COLUMN %s %s'
% (table, column, attrtype)),
rollback_on_failure=False)
self.info('added column %s to table %s', table, column)
except Exception, ex:
# the column probably already exists. this occurs when
# the entity's type has just been added or if the column
# has not been previously dropped
self.error('error while altering table %s: %s', table, ex)
if extra_unique_index or entity.indexed:
try:
sysource.create_index(session, table, column,
unique=extra_unique_index)
except Exception, ex:
self.error('error while creating index for %s.%s: %s',
table, column, ex)
class SourceDbCWRelationAdd(SourceDbCWAttributeAdd):
"""an actual relation has been added:
* if this is an inlined relation, add the necessary column
else if it's the first instance of this relation type, add the
necessary table and set default permissions
* register an operation to add the relation definition to the
instance's schema on commit
constraints are handled by specific hooks
"""
entity = None # make pylint happy
def precommit_event(self):
session = self.session
entity = self.entity
rdef = self.init_rdef(composite=entity.composite)
schema = session.schema
rtype = rdef.name
rschema = session.schema.rschema(rtype)
# this have to be done before permissions setting
if rschema.inlined:
# need to add a column if the relation is inlined and if this is the
# first occurence of "Subject relation Something" whatever Something
# and if it has not been added during other event of the same
# transaction
key = '%s.%s' % (rdef.subject, rtype)
try:
alreadythere = bool(rschema.objects(rdef.subject))
except KeyError:
alreadythere = False
if not (alreadythere or
key in session.transaction_data.get('createdattrs', ())):
add_inline_relation_column(session, rdef.subject, rtype)
else:
# need to create the relation if no relation definition in the
# schema and if it has not been added during other event of the same
# transaction
if not (rschema.subjects() or
rtype in session.transaction_data.get('createdtables', ())):
try:
rschema = session.schema.rschema(rtype)
tablesql = rschema2sql(rschema)
except KeyError:
# fake we add it to the schema now to get a correctly
# initialized schema but remove it before doing anything
# more dangerous...
rschema = session.schema.add_relation_type(rdef)
tablesql = rschema2sql(rschema)
session.schema.del_relation_type(rtype)
# create the necessary table
for sql in tablesql.split(';'):
if sql.strip():
session.system_sql(sql)
session.transaction_data.setdefault('createdtables', []).append(
rtype)
class SourceDbRDefUpdate(PreCommitOperation):
"""actually update some properties of a relation definition"""
rschema = values = None # make pylint happy
def precommit_event(self):
etype = self.kobj[0]
table = SQL_PREFIX + etype
column = SQL_PREFIX + self.rschema.type
if 'indexed' in self.values:
sysource = self.session.pool.source('system')
if self.values['indexed']:
sysource.create_index(self.session, table, column)
else:
sysource.drop_index(self.session, table, column)
if 'cardinality' in self.values and self.rschema.is_final():
adbh = self.session.pool.source('system').dbhelper
if not adbh.alter_column_support:
# not supported (and NOT NULL not set by yams in that case, so
# no worry)
return
atype = self.rschema.objects(etype)[0]
constraints = self.rschema.rproperty(etype, atype, 'constraints')
coltype = type_from_constraints(adbh, atype, constraints,
creating=False)
