|
package statesync
|
|
|
|
import (
|
|
"bytes"
|
|
"context"
|
|
"errors"
|
|
"fmt"
|
|
"time"
|
|
|
|
abci "github.com/tendermint/tendermint/abci/types"
|
|
"github.com/tendermint/tendermint/libs/log"
|
|
tmsync "github.com/tendermint/tendermint/libs/sync"
|
|
"github.com/tendermint/tendermint/p2p"
|
|
ssproto "github.com/tendermint/tendermint/proto/tendermint/statesync"
|
|
"github.com/tendermint/tendermint/proxy"
|
|
sm "github.com/tendermint/tendermint/state"
|
|
"github.com/tendermint/tendermint/types"
|
|
)
|
|
|
|
const (
|
|
// chunkFetchers is the number of concurrent chunk fetchers to run.
|
|
chunkFetchers = 4
|
|
// chunkTimeout is the timeout while waiting for the next chunk from the chunk queue.
|
|
chunkTimeout = 2 * time.Minute
|
|
// requestTimeout is the timeout before rerequesting a chunk, possibly from a different peer.
|
|
chunkRequestTimeout = 10 * time.Second
|
|
// minimumDiscoveryTime is the lowest allowable time for a
|
|
// SyncAny discovery time.
|
|
minimumDiscoveryTime = 5 * time.Second
|
|
)
|
|
|
|
var (
|
|
// errAbort is returned by Sync() when snapshot restoration is aborted.
|
|
errAbort = errors.New("state sync aborted")
|
|
// errRetrySnapshot is returned by Sync() when the snapshot should be retried.
|
|
errRetrySnapshot = errors.New("retry snapshot")
|
|
// errRejectSnapshot is returned by Sync() when the snapshot is rejected.
|
|
errRejectSnapshot = errors.New("snapshot was rejected")
|
|
// errRejectFormat is returned by Sync() when the snapshot format is rejected.
|
|
errRejectFormat = errors.New("snapshot format was rejected")
|
|
// errRejectSender is returned by Sync() when the snapshot sender is rejected.
|
|
errRejectSender = errors.New("snapshot sender was rejected")
|
|
// errVerifyFailed is returned by Sync() when app hash or last height verification fails.
|
|
errVerifyFailed = errors.New("verification failed")
|
|
// errTimeout is returned by Sync() when we've waited too long to receive a chunk.
|
|
errTimeout = errors.New("timed out waiting for chunk")
|
|
// errNoSnapshots is returned by SyncAny() if no snapshots are found and discovery is disabled.
|
|
errNoSnapshots = errors.New("no suitable snapshots found")
|
|
)
|
|
|
|
// syncer runs a state sync against an ABCI app. Use either SyncAny() to automatically attempt to
|
|
// sync all snapshots in the pool (pausing to discover new ones), or Sync() to sync a specific
|
|
// snapshot. Snapshots and chunks are fed via AddSnapshot() and AddChunk() as appropriate.
|
|
type syncer struct {
|
|
logger log.Logger
|
|
stateProvider StateProvider
|
|
conn proxy.AppConnSnapshot
|
|
connQuery proxy.AppConnQuery
|
|
snapshots *snapshotPool
|
|
snapshotCh chan<- p2p.Envelope
|
|
chunkCh chan<- p2p.Envelope
|
|
tempDir string
|
|
|
|
mtx tmsync.RWMutex
|
|
chunks *chunkQueue
|
|
}
|
|
|
|
// newSyncer creates a new syncer.
|
|
func newSyncer(
|
|
logger log.Logger,
|
|
conn proxy.AppConnSnapshot,
|
|
connQuery proxy.AppConnQuery,
|
|
stateProvider StateProvider,
|
|
snapshotCh, chunkCh chan<- p2p.Envelope,
|
|
tempDir string,
|
|
) *syncer {
|
|
return &syncer{
|
|
logger: logger,
|
|
stateProvider: stateProvider,
|
|
conn: conn,
|
|
connQuery: connQuery,
|
|
snapshots: newSnapshotPool(stateProvider),
|
|
snapshotCh: snapshotCh,
|
|
chunkCh: chunkCh,
|
|
tempDir: tempDir,
|
|
}
|
|
}
|
|
|
|
// AddChunk adds a chunk to the chunk queue, if any. It returns false if the chunk has already
|
|
// been added to the queue, or an error if there's no sync in progress.
