def fill_recent_block_hashes(active_state, parent_block, block):
return ActiveState(
pending_attestations=deepcopy(active_state.pending_attestations),
recent_block_hashes=get_new_recent_block_hashes(
active_state.recent_block_hashes, parent_block.slot_number,
block.slot_number, block.parent_hash),
block_vote_cache=deepcopy(active_state.block_vote_cache))
def get_updated_block_vote_cache(crystallized_state, active_state, attestation,
block, block_vote_cache, config):
new_block_vote_cache = deepcopy(block_vote_cache)
parent_hashes = get_signed_parent_hashes(active_state, block, attestation,
config)
attestation_indices = get_attestation_indices(crystallized_state,
attestation, config)
for parent_hash in parent_hashes:
if parent_hash in attestation.oblique_parent_hashes:
continue
if parent_hash not in new_block_vote_cache:
new_block_vote_cache[parent_hash] = {
'voter_indices': set(),
'total_voter_deposits': 0
}
for i, index in enumerate(attestation_indices):
if (has_voted(attestation.attester_bitfield, i) and index
not in new_block_vote_cache[parent_hash]['voter_indices']):
new_block_vote_cache[parent_hash]['voter_indices'].add(index)
new_block_vote_cache[parent_hash][
'total_voter_deposits'] += crystallized_state.validators[
index].balance
return new_block_vote_cache
def process_updated_crosslinks(crystallized_state,
active_state,
config=DEFAULT_CONFIG):
total_attestation_balance = {}
crosslinks = deepcopy(crystallized_state.crosslink_records)
for attestation in active_state.pending_attestations:
shard_tuple = (attestation.shard_id, attestation.shard_block_hash)
if shard_tuple not in total_attestation_balance:
total_attestation_balance[shard_tuple] = 0
attestation_indices = get_attestation_indices(crystallized_state,
attestation, config)
# find total committee size by balance
total_committee_balance = sum([
crystallized_state.validators[index].balance
for index in attestation_indices
])
# find votes cast in attestation by balance
total_attestation_balance[shard_tuple] += sum([
crystallized_state.validators[index].balance
for in_cycle_slot_height, index in enumerate(attestation_indices)
if has_voted(attestation.attester_bitfield, in_cycle_slot_height)
])
# if 2/3 of committee voted on crosslink and do no yet have crosslink
# for this shard, for this dynasty, add updated crosslink
if (3 * total_attestation_balance[shard_tuple] >=
2 * total_committee_balance
and crystallized_state.current_dynasty >
crosslinks[attestation.shard_id].dynasty):
crosslinks[attestation.shard_id] = CrosslinkRecord(
dynasty=crystallized_state.current_dynasty,
hash=attestation.shard_block_hash)
return crosslinks
def process_block(crystallized_state: CrystallizedState,
active_state: ActiveState,
block: 'Block',
config: dict = DEFAULT_CONFIG) -> ActiveState:
new_block_vote_cache = deepcopy(active_state.block_vote_cache)
for attestation in block.attestations:
validate_attestation(crystallized_state,
active_state,
attestation,
block,
config)
new_block_vote_cache = get_updated_block_vote_cache(
crystallized_state,
active_state,
attestation,
block,
new_block_vote_cache,
config
)
new_attestations = active_state.pending_attestations + block.attestations
new_active_state = ActiveState(
pending_attestations=new_attestations,
recent_block_hashes=active_state.recent_block_hashes[:],
block_vote_cache=new_block_vote_cache
)
return new_active_state
def initialize_new_cycle(crystallized_state,
active_state,
block,
config=DEFAULT_CONFIG):
cycle_length = config['cycle_length']
last_state_recalc = crystallized_state.last_state_recalc
last_justified_slot = crystallized_state.last_justified_slot
last_finalized_slot = crystallized_state.last_finalized_slot
justified_streak = crystallized_state.justified_streak
# walk through slots last_state_recalc - CYCLE_LENGTH ... last_state_recalc - 1
# and check for justification, streaks, and finality
for i in range(cycle_length):
