cmd, eth, internal: introduce debug_sync (#32177)

Alternative implementation of #32159

Author: rjl493456442

cmd/geth/config.go

@@ -262,14 +262,16 @@ func makeFullNode(ctx *cli.Context) *node.Node {
 	if cfg.Ethstats.URL != "" {
 		utils.RegisterEthStatsService(stack, backend, cfg.Ethstats.URL)
 	}
-	// Configure full-sync tester service if requested
+	// Configure synchronization override service
+	var synctarget common.Hash
 	if ctx.IsSet(utils.SyncTargetFlag.Name) {
 		hex := hexutil.MustDecode(ctx.String(utils.SyncTargetFlag.Name))
 		if len(hex) != common.HashLength {
 			utils.Fatalf("invalid sync target length: have %d, want %d", len(hex), common.HashLength)
 		}
-		utils.RegisterFullSyncTester(stack, eth, common.BytesToHash(hex), ctx.Bool(utils.ExitWhenSyncedFlag.Name))
+		synctarget = common.BytesToHash(hex)
 	}
+	utils.RegisterSyncOverrideService(stack, eth, synctarget, ctx.Bool(utils.ExitWhenSyncedFlag.Name))
 
 	if ctx.IsSet(utils.DeveloperFlag.Name) {
 		// Start dev mode.

cmd/utils/flags.go

@@ -49,10 +49,10 @@ import (
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/crypto/kzg4844"
 	"github.com/ethereum/go-ethereum/eth"
-	"github.com/ethereum/go-ethereum/eth/catalyst"
 	"github.com/ethereum/go-ethereum/eth/ethconfig"
 	"github.com/ethereum/go-ethereum/eth/filters"
 	"github.com/ethereum/go-ethereum/eth/gasprice"
+	"github.com/ethereum/go-ethereum/eth/syncer"
 	"github.com/ethereum/go-ethereum/eth/tracers"
 	"github.com/ethereum/go-ethereum/ethdb"
 	"github.com/ethereum/go-ethereum/ethdb/remotedb"
@@ -1997,10 +1997,14 @@ func RegisterFilterAPI(stack *node.Node, backend ethapi.Backend, ethcfg *ethconf
 	return filterSystem
 }
 
-// RegisterFullSyncTester adds the full-sync tester service into node.
-func RegisterFullSyncTester(stack *node.Node, eth *eth.Ethereum, target common.Hash, exitWhenSynced bool) {
-	catalyst.RegisterFullSyncTester(stack, eth, target, exitWhenSynced)
-	log.Info("Registered full-sync tester", "hash", target, "exitWhenSynced", exitWhenSynced)
+// RegisterSyncOverrideService adds the synchronization override service into node.
+func RegisterSyncOverrideService(stack *node.Node, eth *eth.Ethereum, target common.Hash, exitWhenSynced bool) {
+	if target != (common.Hash{}) {
+		log.Info("Registered sync override service", "hash", target, "exitWhenSynced", exitWhenSynced)
+	} else {
+		log.Info("Registered sync override service")
+	}
+	syncer.Register(stack, eth, target, exitWhenSynced)
 }
 
 // SetupMetrics configures the metrics system.

eth/catalyst/tester.go

@@ -18,7 +18,6 @@ package downloader
 
 import (
 	"errors"
-	"time"
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
@@ -34,28 +33,14 @@ import (
 // Note, this must not be used in live code. If the forkchcoice endpoint where
 // to use this instead of giving us the payload first, then essentially nobody
 // in the network would have the block yet that we'd attempt to retrieve.
-func (d *Downloader) BeaconDevSync(mode SyncMode, hash common.Hash, stop chan struct{}) error {
+func (d *Downloader) BeaconDevSync(mode SyncMode, header *types.Header) error {
 	// Be very loud that this code should not be used in a live node
 	log.Warn("----------------------------------")
-	log.Warn("Beacon syncing with hash as target", "hash", hash)
+	log.Warn("Beacon syncing with hash as target", "number", header.Number, "hash", header.Hash())
 	log.Warn("This is unhealthy for a live node!")
+	log.Warn("This is incompatible with the consensus layer!")
 	log.Warn("----------------------------------")
-
-	log.Info("Waiting for peers to retrieve sync target")
-	for {
-		// If the node is going down, unblock
-		select {
-		case <-stop:
-			return errors.New("stop requested")
-		default:
-		}
-		header, err := d.GetHeader(hash)
-		if err != nil {
-			time.Sleep(time.Second)
-			continue
-		}
-		return d.BeaconSync(mode, header, header)
-	}
+	return d.BeaconSync(mode, header, header)
 }
 
 // GetHeader tries to retrieve the header with a given hash from a random peer.

eth/downloader/beacondevsync.go

@@ -45,9 +45,6 @@ func (d *Downloader) fetchHeadersByHash(p *peerConnection, hash common.Hash, amo
 	defer timeoutTimer.Stop()
 
 	select {
-	case <-d.cancelCh:
-		return nil, nil, errCanceled
-
 	case <-timeoutTimer.C:
 		// Header retrieval timed out, update the metrics
 		p.log.Debug("Header request timed out", "elapsed", ttl)