"""workflow definition and history related entities
: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 warnings import warn
from logilab.common.decorators import cached, clear_cache
from logilab.common.deprecation import deprecated
from cubicweb.entities import AnyEntity, fetch_config
from cubicweb.interfaces import IWorkflowable
from cubicweb.common.mixins import MI_REL_TRIGGERS
class WorkflowException(Exception): pass
class Workflow(AnyEntity):
id = 'Workflow'
@property
def initial(self):
"""return the initial state for this workflow"""
return self.initial_state and self.initial_state[0] or None
def is_default_workflow_of(self, etype):
"""return True if this workflow is the default workflow for the given
entity type
"""
return any(et for et in self.reverse_default_workflow
if et.name == etype)
def after_deletion_path(self):
"""return (path, parameters) which should be used as redirect
information when this entity is being deleted
"""
if self.workflow_of:
return self.workflow_of[0].rest_path(), {'vid': 'workflow'}
return super(Workflow, self).after_deletion_path()
def iter_workflows(self, _done=None):
"""return an iterator on actual workflows, eg this workflow and its
subworkflows
"""
# infinite loop safety belt
if _done is None:
_done = set()
yield self
_done.add(self.eid)
for tr in self.req.execute('Any T WHERE T is WorkflowTransition, '
'T transition_of WF, WF eid %(wf)s',
{'wf': self.eid}).entities():
if tr.subwf.eid in _done:
continue
for subwf in tr.subwf.iter_workflows(_done):
yield subwf
# state / transitions accessors ############################################
def state_by_name(self, statename):
rset = self.req.execute('Any S, SN WHERE S name SN, S name %(n)s, '
'S state_of WF, WF eid %(wf)s',
{'n': statename, 'wf': self.eid}, 'wf')
if rset:
return rset.get_entity(0, 0)
return None
def state_by_eid(self, eid):
rset = self.req.execute('Any S, SN WHERE S name SN, S eid %(s)s, '
'S state_of WF, WF eid %(wf)s',
{'s': eid, 'wf': self.eid}, ('wf', 's'))
if rset:
return rset.get_entity(0, 0)
return None
def transition_by_name(self, trname):
rset = self.req.execute('Any T, TN WHERE T name TN, T name %(n)s, '
'T transition_of WF, WF eid %(wf)s',
{'n': trname, 'wf': self.eid}, 'wf')
if rset:
return rset.get_entity(0, 0)
return None
def transition_by_eid(self, eid):
rset = self.req.execute('Any T, TN WHERE T name TN, T eid %(t)s, '
'T transition_of WF, WF eid %(wf)s',
{'t': eid, 'wf': self.eid}, ('wf', 't'))
if rset:
return rset.get_entity(0, 0)
return None
# wf construction methods ##################################################
def add_state(self, name, initial=False, **kwargs):
"""add a state to this workflow"""
state = self.req.create_entity('State', name=unicode(name), **kwargs)
self.req.execute('SET S state_of WF WHERE S eid %(s)s, WF eid %(wf)s',
{'s': state.eid, 'wf': self.eid}, ('s', 'wf'))
if initial:
assert not self.initial
self.req.execute('SET WF initial_state S '
'WHERE S eid %(s)s, WF eid %(wf)s',
{'s': state.eid, 'wf': self.eid}, ('s', 'wf'))
return state
def _add_transition(self, trtype, name, fromstates,
requiredgroups=(), conditions=(), **kwargs):
tr = self.req.create_entity(trtype, name=unicode(name), **kwargs)
self.req.execute('SET T transition_of WF '
'WHERE T eid %(t)s, WF eid %(wf)s',
{'t': tr.eid, 'wf': self.eid}, ('t', 'wf'))
assert fromstates, fromstates
if not isinstance(fromstates, (tuple, list)):
fromstates = (fromstates,)
for state in fromstates:
if hasattr(state, 'eid'):
state = state.eid
self.req.execute('SET S allowed_transition T '
