mirror of https://github.com/certusone/vouch.git
74 lines
2.4 KiB
Go
74 lines
2.4 KiB
Go
// Copyright © 2020 Attestant Limited.
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
package best
|
|
|
|
import (
|
|
"context"
|
|
"sync"
|
|
"time"
|
|
|
|
eth2client "github.com/attestantio/go-eth2-client"
|
|
spec "github.com/attestantio/go-eth2-client/spec/phase0"
|
|
"golang.org/x/sync/semaphore"
|
|
)
|
|
|
|
// AttestationData provides the best attestation data from a number of beacon nodes.
|
|
func (s *Service) AttestationData(ctx context.Context, slot uint64, committeeIndex uint64) (*spec.AttestationData, error) {
|
|
var mu sync.Mutex
|
|
bestScore := float64(0)
|
|
var bestAttestationData *spec.AttestationData
|
|
|
|
sem := semaphore.NewWeighted(s.processConcurrency)
|
|
var wg sync.WaitGroup
|
|
for name, provider := range s.attestationDataProviders {
|
|
wg.Add(1)
|
|
go func(ctx context.Context, sem *semaphore.Weighted, wg *sync.WaitGroup, name string, provider eth2client.AttestationDataProvider, mu *sync.Mutex) {
|
|
defer wg.Done()
|
|
|
|
if err := sem.Acquire(ctx, 1); err != nil {
|
|
log.Error().Err(err).Msg("Failed to acquire semaphore")
|
|
return
|
|
}
|
|
defer sem.Release(1)
|
|
log := log.With().Str("provider", name).Uint64("slot", slot).Logger()
|
|
|
|
opCtx, cancel := context.WithTimeout(ctx, s.timeout)
|
|
started := time.Now()
|
|
attestationData, err := provider.AttestationData(opCtx, slot, committeeIndex)
|
|
s.clientMonitor.ClientOperation(name, "attestation data", err == nil, time.Since(started))
|
|
if err != nil {
|
|
log.Warn().Err(err).Msg("Failed to obtain attestation data")
|
|
cancel()
|
|
return
|
|
}
|
|
log.Trace().Dur("elapsed", time.Since(started)).Msg("Obtained attestation data")
|
|
cancel()
|
|
if attestationData == nil {
|
|
return
|
|
}
|
|
|
|
mu.Lock()
|
|
score := s.scoreAttestationData(ctx, name, attestationData)
|
|
if score > bestScore || bestAttestationData == nil {
|
|
bestScore = score
|
|
bestAttestationData = attestationData
|
|
}
|
|
mu.Unlock()
|
|
}(ctx, sem, &wg, name, provider, &mu)
|
|
}
|
|
wg.Wait()
|
|
|
|
return bestAttestationData, nil
|
|
}
|