# 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/>.
"""Core hooks: workflow related hooks
"""
__docformat__ = "restructuredtext en"
from datetime import datetime
from yams.schema import role_name
from cubicweb import RepositoryError, ValidationError
from cubicweb.interfaces import IWorkflowable
from cubicweb.selectors import implements
from cubicweb.server import hook
def _change_state(session, x, oldstate, newstate):
nocheck = session.transaction_data.setdefault('skip-security', set())
nocheck.add((x, 'in_state', oldstate))
nocheck.add((x, 'in_state', newstate))
# delete previous state first unless in_state isn't stored in the system
# source
fromsource = session.describe(x)[1]
if fromsource == 'system' or \
not session.repo.sources_by_uri[fromsource].support_relation('in_state'):
session.delete_relation(x, 'in_state', oldstate)
session.add_relation(x, 'in_state', newstate)
# operations ###################################################################
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) or entity.in_state) \
and entity.current_workflow:
state = entity.current_workflow.initial
if state:
session.add_relation(entity.eid, 'in_state', state.eid)
_FireAutotransitionOp(session, entity=entity)
class _FireAutotransitionOp(hook.Operation):
"""try to fire auto transition after state changes"""
def precommit_event(self):
entity = self.entity
autotrs = list(entity.possible_transitions('auto'))
if autotrs:
assert len(autotrs) == 1
entity.fire_transition(autotrs[0])
class _WorkflowChangedOp(hook.Operation):
"""fix entity current state when changing its workflow"""
def precommit_event(self):
# notice that enforcement that new workflow apply to the entity's type is
# done by schema rule, no need to check it here
session = self.session
pendingeids = session.transaction_data.get('pendingeids', ())
if self.eid in pendingeids:
return
entity = session.entity_from_eid(self.eid)
# check custom workflow has not been rechanged to another one in the same
# transaction
mainwf = entity.main_workflow
if mainwf.eid == self.wfeid:
deststate = mainwf.initial
if not deststate:
qname = role_name('custom_workflow', 'subject')
msg = session._('workflow has no initial state')
raise ValidationError(entity.eid, {qname: msg})
if mainwf.state_by_eid(entity.current_state.eid):
# nothing to do
return
# if there are no history, simply go to new workflow's initial state
if not entity.workflow_history:
if entity.current_state.eid != deststate.eid:
_change_state(session, entity.eid,
entity.current_state.eid, deststate.eid)
_FireAutotransitionOp(session, entity=entity)
return
msg = session._('workflow changed to "%s"')
msg %= session._(mainwf.name)
session.transaction_data[(entity.eid, 'customwf')] = self.wfeid
entity.change_state(deststate, msg, u'text/plain')
class _CheckTrExitPoint(hook.Operation):
def precommit_event(self):
tr = self.session.entity_from_eid(self.treid)
outputs = set()
for ep in tr.subworkflow_exit:
if ep.subwf_state.eid in outputs:
qname = role_name('subworkflow_exit', 'subject')
msg = self.session._("can't have multiple exits on the same state")
raise ValidationError(self.treid, {qname: msg})
outputs.add(ep.subwf_state.eid)
class _SubWorkflowExitOp(hook.Operation):
def precommit_event(self):
session = self.session
forentity = self.forentity
trinfo = self.trinfo
# we're in a subworkflow, check if we've reached an exit point
wftr = forentity.subworkflow_input_transition()
if wftr is None:
# inconsistency detected
qname = role_name('to_state', 'subject')
msg = session._("state doesn't belong to entity's current workflow")
raise ValidationError(self.trinfo.eid, {'to_state': msg})
tostate = wftr.get_exit_point(forentity, trinfo['to_state'])
if tostate is not None:
# reached an exit point
msg = session._('exiting from subworkflow %s')
msg %= session._(forentity.current_workflow.name)
session.transaction_data[(forentity.eid, 'subwfentrytr')] = True
forentity.change_state(tostate, msg, u'text/plain', tr=wftr)
# hooks ########################################################################
class WorkflowHook(hook.Hook):
__abstract__ = True
category = 'workflow'
class SetInitialStateHook(WorkflowHook):
__regid__ = 'wfsetinitial'
__select__ = WorkflowHook.__select__ & implements(IWorkflowable)
events = ('after_add_entity',)
def __call__(self):
_SetInitialStateOp(self._cw, entity=self.entity)
class PrepareStateChangeHook(WorkflowHook):
"""record previous state information"""
__regid__ = '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(WorkflowHook):
"""check the transition is allowed, add missing information. Expect that:
* wf_info_for inlined relation is set
* by_transition or to_state (managers only) inlined relation is set
"""
__regid__ = 'wffiretransition'
__select__ = WorkflowHook.__select__ & implements('TrInfo')
events = ('before_add_entity',)
def __call__(self):
session = self._cw
entity = self.entity
# first retreive entity to which the state change apply
try:
foreid = entity['wf_info_for']
except KeyError:
qname = role_name('wf_info_for', 'subject')
msg = session._('mandatory relation')
raise ValidationError(entity.eid, {qname: msg})
forentity = session.entity_from_eid(foreid)
# then check it has a workflow set, unless we're in the process of changing
# entity's workflow
if session.transaction_data.get((forentity.eid, 'customwf')):
wfeid = session.transaction_data[(forentity.eid, 'customwf')]
wf = session.entity_from_eid(wfeid)
else:
wf = forentity.current_workflow
if wf is None:
msg = session._('related entity has no workflow set')
raise ValidationError(entity.eid, {None: msg})
# then check it has a state set
fromstate = forentity.current_state
if fromstate is None:
msg = session._('related entity has no state')
raise ValidationError(entity.eid, {None: msg})
# True if we are coming back from subworkflow
swtr = session.transaction_data.pop((forentity.eid, 'subwfentrytr'), None)
cowpowers = (session.user.is_in_group('managers')
or not session.write_security)
