Mirroristas/etcd
2
0
Fork 0
mirror of https://github.com/etcd-io/etcd.git synced 2024-09-27 06:25:44 +00:00
Code Issues Packages Projects Releases Wiki Activity

wal: save latest state into new WAL

Browse Source 
So we could always read out state when open at valid index.
This commit is contained in:
Yicheng Qin 2014-12-02 23:35:44 -08:00
parent 23b32a6cbe
commit af0f34c595
2 changed files with 31 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
wal/wal.go
View File

@ -56,8 +56,9 @@ var (
// A just opened WAL is in read mode, and ready for reading records. // A just opened WAL is in read mode, and ready for reading records.
// The WAL will be ready for appending after reading out all the previous records. // The WAL will be ready for appending after reading out all the previous records.
type WAL struct { type WAL struct {
dir string // the living directory of the underlay files dir string // the living directory of the underlay files
metadata []byte // metadata recorded at the head of each WAL metadata []byte // metadata recorded at the head of each WAL
state raftpb.HardState // hardstate recorded at the head of WAL
ri uint64 // index of entry to start reading ri uint64 // index of entry to start reading
decoder *decoder // decoder to decode records decoder *decoder // decoder to decode records
@ -236,7 +237,10 @@ func (w *WAL) Cut() error {
if err := w.saveCrc(prevCrc); err != nil { if err := w.saveCrc(prevCrc); err != nil {
return err return err
} }
return w.encoder.encode(&walpb.Record{Type: metadataType, Data: w.metadata}) if err := w.encoder.encode(&walpb.Record{Type: metadataType, Data: w.metadata}); err != nil {
return err
}
return w.SaveState(&w.state)
} }
func (w *WAL) sync() error { func (w *WAL) sync() error {
@ -274,6 +278,7 @@ func (w *WAL) SaveState(s *raftpb.HardState) error {
if raft.IsEmptyHardState(*s) { if raft.IsEmptyHardState(*s) {
return nil return nil
} }
w.state = *s
b := pbutil.MustMarshal(s) b := pbutil.MustMarshal(s)
rec := &walpb.Record{Type: stateType, Data: b} rec := &walpb.Record{Type: stateType, Data: b}
return w.encoder.encode(rec) return w.encoder.encode(rec)

24
wal/wal_test.go
View File

@ -142,12 +142,15 @@ func TestCut(t *testing.T) {
if err != nil { if err != nil {
t.Fatal(err) t.Fatal(err)
} }
defer w.Close()
// TODO(unihorn): remove this when cut can operate on an empty file // TODO(unihorn): remove this when cut can operate on an empty file
if err := w.SaveEntry(&raftpb.Entry{}); err != nil { if err := w.SaveEntry(&raftpb.Entry{}); err != nil {
t.Fatal(err) t.Fatal(err)
} }
state := raftpb.HardState{Term: 1}
if err := w.SaveState(&state); err != nil {
t.Fatal(err)
}
if err := w.Cut(); err != nil { if err := w.Cut(); err != nil {
t.Fatal(err) t.Fatal(err)
} }
@ -167,6 +170,25 @@ func TestCut(t *testing.T) {
if g := path.Base(w.f.Name()); g != wname { if g := path.Base(w.f.Name()); g != wname {
t.Errorf("name = %s, want %s", g, wname) t.Errorf("name = %s, want %s", g, wname)
} }
w.Close()
// check the state in the last WAL
f, err := os.Open(path.Join(p, wname))
if err != nil {
t.Fatal(err)
}
defer f.Close()
w = &WAL{
decoder: newDecoder(f),
ri: 2,
}
_, gst, _, err := w.ReadAll()
if err != nil {
t.Fatal(err)
}
if !reflect.DeepEqual(gst, state) {
t.Errorf("state = %+v, want %+v", gst, state)
}
} }
func TestRecover(t *testing.T) { func TestRecover(t *testing.T) {