[doc] Initial translation of views chapter.
"""Core hooks: check schema validity, unsure we are not deleting necessary
entities...
:organization: Logilab
:copyright: 2001-2008 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
"""
__docformat__ = "restructuredtext en"
from mx.DateTime import now
from cubicweb import UnknownProperty, ValidationError, BadConnectionId
from cubicweb.common.uilib import soup2xhtml
from cubicweb.server.pool import Operation, LateOperation, PreCommitOperation
from cubicweb.server.hookhelper import (check_internal_entity, previous_state,
get_user_sessions, rproperty)
from cubicweb.server.repository import FTIndexEntityOp
def relation_deleted(session, eidfrom, rtype, eidto):
session.add_query_data('pendingrelations', (eidfrom, rtype, eidto))
# base meta-data handling #####################################################
def setctime_before_add_entity(session, entity):
"""before create a new entity -> set creation and modification date
this is a conveniency hook, you shouldn't have to disable it
"""
if not 'creation_date' in entity:
entity['creation_date'] = now()
if not 'modification_date' in entity:
entity['modification_date'] = now()
def setmtime_before_update_entity(session, entity):
"""update an entity -> set modification date"""
if not 'modification_date' in entity:
entity['modification_date'] = now()
class SetCreatorOp(PreCommitOperation):
def precommit_event(self):
if self.eid in self.session.query_data('pendingeids', ()):
# entity have been created and deleted in the same transaction
return
ueid = self.session.user.eid
execute = self.session.unsafe_execute
if not execute('Any X WHERE X created_by U, X eid %(x)s',
{'x': self.eid}, 'x'):
execute('SET X created_by U WHERE X eid %(x)s, U eid %(u)s',
{'x': self.eid, 'u': ueid}, 'x')
def setowner_after_add_entity(session, entity):
"""create a new entity -> set owner and creator metadata"""
asession = session.actual_session()
if not asession.is_internal_session:
session.unsafe_execute('SET X owned_by U WHERE X eid %(x)s, U eid %(u)s',
{'x': entity.eid, 'u': asession.user.eid}, 'x')
SetCreatorOp(asession, eid=entity.eid)
def setis_after_add_entity(session, entity):
"""create a new entity -> set is relation"""
session.unsafe_execute('SET X is E WHERE X eid %(x)s, E name %(name)s',
{'x': entity.eid, 'name': entity.id}, 'x')
# XXX < 2.50 bw compat
if not session.get_shared_data('do-not-insert-is_instance_of'):
basetypes = entity.e_schema.ancestors() + [entity.e_schema]
session.unsafe_execute('SET X is_instance_of E WHERE X eid %%(x)s, E name IN (%s)' %
','.join("'%s'" % str(etype) for etype in basetypes),
{'x': entity.eid}, 'x')
def setowner_after_add_user(session, entity):
"""when a user has been created, add owned_by relation on itself"""
session.unsafe_execute('SET X owned_by X WHERE X eid %(x)s',
{'x': entity.eid}, 'x')
def fti_update_after_add_relation(session, eidfrom, rtype, eidto):
"""sync fulltext index when relevant relation is added. Reindexing the
contained entity is enough since it will implicitly reindex the container
entity.
"""
ftcontainer = session.repo.schema.rschema(rtype).fulltext_container
if ftcontainer == 'subject':
FTIndexEntityOp(session, entity=session.entity(eidto))
elif ftcontainer == 'object':
FTIndexEntityOp(session, entity=session.entity(eidfrom))
def fti_update_after_delete_relation(session, eidfrom, rtype, eidto):
"""sync fulltext index when relevant relation is deleted. Reindexing both
entities is necessary.
