class state_info(object):
"""
An extra object that hijacks the actual state methods.
"""
@property
def name(si_self):
"""
The name of the current state
"""
return getattr(self, field)
@property
def description(si_self):
"""
The description of the current state
"""
si = machine.get_state(getattr(self, field))
return si.description
@property
def in_group(si_self):
"""
In what groups is this state? It's a dictionary that will return
``True`` for the state groups that this state is in.
"""
return machine.get_state_groups(getattr(self, field))
def possible_transitions(si_self):
"""
Return list of transitions which can be made from the current
state.
"""
for name in machine.transitions:
t = machine.transitions[name]
if getattr(self, field) in t.from_states:
yield t
def test_transition(si_self, transition, user=None):
"""
Check whether we could execute this transition.
:param str transition: the transition name
:param user: the user that will execute the transition. Used for
permission checking
:type: :class:`django.contrib.auth.models.User` or ``None``
:returns:``True`` when we expect this transition to be executed
successfully. It will raise an ``Exception`` when this
transition is impossible or not allowed.
"""
# Transition name should be known
if not machine.has_transition(transition):
raise UnknownTransition(self, transition)
t = machine.get_transitions(transition)
if getattr(self, field) not in t.from_states:
raise TransitionCannotStart(self, transition)
# User should have permissions for this transition
if user and not t.has_permission(self, user):
raise PermissionDenied(self, transition, user)
# Transition should validate
validation_errors = list(t.validate(self))
if validation_errors:
raise TransitionNotValidated(si_self, transition,
validation_errors)
return True
def make_transition(si_self, transition, user=None, **kwargs):
"""
Executes state transition.
:param str transition: the transition name
:param user: the user that will execute the transition. Used for
permission checking
:type: :class:`django.contrib.auth.models.User` or ``None``
:param dict kwargs: the kwargs that will be passed to
:meth:`~django_states.machine.StateTransition.handler`
"""
# Transition name should be known
if not machine.has_transition(transition):
raise UnknownTransition(self, transition)
t = machine.get_transitions(transition)
_state_log_model = getattr(self, '_%s_log_model' % field, None)
# Start transition log
if _state_log_model:
# Try to serialize kwargs, for the log. Save null
# when it's not serializable.
try:
serialized_kwargs = json.dumps(kwargs)
except TypeError:
serialized_kwargs = json.dumps(None)
transition_log = _state_log_model.objects.create(
on=self,
from_state=getattr(self, field),
to_state=t.to_state,
user=user,
serialized_kwargs=serialized_kwargs)
# Test transition (access/execution validation)
try:
si_self.test_transition(transition, user)
except TransitionException, e:
if _state_log_model:
transition_log.make_transition('fail')
raise e
# Execute
if _state_log_model:
transition_log.make_transition('start')
try:
from_state = getattr(self, field)
before_state_execute.send(sender=self,
from_state=from_state,
to_state=t.to_state)
# First call handler (handler should still see the original
# state.)
t.handler(self, user, **kwargs)
# Then set new state and save.
setattr(self, field, t.to_state)
self.save()
after_state_execute.send(sender=self,
from_state=from_state,
to_state=t.to_state)
except Exception, e:
if _state_log_model:
transition_log.make_transition('fail')
# Print original traceback for debugging
import traceback
traceback.print_exc()
raise e
def make_transition(si_self, transition, user=None, **kwargs):
"""
Executes state transition.
:param str transition: the transition name
:param user: the user that will execute the transition. Used for
permission checking
:type: :class:`django.contrib.auth.models.User` or ``None``
:param dict kwargs: the kwargs that will be passed to
:meth:`~django_states.machine.StateTransition.handler`
"""
# Transition name should be known
if not machine.has_transition(transition):
raise UnknownTransition(self, transition)
t = machine.get_transitions(transition)
_state_log_model = getattr(self, '_%s_log_model' % field, None)
# Start transition log
if _state_log_model:
# Try to serialize kwargs, for the log. Save null
# when it's not serializable.
try:
serialized_kwargs = json.dumps(kwargs)
except TypeError:
serialized_kwargs = json.dumps(None)
transition_log = _state_log_model.objects.create(
on=self, from_state=getattr(self, field), to_state=t.to_state,
user=user, serialized_kwargs=serialized_kwargs)
# Test transition (access/execution validation)
try:
si_self.test_transition(transition, user)
except TransitionException as e:
if _state_log_model:
transition_log.make_transition('fail')
raise e
# Execute
if _state_log_model:
transition_log.make_transition('start')
try:
from_state = getattr(self, field)
before_state_execute.send(sender=self,
from_state=from_state,
to_state=t.to_state)
# First call handler (handler should still see the original
# state.)
t.handler(self, user, **kwargs)
# Then set new state and save.
setattr(self, field, t.to_state)
self.save()
after_state_execute.send(sender=self,
from_state=from_state,
to_state=t.to_state)
except Exception as e:
if _state_log_model:
transition_log.make_transition('fail')
raise
else:
if _state_log_model:
transition_log.make_transition('complete')
# *After completion*, call the handler of this state
# definition
machine.get_state(t.to_state).handler(self)
def make_transition(si_self, transition, user=None, **kwargs):
"""
Executes state transition.
:param str transition: the transition name
:param user: the user that will execute the transition. Used for
permission checking
:type: :class:`django.contrib.auth.models.User` or ``None``
:param dict kwargs: the kwargs that will be passed to
:meth:`~django_states.machine.StateTransition.handler`
"""
# Transition name should be known
if not machine.has_transition(transition):
raise UnknownTransition(self, transition)
t = machine.get_transitions(transition)
_state_log_model = getattr(self, "_{}_log_model".format(field),
None)
# Start transition log
if _state_log_model:
# Try to serialize kwargs, for the log. Save null
# when it's not serializable.
try:
serialized_kwargs = json.dumps(kwargs)
except TypeError:
serialized_kwargs = json.dumps(None)
transition_log = _state_log_model.objects.create(
on=self,
from_state=getattr(self, field),
to_state=t.to_state,
user=user,
serialized_kwargs=serialized_kwargs,
)
# Test transition (access/execution validation)
try:
si_self.test_transition(transition, user)
except TransitionException as e:
if _state_log_model:
transition_log.make_transition("fail")
raise e
# Execute
if _state_log_model:
transition_log.make_transition("start")
try:
from_state = getattr(self, field)
before_state_execute.send(sender=self,
from_state=from_state,
to_state=t.to_state)
# First call handler (handler should still see the original
# state.)
t.handler(self, user, **kwargs)
# Then set new state and save.
setattr(self, field, t.to_state)
self.save()
after_state_execute.send(sender=self,
from_state=from_state,
to_state=t.to_state)
except Exception as e:
if _state_log_model:
transition_log.make_transition("fail")
raise
else:
if _state_log_model:
transition_log.make_transition("complete")
# *After completion*, call the handler of this state
# definition
machine.get_state(t.to_state).handler(self)