lighthouse/validator_client/src/attestation_service.rs
blacktemplar 23a8f31f83 Fix clippy warnings (#1385)
## Issue Addressed

NA

## Proposed Changes

Fixes most clippy warnings and ignores the rest of them, see issue #1388.
2020-07-23 14:18:00 +00:00

580 lines
22 KiB
Rust

use crate::{
duties_service::{DutiesService, DutyAndProof},
validator_store::ValidatorStore,
};
use environment::RuntimeContext;
use futures::StreamExt;
use remote_beacon_node::{PublishStatus, RemoteBeaconNode};
use slog::{crit, debug, error, info, trace};
use slot_clock::SlotClock;
use std::collections::HashMap;
use std::ops::Deref;
use std::sync::Arc;
use tokio::time::{delay_until, interval_at, Duration, Instant};
use types::{Attestation, ChainSpec, CommitteeIndex, EthSpec, Slot, SubnetId};
/// Builds an `AttestationService`.
pub struct AttestationServiceBuilder<T, E: EthSpec> {
duties_service: Option<DutiesService<T, E>>,
validator_store: Option<ValidatorStore<T, E>>,
slot_clock: Option<T>,
beacon_node: Option<RemoteBeaconNode<E>>,
context: Option<RuntimeContext<E>>,
}
impl<T: SlotClock + 'static, E: EthSpec> AttestationServiceBuilder<T, E> {
pub fn new() -> Self {
Self {
duties_service: None,
validator_store: None,
slot_clock: None,
beacon_node: None,
context: None,
}
}
pub fn duties_service(mut self, service: DutiesService<T, E>) -> Self {
self.duties_service = Some(service);
self
}
pub fn validator_store(mut self, store: ValidatorStore<T, E>) -> Self {
self.validator_store = Some(store);
self
}
pub fn slot_clock(mut self, slot_clock: T) -> Self {
self.slot_clock = Some(slot_clock);
self
}
pub fn beacon_node(mut self, beacon_node: RemoteBeaconNode<E>) -> Self {
self.beacon_node = Some(beacon_node);
self
}
pub fn runtime_context(mut self, context: RuntimeContext<E>) -> Self {
self.context = Some(context);
self
}
pub fn build(self) -> Result<AttestationService<T, E>, String> {
Ok(AttestationService {
inner: Arc::new(Inner {
duties_service: self
.duties_service
.ok_or_else(|| "Cannot build AttestationService without duties_service")?,
validator_store: self
.validator_store
.ok_or_else(|| "Cannot build AttestationService without validator_store")?,
slot_clock: self
.slot_clock
.ok_or_else(|| "Cannot build AttestationService without slot_clock")?,
beacon_node: self
.beacon_node
.ok_or_else(|| "Cannot build AttestationService without beacon_node")?,
context: self
.context
.ok_or_else(|| "Cannot build AttestationService without runtime_context")?,
}),
})
}
}
/// Helper to minimise `Arc` usage.
pub struct Inner<T, E: EthSpec> {
duties_service: DutiesService<T, E>,
validator_store: ValidatorStore<T, E>,
slot_clock: T,
beacon_node: RemoteBeaconNode<E>,
context: RuntimeContext<E>,
}
/// Attempts to produce attestations for all known validators 1/3rd of the way through each slot.
///
/// If any validators are on the same committee, a single attestation will be downloaded and
/// returned to the beacon node. This attestation will have a signature from each of the
/// validators.
pub struct AttestationService<T, E: EthSpec> {
inner: Arc<Inner<T, E>>,
}
impl<T, E: EthSpec> Clone for AttestationService<T, E> {
fn clone(&self) -> Self {
Self {
inner: self.inner.clone(),
}
}
}
impl<T, E: EthSpec> Deref for AttestationService<T, E> {
type Target = Inner<T, E>;
fn deref(&self) -> &Self::Target {
self.inner.deref()
}
}
impl<T: SlotClock + 'static, E: EthSpec> AttestationService<T, E> {
/// Starts the service which periodically produces attestations.