'WHERE S eid %(s)s, T eid %(t)s',
{'s': state, 't': tr.eid}, ('s', 't'))
tr.set_transition_permissions(requiredgroups, conditions, reset=False)
return tr
def add_transition(self, name, fromstates, tostate,
requiredgroups=(), conditions=(), **kwargs):
"""add a transition to this workflow from some state(s) to another"""
tr = self._add_transition('Transition', name, fromstates,
requiredgroups, conditions, **kwargs)
if hasattr(tostate, 'eid'):
tostate = tostate.eid
self.req.execute('SET T destination_state S '
'WHERE S eid %(s)s, T eid %(t)s',
{'t': tr.eid, 's': tostate}, ('s', 't'))
return tr
def add_wftransition(self, name, subworkflow, fromstates, exitpoints,
requiredgroups=(), conditions=(), **kwargs):
"""add a workflow transition to this workflow"""
tr = self._add_transition('WorkflowTransition', name, fromstates,
requiredgroups, conditions, **kwargs)
if hasattr(subworkflow, 'eid'):
subworkflow = subworkflow.eid
self.req.execute('SET T subworkflow WF WHERE WF eid %(wf)s,T eid %(t)s',
{'t': tr.eid, 'wf': subworkflow}, ('wf', 't'))
for fromstate, tostate in exitpoints:
tr.add_exit_point(fromstate, tostate)
return tr
class BaseTransition(AnyEntity):
"""customized class for abstract transition
provides a specific may_be_fired method to check if the relation may be
fired by the logged user
"""
id = 'BaseTransition'
fetch_attrs, fetch_order = fetch_config(['name'])
def __init__(self, *args, **kwargs):
if self.id == 'BaseTransition':
raise WorkflowException('should not be instantiated')
super(BaseTransition, self).__init__(*args, **kwargs)
@property
def workflow(self):
return self.transition_of[0]
def has_input_state(self, state):
if hasattr(state, 'eid'):
state = state.eid
return any(s for s in self.reverse_allowed_transition if s.eid == state)
def may_be_fired(self, eid):
"""return true if the logged user may fire this transition
`eid` is the eid of the object on which we may fire the transition
"""
user = self.req.user
# check user is at least in one of the required groups if any
groups = frozenset(g.name for g in self.require_group)
if groups:
matches = user.matching_groups(groups)
if matches:
return matches
if 'owners' in groups and user.owns(eid):
return True
# check one of the rql expression conditions matches if any
if self.condition:
for rqlexpr in self.condition:
if rqlexpr.check_expression(self.req, eid):
return True
if self.condition or groups:
return False
return True
def after_deletion_path(self):
"""return (path, parameters) which should be used as redirect
information when this entity is being deleted
"""
if self.transition_of:
return self.transition_of[0].rest_path(), {}
return super(Transition, self).after_deletion_path()
def set_transition_permissions(self, requiredgroups=(), conditions=(),
reset=True):
"""set or add (if `reset` is False) groups and conditions for this
transition
"""
if reset:
self.req.execute('DELETE T require_group G WHERE T eid %(x)s',
{'x': self.eid}, 'x')
self.req.execute('DELETE T condition R WHERE T eid %(x)s',
{'x': self.eid}, 'x')
for gname in requiredgroups:
rset = self.req.execute('SET T require_group G '
'WHERE T eid %(x)s, G name %(gn)s',
{'x': self.eid, 'gn': gname}, 'x')
assert rset, '%s is not a known group' % gname
if isinstance(conditions, basestring):
conditions = (conditions,)
for expr in conditions:
if isinstance(expr, str):
expr = unicode(expr)
self.req.execute('INSERT RQLExpression X: X exprtype "ERQLExpression", '
'X expression %(expr)s, T condition X '
'WHERE T eid %(x)s',
{'x': self.eid, 'expr': expr}, 'x')
