def test_store_get_latest_attestation(genesis_state, genesis_block, config,
collisions_from_another_epoch):
"""
Given some attestations across the various sources, can we
find the latest ones for each validator?
"""
some_epoch = 3
state = genesis_state.set(
"slot", compute_start_slot_at_epoch(some_epoch,
config.SLOTS_PER_EPOCH))
some_time = (_compute_seconds_since_genesis_for_epoch(some_epoch, config) +
state.genesis_time)
previous_epoch = state.previous_epoch(config.SLOTS_PER_EPOCH,
config.GENESIS_EPOCH)
previous_epoch_committee_count = _get_committee_count(
state, previous_epoch, config)
current_epoch = state.current_epoch(config.SLOTS_PER_EPOCH)
current_epoch_committee_count = _get_committee_count(
state, current_epoch, config)
number_of_committee_samples = 4
assert number_of_committee_samples <= previous_epoch_committee_count
assert number_of_committee_samples <= current_epoch_committee_count
block_producer = _mk_block_at_slot(genesis_block)
# prepare samples from previous epoch
previous_epoch_attestations_by_index = _mk_attestations_for_epoch_by_count(
number_of_committee_samples, previous_epoch, block_producer, state,
config)
previous_epoch_attestations = _extract_attestations_from_index_keying(
previous_epoch_attestations_by_index.values())
# prepare samples from current epoch
current_epoch_attestations_by_index = _mk_attestations_for_epoch_by_count(
number_of_committee_samples, current_epoch, block_producer, state,
config)
current_epoch_attestations_by_index = keyfilter(
lambda index: index not in previous_epoch_attestations_by_index,
current_epoch_attestations_by_index,
)
current_epoch_attestations = _extract_attestations_from_index_keying(
current_epoch_attestations_by_index.values())
pool_attestations_by_index = _mk_attestations_for_epoch_by_count(
number_of_committee_samples, current_epoch, block_producer, state,
config)
pool_attestations_by_index = keyfilter(
lambda index: (index not in previous_epoch_attestations_by_index or
index not in current_epoch_attestations_by_index),
pool_attestations_by_index,
)
pool_attestations = _extract_attestations_from_index_keying(
pool_attestations_by_index.values())
all_attestations_by_index = (
previous_epoch_attestations_by_index,
current_epoch_attestations_by_index,
pool_attestations_by_index,
)
if collisions_from_another_epoch:
(
previous_epoch_attestations_by_index,
current_epoch_attestations_by_index,
pool_attestations_by_index,
) = _introduce_collisions(all_attestations_by_index, block_producer,
state, config)
previous_epoch_attestations = _extract_attestations_from_index_keying(
previous_epoch_attestations_by_index.values())
current_epoch_attestations = _extract_attestations_from_index_keying(
current_epoch_attestations_by_index.values())
pool_attestations = _extract_attestations_from_index_keying(
pool_attestations_by_index.values())
# build expected results
expected_index = merge_with(
_keep_by_latest_slot,
previous_epoch_attestations_by_index,
current_epoch_attestations_by_index,
pool_attestations_by_index,
)
chain_db = None # not relevant for this test
context = Context.from_genesis(genesis_state, genesis_block)
context.time = some_time
store = Store(chain_db, SignedBeaconBlock, config, context)
for attestations in (
previous_epoch_attestations,
current_epoch_attestations,
pool_attestations,
):
for attestation in attestations:
# NOTE: we need to synchronize the context w/ chain data used to construct
# attestations above; this synchronization takes advantage of some of the
# internals of ``on_attestation`` to shortcut constructing the complete network
# state needed to test the function of the ``Store``.
block = block_producer(attestation.data.slot)
context.blocks[block.message.hash_tree_root] = block
context.block_states[block.message.hash_tree_root] = genesis_state
store.on_attestation(attestation, validate_signature=False)
# sanity check
assert expected_index.keys() == store._context.latest_messages.keys()
for validator_index in range(len(state.validators)):
expected_attestation_data = expected_index.get(validator_index, None)
target = expected_attestation_data.target
expected_message = LatestMessage(epoch=target.epoch, root=target.root)
stored_message = store._context.latest_messages.get(
validator_index, None)
assert expected_message == stored_message
class SerenityStateMachine(BeaconStateMachine):
# fork name
fork = "serenity" # type: str
config = SERENITY_CONFIG
# classes
block_class = SerenityBeaconBlock # type: Type[BaseBeaconBlock]
signed_block_class = SerenitySignedBeaconBlock
state_class = SerenityBeaconState # type: Type[BeaconState]
state_transition_class = SerenityStateTransition # type: Type[BaseStateTransition]
fork_choice_scoring_class = LMDGHOSTScoring # type: Type[BaseForkChoiceScoring]
def __init__(
self, chaindb: BaseBeaconChainDB, fork_choice_context: LMDGHOSTContext = None
) -> None:
super().__init__(chaindb)
self._fork_choice_store = Store(
chaindb,
self.block_class,
self.config,
fork_choice_context or self._get_fork_choice_context(),
)
self.fork_choice_scoring = LMDGHOSTScoring(self._fork_choice_store)
def _get_fork_choice_context(self) -> LMDGHOSTContext:
try:
fork_choice_context_data = self.chaindb.get_fork_choice_context_data_for(
self.fork
)
except MissingForkChoiceContext:
# NOTE: ``MissingForkChoiceContext`` here implies that we are missing the
# fork choice context for this fork, which happens to be the genesis fork.
# In this situation (possibly uniquely), we want to build a new
# fork choice context from the genesis data.
genesis_root = self.chaindb.get_genesis_block_root()
genesis_block = self.chaindb.get_block_by_root(
genesis_root, self.block_class
)
genesis_state = self.chaindb.get_state_by_root(
genesis_block.message.state_root, self.state_class
)
return LMDGHOSTContext.from_genesis(genesis_state, genesis_block)
else:
return LMDGHOSTContext.from_bytes(fork_choice_context_data)
# methods
def _get_justified_head_state(self) -> BeaconState:
justified_head = self.chaindb.get_justified_head(self.block_class)
return self.chaindb.get_state_by_root(
justified_head.state_root, self.state_class
)
def get_fork_choice_scoring(self) -> BaseForkChoiceScoring:
return self.fork_choice_scoring
def on_tick(self, time: Timestamp) -> None:
self._fork_choice_store.on_tick(time)
def on_block(self, block: BaseBeaconBlock) -> None:
self._fork_choice_store.on_block(block)
def on_attestation(self, attestation: Attestation) -> None:
self._fork_choice_store.on_attestation(attestation)