|
|
func (s *syncer) AddChunk(chunk *chunk) (bool, error) {
|
|
s.mtx.RLock()
|
|
defer s.mtx.RUnlock()
|
|
if s.chunks == nil {
|
|
return false, errors.New("no state sync in progress")
|
|
}
|
|
added, err := s.chunks.Add(chunk)
|
|
if err != nil {
|
|
return false, err
|
|
}
|
|
if added {
|
|
s.logger.Debug("Added chunk to queue", "height", chunk.Height, "format", chunk.Format,
|
|
"chunk", chunk.Index)
|
|
} else {
|
|
s.logger.Debug("Ignoring duplicate chunk in queue", "height", chunk.Height, "format", chunk.Format,
|
|
"chunk", chunk.Index)
|
|
}
|
|
return added, nil
|
|
}
|
|
|
|
// AddSnapshot adds a snapshot to the snapshot pool. It returns true if a new, previously unseen
|
|
// snapshot was accepted and added.
|
|
func (s *syncer) AddSnapshot(peerID p2p.NodeID, snapshot *snapshot) (bool, error) {
|
|
added, err := s.snapshots.Add(peerID, snapshot)
|
|
if err != nil {
|
|
return false, err
|
|
}
|
|
if added {
|
|
s.logger.Info("Discovered new snapshot", "height", snapshot.Height, "format", snapshot.Format,
|
|
"hash", snapshot.Hash)
|
|
}
|
|
return added, nil
|
|
}
|
|
|
|
// AddPeer adds a peer to the pool. For now we just keep it simple and send a
|
|
// single request to discover snapshots, later we may want to do retries and stuff.
|
|
func (s *syncer) AddPeer(peerID p2p.NodeID) {
|
|
s.logger.Debug("Requesting snapshots from peer", "peer", peerID)
|
|
s.snapshotCh <- p2p.Envelope{
|
|
To: peerID,
|
|
Message: &ssproto.SnapshotsRequest{},
|
|
}
|
|
}
|
|
|
|
// RemovePeer removes a peer from the pool.
|
|
func (s *syncer) RemovePeer(peerID p2p.NodeID) {
|
|
s.logger.Debug("Removing peer from sync", "peer", peerID)
|
|
s.snapshots.RemovePeer(peerID)
|
|
}
|
|
|
|
// SyncAny tries to sync any of the snapshots in the snapshot pool, waiting to discover further
|
|
// snapshots if none were found and discoveryTime > 0. It returns the latest state and block commit
|
|
// which the caller must use to bootstrap the node.
|
|
func (s *syncer) SyncAny(discoveryTime time.Duration, retryHook func()) (sm.State, *types.Commit, error) {
|
|
if discoveryTime != 0 && discoveryTime < minimumDiscoveryTime {
|
|
discoveryTime = 5 * minimumDiscoveryTime
|
|
}
|
|
|
|
if discoveryTime > 0 {
|
|
s.logger.Info(fmt.Sprintf("Discovering snapshots for %v", discoveryTime))
|
|
time.Sleep(discoveryTime)
|
|
}
|
|
|
|
// The app may ask us to retry a snapshot restoration, in which case we need to reuse
|
|
// the snapshot and chunk queue from the previous loop iteration.
|
|
var (
|
|
snapshot *snapshot
|
|
chunks *chunkQueue
|
|
err error
|
|
)
|
|
for {
|
|
// If not nil, we're going to retry restoration of the same snapshot.
