def _get_state_root_by_slot(db: DatabaseAPI, slot: Slot) -> Hash32:
"""
Return the requested beacon state as specified by slot.
Raises StateNotFound if it is not present in the db.
"""
slot_to_state_root_key = SchemaV1.make_slot_to_state_root_lookup_key(slot)
try:
state_root = db[slot_to_state_root_key]
except KeyError:
raise StateNotFound("No state root for slot #{0}".format(slot))
else:
return Hash32(state_root)
def _get_state_by_root(db: DatabaseAPI, state_root: Hash32,
state_class: Type[BeaconState]) -> BeaconState:
"""
Return the requested beacon state as specified by state hash.
Raises StateNotFound if it is not present in the db.
"""
# TODO: validate_state_root
try:
state_ssz = db[state_root]
except KeyError:
raise StateNotFound(
f"No state with root {encode_hex(state_root)} found")
return _decode_state(state_ssz, state_class)