def _get_canonical_crystallized_state_root(db: BaseDB,
slot: int) -> Hash32:
validate_slot(slot)
slot_to_hash_key = SchemaV1.make_slot_to_crystallized_state_lookup_key(
slot)
try:
encoded_key = db[slot_to_hash_key]
except KeyError:
raise StateRootNotFound(
"No canonical crystallized state for slot #{0}".format(slot))
else:
return rlp.decode(encoded_key, sedes=rlp.sedes.binary)
def _add_slot_to_crystallized_state_lookup(
cls, db: BaseDB, crystallized_state: CrystallizedState) -> None:
"""
Set a record in the database to allow looking up this block by its
last state recalculation slot.
If it's a fork, store the old state root in `deletable_state_roots`.
"""
slot_to_hash_key = SchemaV1.make_slot_to_crystallized_state_lookup_key(
crystallized_state.last_state_recalc)
if db.exists(slot_to_hash_key):
deletable_state_roots = cls._get_deletable_state_roots(db)
replaced_state_root = rlp.decode(db[slot_to_hash_key],
sedes=rlp.sedes.binary)
cls._set_deletatable_state(
db,
deletable_state_roots + (replaced_state_root, ),
)
db.set(
slot_to_hash_key,
rlp.encode(crystallized_state.hash, sedes=rlp.sedes.binary),
)