def _read_state_randao_mixes(self, state_root: Root,
EPOCHS_PER_HISTORICAL_VECTOR: int,
SLOTS_PER_EPOCH: int) -> Iterable[Root]:
"""
Reconstructs the ``randao_mixes`` at a given state root.
"""
state_slot = self._read_state_slot(state_root)
state_epoch = compute_epoch_at_slot(state_slot, SLOTS_PER_EPOCH)
finalized_slot = self.get_finalized_head(BeaconBlock).slot
non_finalized_state_roots = dict(
enumerate(
self.get_state_parents(state_root,
state_slot - finalized_slot),
finalized_slot,
))
# create a list of epochs that corresponds to each mix in ``state.randao_mixes``
epochs = [
Epoch(n)
for n in range(state_epoch - EPOCHS_PER_HISTORICAL_VECTOR +
1, state_epoch + 1)
]
offset = EPOCHS_PER_HISTORICAL_VECTOR - epochs[
0] % EPOCHS_PER_HISTORICAL_VECTOR
epochs = epochs[offset:] + epochs[:offset]
genesis_root = self._read_state_root_at_slot(Slot(0))
genesis_randao_mix = Root(
Hash32(self.db[SchemaV1.state_root_to_randao_mix(genesis_root)]))
for epoch in epochs:
if epoch < 0:
yield genesis_randao_mix
elif epoch == state_epoch:
# yield the randao mix at the particular slot
key = SchemaV1.state_root_to_randao_mix(state_root)
yield Root(Hash32(self.db[key]))
else:
# yield the randao mix at the last slot in the epoch
slot = Slot((epoch + 1) * SLOTS_PER_EPOCH - 1)
if slot in non_finalized_state_roots:
root = non_finalized_state_roots[slot]
else:
root = self._read_state_root_at_slot(slot)
key = SchemaV1.state_root_to_randao_mix(root)
yield Root(Hash32(self.db[key]))
def get_state_by_slot(self, slot: Slot, state_class: Type[BeaconState],
config: Eth2Config) -> Optional[BeaconState]:
key = SchemaV1.slot_to_state_root(slot)
try:
root = Root(Hash32(self.db[key]))
except KeyError:
return None
return self.get_state_by_root(root, state_class, config)
def get_block_by_slot(
self, slot: Slot,
block_class: Type[BaseBeaconBlock]) -> Optional[BaseBeaconBlock]:
key = SchemaV1.slot_to_block_root(slot)
try:
root = Root(Hash32(self.db[key]))
except KeyError:
return None
return self.get_block_by_root(root, block_class)
def _bytes_to_roots(roots_bytes: bytes) -> Iterable[Root]:
bytes_len = len(roots_bytes)
if bytes_len % 32 != 0:
raise ValueError("bytes not divisible by 32")
for i in range(0, int(bytes_len / 32)):
start = i * 32
end = start + 32
yield Root(Hash32(roots_bytes[start:end]))
def _read_state_balances(self, state_root: Root,
VALIDATOR_REGISTRY_LIMIT: int) -> Tuple[Gwei]:
state_root_to_balances_root = SchemaV1.state_root_to_balances_root(
state_root)
balances_root = Root(Hash32(self.db[state_root_to_balances_root]))
balances_root_to_balances = SchemaV1.balances_root_to_balances(
balances_root)
return ssz.decode(
self.db[balances_root_to_balances],
ssz.List(ssz.uint64, VALIDATOR_REGISTRY_LIMIT),
)
def _read_state_validators(self, state_root: Root) -> Iterable[Validator]:
state_root_to_validators_root = SchemaV1.state_root_to_validators_root(
state_root)
validators_root = Root(Hash32(self.db[state_root_to_validators_root]))
validators_root_to_roots_of_validators = SchemaV1.validators_root_to_roots_of_validators(
validators_root)
roots = _bytes_to_roots(
self.db[validators_root_to_roots_of_validators])
for root in roots:
yield ssz.decode(self.db[bytes(root)], Validator)
def _read_state_block_roots(
self, state_root: Root,
SLOTS_PER_HISTORICAL_ROOT: int) -> Iterable[Root]:
"""
Reconstructs ``state.block_roots`` at a given state root.
"""
for root in self._read_state_state_roots(state_root,
SLOTS_PER_HISTORICAL_ROOT):
if root == default_root:
yield default_root
else:
key = SchemaV1.state_root_to_latest_block_header_root(root)
yield Root(Hash32(self.db[key]))
def get_finalized_head(
self, block_class: Type[BaseBeaconBlock]) -> BaseBeaconBlock:
finalized_head_root_key = SchemaV1.finalized_head_root()
finalized_head_root = Root(Hash32(self.db[finalized_head_root_key]))
return self.get_block_by_root(finalized_head_root, block_class)
def _read_state_root_at_slot(self, slot: Slot) -> Root:
key = SchemaV1.slot_to_state_root(slot)
return Root(Hash32(self.db[key]))
def _read_state_parent_state_root(self, state_root: Root) -> Root:
key = SchemaV1.state_root_to_parent_state_root(state_root)
return Root(Hash32(self.db[key]))
def _read_state_block_header(self, state_root: Root) -> BeaconBlockHeader:
block_root = Root(
Hash32(self.db[SchemaV1.state_root_to_latest_block_header_root(
state_root)]))
key = SchemaV1.block_root_to_block_header(block_root)
return ssz.decode(self.db[key], BeaconBlockHeader)
def get_justified_head(
self, block_class: Type[BaseBeaconBlock]) -> BaseBeaconBlock:
justified_head_root_key = SchemaV1.justified_head_root()
justified_head_root = Root(Hash32(self.db[justified_head_root_key]))
return self.get_block_by_root(justified_head_root, block_class)
def get_canonical_head(
self, block_class: Type[BaseBeaconBlock]) -> BaseBeaconBlock:
canonical_head_root_key = SchemaV1.canonical_head_root()
canonical_head_root = Root(Hash32(self.db[canonical_head_root_key]))
return self.get_block_by_root(canonical_head_root, block_class)