|
|
if snapshot == nil {
|
|
snapshot = s.snapshots.Best()
|
|
chunks = nil
|
|
}
|
|
if snapshot == nil {
|
|
if discoveryTime == 0 {
|
|
return sm.State{}, nil, errNoSnapshots
|
|
}
|
|
retryHook()
|
|
s.logger.Info(fmt.Sprintf("Discovering snapshots for %v", discoveryTime))
|
|
time.Sleep(discoveryTime)
|
|
continue
|
|
}
|
|
if chunks == nil {
|
|
chunks, err = newChunkQueue(snapshot, s.tempDir)
|
|
if err != nil {
|
|
return sm.State{}, nil, fmt.Errorf("failed to create chunk queue: %w", err)
|
|
}
|
|
defer chunks.Close() // in case we forget to close it elsewhere
|
|
}
|
|
|
|
newState, commit, err := s.Sync(snapshot, chunks)
|
|
switch {
|
|
case err == nil:
|
|
return newState, commit, nil
|
|
|
|
case errors.Is(err, errAbort):
|
|
return sm.State{}, nil, err
|
|
|
|
case errors.Is(err, errRetrySnapshot):
|
|
chunks.RetryAll()
|
|
s.logger.Info("Retrying snapshot", "height", snapshot.Height, "format", snapshot.Format,
|
|
"hash", snapshot.Hash)
|
|
continue
|
|
|
|
case errors.Is(err, errTimeout):
|
|
s.snapshots.Reject(snapshot)
|
|
s.logger.Error("Timed out waiting for snapshot chunks, rejected snapshot",
|
|
"height", snapshot.Height, "format", snapshot.Format, "hash", snapshot.Hash)
|
|
|
|
case errors.Is(err, errRejectSnapshot):
|
|
s.snapshots.Reject(snapshot)
|
|
s.logger.Info("Snapshot rejected", "height", snapshot.Height, "format", snapshot.Format,
|
|
"hash", snapshot.Hash)
|
|
|
|
case errors.Is(err, errRejectFormat):
|
|
s.snapshots.RejectFormat(snapshot.Format)
|
|
s.logger.Info("Snapshot format rejected", "format", snapshot.Format)
|
|
|
|
case errors.Is(err, errRejectSender):
|
|
s.logger.Info("Snapshot senders rejected", "height", snapshot.Height, "format", snapshot.Format,
|
|
"hash", snapshot.Hash)
|
|
for _, peer := range s.snapshots.GetPeers(snapshot) {
|
|
s.snapshots.RejectPeer(peer)
|
|
s.logger.Info("Snapshot sender rejected", "peer", peer)
|
|
}
|
|
|
|
default:
|
|
return sm.State{}, nil, fmt.Errorf("snapshot restoration failed: %w", err)
|
|
}
|
|
|
|
// Discard snapshot and chunks for next iteration
|
|
err = chunks.Close()
|
|
if err != nil {
|
|
s.logger.Error("Failed to clean up chunk queue", "err", err)
|
|
}
|
|
snapshot = nil
|
|
chunks = nil
|
|
}
|
|
}
|
|
|
|
// Sync executes a sync for a specific snapshot, returning the latest state and block commit which
|
|
// the caller must use to bootstrap the node.
|
|
func (s *syncer) Sync(snapshot *snapshot, chunks *chunkQueue) (sm.State, *types.Commit, error) {
|
|
s.mtx.Lock()
|
|
if s.chunks != nil {
|
|
s.mtx.Unlock()
|
|
return sm.State{}, nil, errors.New("a state sync is already in progress")
|
|
}
|
|
s.chunks = chunks
|
|
s.mtx.Unlock()
|
|
defer func() {
|
|
s.mtx.Lock()
|
|
s.chunks = nil
|
|
s.mtx.Unlock()
|
|
}()
|
|
|
|
// Offer snapshot to ABCI app.
|
|
err := s.offerSnapshot(snapshot)
|
|
if err != nil {
|
|
return sm.State{}, nil, err
|
|
}
|
|
|
|
// Spawn chunk fetchers. They will terminate when the chunk queue is closed or context canceled.
|
|
ctx, cancel := context.WithCancel(context.Background())
|
|
defer cancel()
|
|
for i := int32(0); i < chunkFetchers; i++ {
|
|
go s.fetchChunks(ctx, snapshot, chunks)
|
|
}
|
|
|
|
pctx, pcancel := context.WithTimeout(context.Background(), 10*time.Second)
|
|
defer pcancel()
|
|
|
|
// Optimistically build new state, so we don't discover any light client failures at the end.
|
|
state, err := s.stateProvider.State(pctx, snapshot.Height)
|
|
if err != nil {
|
|
return sm.State{}, nil, fmt.Errorf("failed to build new state: %w", err)
|
|
}
|
|
commit, err := s.stateProvider.Commit(pctx, snapshot.Height)
|
|
if err != nil {
|
|
return sm.State{}, nil, fmt.Errorf("failed to fetch commit: %w", err)
|
|
}
|
|
|
|
// Restore snapshot
|
|
err = s.applyChunks(chunks)
|
|
if err != nil {
|
|
return sm.State{}, nil, err
|
|
}
|
|
|
|
// Verify app and update app version
|
|
appVersion, err := s.verifyApp(snapshot)
|
|
if err != nil {
|
|
return sm.State{}, nil, err
|
|
}
|
|
state.Version.Consensus.App = appVersion
|
|
|
|
// Done! 🎉
|
|
s.logger.Info("Snapshot restored", "height", snapshot.Height, "format", snapshot.Format,
|
|
"hash", snapshot.Hash)
|
|
|
|
return state, commit, nil
|
|
}
|
|
|
|
// offerSnapshot offers a snapshot to the app. It returns various errors depending on the app's
|
|
// response, or nil if the snapshot was accepted.
