def get_crosslink_committees_at_slot(
state: 'BeaconState', slot: SlotNumber, genesis_epoch: EpochNumber,
epoch_length: int, target_committee_size: int, shard_count: int
) -> Iterable[Tuple[Iterable[ValidatorIndex], ShardNumber]]:
"""
Return the list of ``(committee, shard)`` tuples for the ``slot``.
"""
epoch = slot_to_epoch(slot, epoch_length)
current_epoch = state.current_epoch(epoch_length)
validate_epoch_for_current_epoch(
current_epoch=current_epoch,
given_epoch=epoch,
genesis_epoch=genesis_epoch,
epoch_length=epoch_length,
)
# TODO: need to update according to https://github.com/ethereum/eth2.0-specs/pull/520
if epoch < current_epoch:
committees_per_epoch = get_previous_epoch_committee_count(
state=state,
shard_count=shard_count,
epoch_length=epoch_length,
target_committee_size=target_committee_size,
)
seed = state.previous_epoch_seed
shuffling_epoch = state.previous_calculation_epoch
shuffling_start_shard = state.previous_epoch_start_shard
else:
committees_per_epoch = get_current_epoch_committee_count(
state=state,
shard_count=shard_count,
epoch_length=epoch_length,
target_committee_size=target_committee_size,
)
seed = state.current_epoch_seed
shuffling_epoch = state.current_calculation_epoch
shuffling_start_shard = state.current_epoch_start_shard
shuffling = get_shuffling(
seed=seed,
validators=state.validator_registry,
epoch=shuffling_epoch,
epoch_length=epoch_length,
target_committee_size=target_committee_size,
shard_count=shard_count,
)
offset = slot % epoch_length
committees_per_slot = committees_per_epoch // epoch_length
slot_start_shard = (shuffling_start_shard +
committees_per_slot * offset) % shard_count
for index in range(committees_per_slot):
committee = shuffling[committees_per_slot * offset + index]
yield (
committee,
ShardNumber((slot_start_shard + index) % shard_count),
)
def get_crosslink_committees_at_slot(
state: 'BeaconState', slot: SlotNumber, epoch_length: int,
target_committee_size: int, shard_count: int
) -> Iterable[Tuple[Iterable[ValidatorIndex], ShardNumber]]:
"""
Return the list of ``(committee, shard)`` tuples for the ``slot``.
"""
validate_slot_for_state_slot(
state_slot=state.slot,
slot=slot,
epoch_length=epoch_length,
)
state_epoch_slot = state.slot - (state.slot % epoch_length)
offset = slot % epoch_length
if slot < state_epoch_slot:
committees_per_slot = get_previous_epoch_committee_count_per_slot(
state,
shard_count=shard_count,
epoch_length=epoch_length,
target_committee_size=target_committee_size,
)
seed = state.previous_epoch_randao_mix
shuffling_slot = state.previous_epoch_calculation_slot
shuffling_start_shard = state.previous_epoch_start_shard
else:
committees_per_slot = get_current_epoch_committee_count_per_slot(
state,
shard_count=shard_count,
epoch_length=epoch_length,
target_committee_size=target_committee_size,
)
seed = state.current_epoch_randao_mix
shuffling_slot = state.current_epoch_calculation_slot
shuffling_start_shard = state.current_epoch_start_shard
offset = slot % epoch_length
shuffling = get_shuffling(
seed=seed,
validators=state.validator_registry,
slot=shuffling_slot,
epoch_length=epoch_length,
target_committee_size=target_committee_size,
shard_count=shard_count,
)
slot_start_shard = (shuffling_start_shard +
committees_per_slot * offset) % shard_count
for index in range(committees_per_slot):
committee = shuffling[committees_per_slot * offset + index]
yield (
committee,
ShardNumber((slot_start_shard + index) % shard_count),
)
def _get_shards_committees_for_shard_indices(
shard_indices: Sequence[Sequence[ValidatorIndex]],
start_shard: ShardNumber, total_validator_count: int,
shard_count: int) -> Iterable[ShardCommittee]:
"""
Return filled [ShardCommittee] tuple.
