Fix raft applied index out of range

raft/backend.go

@@ -5,10 +5,9 @@ import (
 	"sync"
 	"time"
 
-	"github.com/ethereum/go-ethereum/core/types"
-
 	"github.com/ethereum/go-ethereum/accounts"
 	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/eth"
 	"github.com/ethereum/go-ethereum/eth/downloader"
 	"github.com/ethereum/go-ethereum/ethdb"

raft/handler.go

@@ -10,29 +10,27 @@ import (
 	"sync"
 	"time"
 
-	"golang.org/x/net/context"
-
+	"github.com/coreos/etcd/etcdserver/stats"
 	"github.com/coreos/etcd/pkg/fileutil"
+	raftTypes "github.com/coreos/etcd/pkg/types"
+	etcdRaft "github.com/coreos/etcd/raft"
+	"github.com/coreos/etcd/raft/raftpb"
+	"github.com/coreos/etcd/rafthttp"
 	"github.com/coreos/etcd/snap"
 	"github.com/coreos/etcd/wal"
+	mapset "github.com/deckarep/golang-set"
+	"github.com/syndtr/goleveldb/leveldb"
+	"golang.org/x/net/context"
+
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/eth/downloader"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/p2p"
-	"github.com/ethereum/go-ethereum/rlp"
-
-	"github.com/coreos/etcd/etcdserver/stats"
-	raftTypes "github.com/coreos/etcd/pkg/types"
-	etcdRaft "github.com/coreos/etcd/raft"
-	"github.com/coreos/etcd/raft/raftpb"
-	"github.com/coreos/etcd/rafthttp"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/enr"
-	"github.com/syndtr/goleveldb/leveldb"
-
-	mapset "github.com/deckarep/golang-set"
+	"github.com/ethereum/go-ethereum/rlp"
 )
 
 type ProtocolManager struct {
@@ -426,6 +424,19 @@ func (pm *ProtocolManager) startRaft() {
 				// the single call to `pm.applyNewChainHead` for more context.
 				lastAppliedIndex = lastPersistedCommittedIndex
 			}
+
+			// fix raft applied index out of range
+			firstIndex, err := pm.raftStorage.FirstIndex()
+			if err != nil {
+				panic(fmt.Sprintf("failed to read last persisted applied index from raft while restarting: %v", err))
+			}
+			lastPersistedAppliedIndex := firstIndex - 1
+			if lastPersistedAppliedIndex > lastAppliedIndex {
+				log.Debug("set lastAppliedIndex to lastPersistedAppliedIndex", "last applied index", lastAppliedIndex, "last persisted applied index", lastPersistedAppliedIndex)
+
+				lastAppliedIndex = lastPersistedAppliedIndex
+				pm.advanceAppliedIndex(lastAppliedIndex)
+			}
 		}
 	}
 