# XXX check self.values['cardinality'][0] actually changed?
sql = adbh.sql_set_null_allowed(table, column, coltype,
self.values['cardinality'][0] != '1')
self.session.system_sql(sql)
class SourceDbCWConstraintAdd(PreCommitOperation):
"""actually update constraint of a relation definition"""
entity = None # make pylint happy
cancelled = False
def precommit_event(self):
rdef = self.entity.reverse_constrained_by[0]
session = self.session
# when the relation is added in the same transaction, the constraint
# object is created by the operation adding the attribute or relation,
# so there is nothing to do here
if rdef.eid in session.transaction_data.get('neweids', ()):
return
subjtype, rtype, objtype = session.schema.schema_by_eid(rdef.eid)
cstrtype = self.entity.type
oldcstr = rtype.constraint_by_type(subjtype, objtype, cstrtype)
newcstr = CONSTRAINTS[cstrtype].deserialize(self.entity.value)
table = SQL_PREFIX + str(subjtype)
column = SQL_PREFIX + str(rtype)
# alter the physical schema on size constraint changes
if newcstr.type() == 'SizeConstraint' and (
oldcstr is None or oldcstr.max != newcstr.max):
adbh = self.session.pool.source('system').dbhelper
card = rtype.rproperty(subjtype, objtype, 'cardinality')
coltype = type_from_constraints(adbh, objtype, [newcstr],
creating=False)
sql = adbh.sql_change_col_type(table, column, coltype, card != '1')
try:
session.system_sql(sql, rollback_on_failure=False)
self.info('altered column %s of table %s: now VARCHAR(%s)',
column, table, newcstr.max)
except Exception, ex:
# not supported by sqlite for instance
self.error('error while altering table %s: %s', table, ex)
elif cstrtype == 'UniqueConstraint' and oldcstr is None:
session.pool.source('system').create_index(
self.session, table, column, unique=True)
class SourceDbCWConstraintDel(PreCommitOperation):
"""actually remove a constraint of a relation definition"""
rtype = subjtype = objtype = None # make pylint happy
def precommit_event(self):
cstrtype = self.cstr.type()
table = SQL_PREFIX + str(self.subjtype)
column = SQL_PREFIX + str(self.rtype)
# alter the physical schema on size/unique constraint changes
if cstrtype == 'SizeConstraint':
try:
self.session.system_sql('ALTER TABLE %s ALTER COLUMN %s TYPE TEXT'
% (table, column),
rollback_on_failure=False)
self.info('altered column %s of table %s: now TEXT',
column, table)
except Exception, ex:
# not supported by sqlite for instance
self.error('error while altering table %s: %s', table, ex)
elif cstrtype == 'UniqueConstraint':
self.session.pool.source('system').drop_index(
self.session, table, column, unique=True)
# operations for in-memory schema synchronization #############################
class MemSchemaCWETypeAdd(MemSchemaEarlyOperation):
"""actually add the entity type to the instance's schema"""
eid = None # make pylint happy
def commit_event(self):
self.schema.add_entity_type(self.kobj)
class MemSchemaCWETypeRename(MemSchemaOperation):
"""this operation updates physical storage accordingly"""
oldname = newname = None # make pylint happy
def commit_event(self):
self.session.schema.rename_entity_type(self.oldname, self.newname)
class MemSchemaCWETypeDel(MemSchemaOperation):
"""actually remove the entity type from the instance's schema"""
def commit_event(self):
try:
# del_entity_type also removes entity's relations
self.schema.del_entity_type(self.kobj)
except KeyError:
# s/o entity type have already been deleted
pass
class MemSchemaCWRTypeAdd(MemSchemaEarlyOperation):
"""actually add the relation type to the instance's schema"""
eid = None # make pylint happy
def commit_event(self):
rschema = self.schema.add_relation_type(self.kobj)
rschema.set_default_groups()
class MemSchemaCWRTypeUpdate(MemSchemaOperation):
"""actually update some properties of a relation definition"""
rschema = values = None # make pylint happy
def commit_event(self):
# structure should be clean, not need to remove entity's relations
# at this point
self.rschema.__dict__.update(self.values)
class MemSchemaCWRTypeDel(MemSchemaOperation):
"""actually remove the relation type from the instance's schema"""
def commit_event(self):
try:
self.schema.del_relation_type(self.kobj)
except KeyError:
# s/o entity type have already been deleted
pass
class MemSchemaRDefAdd(MemSchemaEarlyOperation):
"""actually add the attribute relation definition to the instance's
schema
"""
def commit_event(self):
self.schema.add_relation_def(self.kobj)
class MemSchemaRDefUpdate(MemSchemaOperation):
"""actually update some properties of a relation definition"""
rschema = values = None # make pylint happy
def commit_event(self):
# structure should be clean, not need to remove entity's relations
# at this point
self.rschema._rproperties[self.kobj].update(self.values)