pub fn start_update_service(self, spec: &ChainSpec) -> Result<(), String> {
let log = self.context.log().clone();
let slot_duration = Duration::from_millis(spec.milliseconds_per_slot);
let duration_to_next_slot = self
.slot_clock
.duration_to_next_slot()
.ok_or_else(|| "Unable to determine duration to next slot".to_string())?;
info!(
log,
"Attestation production service started";
"next_update_millis" => duration_to_next_slot.as_millis()
);
let mut interval = {
// Note: `interval_at` panics if `slot_duration` is 0
interval_at(
Instant::now() + duration_to_next_slot + slot_duration / 3,
slot_duration,
)
};
let executor = self.context.executor.clone();
let interval_fut = async move {
while interval.next().await.is_some() {
let log = self.context.log();
if let Err(e) = self.spawn_attestation_tasks(slot_duration) {
crit!(
log,
"Failed to spawn attestation tasks";
"error" => e
)
} else {
trace!(
log,
"Spawned attestation tasks";
)
}
}
};
executor.spawn(interval_fut, "attestation_service");
Ok(())
}
/// For each each required attestation, spawn a new task that downloads, signs and uploads the
/// attestation to the beacon node.
fn spawn_attestation_tasks(&self, slot_duration: Duration) -> Result<(), String> {
let slot = self
.slot_clock
.now()
.ok_or_else(|| "Failed to read slot clock".to_string())?;
let duration_to_next_slot = self
.slot_clock
.duration_to_next_slot()
.ok_or_else(|| "Unable to determine duration to next slot".to_string())?;
// If a validator needs to publish an aggregate attestation, they must do so at 2/3
// through the slot. This delay triggers at this time
let aggregate_production_instant = Instant::now()
+ duration_to_next_slot
.checked_sub(slot_duration / 3)
.unwrap_or_else(|| Duration::from_secs(0));
let duties_by_committee_index: HashMap<CommitteeIndex, Vec<DutyAndProof>> = self
.duties_service
.attesters(slot)
.into_iter()
.fold(HashMap::new(), |mut map, duty_and_proof| {
if let Some(committee_index) = duty_and_proof.duty.attestation_committee_index {
let validator_duties = map.entry(committee_index).or_insert_with(Vec::new);
validator_duties.push(duty_and_proof);
}
map
});
// For each committee index for this slot:
//
// - Create and publish an `Attestation` for all required validators.
// - Create and publish `SignedAggregateAndProof` for all aggregating validators.
duties_by_committee_index
.into_iter()
.for_each(|(committee_index, validator_duties)| {
// Spawn a separate task for each attestation.
self.inner.context.executor.runtime_handle().spawn(
self.clone().publish_attestations_and_aggregates(
slot,
committee_index,
validator_duties,
aggregate_production_instant,
),
);
});
Ok(())
}
/// Performs the first step of the attesting process: downloading `Attestation` objects,
/// signing them and returning them to the validator.
///
/// https://github.com/ethereum/eth2.0-specs/blob/v0.12.1/specs/phase0/validator.md#attesting
///
/// ## Detail
///
/// The given `validator_duties` should already be filtered to only contain those that match
/// `slot` and `committee_index`. Critical errors will be logged if this is not the case.
async fn publish_attestations_and_aggregates(
self,
slot: Slot,
committee_index: CommitteeIndex,
validator_duties: Vec<DutyAndProof>,
aggregate_production_instant: Instant,
) -> Result<(), ()> {
let log = self.context.log();
// There's not need to produce `Attestation` or `SignedAggregateAndProof` if we do not have
// any validators for the given `slot` and `committee_index`.
if validator_duties.is_empty() {
return Ok(());
}
// Step 1.
//
// Download, sign and publish an `Attestation` for each validator.
let attestation_opt = self
.produce_and_publish_attestations(slot, committee_index, &validator_duties)
.await
.map_err(move |e| {
crit!(
log,
"Error during attestation routine";
"error" => format!("{:?}", e),
"committee_index" => committee_index,
"slot" => slot.as_u64(),
)
})?;
// Step 2.
