etcdserver: Unify memory storage boostrap

server/etcdserver/raft.go

@@ -33,7 +33,6 @@ import (
 	"go.etcd.io/etcd/server/v3/etcdserver/api/membership"
 	"go.etcd.io/etcd/server/v3/etcdserver/api/rafthttp"
 	"go.etcd.io/etcd/server/v3/etcdserver/api/snap"
-	"go.etcd.io/etcd/server/v3/wal/walpb"
 	"go.uber.org/zap"
 )
 
@@ -437,8 +436,7 @@ func boostrapRaftFromCluster(cfg config.ServerConfig, cl *membership.RaftCluster
 		zap.String("local-member-id", id.String()),
 		zap.String("cluster-id", cl.ID().String()),
 	)
-	s := raft.NewMemoryStorage()
+	s := wal.MemoryStorage()
-
 	return &boostrapRaft{
 		lg:        cfg.Logger,
 		heartbeat: time.Duration(cfg.TickMs) * time.Millisecond,
@@ -451,11 +449,7 @@ func boostrapRaftFromCluster(cfg config.ServerConfig, cl *membership.RaftCluster
 }
 
 func boostrapRaftFromWal(cfg config.ServerConfig, snapshot *raftpb.Snapshot) *boostrapRaft {
-	var walsnap walpb.Snapshot
+	wal := boostrapWALFromSnapshot(cfg.Logger, cfg.WALDir(), snapshot, cfg.UnsafeNoFsync)
-	if snapshot != nil {
-		walsnap.Index, walsnap.Term = snapshot.Metadata.Index, snapshot.Metadata.Term
-	}
-	wal := boostrapWALFromSnapshot(cfg.Logger, cfg.WALDir(), walsnap, cfg.UnsafeNoFsync)
 
 	cfg.Logger.Info(
 		"restarting local member",
@@ -465,12 +459,7 @@ func boostrapRaftFromWal(cfg config.ServerConfig, snapshot *raftpb.Snapshot) *bo
 	)
 	cl := membership.NewCluster(cfg.Logger)
 	cl.SetID(wal.id, wal.cid)
-	s := raft.NewMemoryStorage()
+	s := wal.MemoryStorage()
-	if snapshot != nil {
-		s.ApplySnapshot(*snapshot)
-	}
-	s.SetHardState(*wal.st)
-	s.Append(wal.ents)
 	return &boostrapRaft{
 		lg:        cfg.Logger,
 		heartbeat: time.Duration(cfg.TickMs) * time.Millisecond,
@@ -482,11 +471,7 @@ func boostrapRaftFromWal(cfg config.ServerConfig, snapshot *raftpb.Snapshot) *bo
 }
 
 func boostrapRaftFromWalStandalone(cfg config.ServerConfig, snapshot *raftpb.Snapshot) *boostrapRaft {
-	var walsnap walpb.Snapshot
+	wal := boostrapWALFromSnapshot(cfg.Logger, cfg.WALDir(), snapshot, cfg.UnsafeNoFsync)
-	if snapshot != nil {
-		walsnap.Index, walsnap.Term = snapshot.Metadata.Index, snapshot.Metadata.Term
-	}
-	wal := boostrapWALFromSnapshot(cfg.Logger, cfg.WALDir(), walsnap, cfg.UnsafeNoFsync)
 
 	// discard the previously uncommitted entries
 	for i, ent := range wal.ents {
@@ -530,12 +515,7 @@ func boostrapRaftFromWalStandalone(cfg config.ServerConfig, snapshot *raftpb.Sna
 
 	cl := membership.NewCluster(cfg.Logger)
 	cl.SetID(wal.id, wal.cid)
-	s := raft.NewMemoryStorage()
+	s := wal.MemoryStorage()
-	if snapshot != nil {
-		s.ApplySnapshot(*snapshot)
-	}
-	s.SetHardState(*wal.st)
-	s.Append(wal.ents)
 	return &boostrapRaft{
 		lg:        cfg.Logger,
 		heartbeat: time.Duration(cfg.TickMs) * time.Millisecond,

server/etcdserver/storage.go

@@ -20,6 +20,7 @@ import (
 	pb "go.etcd.io/etcd/api/v3/etcdserverpb"
 	"go.etcd.io/etcd/client/pkg/v3/types"
 	"go.etcd.io/etcd/pkg/v3/pbutil"
+	"go.etcd.io/etcd/raft/v3"
 	"go.etcd.io/etcd/raft/v3/raftpb"
 	"go.etcd.io/etcd/server/v3/config"
 	"go.etcd.io/etcd/server/v3/etcdserver/api/snap"
@@ -84,10 +85,14 @@ func (st *storage) Release(snap raftpb.Snapshot) error {
 // boostrapWALFromSnapshot reads the WAL at the given snap and returns the wal, its latest HardState and cluster ID, and all entries that appear
 // after the position of the given snap in the WAL.
 // The snap must have been previously saved to the WAL, or this call will panic.
-func boostrapWALFromSnapshot(lg *zap.Logger, waldir string, snap walpb.Snapshot, unsafeNoFsync bool) *boostrappedWAL {
+func boostrapWALFromSnapshot(lg *zap.Logger, waldir string, snapshot *raftpb.Snapshot, unsafeNoFsync bool) *boostrappedWAL {
+	var walsnap walpb.Snapshot
+	if snapshot != nil {
+		walsnap.Index, walsnap.Term = snapshot.Metadata.Index, snapshot.Metadata.Term
+	}
 	repaired := false
 	for {
-		w, err := wal.Open(lg, waldir, snap)
+		w, err := wal.Open(lg, waldir, walsnap)
 		if err != nil {
 			lg.Fatal("failed to open WAL", zap.Error(err))
 		}
@@ -119,6 +124,7 @@ func boostrapWALFromSnapshot(lg *zap.Logger, waldir string, snap walpb.Snapshot,
 			cid:      cid,
 			st:       &st,
 			ents:     ents,
+			snapshot: snapshot,
 		}
 	}
 }
@@ -149,4 +155,19 @@ type boostrappedWAL struct {
 	id, cid  types.ID
 	st       *raftpb.HardState
 	ents     []raftpb.Entry
+	snapshot *raftpb.Snapshot
+}
+
+func (wal *boostrappedWAL) MemoryStorage() *raft.MemoryStorage {
+	s := raft.NewMemoryStorage()
+	if wal.snapshot != nil {
+		s.ApplySnapshot(*wal.snapshot)
+	}
+	if wal.st != nil {
+		s.SetHardState(*wal.st)
+	}
+	if len(wal.ents) != 0 {
+		s.Append(wal.ents)
+	}
+	return s
 }