class MemSchemaRDefDel(MemSchemaOperation):
"""actually remove the relation definition from the instance's schema"""
def commit_event(self):
subjtype, rtype, objtype = self.kobj
try:
self.schema.del_relation_def(subjtype, rtype, objtype)
except KeyError:
# relation type may have been already deleted
pass
class MemSchemaCWConstraintAdd(MemSchemaOperation):
"""actually update constraint of a relation definition
has to be called before SourceDbCWConstraintAdd
"""
cancelled = False
def precommit_event(self):
rdef = self.entity.reverse_constrained_by[0]
# when the relation is added in the same transaction, the constraint
# object is created by the operation adding the attribute or relation,
# so there is nothing to do here
if rdef.eid in self.session.transaction_data.get('neweids', ()):
self.cancelled = True
return
subjtype, rtype, objtype = self.session.schema.schema_by_eid(rdef.eid)
self.prepare_constraints(subjtype, rtype, objtype)
cstrtype = self.entity.type
self.cstr = rtype.constraint_by_type(subjtype, objtype, cstrtype)
self.newcstr = CONSTRAINTS[cstrtype].deserialize(self.entity.value)
self.newcstr.eid = self.entity.eid
def commit_event(self):
if self.cancelled:
return
# in-place modification
if not self.cstr is None:
self.constraints.remove(self.cstr)
self.constraints.append(self.newcstr)
class MemSchemaCWConstraintDel(MemSchemaOperation):
"""actually remove a constraint of a relation definition
has to be called before SourceDbCWConstraintDel
"""
rtype = subjtype = objtype = None # make pylint happy
def precommit_event(self):
self.prepare_constraints(self.subjtype, self.rtype, self.objtype)
def commit_event(self):
self.constraints.remove(self.cstr)
class MemSchemaPermissionCWGroupAdd(MemSchemaPermissionOperation):
"""synchronize schema when a *_permission relation has been added on a group
"""
def __init__(self, session, perm, etype_eid, group_eid):
self.group = entity_name(session, group_eid)
super(MemSchemaPermissionCWGroupAdd, self).__init__(
session, perm, etype_eid)
def commit_event(self):
"""the observed connections pool has been commited"""
try:
erschema = self.schema[self.name]
except KeyError:
# duh, schema not found, log error and skip operation
self.error('no schema for %s', self.name)
return
groups = list(erschema.get_groups(self.perm))
try:
groups.index(self.group)
self.warning('group %s already have permission %s on %s',
self.group, self.perm, erschema.type)
except ValueError:
groups.append(self.group)
erschema.set_groups(self.perm, groups)
class MemSchemaPermissionCWGroupDel(MemSchemaPermissionCWGroupAdd):
"""synchronize schema when a *_permission relation has been deleted from a
group
"""
def commit_event(self):
"""the observed connections pool has been commited"""
try:
erschema = self.schema[self.name]
except KeyError:
# duh, schema not found, log error and skip operation
self.error('no schema for %s', self.name)
return
groups = list(erschema.get_groups(self.perm))
try:
groups.remove(self.group)
erschema.set_groups(self.perm, groups)
except ValueError:
self.error('can\'t remove permission %s on %s to group %s',
self.perm, erschema.type, self.group)
class MemSchemaPermissionRQLExpressionAdd(MemSchemaPermissionOperation):
"""synchronize schema when a *_permission relation has been added on a rql
expression
"""
def __init__(self, session, perm, etype_eid, expression):
self.expr = expression
super(MemSchemaPermissionRQLExpressionAdd, self).__init__(
session, perm, etype_eid)
def commit_event(self):
"""the observed connections pool has been commited"""
try:
erschema = self.schema[self.name]
except KeyError:
# duh, schema not found, log error and skip operation
self.error('no schema for %s', self.name)
return
exprs = list(erschema.get_rqlexprs(self.perm))
exprs.append(erschema.rql_expression(self.expr))
erschema.set_rqlexprs(self.perm, exprs)
class MemSchemaPermissionRQLExpressionDel(MemSchemaPermissionRQLExpressionAdd):
"""synchronize schema when a *_permission relation has been deleted from an
rql expression
"""
def commit_event(self):
"""the observed connections pool has been commited"""
try:
erschema = self.schema[self.name]
except KeyError:
# duh, schema not found, log error and skip operation
self.error('no schema for %s', self.name)
return
rqlexprs = list(erschema.get_rqlexprs(self.perm))
for i, rqlexpr in enumerate(rqlexprs):
if rqlexpr.expression == self.expr:
rqlexprs.pop(i)
break
else:
self.error('can\'t remove permission %s on %s for expression %s',
self.perm, erschema.type, self.expr)
return
erschema.set_rqlexprs(self.perm, rqlexprs)
# deletion hooks ###############################################################
def before_del_eetype(session, eid):
"""before deleting a CWEType entity:
* check that we don't remove a core entity type
