// startRaft starts a raft node from the given wal dir.
// If the wal dir does not exist, startRaft will start a new raft node.
// If the wal dir exists, startRaft will restart the previous raft node.
// startRaft returns the started raft node and the opened wal.
func startRaft(id int64, peerIDs []int64, waldir string) (raft.Node, *wal.WAL) {
if !wal.Exist(waldir) {
w, err := wal.Create(waldir)
if err != nil {
log.Fatal(err)
}
n := raft.Start(id, peerIDs, 10, 1)
return n, w
}
// restart a node from previous wal
// TODO(xiangli): check snapshot; not open from one
w, err := wal.OpenAtIndex(waldir, 1)
if err != nil {
log.Fatal(err)
}
wid, st, ents, err := w.ReadAll()
// TODO(xiangli): save/recovery nodeID?
if wid != 0 {
log.Fatalf("unexpected nodeid %d: nodeid should always be zero until we save nodeid into wal", wid)
}
if err != nil {
log.Fatal(err)
}
n := raft.Restart(id, peerIDs, 10, 1, st, ents)
return n, w
}
func startNode(cfg *ServerConfig, ids []types.ID) (id types.ID, n raft.Node, s *raft.MemoryStorage, w *wal.WAL) {
var err error
member := cfg.Cluster.MemberByName(cfg.Name)
metadata := pbutil.MustMarshal(
&pb.Metadata{
NodeID: uint64(member.ID),
ClusterID: uint64(cfg.Cluster.ID()),
},
)
if err := os.MkdirAll(cfg.SnapDir(), privateDirMode); err != nil {
log.Fatalf("etcdserver create snapshot directory error: %v", err)
}
if w, err = wal.Create(cfg.WALDir(), metadata); err != nil {
log.Fatalf("etcdserver: create wal error: %v", err)
}
peers := make([]raft.Peer, len(ids))
for i, id := range ids {
ctx, err := json.Marshal((*cfg.Cluster).Member(id))
if err != nil {
log.Panicf("marshal member should never fail: %v", err)
}
peers[i] = raft.Peer{ID: uint64(id), Context: ctx}
}
id = member.ID
log.Printf("etcdserver: start member %s in cluster %s", id, cfg.Cluster.ID())
s = raft.NewMemoryStorage()
n = raft.StartNode(uint64(id), peers, 10, 1, s)
return
}
// handleBackup handles a request that intends to do a backup.
func handleBackup(c *cli.Context) {
srcSnap := path.Join(c.String("data-dir"), "member", "snap")
destSnap := path.Join(c.String("backup-dir"), "member", "snap")
srcWAL := path.Join(c.String("data-dir"), "member", "wal")
destWAL := path.Join(c.String("backup-dir"), "member", "wal")
if err := os.MkdirAll(destSnap, 0700); err != nil {
log.Fatalf("failed creating backup snapshot dir %v: %v", destSnap, err)
}
ss := snap.New(srcSnap)
snapshot, err := ss.Load()
if err != nil && err != snap.ErrNoSnapshot {
log.Fatal(err)
}
var walsnap walpb.Snapshot
if snapshot != nil {
walsnap.Index, walsnap.Term = snapshot.Metadata.Index, snapshot.Metadata.Term
newss := snap.New(destSnap)
if err = newss.SaveSnap(*snapshot); err != nil {
log.Fatal(err)
}
}
w, err := wal.OpenForRead(srcWAL, walsnap)
if err != nil {
log.Fatal(err)
}
defer w.Close()
wmetadata, state, ents, err := w.ReadAll()
switch err {
case nil:
case wal.ErrSnapshotNotFound:
fmt.Printf("Failed to find the match snapshot record %+v in wal %v.", walsnap, srcWAL)
fmt.Printf("etcdctl will add it back. Start auto fixing...")
default:
log.Fatal(err)
}
var metadata etcdserverpb.Metadata
pbutil.MustUnmarshal(&metadata, wmetadata)
idgen := idutil.NewGenerator(0, time.Now())
metadata.NodeID = idgen.Next()
metadata.ClusterID = idgen.Next()
neww, err := wal.Create(destWAL, pbutil.MustMarshal(&metadata))
if err != nil {
log.Fatal(err)
}
defer neww.Close()
if err := neww.Save(state, ents); err != nil {
log.Fatal(err)
}
if err := neww.SaveSnapshot(walsnap); err != nil {
log.Fatal(err)
}
}
// Create returns a new WAL object with the given encrypters and decrypters.
