def test_get_beacon_proposer_index(genesis_state, config):
# TODO(hwwhww) find a way to normalize validator effective balance distribution.
state = genesis_state
validators = tuple([
state.validators[index].set("effective_balance",
config.MAX_EFFECTIVE_BALANCE)
for index in range(len(state.validators))
])
for slot in range(0, config.SLOTS_PER_EPOCH):
state = state.mset("slot", slot, "validators", validators)
proposer_index = get_beacon_proposer_index(state, config)
assert proposer_index
current_epoch = state.current_epoch(config.SLOTS_PER_EPOCH)
domain_type = signature_domain_to_domain_type(
SignatureDomain.DOMAIN_BEACON_PROPOSER)
seed = hash_eth2(
get_seed(state, current_epoch, domain_type, config) +
state.slot.to_bytes(8, "little"))
random_byte = hash_eth2(seed +
(proposer_index //
32).to_bytes(8, "little"))[proposer_index %
32]
# Verify if proposer_index matches the condition.
assert (state.validators[proposer_index].effective_balance *
MAX_RANDOM_BYTE >= config.MAX_EFFECTIVE_BALANCE * random_byte)
def get_beacon_committee(
state: BeaconState, slot: Slot, index: CommitteeIndex,
config: CommitteeConfig) -> Tuple[ValidatorIndex, ...]:
epoch = compute_epoch_at_slot(slot, config.SLOTS_PER_EPOCH)
committees_per_slot = get_committee_count_at_slot(
state,
slot,
config.MAX_COMMITTEES_PER_SLOT,
config.SLOTS_PER_EPOCH,
config.TARGET_COMMITTEE_SIZE,
)
active_validator_indices = get_active_validator_indices(
state.validators, epoch)
domain_type = signature_domain_to_domain_type(
SignatureDomain.DOMAIN_BEACON_ATTESTER)
return _compute_committee(
indices=active_validator_indices,
seed=get_seed(state, epoch, domain_type, config),
index=(slot % config.SLOTS_PER_EPOCH) * committees_per_slot + index,
count=committees_per_slot * config.SLOTS_PER_EPOCH,
shuffle_round_count=config.SHUFFLE_ROUND_COUNT,
)
def get_beacon_proposer_index(state: BeaconState,
config: Eth2Config) -> ValidatorIndex:
"""
Return the current beacon proposer index.
"""
current_epoch = state.current_epoch(config.SLOTS_PER_EPOCH)
domain_type = signature_domain_to_domain_type(
SignatureDomain.DOMAIN_BEACON_PROPOSER)
seed = hash_eth2(
get_seed(state, current_epoch, domain_type, config) +
state.slot.to_bytes(8, "little"))
indices = get_active_validator_indices(state.validators, current_epoch)
return compute_proposer_index(
state.validators,
indices,
seed,
config.MAX_EFFECTIVE_BALANCE,
config.SHUFFLE_ROUND_COUNT,
)
def get_crosslink_committee(
state: BeaconState, epoch: Epoch, shard: Shard,
config: CommitteeConfig) -> Iterable[ValidatorIndex]:
target_shard = (shard + config.SHARD_COUNT -
get_start_shard(state, epoch, config)) % config.SHARD_COUNT
active_validator_indices = get_active_validator_indices(
state.validators, epoch)
return _compute_committee(
indices=active_validator_indices,
seed=get_seed(state, epoch, config),
index=target_shard,
count=get_committee_count(
len(active_validator_indices),
config.SHARD_COUNT,
config.SLOTS_PER_EPOCH,
config.TARGET_COMMITTEE_SIZE,
),
shuffle_round_count=config.SHUFFLE_ROUND_COUNT,
)
def get_beacon_proposer_index(
state: BeaconState,
committee_config: CommitteeConfig) -> ValidatorIndex:
"""
Return the current beacon proposer index.
"""
first_committee = _calculate_first_committee_at_slot(
state, state.slot, committee_config)
current_epoch = state.current_epoch(committee_config.SLOTS_PER_EPOCH)
seed = get_seed(state, current_epoch, committee_config)
return _find_proposer_in_committee(
state.validators,
first_committee,
current_epoch,
seed,
committee_config.MAX_EFFECTIVE_BALANCE,
)