"""
if session.repo.schema.rschema(rtype).fulltext_container:
FTIndexEntityOp(session, entity=session.entity(eidto))
FTIndexEntityOp(session, entity=session.entity(eidfrom))
class SyncOwnersOp(PreCommitOperation):
def precommit_event(self):
self.session.unsafe_execute('SET X owned_by U WHERE C owned_by U, C eid %(c)s,'
'NOT EXISTS(X owned_by U, X eid %(x)s)',
{'c': self.compositeeid, 'x': self.composedeid},
('c', 'x'))
def sync_owner_after_add_composite_relation(session, eidfrom, rtype, eidto):
"""when adding composite relation, the composed should have the same owners
has the composite
"""
if rtype == 'wf_info_for':
# skip this special composite relation
return
composite = rproperty(session, rtype, eidfrom, eidto, 'composite')
if composite == 'subject':
SyncOwnersOp(session, compositeeid=eidfrom, composedeid=eidto)
elif composite == 'object':
SyncOwnersOp(session, compositeeid=eidto, composedeid=eidfrom)
def _register_metadata_hooks(hm):
"""register meta-data related hooks on the hooks manager"""
hm.register_hook(setctime_before_add_entity, 'before_add_entity', '')
hm.register_hook(setmtime_before_update_entity, 'before_update_entity', '')
hm.register_hook(setowner_after_add_entity, 'after_add_entity', '')
hm.register_hook(sync_owner_after_add_composite_relation, 'after_add_relation', '')
hm.register_hook(fti_update_after_add_relation, 'after_add_relation', '')
hm.register_hook(fti_update_after_delete_relation, 'after_delete_relation', '')
if 'is' in hm.schema:
hm.register_hook(setis_after_add_entity, 'after_add_entity', '')
if 'EUser' in hm.schema:
hm.register_hook(setowner_after_add_user, 'after_add_entity', 'EUser')
# core hooks ##################################################################
class DelayedDeleteOp(PreCommitOperation):
"""delete the object of composite relation except if the relation
has actually been redirected to another composite
"""
def precommit_event(self):
session = self.session
if not self.eid in session.query_data('pendingeids', ()):
etype = session.describe(self.eid)[0]
session.unsafe_execute('DELETE %s X WHERE X eid %%(x)s, NOT %s'
% (etype, self.relation),
{'x': self.eid}, 'x')
def handle_composite_before_del_relation(session, eidfrom, rtype, eidto):
"""delete the object of composite relation"""
composite = rproperty(session, rtype, eidfrom, eidto, 'composite')
if composite == 'subject':
DelayedDeleteOp(session, eid=eidto, relation='Y %s X' % rtype)
elif composite == 'object':
DelayedDeleteOp(session, eid=eidfrom, relation='X %s Y' % rtype)
def before_del_group(session, eid):
"""check that we don't remove the owners group"""
check_internal_entity(session, eid, ('owners',))
# schema validation hooks #####################################################
class CheckConstraintsOperation(LateOperation):
"""check a new relation satisfy its constraints
"""
def precommit_event(self):
eidfrom, rtype, eidto = self.rdef
# first check related entities have not been deleted in the same
# transaction
pending = self.session.query_data('pendingeids', ())
if eidfrom in pending:
return
if eidto in pending:
return
for constraint in self.constraints:
try:
constraint.repo_check(self.session, eidfrom, rtype, eidto)
except NotImplementedError:
self.critical('can\'t check constraint %s, not supported',
constraint)
def commit_event(self):
pass
def cstrcheck_after_add_relation(session, eidfrom, rtype, eidto):
"""check the relation satisfy its constraints
this is delayed to a precommit time operation since other relation which
will make constraint satisfied may be added later.
"""
constraints = rproperty(session, rtype, eidfrom, eidto, 'constraints')
if constraints:
CheckConstraintsOperation(session, constraints=constraints,
rdef=(eidfrom, rtype, eidto))
def uniquecstrcheck_before_modification(session, entity):
eschema = entity.e_schema
for attr, val in entity.items():
if val is None:
continue
if eschema.subject_relation(attr).is_final() and \
eschema.has_unique_values(attr):
rql = '%s X WHERE X %s %%(val)s' % (entity.e_schema, attr)
rset = session.unsafe_execute(rql, {'val': val})
if rset and rset[0][0] != entity.eid:
msg = session._('the value "%s" is already used, use another one')
raise ValidationError(entity.eid, {attr: msg % val})
class tidy_html_fields(object):
"""tidy HTML in rich text strings
FIXME: (adim) the whole idea of having a class is to store the
event type. There might be another way to get dynamically the
event inside the hook function.