func (wc walCryptor) Create(dirpath string, metadata []byte) (WAL, error) {
w, err := wal.Create(dirpath, metadata)
if err != nil {
return nil, err
}
return &wrappedWAL{
WAL: w,
encrypter: wc.encrypter,
decrypter: wc.decrypter,
}, nil
}
func (n *Node) loadAndStart(ctx context.Context, forceNewCluster bool) error {
walDir := n.walDir()
snapDir := n.snapDir()
if err := os.MkdirAll(snapDir, 0700); err != nil {
return fmt.Errorf("create snapshot directory error: %v", err)
}
// Create a snapshotter
n.snapshotter = snap.New(snapDir)
if !wal.Exist(walDir) {
raftNode := &api.RaftMember{
RaftID: n.Config.ID,
Addr: n.Address,
}
metadata, err := raftNode.Marshal()
if err != nil {
return fmt.Errorf("error marshalling raft node: %v", err)
}
n.wal, err = wal.Create(walDir, metadata)
if err != nil {
return fmt.Errorf("create wal error: %v", err)
}
n.cluster.AddMember(&membership.Member{RaftMember: raftNode})
n.startNodePeers = []raft.Peer{{ID: n.Config.ID, Context: metadata}}
return nil
}
// Load snapshot data
snapshot, err := n.snapshotter.Load()
if err != nil && err != snap.ErrNoSnapshot {
return err
}
if snapshot != nil {
// Load the snapshot data into the store
if err := n.restoreFromSnapshot(snapshot.Data, forceNewCluster); err != nil {
return err
}
}
// Read logs to fully catch up store
if err := n.readWAL(ctx, snapshot, forceNewCluster); err != nil {
return err
}
n.Node = raft.RestartNode(n.Config)
return nil
}
// makeWAL creates a WAL for the initial cluster
func makeWAL(waldir string, cl *membership.RaftCluster) {
if err := os.MkdirAll(waldir, 0755); err != nil {
ExitWithError(ExitIO, err)
}
m := cl.MemberByName(restoreName)
md := &etcdserverpb.Metadata{NodeID: uint64(m.ID), ClusterID: uint64(cl.ID())}
metadata, merr := md.Marshal()
if merr != nil {
ExitWithError(ExitInvalidInput, merr)
}
w, walerr := wal.Create(waldir, metadata)
if walerr != nil {
ExitWithError(ExitIO, walerr)
}
defer w.Close()
peers := make([]raft.Peer, len(cl.MemberIDs()))
for i, id := range cl.MemberIDs() {
ctx, err := json.Marshal((*cl).Member(id))
if err != nil {
ExitWithError(ExitInvalidInput, err)
}
peers[i] = raft.Peer{ID: uint64(id), Context: ctx}
}
ents := make([]raftpb.Entry, len(peers))
for i, p := range peers {
cc := raftpb.ConfChange{
Type: raftpb.ConfChangeAddNode,
NodeID: p.ID,
Context: p.Context}
d, err := cc.Marshal()
if err != nil {
ExitWithError(ExitInvalidInput, err)
}
e := raftpb.Entry{
Type: raftpb.EntryConfChange,
Term: 1,
Index: uint64(i + 1),
Data: d,
}
ents[i] = e
}
w.Save(raftpb.HardState{
Term: 1,
Vote: peers[0].ID,
Commit: uint64(len(ents))}, ents)
}
// handleBackup handles a request that intends to do a backup.
