def handle_cancelroute(
payment_state: InitiatorPaymentState,
state_change: ActionCancelRoute,
channelidentifiers_to_channels: typing.ChannelMap,
pseudo_random_generator: random.Random,
block_number: typing.BlockNumber,
) -> TransitionResult:
events: typing.List[Event] = list()
if can_cancel(payment_state):
old_initiator_state = payment_state.initiator
transfer_description = payment_state.initiator.transfer_description
cancel_events = cancel_current_route(payment_state)
msg = 'The previous transfer must be cancelled prior to trying a new route'
assert payment_state.initiator is None, msg
sub_iteration = initiator.try_new_route(
old_initiator_state=old_initiator_state,
channelidentifiers_to_channels=channelidentifiers_to_channels,
available_routes=state_change.routes,
transfer_description=transfer_description,
pseudo_random_generator=pseudo_random_generator,
block_number=block_number,
)
events.extend(cancel_events)
events.extend(sub_iteration.events)
assert sub_iteration.new_state
payment_state.initiator = sub_iteration.new_state
iteration = TransitionResult(payment_state, events)
return iteration
def handle_cancelroute(
payment_state: InitiatorPaymentState,
state_change: ActionCancelRoute,
channelidentifiers_to_channels: initiator.ChannelMap,
pseudo_random_generator: random.Random,
block_number: typing.BlockNumber,
) -> TransitionResult:
events = list()
if can_cancel(payment_state):
transfer_description = payment_state.initiator.transfer_description
cancel_events = cancel_current_route(payment_state)
msg = 'The previous transfer must be cancelled prior to trying a new route'
assert payment_state.initiator is None, msg
sub_iteration = initiator.try_new_route(
channelidentifiers_to_channels,
state_change.routes,
transfer_description,
pseudo_random_generator,
block_number,
)
events.extend(cancel_events)
events.extend(sub_iteration.events)
if sub_iteration.new_state:
payment_state.initiator = sub_iteration.new_state
else:
payment_state = None
iteration = TransitionResult(payment_state, events)
return iteration
def iteration_from_sub(
payment_state: InitiatorPaymentState,
iteration: TransitionResult,
) -> TransitionResult:
if iteration.new_state:
payment_state.initiator = iteration.new_state
return TransitionResult(payment_state, iteration.events)
return iteration
def iteration_from_sub(
payment_state: InitiatorPaymentState,
iteration: TransitionResult,
) -> TransitionResult:
if iteration.new_state:
payment_state.initiator = iteration.new_state
return TransitionResult(payment_state, iteration.events)
return iteration
def cancel_current_route(payment_state: InitiatorPaymentState) -> typing.List[Event]:
""" Cancel current route.
This allows a new route to be tried.
"""
assert can_cancel(payment_state), 'Cannot cancel a route after the secret is revealed'
transfer_description = payment_state.initiator.transfer_description
payment_state.cancelled_channels.append(payment_state.initiator.channel_identifier)
payment_state.initiator = None
return events_for_cancel_current_route(transfer_description)
def cancel_current_route(payment_state: InitiatorPaymentState) -> typing.List[Event]:
""" Cancel current route.
This allows a new route to be tried.
"""
assert can_cancel(payment_state), 'Cannot cancel a route after the secret is revealed'
transfer_description = payment_state.initiator.transfer_description
payment_state.cancelled_channels.append(payment_state.initiator.channel_identifier)
payment_state.initiator = None
return events_for_cancel_current_route(transfer_description)