+
−"""Core hooks: workflow related hooks
+
−
+
−: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 datetime import datetime
+
−
+
−from cubicweb import RepositoryError, ValidationError
+
−from cubicweb.interfaces import IWorkflowable
+
−from cubicweb.selectors import entity_implements
+
−from cubicweb.server import hook
+
−
+
−
+
−def previous_state(session, eid):
+
−    """return the state of the entity with the given eid,
+
−    usually since it's changing in the current transaction. Due to internal
+
−    relation hooks, the relation may has been deleted at this point, so
+
−    we have handle that
+
−    """
+
−    if session.added_in_transaction(eid):
+
−        return
+
−    pending = session.transaction_data.get('pendingrelations', ())
+
−    for eidfrom, rtype, eidto in reversed(pending):
+
−        if rtype == 'in_state' and eidfrom == eid:
+
−            rset = session.execute('Any S,N WHERE S eid %(x)s, S name N',
+
−                                   {'x': eidto}, 'x')
+
−            return rset.get_entity(0, 0)
+
−    rset = session.execute('Any S,N WHERE X eid %(x)s, X in_state S, S name N',
+
−                           {'x': eid}, 'x')
+
−    if rset:
+
−        return rset.get_entity(0, 0)
+
−
+
−
+
−def relation_deleted(session, eidfrom, rtype, eidto):
+
−    session.transaction_data.setdefault('pendingrelations', []).append(
+
−        (eidfrom, rtype, eidto))
+
−
+
−
+
−class _SetInitialStateOp(hook.Operation):
+
−    """make initial state be a default state"""
+
−
+
−    def precommit_event(self):
+
−        session = self.session
+
−        entity = self.entity
+
−        # if there is an initial state and the entity's state is not set,
+
−        # use the initial state as a default state
+
−        if not session.deleted_in_transaction(entity.eid) and not entity.in_state:
+
−            rset = session.execute('Any S WHERE ET initial_state S, ET name %(name)s',
+
−                                   {'name': entity.id})
+
−            if rset:
+
−                session.add_relation(entity.eid, 'in_state', rset[0][0])
+
−
+
−class WorkflowHook(hook.Hook):
+
−    __abstract__ = True
+
−    category = 'worfklow'
+
−
+
−
+
−class SetInitialStateHook(WorkflowHook):
+
−    __id__ = 'wfsetinitial'
+
−    __select__ = WorkflowHook.__select__ & entity_implements(IWorkflowable)
+
−    events = ('after_add_entity',)
+
−
+
−    def __call__(self):
+
−        _SetInitialStateOp(self._cw, entity=self.entity)
+
−
+
−
+
−class PrepareStateChangeHook(WorkflowHook):
+
−    """record previous state information"""
+
−    __id__ = 'cwdelstate'
+
−    __select__ = WorkflowHook.__select__ & hook.match_rtype('in_state')
+
−    events = ('before_delete_relation',)
+
−
+
−    def __call__(self):
+
−        self._cw.transaction_data.setdefault('pendingrelations', []).append(
+
−            (self.eidfrom, self.rtype, self.eidto))
+
−
+
−
+
−class FireTransitionHook(PrepareStateChangeHook):
+
−    """check the transition is allowed and record transition information"""
+
−    __id__ = 'wffiretransition'
+
−    events = ('before_add_relation',)
+
−
+
−    def __call__(self):
+
−        session = self._cw
+
−        eidfrom = self.eidfrom
+
−        eidto = self.eidto
+
−        state = previous_state(session, eidfrom)
+
−        etype = session.describe(eidfrom)[0]
+
−        if not (session.is_super_session or 'managers' in session.user.groups):
+
−            if not state is None:
+
−                entity = session.entity_from_eid(eidfrom)
+
−                # we should find at least one transition going to this state
+
−                try:
+
−                    iter(state.transitions(entity, eidto)).next()
+
−                except StopIteration:
+
−                    msg = session._('transition is not allowed')
+
−                    raise ValidationError(eidfrom, {'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 eidto == isrset[0][0]:
+
−                    msg = session._('not the initial state for this entity')
+
−                    raise ValidationError(eidfrom, {'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': eidfrom, 'ds': eidto}
+
−        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 SetModificationDateOnStateChange(WorkflowHook):
+
−    """update entity's modification date after changing its state"""
+
−    __id__ = 'wfsyncmdate'
+
−    __select__ = WorkflowHook.__select__ & hook.match_rtype('in_state')
+
−    events = ('after_add_relation',)
+
−
+
−    def __call__(self):
+
−        if self._cw.added_in_transaction(self.eidfrom):
+
−            # new entity, not needed
+
−            return
+
−        entity = self._cw.entity_from_eid(self.eidfrom)
+
−        try:
+
−            entity.set_attributes(modification_date=datetime.now())
+
−        except RepositoryError, ex:
+
−            # usually occurs if entity is coming from a read-only source
+
−            # (eg ldap user)
+
−            self.warning('cant change modification date for %s: %s', entity, ex)