"""
# FIXME hooks manager use func_name to register
func_name = 'tidy_html_field'
def __init__(self, event):
self.event = event
def __call__(self, session, entity):
for attr in entity.formatted_attrs():
value = entity.get(attr)
# text was not changed
if self.event == 'before_add_entity':
fmt = entity.get('%s_format' % attr)
else:
fmt = entity.get_value('%s_format' % attr)
if value and fmt == 'text/html':
entity[attr] = soup2xhtml(value, session.encoding)
class CheckRequiredRelationOperation(LateOperation):
"""checking relation cardinality has to be done after commit in
case the relation is being replaced
"""
eid, rtype = None, None
def precommit_event(self):
# recheck pending eids
if self.eid in self.session.query_data('pendingeids', ()):
return
if self.session.unsafe_execute(*self._rql()).rowcount < 1:
etype = self.session.describe(self.eid)[0]
msg = self.session._('at least one relation %(rtype)s is required on %(etype)s (%(eid)s)')
raise ValidationError(self.eid, {self.rtype: msg % {'rtype': self.rtype,
'etype': etype,
'eid': self.eid}})
def commit_event(self):
pass
def _rql(self):
raise NotImplementedError()
class CheckSRelationOp(CheckRequiredRelationOperation):
"""check required subject relation"""
def _rql(self):
return 'Any O WHERE S eid %%(x)s, S %s O' % self.rtype, {'x': self.eid}, 'x'
class CheckORelationOp(CheckRequiredRelationOperation):
"""check required object relation"""
def _rql(self):
return 'Any S WHERE O eid %%(x)s, S %s O' % self.rtype, {'x': self.eid}, 'x'
def checkrel_if_necessary(session, opcls, rtype, eid):
"""check an equivalent operation has not already been added"""
for op in session.pending_operations:
if isinstance(op, opcls) and op.rtype == rtype and op.eid == eid:
break
else:
opcls(session, rtype=rtype, eid=eid)
def cardinalitycheck_after_add_entity(session, entity):
"""check cardinalities are satisfied"""
eid = entity.eid
for rschema, targetschemas, x in entity.e_schema.relation_definitions():
# skip automatically handled relations
if rschema.type in ('owned_by', 'created_by', 'is', 'is_instance_of'):
continue
if x == 'subject':
subjtype = entity.e_schema
objtype = targetschemas[0].type
cardindex = 0
opcls = CheckSRelationOp
else:
subjtype = targetschemas[0].type
objtype = entity.e_schema
cardindex = 1
opcls = CheckORelationOp
card = rschema.rproperty(subjtype, objtype, 'cardinality')
if card[cardindex] in '1+':
checkrel_if_necessary(session, opcls, rschema.type, eid)
def cardinalitycheck_before_del_relation(session, eidfrom, rtype, eidto):
"""check cardinalities are satisfied"""
card = rproperty(session, rtype, eidfrom, eidto, 'cardinality')
pendingeids = session.query_data('pendingeids', ())
if card[0] in '1+' and not eidfrom in pendingeids:
checkrel_if_necessary(session, CheckSRelationOp, rtype, eidfrom)
if card[1] in '1+' and not eidto in pendingeids:
checkrel_if_necessary(session, CheckORelationOp, rtype, eidto)
def _register_core_hooks(hm):
hm.register_hook(handle_composite_before_del_relation, 'before_delete_relation', '')
hm.register_hook(before_del_group, 'before_delete_entity', 'EGroup')
#hm.register_hook(cstrcheck_before_update_entity, 'before_update_entity', '')
hm.register_hook(cardinalitycheck_after_add_entity, 'after_add_entity', '')
hm.register_hook(cardinalitycheck_before_del_relation, 'before_delete_relation', '')
hm.register_hook(cstrcheck_after_add_relation, 'after_add_relation', '')
hm.register_hook(uniquecstrcheck_before_modification, 'before_add_entity', '')
hm.register_hook(uniquecstrcheck_before_modification, 'before_update_entity', '')
hm.register_hook(tidy_html_fields('before_add_entity'), 'before_add_entity', '')
hm.register_hook(tidy_html_fields('before_update_entity'), 'before_update_entity', '')
# user/groups synchronisation #################################################
class GroupOperation(Operation):
"""base class for group operation"""
geid = None
def __init__(self, session, *args, **kwargs):
"""override to get the group name before actual groups manipulation:
we may temporarily loose right access during a commit event, so
no query should be emitted while comitting
"""
rql = 'Any N WHERE G eid %(x)s, G name N'
result = session.execute(rql, {'x': kwargs['geid']}, 'x', build_descr=False)