"""
for index, indices in enumerate(shard_indices):
yield ShardCommittee(
shard=ShardNumber((start_shard + index) % shard_count),
committee=indices,
total_validator_count=total_validator_count,
)
def get_crosslink_committees_at_slot(
state: 'BeaconState',
slot: SlotNumber,
committee_config: CommitteeConfig,
registry_change: bool = False
) -> Iterable[Tuple[Iterable[ValidatorIndex], ShardNumber]]:
"""
Return the list of ``(committee, shard)`` tuples for the ``slot``.
"""
genesis_epoch = committee_config.GENESIS_EPOCH
shard_count = committee_config.SHARD_COUNT
epoch_length = committee_config.EPOCH_LENGTH
target_committee_size = committee_config.TARGET_COMMITTEE_SIZE
seed_lookahead = committee_config.SEED_LOOKAHEAD
entry_exit_delay = committee_config.ENTRY_EXIT_DELAY
latest_index_roots_length = committee_config.LATEST_INDEX_ROOTS_LENGTH
latest_randao_mixes_length = committee_config.LATEST_RANDAO_MIXES_LENGTH
epoch = slot_to_epoch(slot, epoch_length)
current_epoch = state.current_epoch(epoch_length)
previous_epoch = state.previous_epoch(epoch_length, genesis_epoch)
next_epoch = state.next_epoch(epoch_length)
validate_epoch_for_current_epoch(
current_epoch=current_epoch,
given_epoch=epoch,
genesis_epoch=genesis_epoch,
)
if epoch == previous_epoch:
committees_per_epoch = get_previous_epoch_committee_count(
state=state,
shard_count=shard_count,
epoch_length=epoch_length,
target_committee_size=target_committee_size,
)
seed = state.previous_epoch_seed
shuffling_epoch = state.previous_calculation_epoch
shuffling_start_shard = state.previous_epoch_start_shard
elif epoch == current_epoch:
committees_per_epoch = get_current_epoch_committee_count(
state=state,
shard_count=shard_count,
epoch_length=epoch_length,
target_committee_size=target_committee_size,
)
seed = state.current_epoch_seed
shuffling_epoch = state.current_calculation_epoch
shuffling_start_shard = state.current_epoch_start_shard
elif epoch == next_epoch:
current_committees_per_epoch = get_current_epoch_committee_count(
state=state,
shard_count=shard_count,
epoch_length=epoch_length,
target_committee_size=target_committee_size,
)
committees_per_epoch = get_next_epoch_committee_count(
state=state,
shard_count=shard_count,
epoch_length=epoch_length,
target_committee_size=target_committee_size,
)
shuffling_epoch = next_epoch
epochs_since_last_registry_update = current_epoch - state.validator_registry_update_epoch
should_reseed = (epochs_since_last_registry_update > 1 and
is_power_of_two(epochs_since_last_registry_update))
if registry_change:
# for mocking this out in tests.
seed = helpers.generate_seed(
state=state,
epoch=next_epoch,
epoch_length=epoch_length,
seed_lookahead=seed_lookahead,
entry_exit_delay=entry_exit_delay,
latest_index_roots_length=latest_index_roots_length,
latest_randao_mixes_length=latest_randao_mixes_length,
)
shuffling_start_shard = (
state.current_epoch_start_shard +
current_committees_per_epoch) % shard_count
elif should_reseed:
# for mocking this out in tests.
seed = helpers.generate_seed(
state=state,
epoch=next_epoch,
epoch_length=epoch_length,
seed_lookahead=seed_lookahead,
entry_exit_delay=entry_exit_delay,
latest_index_roots_length=latest_index_roots_length,
latest_randao_mixes_length=latest_randao_mixes_length,
)
shuffling_start_shard = state.current_epoch_start_shard
else:
seed = state.current_epoch_seed
shuffling_start_shard = state.current_epoch_start_shard
shuffling = get_shuffling(
seed=seed,
validators=state.validator_registry,
epoch=shuffling_epoch,
epoch_length=epoch_length,
target_committee_size=target_committee_size,
shard_count=shard_count,
)
offset = slot % epoch_length
committees_per_slot = committees_per_epoch // epoch_length
slot_start_shard = (shuffling_start_shard +
committees_per_slot * offset) % shard_count
for index in range(committees_per_slot):
committee = shuffling[committees_per_slot * offset + index]
yield (
committee,
ShardNumber((slot_start_shard + index) % shard_count),
)
ZERO_ADDRESS, )
from eth2.beacon.state_machines.configs import BeaconConfig
from eth2.beacon.typing import (
SlotNumber,
ShardNumber,
Ether,
Second,
)
SERENITY_CONFIG = BeaconConfig(
# Misc
SHARD_COUNT=2**10, # (= 1,024) shards
TARGET_COMMITTEE_SIZE=2**7, # (= 128) validators
EJECTION_BALANCE=Ether(2**4), # (= 16) ETH
MAX_BALANCE_CHURN_QUOTIENT=2**5, # (= 32)
BEACON_CHAIN_SHARD_NUMBER=ShardNumber(2**64 - 1),
MAX_CASPER_VOTES=2**10, # (= 1,024) votes
LATEST_BLOCK_ROOTS_LENGTH=2**13, # (= 8,192) block roots
LATEST_RANDAO_MIXES_LENGTH=2**13, # (= 8,192) randao mixes
LATEST_PENALIZED_EXIT_LENGTH=2**13, # (= 8,192) randao mixes
# Deposit contract
DEPOSIT_CONTRACT_ADDRESS=ZERO_ADDRESS, # TBD
DEPOSIT_CONTRACT_TREE_DEPTH=2**5, # (= 32)
MIN_DEPOSIT=Ether(2**0), # (= 1) ETH
MAX_DEPOSIT=Ether(2**5), # (= 32) ETH
# Initial values
GENESIS_FORK_VERSION=0,
GENESIS_SLOT=SlotNumber(0),
GENESIS_START_SHARD=ShardNumber(0),
BLS_WITHDRAWAL_PREFIX_BYTE=b'\x00',
# Time parameters
ZERO_ADDRESS, )
from eth2.beacon.state_machines.configs import BeaconConfig
from eth2.beacon.typing import (
SlotNumber,
ShardNumber,
Ether,
Second,
)
SERENITY_CONFIG = BeaconConfig(
# Misc
SHARD_COUNT=2**10, # (= 1,024) shards
TARGET_COMMITTEE_SIZE=2**7, # (= 128) validators
EJECTION_BALANCE=Ether(2**4), # (= 16) ETH
MAX_BALANCE_CHURN_QUOTIENT=2**5, # (= 32)
BEACON_CHAIN_SHARD_NUMBER=ShardNumber(2**64 - 1),
MAX_CASPER_VOTES=2**10, # (= 1,024) votes
LATEST_BLOCK_ROOTS_LENGTH=2**13, # (= 8,192) block roots
LATEST_RANDAO_MIXES_LENGTH=2**13, # (= 8,192) randao mixes
LATEST_PENALIZED_EXIT_LENGTH=2**13, # (= 8,192) randao mixes
# Deposit contract
DEPOSIT_CONTRACT_ADDRESS=ZERO_ADDRESS, # TBD
DEPOSIT_CONTRACT_TREE_DEPTH=2**5, # (= 32)
MIN_DEPOSIT=Ether(2**0), # (= 1) ETH
MAX_DEPOSIT=Ether(2**5), # (= 32) ETH
# Initial values
GENESIS_FORK_VERSION=0,
GENESIS_SLOT=SlotNumber(0),
BLS_WITHDRAWAL_PREFIX_BYTE=b'\x00',
# Time parameters
SLOT_DURATION=Second(6), # seconds