//
// If an attestation was produced, make an aggregate.
if let Some(attestation) = attestation_opt {
// First, wait until the `aggregation_production_instant` (2/3rds
// of the way though the slot). As verified in the
// `delay_triggers_when_in_the_past` test, this code will still run
// even if the instant has already elapsed.
delay_until(aggregate_production_instant).await;
// Then download, sign and publish a `SignedAggregateAndProof` for each
// validator that is elected to aggregate for this `slot` and
// `committee_index`.
self.produce_and_publish_aggregates(attestation, &validator_duties)
.await
.map_err(move |e| {
crit!(
log,
"Error during attestation routine";
"error" => format!("{:?}", e),
"committee_index" => committee_index,
"slot" => slot.as_u64(),
)
})?;
}
Ok(())
}
/// Performs the first step of the attesting process: downloading `Attestation` objects,
/// signing them and returning them to the validator.
///
/// https://github.com/ethereum/eth2.0-specs/blob/v0.12.1/specs/phase0/validator.md#attesting
///
/// ## Detail
///
/// The given `validator_duties` should already be filtered to only contain those that match
/// `slot` and `committee_index`. Critical errors will be logged if this is not the case.
///
/// Only one `Attestation` is downloaded from the BN. It is then cloned and signed by each
/// validator and the list of individually-signed `Attestation` objects is returned to the BN.
async fn produce_and_publish_attestations(
&self,
slot: Slot,
committee_index: CommitteeIndex,
validator_duties: &[DutyAndProof],
) -> Result<Option<Attestation<E>>, String> {
let log = self.context.log();
if validator_duties.is_empty() {
return Ok(None);
}
let current_epoch = self
.slot_clock
.now()
.ok_or_else(|| "Unable to determine current slot from clock".to_string())?
.epoch(E::slots_per_epoch());
let attestation = self
.beacon_node
.http
.validator()
.produce_attestation(slot, committee_index)
.await
.map_err(|e| format!("Failed to produce attestation: {:?}", e))?;
// For each validator in `validator_duties`, clone the `attestation` and add
// their signature.
//
// If any validator is unable to sign, they are simply skipped.
let signed_attestations = validator_duties
.iter()
.filter_map(|duty| {
// Ensure that all required fields are present in the validator duty.
let (
duty_slot,
duty_committee_index,
validator_committee_position,
_,
committee_count_at_slot,
) = if let Some(tuple) = duty.attestation_duties() {
tuple
} else {
crit!(
log,
"Missing validator duties when signing";
"duties" => format!("{:?}", duty)
);
return None;
};
// Ensure that the attestation matches the duties.
if duty_slot != attestation.data.slot
|| duty_committee_index != attestation.data.index
{
crit!(
log,
"Inconsistent validator duties during signing";
"validator" => format!("{:?}", duty.validator_pubkey()),
"duty_slot" => duty_slot,
"attestation_slot" => attestation.data.slot,
"duty_index" => duty_committee_index,
"attestation_index" => attestation.data.index,
);
return None;
}
let mut attestation = attestation.clone();
let subnet_id = SubnetId::compute_subnet_for_attestation_data::<E>(
&attestation.data,
committee_count_at_slot,
&self.context.eth2_config().spec,
)
.map_err(|e| {
error!(
log,
"Failed to compute subnet id to publish attestation: {:?}", e
)
})
.ok()?;
self.validator_store
.sign_attestation(
duty.validator_pubkey(),
validator_committee_position,
&mut attestation,
current_epoch,
)
.map(|_| (attestation, subnet_id))
})
.collect::<Vec<_>>();
// If there are any signed attestations, publish them to the BN. Otherwise,
// just return early.
if let Some(attestation) = signed_attestations.first().cloned() {
let num_attestations = signed_attestations.len();
let beacon_block_root = attestation.0.data.beacon_block_root;
self.beacon_node
.http
.validator()
.publish_attestations(signed_attestations)
.await
.map_err(|e| format!("Failed to publish attestation: {:?}", e))
.map(move |publish_status| match publish_status {
PublishStatus::Valid => info!(
log,
"Successfully published attestations";
"count" => num_attestations,
"head_block" => format!("{:?}", beacon_block_root),
"committee_index" => committee_index,
"slot" => slot.as_u64(),
"type" => "unaggregated",
),
PublishStatus::Invalid(msg) => crit!(
log,
"Published attestation was invalid";
"message" => msg,
"committee_index" => committee_index,
"slot" => slot.as_u64(),
"type" => "unaggregated",
),
PublishStatus::Unknown => {
crit!(log, "Unknown condition when publishing unagg. attestation")
}
})
.map(|()| Some(attestation.0))
} else {
debug!(
log,
"No attestations to publish";
"committee_index" => committee_index,
"slot" => slot.as_u64(),
);
Ok(None)
}
}
/// Performs the second step of the attesting process: downloading an aggregated `Attestation`,
/// converting it into a `SignedAggregateAndProof` and returning it to the BN.