func handleBackup(c *cli.Context) {
srcSnap := path.Join(c.String("data-dir"), "snap")
destSnap := path.Join(c.String("backup-dir"), "snap")
srcWAL := path.Join(c.String("data-dir"), "wal")
destWAL := path.Join(c.String("backup-dir"), "wal")
if err := os.MkdirAll(destSnap, 0700); err != nil {
log.Fatalf("failed creating backup snapshot dir %v: %v", destSnap, err)
}
ss := snap.New(srcSnap)
snapshot, err := ss.Load()
if err != nil && err != snap.ErrNoSnapshot {
log.Fatal(err)
}
var index uint64
if snapshot != nil {
index = snapshot.Metadata.Index
newss := snap.New(destSnap)
if err := newss.SaveSnap(*snapshot); err != nil {
log.Fatal(err)
}
}
w, err := wal.OpenNotInUse(srcWAL, index)
if err != nil {
log.Fatal(err)
}
defer w.Close()
wmetadata, state, ents, err := w.ReadAll()
if err != nil {
log.Fatal(err)
}
var metadata etcdserverpb.Metadata
pbutil.MustUnmarshal(&metadata, wmetadata)
rand.Seed(time.Now().UnixNano())
metadata.NodeID = etcdserver.GenID()
metadata.ClusterID = etcdserver.GenID()
neww, err := wal.Create(destWAL, pbutil.MustMarshal(&metadata))
if err != nil {
log.Fatal(err)
}
defer neww.Close()
if err := neww.Save(state, ents); err != nil {
log.Fatal(err)
}
}
// handleBackup handles a request that intends to do a backup.
func handleBackup(c *cli.Context) {
srcSnap := path.Join(c.String("data-dir"), "snap")
destSnap := path.Join(c.String("backup-dir"), "snap")
srcWAL := path.Join(c.String("data-dir"), "wal")
destWAL := path.Join(c.String("backup-dir"), "wal")
if err := os.MkdirAll(destSnap, 0700); err != nil {
log.Fatalf("failed creating backup snapshot dir %v: %v", destSnap, err)
}
ss := snap.New(srcSnap)
snapshot, err := ss.Load()
if err != nil && err != snap.ErrNoSnapshot {
log.Fatal(err)
}
var walsnap walpb.Snapshot
if snapshot != nil {
walsnap.Index, walsnap.Term = snapshot.Metadata.Index, snapshot.Metadata.Term
newss := snap.New(destSnap)
if err := newss.SaveSnap(*snapshot); err != nil {
log.Fatal(err)
}
}
w, err := wal.OpenNotInUse(srcWAL, walsnap)
if err != nil {
log.Fatal(err)
}
defer w.Close()
wmetadata, state, ents, err := w.ReadAll()
if err != nil {
log.Fatal(err)
}
var metadata etcdserverpb.Metadata
pbutil.MustUnmarshal(&metadata, wmetadata)
idgen := idutil.NewGenerator(0, time.Now())
metadata.NodeID = idgen.Next()
metadata.ClusterID = idgen.Next()
neww, err := wal.Create(destWAL, pbutil.MustMarshal(&metadata))
if err != nil {
log.Fatal(err)
}
defer neww.Close()
if err := neww.Save(state, ents); err != nil {
log.Fatal(err)
}
}
func startNode(cfg *ServerConfig, cl *cluster, ids []types.ID) (id types.ID, n raft.Node, s *raft.MemoryStorage, w *wal.WAL) {
var err error
member := cl.MemberByName(cfg.Name)
metadata := pbutil.MustMarshal(
&pb.Metadata{
NodeID: uint64(member.ID),
ClusterID: uint64(cl.ID()),
},
)
//创建记录
if err = os.MkdirAll(cfg.SnapDir(), privateDirMode); err != nil {
plog.Fatalf("create snapshot directory error: %v", err)
}
if w, err = wal.Create(cfg.WALDir(), metadata); err != nil {
plog.Fatalf("create wal error: %v", err)
}
//获取节点信息
peers := make([]raft.Peer, len(ids))
for i, id := range ids {
ctx, err := json.Marshal((*cl).Member(id))
if err != nil {
plog.Panicf("marshal member should never fail: %v", err)
}
peers[i] = raft.Peer{ID: uint64(id), Context: ctx}
}
id = member.ID
plog.Infof("starting member %s in cluster %s", id, cl.ID())
s = raft.NewMemoryStorage()
c := &raft.Config{
ID: uint64(id),
ElectionTick: cfg.ElectionTicks,
HeartbeatTick: 1,
Storage: s, //存储
MaxSizePerMsg: maxSizePerMsg,
MaxInflightMsgs: maxInflightMsgs,
CheckQuorum: true,
}
n = raft.StartNode(c, peers)