* cascade to delete related CWAttribute and CWRelation entities
* instantiate an operation to delete the entity type on commit
"""
# final entities can't be deleted, don't care about that
name = check_internal_entity(session, eid, CORE_ETYPES)
# delete every entities of this type
session.unsafe_execute('DELETE %s X' % name)
DropTable(session, table=SQL_PREFIX + name)
MemSchemaCWETypeDel(session, name)
def after_del_eetype(session, eid):
# workflow cleanup
session.execute('DELETE State X WHERE NOT X state_of Y')
session.execute('DELETE Transition X WHERE NOT X transition_of Y')
def before_del_ertype(session, eid):
"""before deleting a CWRType entity:
* check that we don't remove a core relation type
* cascade to delete related CWAttribute and CWRelation entities
* instantiate an operation to delete the relation type on commit
"""
name = check_internal_entity(session, eid, CORE_RTYPES)
# delete relation definitions using this relation type
session.execute('DELETE CWAttribute X WHERE X relation_type Y, Y eid %(x)s',
{'x': eid})
session.execute('DELETE CWRelation X WHERE X relation_type Y, Y eid %(x)s',
{'x': eid})
MemSchemaCWRTypeDel(session, name)
def after_del_relation_type(session, rdefeid, rtype, rteid):
"""before deleting a CWAttribute or CWRelation entity:
* if this is a final or inlined relation definition, instantiate an
operation to drop necessary column, else if this is the last instance
of a non final relation, instantiate an operation to drop necessary
table
* instantiate an operation to delete the relation definition on commit
* delete the associated relation type when necessary
"""
subjschema, rschema, objschema = session.schema.schema_by_eid(rdefeid)
pendings = session.transaction_data.get('pendingeids', ())
# first delete existing relation if necessary
if rschema.is_final():
rdeftype = 'CWAttribute'
else:
rdeftype = 'CWRelation'
if not (subjschema.eid in pendings or objschema.eid in pendings):
pending = session.transaction_data.setdefault('pendingrdefs', set())
pending.add((subjschema, rschema, objschema))
session.execute('DELETE X %s Y WHERE X is %s, Y is %s'
% (rschema, subjschema, objschema))
execute = session.unsafe_execute
rset = execute('Any COUNT(X) WHERE X is %s, X relation_type R,'
'R eid %%(x)s' % rdeftype, {'x': rteid})
lastrel = rset[0][0] == 0
# we have to update physical schema systematically for final and inlined
# relations, but only if it's the last instance for this relation type
# for other relations
if (rschema.is_final() or rschema.inlined):
rset = execute('Any COUNT(X) WHERE X is %s, X relation_type R, '
'R eid %%(x)s, X from_entity E, E name %%(name)s'
% rdeftype, {'x': rteid, 'name': str(subjschema)})
if rset[0][0] == 0 and not subjschema.eid in pendings:
ptypes = session.transaction_data.setdefault('pendingrtypes', set())
ptypes.add(rschema.type)
DropColumn(session, table=SQL_PREFIX + subjschema.type,
column=SQL_PREFIX + rschema.type)
elif lastrel:
DropRelationTable(session, rschema.type)
# if this is the last instance, drop associated relation type
if lastrel and not rteid in pendings:
execute('DELETE CWRType X WHERE X eid %(x)s', {'x': rteid}, 'x')
MemSchemaRDefDel(session, (subjschema, rschema, objschema))
# addition hooks ###############################################################
def before_add_eetype(session, entity):
"""before adding a CWEType entity:
* check that we are not using an existing entity type,
"""
name = entity['name']
schema = session.schema
if name in schema and schema[name].eid is not None:
raise RepositoryError('an entity type %s already exists' % name)
def after_add_eetype(session, entity):
"""after adding a CWEType entity:
* create the necessary table
* set creation_date and modification_date by creating the necessary
CWAttribute entities
* add owned_by relation by creating the necessary CWRelation entity
* register an operation to add the entity type to the instance's
schema on commit
"""
if entity.get('final'):
return
schema = session.schema
name = entity['name']
etype = EntityType(name=name, description=entity.get('description'),
meta=entity.get('meta')) # don't care about final
# fake we add it to the schema now to get a correctly initialized schema
# but remove it before doing anything more dangerous...
schema = session.schema
eschema = schema.add_entity_type(etype)
eschema.set_default_groups()
# generate table sql and rql to add metadata
tablesql = eschema2sql(session.pool.source('system').dbhelper, eschema,
prefix=SQL_PREFIX)
relrqls = []
for rtype in (META_RTYPES - VIRTUAL_RTYPES):
rschema = schema[rtype]
sampletype = rschema.subjects()[0]
desttype = rschema.objects()[0]
props = rschema.rproperties(sampletype, desttype)
relrqls += list(ss.rdef2rql(rschema, name, desttype, props))