# XXX clear caches?
class Transition(BaseTransition):
"""customized class for Transition entities"""
id = 'Transition'
def destination(self):
return self.destination_state[0]
class WorkflowTransition(BaseTransition):
"""customized class for WorkflowTransition entities"""
id = 'WorkflowTransition'
@property
def subwf(self):
return self.subworkflow[0]
def destination(self):
return self.subwf.initial
def add_exit_point(self, fromstate, tostate):
if hasattr(fromstate, 'eid'):
fromstate = fromstate.eid
if hasattr(tostate, 'eid'):
tostate = tostate.eid
self.req.execute('INSERT SubWorkflowExitPoint X: T subworkflow_exit X, '
'X subworkflow_state FS, X destination_state TS '
'WHERE T eid %(t)s, FS eid %(fs)s, TS eid %(ts)s',
{'t': self.eid, 'fs': fromstate, 'ts': tostate},
('t', 'fs', 'ts'))
def get_exit_point(self, state):
"""if state is an exit point, return its associated destination state"""
if hasattr(state, 'eid'):
state = state.eid
stateeid = self.exit_points().get(state)
if stateeid is not None:
return self.req.entity_from_eid(stateeid)
return None
@cached
def exit_points(self):
result = {}
for ep in self.subworkflow_exit:
result[ep.subwf_state.eid] = ep.destination.eid
return result
def clear_all_caches(self):
super(WorkflowableMixIn, self).clear_all_caches()
clear_cache(self, 'exit_points')
class SubWorkflowExitPoint(AnyEntity):
"""customized class for SubWorkflowExitPoint entities"""
id = 'SubWorkflowExitPoint'
@property
def subwf_state(self):
return self.subworkflow_state[0]
@property
def destination(self):
return self.destination_state[0]
class State(AnyEntity):
"""customized class for State entities"""
id = 'State'
fetch_attrs, fetch_order = fetch_config(['name'])
rest_attr = 'eid'
@property
def workflow(self):
# take care, may be missing in multi-sources configuration
return self.state_of and self.state_of[0]
def after_deletion_path(self):
"""return (path, parameters) which should be used as redirect
information when this entity is being deleted
"""
if self.state_of:
return self.state_of[0].rest_path(), {}
return super(State, self).after_deletion_path()
class TrInfo(AnyEntity):
"""customized class for Transition information entities
"""
id = 'TrInfo'
fetch_attrs, fetch_order = fetch_config(['creation_date', 'comment'],
pclass=None) # don't want modification_date
@property
def for_entity(self):
return self.wf_info_for[0]
@property
def previous_state(self):
return self.from_state[0]
@property
def new_state(self):
return self.to_state[0]
@property
def transition(self):
return self.by_transition and self.by_transition[0] or None
def after_deletion_path(self):
"""return (path, parameters) which should be used as redirect
information when this entity is being deleted
"""
if self.for_entity:
return self.for_entity.rest_path(), {}
return 'view', {}
class WorkflowableMixIn(object):
"""base mixin providing workflow helper methods for workflowable entities.