raftStatusMu.Lock()
raftStatus = n.Status
raftStatusMu.Unlock()
advanceTicksForElection(n, c.ElectionTick)
return
}
func (n *Node) createWAL(nodeID string) (raft.Peer, error) {
raftNode := &api.RaftMember{
RaftID: n.Config.ID,
NodeID: nodeID,
Addr: n.Address,
}
metadata, err := raftNode.Marshal()
if err != nil {
return raft.Peer{}, fmt.Errorf("error marshalling raft node: %v", err)
}
n.wal, err = wal.Create(n.walDir(), metadata)
if err != nil {
return raft.Peer{}, fmt.Errorf("create WAL error: %v", err)
}
n.cluster.AddMember(&membership.Member{RaftMember: raftNode})
return raft.Peer{ID: n.Config.ID, Context: metadata}, nil
}
func (n *Node) createWAL(nodeID string) (raft.Peer, error) {
raftNode := &api.RaftMember{
RaftID: n.Config.ID,
NodeID: nodeID,
Addr: n.opts.Addr,
}
metadata, err := raftNode.Marshal()
if err != nil {
return raft.Peer{}, errors.Wrap(err, "error marshalling raft node")
}
n.wal, err = wal.Create(n.walDir(), metadata)
if err != nil {
return raft.Peer{}, errors.Wrap(err, "failed to create WAL")
}
n.cluster.AddMember(&membership.Member{RaftMember: raftNode})
return raft.Peer{ID: n.Config.ID, Context: metadata}, nil
}
// openWAL returns a WAL ready for reading.
func (rc *raftNode) openWAL() *wal.WAL {
if wal.Exist(rc.waldir) == false {
if err := os.Mkdir(rc.waldir, 0750); err != nil {
log.Fatalf("raftexample: cannot create dir for wal (%v)", err)
}
w, err := wal.Create(rc.waldir, nil)
if err != nil {
log.Fatalf("raftexample: create wal error (%v)", err)
}
w.Close()
}
w, err := wal.Open(rc.waldir, walpb.Snapshot{})
if err != nil {
log.Fatalf("raftexample: error loading wal (%v)", err)
}
return w
}
func startNode(cfg *ServerConfig, ids []uint64) (id uint64, n raft.Node, w *wal.WAL) {
var err error
// TODO: remove the discoveryURL when it becomes part of the source for
// generating nodeID.
member := cfg.Cluster.MemberByName(cfg.Name)
metadata := pbutil.MustMarshal(&pb.Metadata{NodeID: member.ID, ClusterID: cfg.Cluster.ID()})
if w, err = wal.Create(cfg.WALDir(), metadata); err != nil {
log.Fatal(err)
}
peers := make([]raft.Peer, len(ids))
for i, id := range ids {
ctx, err := json.Marshal((*cfg.Cluster).Member(id))
if err != nil {
log.Fatal(err)
}
peers[i] = raft.Peer{ID: id, Context: ctx}
}
id = member.ID
log.Printf("etcdserver: start node %x in cluster %x", id, cfg.Cluster.ID())
n = raft.StartNode(id, peers, 10, 1)
return
}
func main() {
flag.Parse()
if len(*migrateDatadir) == 0 {
glog.Fatal("need to set '--data-dir'")
}
dbpath := path.Join(*migrateDatadir, "member", "snap", "db")
// etcd3 store backend. We will use it to parse v3 data files and extract information.
be := backend.NewDefaultBackend(dbpath)
tx := be.BatchTx()
// etcd2 store backend. We will use v3 data to update this and then save snapshot to disk.
st := store.New(etcdserver.StoreClusterPrefix, etcdserver.StoreKeysPrefix)
expireTime := time.Now().Add(*ttl)
tx.Lock()
err := tx.UnsafeForEach([]byte("key"), func(k, v []byte) error {
kv := &mvccpb.KeyValue{}
kv.Unmarshal(v)
// This is compact key.
if !strings.HasPrefix(string(kv.Key), "/") {
return nil
}
ttlOpt := store.TTLOptionSet{}
if kv.Lease != 0 {
ttlOpt = store.TTLOptionSet{ExpireTime: expireTime}
}
if !isTombstone(k) {
sk := path.Join(strings.Trim(etcdserver.StoreKeysPrefix, "/"), string(kv.Key))
_, err := st.Set(sk, false, string(kv.Value), ttlOpt)
if err != nil {
return err
}
} else {
st.Delete(string(kv.Key), false, false)
}
return nil
})
if err != nil {
glog.Fatal(err)
}
tx.Unlock()
if err := traverseAndDeleteEmptyDir(st, "/"); err != nil {
glog.Fatal(err)
}
// rebuild cluster state.