|
|
func (s *syncer) offerSnapshot(snapshot *snapshot) error {
|
|
s.logger.Info("Offering snapshot to ABCI app", "height", snapshot.Height,
|
|
"format", snapshot.Format, "hash", snapshot.Hash)
|
|
resp, err := s.conn.OfferSnapshotSync(context.Background(), abci.RequestOfferSnapshot{
|
|
Snapshot: &abci.Snapshot{
|
|
Height: snapshot.Height,
|
|
Format: snapshot.Format,
|
|
Chunks: snapshot.Chunks,
|
|
Hash: snapshot.Hash,
|
|
Metadata: snapshot.Metadata,
|
|
},
|
|
AppHash: snapshot.trustedAppHash,
|
|
})
|
|
if err != nil {
|
|
return fmt.Errorf("failed to offer snapshot: %w", err)
|
|
}
|
|
switch resp.Result {
|
|
case abci.ResponseOfferSnapshot_ACCEPT:
|
|
s.logger.Info("Snapshot accepted, restoring", "height", snapshot.Height,
|
|
"format", snapshot.Format, "hash", snapshot.Hash)
|
|
return nil
|
|
case abci.ResponseOfferSnapshot_ABORT:
|
|
return errAbort
|
|
case abci.ResponseOfferSnapshot_REJECT:
|
|
return errRejectSnapshot
|
|
case abci.ResponseOfferSnapshot_REJECT_FORMAT:
|
|
return errRejectFormat
|
|
case abci.ResponseOfferSnapshot_REJECT_SENDER:
|
|
return errRejectSender
|
|
default:
|
|
return fmt.Errorf("unknown ResponseOfferSnapshot result %v", resp.Result)
|
|
}
|
|
}
|
|
|
|
// applyChunks applies chunks to the app. It returns various errors depending on the app's
|
|
// response, or nil once the snapshot is fully restored.
|
|
func (s *syncer) applyChunks(chunks *chunkQueue) error {
|
|
for {
|
|
chunk, err := chunks.Next()
|
|
if err == errDone {
|
|
return nil
|
|
} else if err != nil {
|
|
return fmt.Errorf("failed to fetch chunk: %w", err)
|
|
}
|
|
|
|
resp, err := s.conn.ApplySnapshotChunkSync(context.Background(), abci.RequestApplySnapshotChunk{
|
|
Index: chunk.Index,
|
|
Chunk: chunk.Chunk,
|
|
Sender: string(chunk.Sender),
|
|
})
|
|
if err != nil {
|
|
return fmt.Errorf("failed to apply chunk %v: %w", chunk.Index, err)
|
|
}
|
|
s.logger.Info("Applied snapshot chunk to ABCI app", "height", chunk.Height,
|
|
"format", chunk.Format, "chunk", chunk.Index, "total", chunks.Size())
|
|
|
|
// Discard and refetch any chunks as requested by the app
|
|
for _, index := range resp.RefetchChunks {
|
|
err := chunks.Discard(index)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to discard chunk %v: %w", index, err)
|
|
}
|
|
}
|
|
|
|
// Reject any senders as requested by the app
|
|
for _, sender := range resp.RejectSenders {
|
|
if sender != "" {
|
|
peerID := p2p.NodeID(sender)
|
|
s.snapshots.RejectPeer(peerID)
|
|
|
|
if err := chunks.DiscardSender(peerID); err != nil {
|
|
return fmt.Errorf("failed to reject sender: %w", err)
|
|
}
|
|
}
|
|
}
|
|
|
|
switch resp.Result {
|
|
case abci.ResponseApplySnapshotChunk_ACCEPT:
|
|
case abci.ResponseApplySnapshotChunk_ABORT:
|
|
return errAbort
|
|
case abci.ResponseApplySnapshotChunk_RETRY:
|
|
chunks.Retry(chunk.Index)
|
|
case abci.ResponseApplySnapshotChunk_RETRY_SNAPSHOT:
|
|
return errRetrySnapshot
|
|
case abci.ResponseApplySnapshotChunk_REJECT_SNAPSHOT:
|
|
return errRejectSnapshot
|
|
default:
|
|
return fmt.Errorf("unknown ResponseApplySnapshotChunk result %v", resp.Result)
|
|
}
|
|
}
|
|
}
|
|
|
|
// fetchChunks requests chunks from peers, receiving allocations from the chunk queue. Chunks
|
|
// will be received from the reactor via syncer.AddChunks() to chunkQueue.Add().