This mixin will be automatically set on class supporting the 'in_state'
relation (which implies supporting 'wf_info_for' as well)
"""
__implements__ = (IWorkflowable,)
@property
def main_workflow(self):
"""return current workflow applied to this entity"""
if self.custom_workflow:
return self.custom_workflow[0]
return self.cwetype_workflow()
@property
def current_workflow(self):
"""return current workflow applied to this entity"""
return self.current_state and self.current_state.workflow or self.main_workflow
@property
def current_state(self):
"""return current state entity"""
return self.in_state and self.in_state[0] or None
@property
def state(self):
"""return current state name"""
try:
return self.in_state[0].name
except IndexError:
self.warning('entity %s has no state', self)
return None
@property
def printable_state(self):
"""return current state name translated to context's language"""
state = self.current_state
if state:
return self.req._(state.name)
return u''
@property
def workflow_history(self):
"""return the workflow history for this entity (eg ordered list of
TrInfo entities)
"""
return self.reverse_wf_info_for
def latest_trinfo(self):
"""return the latest transition information for this entity"""
return self.reverse_wf_info_for[-1]
@cached
def cwetype_workflow(self):
"""return the default workflow for entities of this type"""
# XXX CWEType method
wfrset = self.req.execute('Any WF WHERE X is ET, X eid %(x)s, '
'WF workflow_of ET', {'x': self.eid}, 'x')
if len(wfrset) == 1:
return wfrset.get_entity(0, 0)
if len(wfrset) > 1:
for wf in wfrset.entities():
if wf.is_default_workflow_of(self.id):
return wf
self.warning("can't find default workflow for %s", self.id)
else:
self.warning("can't find any workflow for %s", self.id)
return None
def possible_transitions(self):
"""generates transition that MAY be fired for the given entity,
expected to be in this state
"""
if self.current_state is None or self.current_workflow is None:
return
rset = self.req.execute(
'Any T,N WHERE S allowed_transition T, S eid %(x)s, '
'T name N, T transition_of WF, WF eid %(wfeid)s',
{'x': self.current_state.eid,
'wfeid': self.current_workflow.eid}, 'x')
for tr in rset.entities():
if tr.may_be_fired(self.eid):
yield tr
def _add_trinfo(self, comment, commentformat, treid=None, tseid=None):
kwargs = {}
if comment is not None:
kwargs['comment'] = comment
if commentformat is not None:
kwargs['comment_format'] = commentformat
args = [('wf_info_for', 'E')]
kwargs['E'] = self.eid
if treid is not None:
args.append( ('by_transition', 'T') )
kwargs['T'] = treid
if tseid is not None:
args.append( ('to_state', 'S') )
kwargs['S'] = tseid
return self.req.create_entity('TrInfo', *args, **kwargs)
def fire_transition(self, trname, comment=None, commentformat=None):
"""change the entity's state by firing transition of the given name in
entity's workflow
"""
assert self.current_workflow
tr = self.current_workflow.transition_by_name(trname)
assert tr is not None, 'not a %s transition: %s' % (self.id, trname)
return self._add_trinfo(comment, commentformat, tr.eid)
def change_state(self, statename, comment=None, commentformat=None, tr=None):
"""change the entity's state to the given state (name or entity) in
entity's workflow. This method should only by used by manager to fix an
entity's state when their is no matching transition, otherwise
fire_transition should be used.
"""
assert self.current_workflow
if hasattr(statename, 'eid'):
stateeid = statename.eid
else:
if not isinstance(statename, basestring):
warn('give a state name')
state = self.current_workflow.state_by_eid(statename)
else:
state = self.current_workflow.state_by_name(statename)
if state is None:
raise WorkflowException('not a %s state: %s' % (self.id,
statename))
stateeid = state.eid
# XXX try to find matching transition?
return self._add_trinfo(comment, commentformat, tr and tr.eid, stateeid)
def subworkflow_input_transition(self):
"""return the transition which has went through the current sub-workflow
"""
if self.main_workflow.eid == self.current_workflow.eid:
return # doesn't make sense
subwfentries = []
for trinfo in reversed(self.workflow_history):
if (trinfo.transition and
trinfo.previous_state.workflow.eid != trinfo.new_state.workflow.eid):
# entering or leaving a subworkflow
if (subwfentries and
subwfentries[-1].new_state.workflow.eid == trinfo.previous_state.workflow.eid):
# leave
del subwfentries[-1]
else:
# enter
subwfentries.append(trinfo)
if not subwfentries:
return None
return subwfentries[-1].transition
def clear_all_caches(self):
super(WorkflowableMixIn, self).clear_all_caches()
clear_cache(self, 'cwetype_workflow')
@deprecated('get transition from current workflow and use its may_be_fired method')
def can_pass_transition(self, trname):
"""return the Transition instance if the current user can fire the
transition with the given name, else None
"""
tr = self.current_workflow and self.current_workflow.transition_by_name(trname)
if tr and tr.may_be_fired(self.eid):
return tr
@property
@deprecated('use printable_state')
def displayable_state(self):
return self.req._(self.state)
MI_REL_TRIGGERS[('in_state', 'subject')] = WorkflowableMixIn