metadata, hardstate, oldSt, err := rebuild(*migrateDatadir)
if err != nil {
glog.Fatal(err)
}
// In the following, it's low level logic that saves metadata and data into v2 snapshot.
backupPath := *migrateDatadir + ".rollback.backup"
if err := os.Rename(*migrateDatadir, backupPath); err != nil {
glog.Fatal(err)
}
if err := os.MkdirAll(path.Join(*migrateDatadir, "member", "snap"), 0700); err != nil {
glog.Fatal(err)
}
walDir := path.Join(*migrateDatadir, "member", "wal")
w, err := wal.Create(walDir, metadata)
if err != nil {
glog.Fatal(err)
}
err = w.SaveSnapshot(walpb.Snapshot{Index: hardstate.Commit, Term: hardstate.Term})
if err != nil {
glog.Fatal(err)
}
w.Close()
event, err := oldSt.Get(etcdserver.StoreClusterPrefix, true, false)
if err != nil {
glog.Fatal(err)
}
// nodes (members info) for ConfState
nodes := []uint64{}
traverseMetadata(event.Node, func(n *store.NodeExtern) {
if n.Key != etcdserver.StoreClusterPrefix {
// update store metadata
v := ""
if !n.Dir {
v = *n.Value
}
if n.Key == path.Join(etcdserver.StoreClusterPrefix, "version") {
v = rollbackVersion
}
if _, err := st.Set(n.Key, n.Dir, v, store.TTLOptionSet{}); err != nil {
glog.Fatal(err)
}
// update nodes
fields := strings.Split(n.Key, "/")
if len(fields) == 4 && fields[2] == "members" {
nodeID, err := strconv.ParseUint(fields[3], 16, 64)
if err != nil {
glog.Fatalf("failed to parse member ID (%s): %v", fields[3], err)
}
nodes = append(nodes, nodeID)
}
}
})
data, err := st.Save()
if err != nil {
glog.Fatal(err)
}
raftSnap := raftpb.Snapshot{
Data: data,
Metadata: raftpb.SnapshotMetadata{
Index: hardstate.Commit,
Term: hardstate.Term,
ConfState: raftpb.ConfState{
Nodes: nodes,
},
},
}
snapshotter := snap.New(path.Join(*migrateDatadir, "member", "snap"))
if err := snapshotter.SaveSnap(raftSnap); err != nil {
glog.Fatal(err)
}
fmt.Println("Finished successfully")
}
// makeWAL creates a WAL for the initial cluster
func makeWALAndSnap(waldir, snapdir string, cl *membership.RaftCluster) {
if err := fileutil.CreateDirAll(waldir); err != nil {
ExitWithError(ExitIO, err)
}
// add members again to persist them to the store we create.
st := store.New(etcdserver.StoreClusterPrefix, etcdserver.StoreKeysPrefix)
cl.SetStore(st)
for _, m := range cl.Members() {
cl.AddMember(m)
}
m := cl.MemberByName(restoreName)
md := &etcdserverpb.Metadata{NodeID: uint64(m.ID), ClusterID: uint64(cl.ID())}
metadata, merr := md.Marshal()
if merr != nil {
ExitWithError(ExitInvalidInput, merr)
}
w, walerr := wal.Create(waldir, metadata)
if walerr != nil {
ExitWithError(ExitIO, walerr)
}
defer w.Close()
peers := make([]raft.Peer, len(cl.MemberIDs()))
for i, id := range cl.MemberIDs() {
ctx, err := json.Marshal((*cl).Member(id))
if err != nil {
ExitWithError(ExitInvalidInput, err)
}
peers[i] = raft.Peer{ID: uint64(id), Context: ctx}
}
ents := make([]raftpb.Entry, len(peers))
nodeIDs := make([]uint64, len(peers))
for i, p := range peers {
nodeIDs[i] = p.ID
cc := raftpb.ConfChange{
Type: raftpb.ConfChangeAddNode,
NodeID: p.ID,
Context: p.Context}
d, err := cc.Marshal()
if err != nil {
ExitWithError(ExitInvalidInput, err)
}
e := raftpb.Entry{
Type: raftpb.EntryConfChange,
Term: 1,
Index: uint64(i + 1),
Data: d,
}
ents[i] = e
}
commit, term := uint64(len(ents)), uint64(1)
if err := w.Save(raftpb.HardState{
Term: term,
Vote: peers[0].ID,
Commit: commit}, ents); err != nil {
ExitWithError(ExitIO, err)
}
b, berr := st.Save()
if berr != nil {
ExitWithError(ExitError, berr)
}
raftSnap := raftpb.Snapshot{
Data: b,
Metadata: raftpb.SnapshotMetadata{
Index: commit,
Term: term,
ConfState: raftpb.ConfState{
Nodes: nodeIDs,
},
},
}
snapshotter := snap.New(snapdir)
if err := snapshotter.SaveSnap(raftSnap); err != nil {
panic(err)
}
if err := w.SaveSnapshot(walpb.Snapshot{Index: commit, Term: term}); err != nil {
ExitWithError(ExitIO, err)
}
}
// NewServer creates a new EtcdServer from the supplied configuration. The
// configuration is considered static for the lifetime of the EtcdServer.