|
|
func (s *syncer) fetchChunks(ctx context.Context, snapshot *snapshot, chunks *chunkQueue) {
|
|
for {
|
|
index, err := chunks.Allocate()
|
|
if err == errDone {
|
|
// Keep checking until the context is canceled (restore is done), in case any
|
|
// chunks need to be refetched.
|
|
select {
|
|
case <-ctx.Done():
|
|
return
|
|
default:
|
|
}
|
|
time.Sleep(2 * time.Second)
|
|
continue
|
|
}
|
|
if err != nil {
|
|
s.logger.Error("Failed to allocate chunk from queue", "err", err)
|
|
return
|
|
}
|
|
s.logger.Info("Fetching snapshot chunk", "height", snapshot.Height,
|
|
"format", snapshot.Format, "chunk", index, "total", chunks.Size())
|
|
|
|
ticker := time.NewTicker(chunkRequestTimeout)
|
|
defer ticker.Stop()
|
|
s.requestChunk(snapshot, index)
|
|
select {
|
|
case <-chunks.WaitFor(index):
|
|
case <-ticker.C:
|
|
s.requestChunk(snapshot, index)
|
|
case <-ctx.Done():
|
|
return
|
|
}
|
|
ticker.Stop()
|
|
}
|
|
}
|
|
|
|
// requestChunk requests a chunk from a peer.
|
|
func (s *syncer) requestChunk(snapshot *snapshot, chunk uint32) {
|
|
peer := s.snapshots.GetPeer(snapshot)
|
|
if peer == "" {
|
|
s.logger.Error("No valid peers found for snapshot", "height", snapshot.Height,
|
|
"format", snapshot.Format, "hash", snapshot.Hash)
|
|
return
|
|
}
|
|
|
|
s.logger.Debug(
|
|
"Requesting snapshot chunk",
|
|
"height", snapshot.Height,
|
|
"format", snapshot.Format,
|
|
"chunk", chunk,
|
|
"peer", peer,
|
|
)
|
|
|
|
s.chunkCh <- p2p.Envelope{
|
|
To: peer,
|
|
Message: &ssproto.ChunkRequest{
|
|
Height: snapshot.Height,
|
|
Format: snapshot.Format,
|
|
Index: chunk,
|
|
},
|
|
}
|
|
}
|
|
|
|
// verifyApp verifies the sync, checking the app hash and last block height. It returns the
|
|
// app version, which should be returned as part of the initial state.
|
|
func (s *syncer) verifyApp(snapshot *snapshot) (uint64, error) {
|
|
resp, err := s.connQuery.InfoSync(context.Background(), proxy.RequestInfo)
|
|
if err != nil {
|
|
return 0, fmt.Errorf("failed to query ABCI app for appHash: %w", err)
|
|
}
|
|
|
|
if !bytes.Equal(snapshot.trustedAppHash, resp.LastBlockAppHash) {
|
|
s.logger.Error("appHash verification failed",
|
|
"expected", snapshot.trustedAppHash,
|
|
"actual", resp.LastBlockAppHash)
|
|
return 0, errVerifyFailed
|
|
}
|
|
|
|
if uint64(resp.LastBlockHeight) != snapshot.Height {
|
|
s.logger.Error(
|
|
"ABCI app reported unexpected last block height",
|
|
"expected", snapshot.Height,
|
|
"actual", resp.LastBlockHeight,
|
|
)
|
|
return 0, errVerifyFailed
|
|
}
|
|
|
|
s.logger.Info("Verified ABCI app", "height", snapshot.Height, "appHash", snapshot.trustedAppHash)
|
|
return resp.AppVersion, nil
|
|
}
|