# no investigate the requested state change...
try:
treid = entity['by_transition']
except KeyError:
# no transition set, check user is a manager and destination state
# is specified (and valid)
if not cowpowers:
qname = role_name('by_transition', 'subject')
msg = session._('mandatory relation')
raise ValidationError(entity.eid, {qname: msg})
deststateeid = entity.get('to_state')
if not deststateeid:
qname = role_name('by_transition', 'subject')
msg = session._('mandatory relation')
raise ValidationError(entity.eid, {qname: msg})
deststate = wf.state_by_eid(deststateeid)
if deststate is None:
qname = role_name('to_state', 'subject')
msg = session._("state doesn't belong to entity's workflow")
raise ValidationError(entity.eid, {qname: msg})
else:
# check transition is valid and allowed, unless we're coming back
# from subworkflow
tr = session.entity_from_eid(treid)
if swtr is None:
qname = role_name('by_transition', 'subject')
if tr is None:
msg = session._("transition doesn't belong to entity's workflow")
raise ValidationError(entity.eid, {qname: msg})
if not tr.has_input_state(fromstate):
msg = session._("transition %(tr)s isn't allowed from %(st)s") % {
'tr': session._(tr.name), 'st': session._(fromstate.name)}
raise ValidationError(entity.eid, {qname: msg})
if not tr.may_be_fired(foreid):
msg = session._("transition may not be fired")
raise ValidationError(entity.eid, {qname: msg})
if entity.get('to_state'):
deststateeid = entity['to_state']
if not cowpowers and deststateeid != tr.destination(forentity).eid:
qname = role_name('by_transition', 'subject')
msg = session._("transition isn't allowed")
raise ValidationError(entity.eid, {qname: msg})
if swtr is None:
deststate = session.entity_from_eid(deststateeid)
if not cowpowers and deststate is None:
qname = role_name('to_state', 'subject')
msg = session._("state doesn't belong to entity's workflow")
raise ValidationError(entity.eid, {qname: msg})
else:
deststateeid = tr.destination(forentity).eid
# everything is ok, add missing information on the trinfo entity
entity['from_state'] = fromstate.eid
entity['to_state'] = deststateeid
nocheck = session.transaction_data.setdefault('skip-security', set())
nocheck.add((entity.eid, 'from_state', fromstate.eid))
nocheck.add((entity.eid, 'to_state', deststateeid))
_FireAutotransitionOp(session, entity=forentity)
class FiredTransitionHook(WorkflowHook):
"""change related entity state"""
__regid__ = 'wffiretransition'
__select__ = WorkflowHook.__select__ & implements('TrInfo')
events = ('after_add_entity',)
def __call__(self):
trinfo = self.entity
_change_state(self._cw, trinfo['wf_info_for'],
trinfo['from_state'], trinfo['to_state'])
forentity = self._cw.entity_from_eid(trinfo['wf_info_for'])
assert forentity.current_state.eid == trinfo['to_state']
if forentity.main_workflow.eid != forentity.current_workflow.eid:
_SubWorkflowExitOp(self._cw, forentity=forentity, trinfo=trinfo)
class CheckInStateChangeAllowed(WorkflowHook):
"""check state apply, in case of direct in_state change using unsafe execute
"""
__regid__ = 'wfcheckinstate'
__select__ = WorkflowHook.__select__ & hook.match_rtype('in_state')
events = ('before_add_relation',)
def __call__(self):
session = self._cw
nocheck = session.transaction_data.get('skip-security', ())
if (self.eidfrom, 'in_state', self.eidto) in nocheck:
# state changed through TrInfo insertion, so we already know it's ok
return
entity = session.entity_from_eid(self.eidfrom)
mainwf = entity.main_workflow
if mainwf is None:
msg = session._('entity has no workflow set')
raise ValidationError(entity.eid, {None: msg})
for wf in mainwf.iter_workflows():
if wf.state_by_eid(self.eidto):
break
else:
qname = role_name('in_state', 'subject')
msg = session._("state doesn't belong to entity's workflow. You may "
"want to set a custom workflow for this entity first.")
raise ValidationError(self.eidfrom, {qname: msg})
if entity.current_workflow and wf.eid != entity.current_workflow.eid:
qname = role_name('in_state', 'subject')
msg = session._("state doesn't belong to entity's current workflow")
raise ValidationError(self.eidfrom, {qname: msg})
class SetModificationDateOnStateChange(WorkflowHook):
"""update entity's modification date after changing its state"""
__regid__ = '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)
class CheckWorkflowTransitionExitPoint(WorkflowHook):
"""check that there is no multiple exits from the same state"""
__regid__ = 'wfcheckwftrexit'
__select__ = WorkflowHook.__select__ & hook.match_rtype('subworkflow_exit')
events = ('after_add_relation',)
def __call__(self):
_CheckTrExitPoint(self._cw, treid=self.eidfrom)
class SetCustomWorkflow(WorkflowHook):
__regid__ = 'wfsetcustom'
__select__ = WorkflowHook.__select__ & hook.match_rtype('custom_workflow')
events = ('after_add_relation',)
def __call__(self):
_WorkflowChangedOp(self._cw, eid=self.eidfrom, wfeid=self.eidto)
class DelCustomWorkflow(SetCustomWorkflow):
__regid__ = 'wfdelcustom'
events = ('after_delete_relation',)
def __call__(self):
entity = self._cw.entity_from_eid(self.eidfrom)
typewf = entity.cwetype_workflow()
if typewf is not None:
_WorkflowChangedOp(self._cw, eid=self.eidfrom, wfeid=typewf.eid)