def restore_state(
transition_function: Callable,
storage: SerializedSQLiteStorage,
state_change_identifier: StateChangeID,
node_address: Address,
) -> Optional[State]:
snapshot = storage.get_snapshot_before_state_change(
state_change_identifier=state_change_identifier)
if snapshot is None:
return None
log.debug(
"Snapshot found",
from_state_change_id=snapshot.state_change_identifier,
to_state_change_id=state_change_identifier,
node=to_checksum_address(node_address),
)
state, _ = replay_state_changes(
node_address=node_address,
state=snapshot.data,
state_change_range=Range(snapshot.state_change_identifier,
state_change_identifier),
storage=storage,
transition_function=transition_function,
)
return state
def restore_to_state_change(
transition_function: Callable,
storage: SerializedSQLiteStorage,
state_change_identifier: StateChangeID,
node_address: Address,
) -> Tuple[int, int, "WriteAheadLog"]:
chain_state: Optional[State]
from_identifier: StateChangeID
snapshot = storage.get_snapshot_before_state_change(
state_change_identifier=state_change_identifier)
if snapshot is not None:
log.debug(
"Restoring from snapshot",
from_state_change_id=snapshot.state_change_identifier,
to_state_change_id=state_change_identifier,
node=to_checksum_address(node_address),
)
from_identifier = snapshot.state_change_identifier
chain_state = snapshot.data
state_change_qty = snapshot.state_change_qty
else:
log.debug(
"No snapshot found, replaying all state changes",
to_state_change_id=state_change_identifier,
node=to_checksum_address(node_address),
)
from_identifier = LOW_STATECHANGE_ULID
chain_state = None
state_change_qty = 0
state_manager = StateManager(transition_function, chain_state)
wal = WriteAheadLog(state_manager, storage)
unapplied_state_changes = storage.get_statechanges_by_range(
Range(from_identifier, state_change_identifier))
if unapplied_state_changes:
log.debug(
"Replaying state changes",
replayed_state_changes=[
redact_secret(DictSerializer.serialize(state_change))
for state_change in unapplied_state_changes
],
node=to_checksum_address(node_address),
)
for state_change in unapplied_state_changes:
wal.state_manager.dispatch(state_change)
return state_change_qty, len(unapplied_state_changes), wal
def test_get_state_change_with_balance_proof():
""" All state changes which contain a balance proof must be found when
querying the database.
"""
serializer = JSONSerializer()
storage = SerializedSQLiteStorage(":memory:", serializer)
counter = itertools.count()
balance_proof = make_signed_balance_proof_from_counter(counter)
lock_expired = ReceiveLockExpired(
sender=balance_proof.sender,
balance_proof=balance_proof,
secrethash=factories.make_secret_hash(next(counter)),
message_identifier=MessageID(next(counter)),
)
received_balance_proof = make_signed_balance_proof_from_counter(counter)
unlock = ReceiveUnlock(
sender=received_balance_proof.sender,
message_identifier=MessageID(next(counter)),
secret=factories.make_secret(next(counter)),
balance_proof=received_balance_proof,
)
transfer = make_signed_transfer_from_counter(counter)
transfer_refund = ReceiveTransferRefund(
transfer=transfer,
balance_proof=transfer.balance_proof,
sender=transfer.balance_proof.sender, # pylint: disable=no-member
)
transfer = make_signed_transfer_from_counter(counter)
transfer_reroute = ActionTransferReroute(
transfer=transfer,
balance_proof=transfer.balance_proof,
sender=transfer.balance_proof.sender, # pylint: disable=no-member
secret=sha3(factories.make_secret(next(counter))),
)
mediator_from_route, mediator_signed_transfer = make_from_route_from_counter(
counter)
action_init_mediator = ActionInitMediator(
route_states=[
RouteState(
route=[factories.make_address(),
factories.make_address()],
forward_channel_id=factories.make_channel_identifier(),
)
],
from_hop=mediator_from_route,
from_transfer=mediator_signed_transfer,
balance_proof=mediator_signed_transfer.balance_proof,
sender=mediator_signed_transfer.balance_proof.sender, # pylint: disable=no-member
)
target_from_route, target_signed_transfer = make_from_route_from_counter(
counter)
action_init_target = ActionInitTarget(
from_hop=target_from_route,
transfer=target_signed_transfer,
balance_proof=target_signed_transfer.balance_proof,
sender=target_signed_transfer.balance_proof.sender, # pylint: disable=no-member
)
statechanges_balanceproofs = [
(lock_expired, lock_expired.balance_proof),
(unlock, unlock.balance_proof),
(transfer_refund, transfer_refund.transfer.balance_proof),
(transfer_reroute, transfer_reroute.transfer.balance_proof),
(action_init_mediator,
action_init_mediator.from_transfer.balance_proof),
(action_init_target, action_init_target.transfer.balance_proof),
]
assert storage.count_state_changes() == 0
state_change_ids = storage.write_state_changes(
[state_change for state_change, _ in statechanges_balanceproofs])
assert storage.count_state_changes() == len(statechanges_balanceproofs)
msg_in_order = "Querying must return state changes in order"
stored_statechanges_records = storage.get_statechanges_records_by_range(
RANGE_ALL_STATE_CHANGES)
assert len(stored_statechanges_records) == 6, msg_in_order
pair_elements = zip(statechanges_balanceproofs, state_change_ids,
stored_statechanges_records)
for statechange_balanceproof, statechange_id, record in pair_elements:
assert record.data == statechange_balanceproof[0], msg_in_order
assert record.state_change_identifier == statechange_id, msg_in_order
# Make sure state changes are returned in the correct order in which they were stored
stored_statechanges = storage.get_statechanges_by_range(
Range(
stored_statechanges_records[1].state_change_identifier,
stored_statechanges_records[2].state_change_identifier,
))
assert len(stored_statechanges) == 2
assert isinstance(stored_statechanges[0], ReceiveUnlock)
assert isinstance(stored_statechanges[1], ReceiveTransferRefund)
for state_change, balance_proof in statechanges_balanceproofs:
state_change_record = get_state_change_with_balance_proof_by_balance_hash(
storage=storage,
canonical_identifier=balance_proof.canonical_identifier,
sender=balance_proof.sender,
balance_hash=balance_proof.balance_hash,
)
assert state_change_record
assert state_change_record.data == state_change
state_change_record = get_state_change_with_balance_proof_by_locksroot(
storage=storage,
canonical_identifier=balance_proof.canonical_identifier,
sender=balance_proof.sender,
locksroot=balance_proof.locksroot,
)
assert state_change_record
assert state_change_record.data == state_change
storage.close()