slot = i + (last_state_recalc - cycle_length)
block_hash = active_state.recent_block_hashes[i]
if block_hash in active_state.block_vote_cache:
vote_balance = active_state.block_vote_cache[block_hash][
'total_voter_deposits']
else:
vote_balance = 0
if 3 * vote_balance >= 2 * crystallized_state.total_deposits:
last_justified_slot = max(last_justified_slot, slot)
justified_streak += 1
else:
justified_streak = 0
if justified_streak >= cycle_length + 1:
last_finalized_slot = max(last_finalized_slot,
slot - cycle_length - 1)
crosslink_records = process_updated_crosslinks(crystallized_state,
active_state, config)
# remove attestations older than last_state_recalc
pending_attestations = [
a for a in active_state.pending_attestations
if a.slot >= last_state_recalc
]
dynasty = crystallized_state.current_dynasty # STUB
dynasty_seed = crystallized_state.dynasty_seed # STUB
dynasty_seed_last_reset = crystallized_state.dynasty_seed_last_reset # STUB
crosslinking_start_shard = 0 # stub. Needs to see where this epoch left off
validators = deepcopy(crystallized_state.validators) # STUB
indices_for_heights = (
crystallized_state.indices_for_heights[cycle_length:] +
# this is a stub and will be addressed by shuffling at dynasty change
crystallized_state.indices_for_heights[cycle_length:])
active_validator_indices = get_active_validator_indices(
dynasty, validators)
new_crystallized_state = CrystallizedState(
validators=validators,
last_state_recalc=last_state_recalc + cycle_length,
indices_for_heights=indices_for_heights,
last_justified_slot=last_justified_slot,
justified_streak=justified_streak,
last_finalized_slot=last_finalized_slot,
current_dynasty=crystallized_state.current_dynasty,
crosslinking_start_shard=crosslinking_start_shard,
crosslink_records=crosslink_records,
total_deposits=sum(
map(lambda i: validators[i].balance, active_validator_indices)),
dynasty_seed=dynasty_seed,
dynasty_seed_last_reset=dynasty_seed_last_reset)
new_active_state = ActiveState(
pending_attestations=pending_attestations,
recent_block_hashes=active_state.recent_block_hashes[:],
# Should probably clean up block_vote_cache but old records won't break cache
# so okay for now
block_vote_cache=deepcopy(active_state.block_vote_cache))
return new_crystallized_state, new_active_state
def _initialize_new_epoch(crystallized_state, active_state):
print('Processing epoch transition')
# Process rewards from FFG/crosslink votes
new_validator_records = deepcopy(crystallized_state.active_validators)
# Who voted in the last epoch
ffg_voter_bitfield = bytearray(active_state.ffg_voter_bitfield)
# Balance changes, and total vote counts for FFG
deltas1, total_vote_count, total_vote_deposits, justify, finalize = \
process_ffg_deposits(crystallized_state, ffg_voter_bitfield)
# Balance changes, and total vote counts for crosslinks
deltas2, new_crosslink_records = process_crosslinks(
crystallized_state, active_state.partial_crosslinks)
# Process other balance deltas
deltas3 = process_balance_deltas(crystallized_state,
active_state.balance_deltas)
for i, v in enumerate(new_validator_records):
v.balance += deltas1[i] + deltas2[i] + deltas3[i]
total_deposits = crystallized_state.total_deposits + sum(deltas1 +
deltas2 + deltas3)
print('New total deposits: %d' % total_deposits)
if justify:
last_justified_epoch = crystallized_state.current_epoch
else:
last_justified_epoch = crystallized_state.last_justified_epoch
if finalize:
last_finalized_epoch = crystallized_state.current_epoch - 1
dynasty = crystallized_state.dynasty + 1
new_queued_validators, new_active_validators, new_exited_validators = \
get_incremented_validator_sets(crystallized_state, new_validator_records)
else:
last_finalized_epoch = crystallized_state.last_finalized_epoch
dynasty = crystallized_state.dynasty
new_queued_validators = crystallized_state.queued_validators