raft/handler_test.go

@@ -0,0 +1,155 @@
+package raft
+
+import (
+	"crypto/ecdsa"
+	"fmt"
+	"io/ioutil"
+	"net"
+	"os"
+	"reflect"
+	"testing"
+	"time"
+	"unsafe"
+
+	"github.com/ethereum/go-ethereum/core"
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/ethereum/go-ethereum/eth"
+	"github.com/ethereum/go-ethereum/event"
+	"github.com/ethereum/go-ethereum/log"
+	"github.com/ethereum/go-ethereum/node"
+	"github.com/ethereum/go-ethereum/p2p"
+	"github.com/ethereum/go-ethereum/p2p/enode"
+	"github.com/ethereum/go-ethereum/params"
+)
+
+// pm.advanceAppliedIndex() and state updates are in different
+// transaction boundaries hence there's a probablity that they are
+// out of sync due to premature shutdown
+func TestProtocolManager_whenAppliedIndexOutOfSync(t *testing.T) {
+	tmpWorkingDir, err := ioutil.TempDir("", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer func() {
+		_ = os.RemoveAll(tmpWorkingDir)
+	}()
+	count := 3
+	ports := make([]uint16, count)
+	nodeKeys := make([]*ecdsa.PrivateKey, count)
+	peers := make([]*enode.Node, count)
+	for i := 0; i < count; i++ {
+		ports[i] = nextPort(t)
+		nodeKeys[i] = mustNewNodeKey(t)
+		peers[i] = enode.NewV4(&(nodeKeys[i].PublicKey), net.IPv4(127, 0, 0, 1), 0, 0, int(ports[i]))
+	}
+	raftNodes := make([]*RaftService, count)
+	for i := 0; i < count; i++ {
+		if s, err := startRaftNode(uint16(i+1), ports[i], tmpWorkingDir, nodeKeys[i], peers); err != nil {
+			t.Fatal(err)
+		} else {
+			raftNodes[i] = s
+		}
+	}
+	waitFunc := func() {
+		for {
+			time.Sleep(200 * time.Millisecond)
+			for i := 0; i < count; i++ {
+				if raftNodes[i].raftProtocolManager.role == minterRole {
+					return
+				}
+			}
+		}
+	}
+	waitFunc()
+	// update the index to mimic the issue (set applied index behind for node 0)
+	raftNodes[0].raftProtocolManager.advanceAppliedIndex(1)
+	// now stop and restart the nodes
+	for i := 0; i < count; i++ {
+		if err := raftNodes[i].Stop(); err != nil {
+			t.Fatal(err)
+		}
+	}
+	log.Debug("restart raft cluster")
+	for i := 0; i < count; i++ {
+		if s, err := startRaftNode(uint16(i+1), ports[i], tmpWorkingDir, nodeKeys[i], peers); err != nil {
+			t.Fatal(err)
+		} else {
+			raftNodes[i] = s
+		}
+	}
+	waitFunc()
+}
+
+func mustNewNodeKey(t *testing.T) *ecdsa.PrivateKey {
+	k, err := crypto.GenerateKey()
+	if err != nil {
+		t.Fatal(err)
+	}
+	return k
+}
+
+func nextPort(t *testing.T) uint16 {
+	listener, err := net.Listen("tcp", ":0")
+	if err != nil {
+		t.Fatal(err)
+	}
+	return uint16(listener.Addr().(*net.TCPAddr).Port)
+}
+
+func prepareServiceContext(key *ecdsa.PrivateKey) (ctx *node.ServiceContext, cfg *node.Config, err error) {
+	defer func() {
+		if r := recover(); r != nil {
+			err = fmt.Errorf("%s", r)
+			ctx = nil
+			cfg = nil
+		}
+	}()
+	cfg = &node.Config{
+		P2P: p2p.Config{
+			PrivateKey: key,
+		},
+	}
+	ctx = &node.ServiceContext{
+		EventMux: new(event.TypeMux),
+	}
+	// config is private field so we need some workaround to set the value
+	configField := reflect.ValueOf(ctx).Elem().FieldByName("config")
+	configField = reflect.NewAt(configField.Type(), unsafe.Pointer(configField.UnsafeAddr())).Elem()
+	configField.Set(reflect.ValueOf(cfg))
+	return
+}
+
+func startRaftNode(id, port uint16, tmpWorkingDir string, key *ecdsa.PrivateKey, nodes []*enode.Node) (*RaftService, error) {
+	datadir := fmt.Sprintf("%s/node%d", tmpWorkingDir, id)
+
+	ctx, _, err := prepareServiceContext(key)
+	if err != nil {
+		return nil, err
+	}
+
+	e, err := eth.New(ctx, &eth.Config{
+		Genesis: &core.Genesis{Config: params.QuorumTestChainConfig},
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	s, err := New(ctx, params.QuorumTestChainConfig, id, port, false, 100*time.Millisecond, e, nodes, datadir)
+	if err != nil {
+		return nil, err
+	}
+
+	srv := &p2p.Server{
+		Config: p2p.Config{
+			PrivateKey: key,
+		},
+	}
+	if err := srv.Start(); err != nil {
+		return nil, fmt.Errorf("could not start: %v", err)
+	}
+	if err := s.Start(srv); err != nil {
+		return nil, err
+	}
+
+	return s, nil
+}

raft/snapshot.go

@@ -10,7 +10,8 @@ import (
 	"github.com/coreos/etcd/raft/raftpb"
 	"github.com/coreos/etcd/snap"
 	"github.com/coreos/etcd/wal/walpb"
-	"github.com/deckarep/golang-set"
+	mapset "github.com/deckarep/golang-set"
+
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/eth/downloader"

raft/speculative_chain.go

@@ -1,12 +1,12 @@
 package raft
 
 import (
+	mapset "github.com/deckarep/golang-set"
+	"gopkg.in/oleiade/lane.v1"
+
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
-
-	"github.com/deckarep/golang-set"
-	"gopkg.in/oleiade/lane.v1"
 )
 
 // The speculative chain represents blocks that we have minted which haven't been accepted into the chain yet, building