func NewServer(cfg *ServerConfig) *EtcdServer {
m := cfg.Cluster.FindName(cfg.Name)
if m == nil {
// Should never happen
log.Fatalf("could not find name %v in cluster!", cfg.Name)
}
snapdir := path.Join(cfg.DataDir, "snap")
if err := os.MkdirAll(snapdir, privateDirMode); err != nil {
log.Fatalf("etcdserver: cannot create snapshot directory: %v", err)
}
ss := snap.New(snapdir)
st := store.New()
var w *wal.WAL
var n raft.Node
var err error
waldir := path.Join(cfg.DataDir, "wal")
if !wal.Exist(waldir) {
if w, err = wal.Create(waldir); err != nil {
log.Fatal(err)
}
n = raft.StartNode(m.ID, cfg.Cluster.IDs(), 10, 1)
} else {
var index int64
snapshot, err := ss.Load()
if err != nil && err != snap.ErrNoSnapshot {
log.Fatal(err)
}
if snapshot != nil {
log.Printf("etcdserver: restart from snapshot at index %d", snapshot.Index)
st.Recovery(snapshot.Data)
index = snapshot.Index
}
// restart a node from previous wal
if w, err = wal.OpenAtIndex(waldir, index); err != nil {
log.Fatal(err)
}
wid, st, ents, err := w.ReadAll()
if err != nil {
log.Fatal(err)
}
// TODO(xiangli): save/recovery nodeID?
if wid != 0 {
log.Fatalf("unexpected nodeid %d: nodeid should always be zero until we save nodeid into wal", wid)
}
n = raft.RestartNode(m.ID, cfg.Cluster.IDs(), 10, 1, snapshot, st, ents)
}
cls := NewClusterStore(st, *cfg.Cluster)
s := &EtcdServer{
store: st,
node: n,
name: cfg.Name,
storage: struct {
*wal.WAL
*snap.Snapshotter
}{w, ss},
send: Sender(cfg.Transport, cls),
clientURLs: cfg.ClientURLs,
ticker: time.Tick(100 * time.Millisecond),
syncTicker: time.Tick(500 * time.Millisecond),
snapCount: cfg.SnapCount,
ClusterStore: cls,
}
return s
}
func Migrate4To5(dataDir string, name string) error {
// prep new directories
sd5 := snapDir5(dataDir)
if err := os.MkdirAll(sd5, 0700); err != nil {
return fmt.Errorf("failed creating snapshot directory %s: %v", sd5, err)
}
// read v0.4 data
snap4, err := DecodeLatestSnapshot4FromDir(snapDir4(dataDir))
if err != nil {
return err
}
cfg4, err := DecodeConfig4FromFile(cfgFile4(dataDir))
if err != nil {
return err
}
ents4, err := DecodeLog4FromFile(logFile4(dataDir))
if err != nil {
return err
}
nodeIDs := ents4.NodeIDs()
nodeID := GuessNodeID(nodeIDs, snap4, cfg4, name)
if nodeID == 0 {
return fmt.Errorf("Couldn't figure out the node ID from the log or flags, cannot convert")
}
metadata := pbutil.MustMarshal(&pb.Metadata{NodeID: nodeID, ClusterID: 0x04add5})
wd5 := walDir5(dataDir)
w, err := wal.Create(wd5, metadata)
if err != nil {
return fmt.Errorf("failed initializing wal at %s: %v", wd5, err)
}
defer w.Close()
// transform v0.4 data
var snap5 *raftpb.Snapshot
if snap4 == nil {
log.Printf("No snapshot found")
} else {
log.Printf("Found snapshot: lastIndex=%d", snap4.LastIndex)
snap5 = snap4.Snapshot5()
}
st5 := cfg4.HardState5()
// If we've got the most recent snapshot, we can use it's committed index. Still likely less than the current actual index, but worth it for the replay.