new_active_validators = crystallized_state.active_validators
new_exited_validators = crystallized_state.exited_validators
crystallized_state = CrystallizedState(
queued_validators=new_queued_validators,
active_validators=new_active_validators,
exited_validators=new_exited_validators,
current_shuffling=get_shuffling(active_state.randao,
len(new_active_validators)),
last_justified_epoch=last_justified_epoch,
last_finalized_epoch=last_finalized_epoch,
dynasty=dynasty,
next_shard=0,
current_epoch=crystallized_state.current_epoch + 1,
crosslink_records=new_crosslink_records,
total_deposits=total_deposits)
# Reset the active state
active_state = ActiveState(
height=active_state.height,
randao=active_state.randao,
ffg_voter_bitfield=bytearray(
(len(crystallized_state.active_validators) + 7) // 8),
balance_deltas=[],
partial_crosslinks=[],
total_skip_count=active_state.total_skip_count)
return crystallized_state, active_state
def _initialize_new_epoch(crystallized_state,
active_state,
config=DEFAULT_CONFIG):
print('Processing epoch transition')
# Process rewards from FFG/crosslink votes
new_validator_records = deepcopy(crystallized_state.active_validators)
# Who voted in the last epoch
ffg_voter_bitfield = active_state.ffg_voter_bitfield
# Balance changes, and total vote counts for FFG
deltas_casper, total_vote_count, total_vote_deposits, justify, finalize = \
process_ffg_deposits(crystallized_state, ffg_voter_bitfield)
# Balance changes, and total vote counts for crosslinks
deltas_crosslinks, new_crosslink_records = process_crosslinks(
crystallized_state,
active_state.partial_crosslinks,
config=config,
)
# process recent attesters balance deltas
deltas_recent_attesters = process_recent_attesters(
crystallized_state,
active_state.recent_attesters,
config=config,
)
# process recent proposers balance deltas
deltas_recent_proposers = process_recent_proposers(
crystallized_state, active_state.recent_proposers)
for i, validator in enumerate(new_validator_records):
validator.balance += (deltas_casper[i] + deltas_crosslinks[i] +
deltas_recent_attesters[i] +
deltas_recent_proposers[i])
total_deposits = crystallized_state.total_deposits + sum(
deltas_casper + deltas_crosslinks + deltas_recent_attesters +
deltas_recent_proposers)
print('New total deposits: %d' % total_deposits)
if justify:
last_justified_epoch = crystallized_state.current_epoch
else:
last_justified_epoch = crystallized_state.last_justified_epoch
if finalize:
last_finalized_epoch = crystallized_state.current_epoch - 1
dynasty = crystallized_state.dynasty + 1
new_queued_validators, new_active_validators, new_exited_validators = \
get_incremented_validator_sets(crystallized_state, new_validator_records)
else:
last_finalized_epoch = crystallized_state.last_finalized_epoch
dynasty = crystallized_state.dynasty
new_queued_validators = crystallized_state.queued_validators
new_active_validators = crystallized_state.active_validators
new_exited_validators = crystallized_state.exited_validators
crystallized_state = CrystallizedState(
queued_validators=new_queued_validators,
active_validators=new_active_validators,
exited_validators=new_exited_validators,
current_shuffling=get_shuffling(active_state.randao,
len(new_active_validators),
config=config),
last_justified_epoch=last_justified_epoch,
last_finalized_epoch=last_finalized_epoch,
dynasty=dynasty,
next_shard=0,
current_epoch=crystallized_state.current_epoch + 1,
crosslink_records=new_crosslink_records,
total_deposits=total_deposits)
# Reset the active state
active_state = ActiveState(height=active_state.height,
randao=active_state.randao,
ffg_voter_bitfield=get_empty_bitfield(
crystallized_state.num_active_validators),
balance_deltas=[],
partial_crosslinks=[],
total_skip_count=active_state.total_skip_count,
recent_proposers=[])
return crystallized_state, active_state