# now remove it !
schema.del_entity_type(name)
# create the necessary table
for sql in tablesql.split(';'):
if sql.strip():
session.system_sql(sql)
# register operation to modify the schema on commit
# this have to be done before adding other relations definitions
# or permission settings
etype.eid = entity.eid
MemSchemaCWETypeAdd(session, etype)
# add meta relations
for rql, kwargs in relrqls:
session.execute(rql, kwargs)
def before_add_ertype(session, entity):
"""before adding a CWRType entity:
* check that we are not using an existing relation type,
* register an operation to add the relation type to the instance's
schema on commit
We don't know yeat this point if a table is necessary
"""
name = entity['name']
if name in session.schema.relations():
raise RepositoryError('a relation type %s already exists' % name)
def after_add_ertype(session, entity):
"""after a CWRType entity has been added:
* register an operation to add the relation type to the instance's
schema on commit
We don't know yeat this point if a table is necessary
"""
rtype = RelationType(name=entity['name'],
description=entity.get('description'),
meta=entity.get('meta', False),
inlined=entity.get('inlined', False),
symetric=entity.get('symetric', False))
rtype.eid = entity.eid
MemSchemaCWRTypeAdd(session, rtype)
def after_add_efrdef(session, entity):
SourceDbCWAttributeAdd(session, entity=entity)
def after_add_enfrdef(session, entity):
SourceDbCWRelationAdd(session, entity=entity)
# update hooks #################################################################
def check_valid_changes(session, entity, ro_attrs=('name', 'final')):
errors = {}
# don't use getattr(entity, attr), we would get the modified value if any
for attr in ro_attrs:
origval = entity_attr(session, entity.eid, attr)
if entity.get(attr, origval) != origval:
errors[attr] = session._("can't change the %s attribute") % \
display_name(session, attr)
if errors:
raise ValidationError(entity.eid, errors)
def before_update_eetype(session, entity):
"""check name change, handle final"""
check_valid_changes(session, entity, ro_attrs=('final',))
# don't use getattr(entity, attr), we would get the modified value if any
oldname = entity_attr(session, entity.eid, 'name')
newname = entity.get('name', oldname)
if newname.lower() != oldname.lower():
SourceDbCWETypeRename(session, oldname=oldname, newname=newname)
MemSchemaCWETypeRename(session, oldname=oldname, newname=newname)
def before_update_ertype(session, entity):
"""check name change, handle final"""
check_valid_changes(session, entity)
def after_update_erdef(session, entity):
if entity.eid in session.transaction_data.get('pendingeids', ()):
return
desttype = entity.otype.name
rschema = session.schema[entity.rtype.name]
newvalues = {}
for prop in rschema.rproperty_defs(desttype):
if prop == 'constraints':
continue
if prop == 'order':
prop = 'ordernum'
if prop in entity.edited_attributes:
newvalues[prop] = entity[prop]
if newvalues:
subjtype = entity.stype.name
MemSchemaRDefUpdate(session, kobj=(subjtype, desttype),
rschema=rschema, values=newvalues)
SourceDbRDefUpdate(session, kobj=(subjtype, desttype),
rschema=rschema, values=newvalues)
def after_update_ertype(session, entity):
rschema = session.schema.rschema(entity.name)
newvalues = {}
for prop in ('meta', 'symetric', 'inlined'):
if prop in entity:
newvalues[prop] = entity[prop]
if newvalues:
MemSchemaCWRTypeUpdate(session, rschema=rschema, values=newvalues)
SourceDbCWRTypeUpdate(session, rschema=rschema, values=newvalues,
entity=entity)
# constraints synchronization hooks ############################################
def after_add_econstraint(session, entity):
MemSchemaCWConstraintAdd(session, entity=entity)
SourceDbCWConstraintAdd(session, entity=entity)
def after_update_econstraint(session, entity):
MemSchemaCWConstraintAdd(session, entity=entity)
SourceDbCWConstraintAdd(session, entity=entity)
def before_delete_constrained_by(session, fromeid, rtype, toeid):
if not fromeid in session.transaction_data.get('pendingeids', ()):
schema = session.schema