Operation.__init__(self, session, *args, **kwargs)
self.group = result[0][0]
class DeleteGroupOp(GroupOperation):
"""synchronize user when a in_group relation has been deleted"""
def commit_event(self):
"""the observed connections pool has been commited"""
groups = self.cnxuser.groups
try:
groups.remove(self.group)
except KeyError:
self.error('user %s not in group %s', self.cnxuser, self.group)
return
def after_del_in_group(session, fromeid, rtype, toeid):
"""modify user permission, need to update users"""
for session_ in get_user_sessions(session.repo, fromeid):
DeleteGroupOp(session, cnxuser=session_.user, geid=toeid)
class AddGroupOp(GroupOperation):
"""synchronize user when a in_group relation has been added"""
def commit_event(self):
"""the observed connections pool has been commited"""
groups = self.cnxuser.groups
if self.group in groups:
self.warning('user %s already in group %s', self.cnxuser,
self.group)
return
groups.add(self.group)
def after_add_in_group(session, fromeid, rtype, toeid):
"""modify user permission, need to update users"""
for session_ in get_user_sessions(session.repo, fromeid):
AddGroupOp(session, cnxuser=session_.user, geid=toeid)
class DelUserOp(Operation):
"""synchronize user when a in_group relation has been added"""
def __init__(self, session, cnxid):
self.cnxid = cnxid
Operation.__init__(self, session)
def commit_event(self):
"""the observed connections pool has been commited"""
try:
self.repo.close(self.cnxid)
except BadConnectionId:
pass # already closed
def after_del_user(session, eid):
"""modify user permission, need to update users"""
for session_ in get_user_sessions(session.repo, eid):
DelUserOp(session, session_.id)
def _register_usergroup_hooks(hm):
"""register user/group related hooks on the hooks manager"""
hm.register_hook(after_del_user, 'after_delete_entity', 'EUser')
hm.register_hook(after_add_in_group, 'after_add_relation', 'in_group')
hm.register_hook(after_del_in_group, 'after_delete_relation', 'in_group')
# workflow handling ###########################################################
def before_add_in_state(session, fromeid, rtype, toeid):
"""check the transition is allowed and record transition information
"""
assert rtype == 'in_state'
state = previous_state(session, fromeid)
etype = session.describe(fromeid)[0]
if not (session.is_super_session or 'managers' in session.user.groups):
if not state is None:
entity = session.entity(fromeid)
# we should find at least one transition going to this state
try:
iter(state.transitions(entity, toeid)).next()
except StopIteration:
msg = session._('transition is not allowed')
raise ValidationError(fromeid, {'in_state': msg})
else:
# not a transition
# check state is initial state if the workflow defines one
isrset = session.unsafe_execute('Any S WHERE ET initial_state S, ET name %(etype)s',
{'etype': etype})
if isrset and not toeid == isrset[0][0]:
msg = session._('not the initial state for this entity')
raise ValidationError(fromeid, {'in_state': msg})
eschema = session.repo.schema[etype]
if not 'wf_info_for' in eschema.object_relations():
# workflow history not activated for this entity type
return
rql = 'INSERT TrInfo T: T wf_info_for E, T to_state DS, T comment %(comment)s'
args = {'comment': session.get_shared_data('trcomment', None, pop=True),
'e': fromeid, 'ds': toeid}
cformat = session.get_shared_data('trcommentformat', None, pop=True)
if cformat is not None:
args['comment_format'] = cformat
rql += ', T comment_format %(comment_format)s'
restriction = ['DS eid %(ds)s, E eid %(e)s']
if not state is None: # not a transition
rql += ', T from_state FS'
restriction.append('FS eid %(fs)s')
args['fs'] = state.eid
rql = '%s WHERE %s' % (rql, ', '.join(restriction))
session.unsafe_execute(rql, args, 'e')
class SetInitialStateOp(PreCommitOperation):
"""make initial state be a default state"""
def precommit_event(self):
session = self.session
entity = self.entity
rset = session.execute('Any S WHERE ET initial_state S, ET name %(name)s',
{'name': str(entity.e_schema)})
# if there is an initial state and the entity's state is not set,
# use the initial state as a default state
pendingeids = session.query_data('pendingeids', ())
if rset and not entity.eid in pendingeids and not entity.in_state:
session.unsafe_execute('SET X in_state S WHERE X eid %(x)s, S eid %(s)s',
{'x' : entity.eid, 's' : rset[0][0]}, 'x')
def set_initial_state_after_add(session, entity):
SetInitialStateOp(session, entity=entity)
def _register_wf_hooks(hm):
"""register workflow related hooks on the hooks manager"""
if 'in_state' in hm.schema:
hm.register_hook(before_add_in_state, 'before_add_relation', 'in_state')
hm.register_hook(relation_deleted, 'before_delete_relation', 'in_state')
for eschema in hm.schema.entities():
if 'in_state' in eschema.subject_relations():
hm.register_hook(set_initial_state_after_add, 'after_add_entity',
str(eschema))
# EProperty hooks #############################################################
class DelEPropertyOp(Operation):
"""a user's custom properties has been deleted"""
def commit_event(self):
"""the observed connections pool has been commited"""
try:
del self.epropdict[self.key]
except KeyError:
self.error('%s has no associated value', self.key)
class ChangeEPropertyOp(Operation):
"""a user's custom properties has been added/changed"""
def commit_event(self):
"""the observed connections pool has been commited"""
self.epropdict[self.key] = self.value
class AddEPropertyOp(Operation):
"""a user's custom properties has been added/changed"""
def commit_event(self):
"""the observed connections pool has been commited"""
eprop = self.eprop
if not eprop.for_user:
self.repo.vreg.eprop_values[eprop.pkey] = eprop.value
# if for_user is set, update is handled by a ChangeEPropertyOp operation
def after_add_eproperty(session, entity):
key, value = entity.pkey, entity.value
try:
value = session.vreg.typed_value(key, value)
except UnknownProperty:
raise ValidationError(entity.eid, {'pkey': session._('unknown property key')})
except ValueError, ex:
raise ValidationError(entity.eid, {'value': session._(str(ex))})
if not session.user.matching_groups('managers'):
session.unsafe_execute('SET P for_user U WHERE P eid %(x)s,U eid %(u)s',
{'x': entity.eid, 'u': session.user.eid}, 'x')
else:
AddEPropertyOp(session, eprop=entity)
def after_update_eproperty(session, entity):
key, value = entity.pkey, entity.value
try:
value = session.vreg.typed_value(key, value)
except UnknownProperty:
return
except ValueError, ex:
raise ValidationError(entity.eid, {'value': session._(str(ex))})
if entity.for_user:
for session_ in get_user_sessions(session.repo, entity.for_user[0].eid):
ChangeEPropertyOp(session, epropdict=session_.user.properties,
key=key, value=value)
else:
# site wide properties
ChangeEPropertyOp(session, epropdict=session.vreg.eprop_values,
key=key, value=value)
def before_del_eproperty(session, eid):
for eidfrom, rtype, eidto in session.query_data('pendingrelations', ()):
if rtype == 'for_user' and eidfrom == eid:
# if for_user was set, delete has already been handled
break
else:
key = session.execute('Any K WHERE P eid %(x)s, P pkey K',
{'x': eid}, 'x')[0][0]
DelEPropertyOp(session, epropdict=session.vreg.eprop_values, key=key)
def after_add_for_user(session, fromeid, rtype, toeid):
if not session.describe(fromeid)[0] == 'EProperty':
return
key, value = session.execute('Any K,V WHERE P eid %(x)s,P pkey K,P value V',
{'x': fromeid}, 'x')[0]
if session.vreg.property_info(key)['sitewide']:
raise ValidationError(fromeid,
{'for_user': session._("site-wide property can't be set for user")})
for session_ in get_user_sessions(session.repo, toeid):
ChangeEPropertyOp(session, epropdict=session_.user.properties,
key=key, value=value)
def before_del_for_user(session, fromeid, rtype, toeid):
key = session.execute('Any K WHERE P eid %(x)s, P pkey K',
{'x': fromeid}, 'x')[0][0]
relation_deleted(session, fromeid, rtype, toeid)
for session_ in get_user_sessions(session.repo, toeid):
DelEPropertyOp(session, epropdict=session_.user.properties, key=key)
def _register_eproperty_hooks(hm):
"""register workflow related hooks on the hooks manager"""
hm.register_hook(after_add_eproperty, 'after_add_entity', 'EProperty')
hm.register_hook(after_update_eproperty, 'after_update_entity', 'EProperty')
hm.register_hook(before_del_eproperty, 'before_delete_entity', 'EProperty')
hm.register_hook(after_add_for_user, 'after_add_relation', 'for_user')
hm.register_hook(before_del_for_user, 'before_delete_relation', 'for_user')