if snap5 != nil {
st5.Commit = snap5.Metadata.Index
}
ents5, err := Entries4To5(ents4)
if err != nil {
return err
}
ents5Len := len(ents5)
log.Printf("Found %d log entries: firstIndex=%d lastIndex=%d", ents5Len, ents5[0].Index, ents5[ents5Len-1].Index)
// explicitly prepend an empty entry as the WAL code expects it
ents5 = append(make([]raftpb.Entry, 1), ents5...)
if err = w.Save(st5, ents5); err != nil {
return err
}
log.Printf("Log migration successful")
// migrate snapshot (if necessary) and logs
if snap5 != nil {
ss := snap.New(sd5)
if err := ss.SaveSnap(*snap5); err != nil {
return err
}
log.Printf("Snapshot migration successful")
}
return nil
}
func (o originalWAL) Create(dirpath string, metadata []byte) (WAL, error) {
return wal.Create(dirpath, metadata)
}
func Migrate4To2(dataDir string, name string) error {
// prep new directories
sd2 := snapDir2(dataDir)
if err := os.MkdirAll(sd2, 0700); err != nil {
return fmt.Errorf("failed creating snapshot directory %s: %v", sd2, err)
}
// read v0.4 data
snap4, err := DecodeLatestSnapshot4FromDir(snapDir4(dataDir))
if err != nil {
return err
}
cfg4, err := DecodeConfig4FromFile(cfgFile4(dataDir))
if err != nil {
return err
}
ents4, err := DecodeLog4FromFile(logFile4(dataDir))
if err != nil {
return err
}
nodeIDs := ents4.NodeIDs()
nodeID := GuessNodeID(nodeIDs, snap4, cfg4, name)
if nodeID == 0 {
return fmt.Errorf("Couldn't figure out the node ID from the log or flags, cannot convert")
}
metadata := pbutil.MustMarshal(&pb.Metadata{NodeID: nodeID, ClusterID: 0x04add5})
wd2 := walDir2(dataDir)
w, err := wal.Create(wd2, metadata)
if err != nil {
return fmt.Errorf("failed initializing wal at %s: %v", wd2, err)
}
defer w.Close()
// transform v0.4 data
var snap2 *raftpb.Snapshot
if snap4 == nil {
log.Printf("No snapshot found")
} else {
log.Printf("Found snapshot: lastIndex=%d", snap4.LastIndex)
snap2 = snap4.Snapshot2()
}
st2 := cfg4.HardState2()
// If we've got the most recent snapshot, we can use it's committed index. Still likely less than the current actual index, but worth it for the replay.
if snap2 != nil {
st2.Commit = snap2.Metadata.Index
}
ents2, err := Entries4To2(ents4)
if err != nil {
return err
}
ents2Len := len(ents2)
log.Printf("Found %d log entries: firstIndex=%d lastIndex=%d", ents2Len, ents2[0].Index, ents2[ents2Len-1].Index)
// set the state term to the biggest term we have ever seen,
// so term of future entries will not be the same with term of old ones.
st2.Term = ents2[ents2Len-1].Term
// explicitly prepend an empty entry as the WAL code expects it
ents2 = append(make([]raftpb.Entry, 1), ents2...)
if err = w.Save(st2, ents2); err != nil {
return err
}
log.Printf("Log migration successful")
// migrate snapshot (if necessary) and logs
var walsnap walpb.Snapshot
if snap2 != nil {
walsnap.Index, walsnap.Term = snap2.Metadata.Index, snap2.Metadata.Term
ss := snap.New(sd2)
if err := ss.SaveSnap(*snap2); err != nil {
return err
}
log.Printf("Snapshot migration successful")
}
if err = w.SaveSnapshot(walsnap); err != nil {
return err
}
return nil
}