entity = session.entity_from_eid(toeid)
subjtype, rtype, objtype = schema.schema_by_eid(fromeid)
try:
cstr = rtype.constraint_by_type(subjtype, objtype,
entity.cstrtype[0].name)
except IndexError:
session.critical('constraint type no more accessible')
else:
SourceDbCWConstraintDel(session, subjtype=subjtype, rtype=rtype,
objtype=objtype, cstr=cstr)
MemSchemaCWConstraintDel(session, subjtype=subjtype, rtype=rtype,
objtype=objtype, cstr=cstr)
def after_add_constrained_by(session, fromeid, rtype, toeid):
if fromeid in session.transaction_data.get('neweids', ()):
session.transaction_data.setdefault(fromeid, []).append(toeid)
# permissions synchronization hooks ############################################
def after_add_permission(session, subject, rtype, object):
"""added entity/relation *_permission, need to update schema"""
perm = rtype.split('_', 1)[0]
if session.describe(object)[0] == 'CWGroup':
MemSchemaPermissionCWGroupAdd(session, perm, subject, object)
else: # RQLExpression
expr = session.execute('Any EXPR WHERE X eid %(x)s, X expression EXPR',
{'x': object}, 'x')[0][0]
MemSchemaPermissionRQLExpressionAdd(session, perm, subject, expr)
def before_del_permission(session, subject, rtype, object):
"""delete entity/relation *_permission, need to update schema
skip the operation if the related type is being deleted
"""
if subject in session.transaction_data.get('pendingeids', ()):
return
perm = rtype.split('_', 1)[0]
if session.describe(object)[0] == 'CWGroup':
MemSchemaPermissionCWGroupDel(session, perm, subject, object)
else: # RQLExpression
expr = session.execute('Any EXPR WHERE X eid %(x)s, X expression EXPR',
{'x': object}, 'x')[0][0]
MemSchemaPermissionRQLExpressionDel(session, perm, subject, expr)
def rebuild_infered_relations(session, subject, rtype, object):
# registering a schema operation will trigger a call to
# repo.set_schema() on commit which will in turn rebuild
# infered relation definitions
MemSchemaNotifyChanges(session)
def _register_schema_hooks(hm):
"""register schema related hooks on the hooks manager"""
# schema synchronisation #####################
# before/after add
hm.register_hook(before_add_eetype, 'before_add_entity', 'CWEType')
hm.register_hook(before_add_ertype, 'before_add_entity', 'CWRType')
hm.register_hook(after_add_eetype, 'after_add_entity', 'CWEType')
hm.register_hook(after_add_ertype, 'after_add_entity', 'CWRType')
hm.register_hook(after_add_efrdef, 'after_add_entity', 'CWAttribute')
hm.register_hook(after_add_enfrdef, 'after_add_entity', 'CWRelation')
# before/after update
hm.register_hook(before_update_eetype, 'before_update_entity', 'CWEType')
hm.register_hook(before_update_ertype, 'before_update_entity', 'CWRType')
hm.register_hook(after_update_ertype, 'after_update_entity', 'CWRType')
hm.register_hook(after_update_erdef, 'after_update_entity', 'CWAttribute')
hm.register_hook(after_update_erdef, 'after_update_entity', 'CWRelation')
# before/after delete
hm.register_hook(before_del_eetype, 'before_delete_entity', 'CWEType')
hm.register_hook(after_del_eetype, 'after_delete_entity', 'CWEType')
hm.register_hook(before_del_ertype, 'before_delete_entity', 'CWRType')
hm.register_hook(after_del_relation_type, 'after_delete_relation', 'relation_type')
hm.register_hook(rebuild_infered_relations, 'after_add_relation', 'specializes')
hm.register_hook(rebuild_infered_relations, 'after_delete_relation', 'specializes')
# constraints synchronization hooks
hm.register_hook(after_add_econstraint, 'after_add_entity', 'CWConstraint')
hm.register_hook(after_update_econstraint, 'after_update_entity', 'CWConstraint')
hm.register_hook(before_delete_constrained_by, 'before_delete_relation', 'constrained_by')
hm.register_hook(after_add_constrained_by, 'after_add_relation', 'constrained_by')
# permissions synchronisation ################
for perm in ('read_permission', 'add_permission',
'delete_permission', 'update_permission'):
hm.register_hook(after_add_permission, 'after_add_relation', perm)
hm.register_hook(before_del_permission, 'before_delete_relation', perm)