///
/// https://github.com/ethereum/eth2.0-specs/blob/v0.12.1/specs/phase0/validator.md#broadcast-aggregate
///
/// ## Detail
///
/// The given `validator_duties` should already be filtered to only contain those that match
/// `slot` and `committee_index`. Critical errors will be logged if this is not the case.
///
/// Only one aggregated `Attestation` is downloaded from the BN. It is then cloned and signed
/// by each validator and the list of individually-signed `SignedAggregateAndProof` objects is
/// returned to the BN.
async fn produce_and_publish_aggregates(
&self,
attestation: Attestation<E>,
validator_duties: &[DutyAndProof],
) -> Result<(), String> {
let log = self.context.log();
let aggregated_attestation = self
.beacon_node
.http
.validator()
.produce_aggregate_attestation(&attestation.data)
.await
.map_err(|e| format!("Failed to produce an aggregate attestation: {:?}", e))?;
// For each validator, clone the `aggregated_attestation` and convert it into
// a `SignedAggregateAndProof`
let signed_aggregate_and_proofs = validator_duties
.iter()
.filter_map(|duty_and_proof| {
// Do not produce a signed aggregator for validators that are not
// subscribed aggregators.
let selection_proof = duty_and_proof.selection_proof.as_ref()?.clone();
let (duty_slot, duty_committee_index, _, validator_index, _) =
duty_and_proof.attestation_duties().or_else(|| {
crit!(log, "Missing duties when signing aggregate");
None
})?;
let pubkey = &duty_and_proof.duty.validator_pubkey;
let slot = attestation.data.slot;
let committee_index = attestation.data.index;
if duty_slot != slot || duty_committee_index != committee_index {
crit!(log, "Inconsistent validator duties during signing");
return None;
}
if let Some(signed_aggregate_and_proof) =
self.validator_store.produce_signed_aggregate_and_proof(
pubkey,
validator_index,
aggregated_attestation.clone(),
selection_proof,
)
{
Some(signed_aggregate_and_proof)
} else {
crit!(log, "Failed to sign attestation");
None
}
})
.collect::<Vec<_>>();
// If there any signed aggregates and proofs were produced, publish them to the
// BN.
if let Some(first) = signed_aggregate_and_proofs.first().cloned() {
let attestation = first.message.aggregate;
let publish_status = self
.beacon_node
.http
.validator()
.publish_aggregate_and_proof(signed_aggregate_and_proofs)
.await
.map_err(|e| format!("Failed to publish aggregate and proofs: {:?}", e))?;
match publish_status {
PublishStatus::Valid => info!(
log,
"Successfully published attestations";
"signatures" => attestation.aggregation_bits.num_set_bits(),
"head_block" => format!("{:?}", attestation.data.beacon_block_root),
"committee_index" => attestation.data.index,
"slot" => attestation.data.slot.as_u64(),
"type" => "aggregated",
),
PublishStatus::Invalid(msg) => crit!(
log,
"Published attestation was invalid";
"message" => msg,
"committee_index" => attestation.data.index,
"slot" => attestation.data.slot.as_u64(),
"type" => "aggregated",
),
PublishStatus::Unknown => {
crit!(log, "Unknown condition when publishing agg. attestation")
}
};
Ok(())
} else {
debug!(
log,
"No signed aggregates to publish";
"committee_index" => attestation.data.index,
"slot" => attestation.data.slot.as_u64(),
);
Ok(())
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use futures::future::FutureExt;
use parking_lot::RwLock;
/// This test is to ensure that a `tokio_timer::Delay` with an instant in the past will still
/// trigger.
#[tokio::test]
async fn delay_triggers_when_in_the_past() {
let in_the_past = Instant::now() - Duration::from_secs(2);
let state_1 = Arc::new(RwLock::new(in_the_past));
let state_2 = state_1.clone();
delay_until(in_the_past)
.map(move |()| *state_1.write() = Instant::now())
.await;
assert!(
*state_2.read() > in_the_past,
"state should have been updated"
);
}
}