prysm-pulse/beacon-chain/archiver/service.go
terence tsao 26da7c4114 Nil state fallback in Blockchain.HeadState() (#4042)
* Can build

* All tests pass

* Update beacon-chain/blockchain/chain_info.go

* Fix context
2019-11-19 10:12:50 -06:00

182 lines
6.3 KiB
Go

package archiver
import (
"context"
"fmt"
"github.com/pkg/errors"
"github.com/prysmaticlabs/prysm/beacon-chain/blockchain"
"github.com/prysmaticlabs/prysm/beacon-chain/core/epoch"
"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
"github.com/prysmaticlabs/prysm/beacon-chain/core/statefeed"
"github.com/prysmaticlabs/prysm/beacon-chain/core/validators"
"github.com/prysmaticlabs/prysm/beacon-chain/db"
pb "github.com/prysmaticlabs/prysm/proto/beacon/p2p/v1"
ethpb "github.com/prysmaticlabs/prysm/proto/eth/v1alpha1"
"github.com/prysmaticlabs/prysm/shared/params"
"github.com/sirupsen/logrus"
)
var log = logrus.WithField("prefix", "archiver")
// Service defining archiver functionality for persisting checkpointed
// beacon chain information to a database backend for historical purposes.
type Service struct {
ctx context.Context
cancel context.CancelFunc
beaconDB db.Database
headFetcher blockchain.HeadFetcher
stateNotifier blockchain.StateNotifier
}
// Config options for the archiver service.
type Config struct {
BeaconDB db.Database
HeadFetcher blockchain.HeadFetcher
StateNotifier blockchain.StateNotifier
}
// NewArchiverService initializes the service from configuration options.
func NewArchiverService(ctx context.Context, cfg *Config) *Service {
ctx, cancel := context.WithCancel(ctx)
return &Service{
ctx: ctx,
cancel: cancel,
beaconDB: cfg.BeaconDB,
headFetcher: cfg.HeadFetcher,
stateNotifier: cfg.StateNotifier,
}
}
// Start the archiver service event loop.
func (s *Service) Start() {
go s.run(s.ctx)
}
// Stop the archiver service event loop.
func (s *Service) Stop() error {
defer s.cancel()
return nil
}
// Status reports the healthy status of the archiver. Returning nil means service
// is correctly running without error.
func (s *Service) Status() error {
return nil
}
// We archive committee information pertaining to the head state's epoch.
func (s *Service) archiveCommitteeInfo(ctx context.Context, headState *pb.BeaconState) error {
currentEpoch := helpers.SlotToEpoch(headState.Slot)
proposerSeed, err := helpers.Seed(headState, currentEpoch, params.BeaconConfig().DomainBeaconProposer)
if err != nil {
return errors.Wrap(err, "could not generate seed")
}
attesterSeed, err := helpers.Seed(headState, currentEpoch, params.BeaconConfig().DomainBeaconAttester)
if err != nil {
return errors.Wrap(err, "could not generate seed")
}
info := &ethpb.ArchivedCommitteeInfo{
ProposerSeed: proposerSeed[:],
AttesterSeed: attesterSeed[:],
}
if err := s.beaconDB.SaveArchivedCommitteeInfo(ctx, currentEpoch, info); err != nil {
return errors.Wrap(err, "could not archive committee info")
}
return nil
}
// We archive active validator set changes that happened during the previous epoch.
func (s *Service) archiveActiveSetChanges(ctx context.Context, headState *pb.BeaconState) error {
activations := validators.ActivatedValidatorIndices(helpers.PrevEpoch(headState), headState.Validators)
slashings := validators.SlashedValidatorIndices(helpers.PrevEpoch(headState), headState.Validators)
activeValidatorCount, err := helpers.ActiveValidatorCount(headState, helpers.PrevEpoch(headState))
if err != nil {
return errors.Wrap(err, "could not get active validator count")
}
exited, err := validators.ExitedValidatorIndices(headState.Validators, activeValidatorCount)
if err != nil {
return errors.Wrap(err, "could not determine exited validator indices")
}
activeSetChanges := &ethpb.ArchivedActiveSetChanges{
Activated: activations,
Exited: exited,
Slashed: slashings,
}
if err := s.beaconDB.SaveArchivedActiveValidatorChanges(ctx, helpers.PrevEpoch(headState), activeSetChanges); err != nil {
return errors.Wrap(err, "could not archive active validator set changes")
}
return nil
}
// We compute participation metrics by first retrieving the head state and
// matching validator attestations during the epoch.
func (s *Service) archiveParticipation(ctx context.Context, headState *pb.BeaconState) error {
participation, err := epoch.ComputeValidatorParticipation(headState, helpers.SlotToEpoch(headState.Slot))
if err != nil {
return errors.Wrap(err, "could not compute participation")
}
return s.beaconDB.SaveArchivedValidatorParticipation(ctx, helpers.SlotToEpoch(headState.Slot), participation)
}
// We archive validator balances and active indices.
func (s *Service) archiveBalances(ctx context.Context, headState *pb.BeaconState) error {
balances := headState.Balances
currentEpoch := helpers.CurrentEpoch(headState)
if err := s.beaconDB.SaveArchivedBalances(ctx, currentEpoch, balances); err != nil {
return errors.Wrap(err, "could not archive balances")
}
return nil
}
func (s *Service) run(ctx context.Context) {
subChannel := make(chan *statefeed.Event, 1)
sub := s.stateNotifier.StateFeed().Subscribe(subChannel)
defer sub.Unsubscribe()
for {
select {
case event := <-subChannel:
switch event.Type {
case statefeed.BlockProcessed:
data := event.Data.(*statefeed.BlockProcessedData)
log.WithField("headRoot", fmt.Sprintf("%#x", data.BlockRoot)).Debug("Received block processed event")
headState, err := s.headFetcher.HeadState(ctx)
if err != nil {
log.WithError(err).Error("Head state is not available")
continue
}
if !helpers.IsEpochEnd(headState.Slot) {
continue
}
if err := s.archiveCommitteeInfo(ctx, headState); err != nil {
log.WithError(err).Error("Could not archive committee info")
continue
}
if err := s.archiveActiveSetChanges(ctx, headState); err != nil {
log.WithError(err).Error("Could not archive active validator set changes")
continue
}
if err := s.archiveParticipation(ctx, headState); err != nil {
log.WithError(err).Error("Could not archive validator participation")
continue
}
if err := s.archiveBalances(ctx, headState); err != nil {
log.WithError(err).Error("Could not archive validator balances and active indices")
continue
}
log.WithField(
"epoch",
helpers.CurrentEpoch(headState),
).Debug("Successfully archived beacon chain data during epoch")
}
case <-s.ctx.Done():
log.Debug("Context closed, exiting goroutine")
return
case err := <-sub.Err():
log.WithError(err).Error("Subscription to new chain head notifier failed")
return
}
}
}