func (s *store) put(key, value []byte) {
rev := s.currentRev.main + 1
c := rev
// if the key exists before, use its previous created
_, created, ver, err := s.kvindex.Get(key, rev)
if err == nil {
c = created.main
}
ibytes := newRevBytes()
revToBytes(revision{main: rev, sub: s.currentRev.sub}, ibytes)
ver = ver + 1
event := storagepb.Event{
Type: storagepb.PUT,
Kv: &storagepb.KeyValue{
Key: key,
Value: value,
CreateRevision: c,
ModRevision: rev,
Version: ver,
},
}
d, err := event.Marshal()
if err != nil {
log.Fatalf("storage: cannot marshal event: %v", err)
}
s.tx.UnsafePut(keyBucketName, ibytes, d)
s.kvindex.Put(key, revision{main: rev, sub: s.currentRev.sub})
s.currentRev.sub += 1
}
func (s *store) delete(key []byte) {
mainrev := s.currentRev.main + 1
ibytes := newRevBytes()
revToBytes(revision{main: mainrev, sub: s.currentRev.sub}, ibytes)
event := storagepb.Event{
Type: storagepb.DELETE,
Kv: &storagepb.KeyValue{
Key: key,
},
}
d, err := event.Marshal()
if err != nil {
log.Fatalf("storage: cannot marshal event: %v", err)
}
s.tx.UnsafePut(keyBucketName, ibytes, d)
err = s.kvindex.Tombstone(key, revision{main: mainrev, sub: s.currentRev.sub})
if err != nil {
log.Fatalf("storage: cannot tombstone an existing key (%s): %v", string(key), err)
}
s.currentRev.sub += 1
}
// RangeEvents gets the events from key to end in [startRev, endRev).
// If `end` is nil, the request only observes the events on key.
// If `end` is not nil, it observes the events on key range [key, range_end).
// Limit limits the number of events returned.
// If startRev <=0, rangeEvents returns events from the beginning of uncompacted history.
// If endRev <=0, it indicates there is no end revision.
//
// If the required start rev is compacted, ErrCompacted will be returned.
// If the required start rev has not happened, ErrFutureRev will be returned.
//
// RangeEvents returns events that satisfy the requirement (0 <= n <= limit).
// If events in the revision range have not all happened, it returns immeidately
// what is available.
// It also returns nextRev which indicates the start revision used for the following
// RangeEvents call. The nextRev could be smaller than the given endRev if the store
// has not progressed so far or it hits the event limit.
//
// TODO: return byte slices instead of events to avoid meaningless encode and decode.
func (s *store) RangeEvents(key, end []byte, limit, startRev, endRev int64) (evs []storagepb.Event, nextRev int64, err error) {
s.mu.Lock()
defer s.mu.Unlock()
if startRev > 0 && startRev <= s.compactMainRev {
return nil, 0, ErrCompacted
}
if startRev > s.currentRev.main {
return nil, 0, ErrFutureRev
}
revs := s.kvindex.RangeEvents(key, end, startRev)
if len(revs) == 0 {
return nil, s.currentRev.main + 1, nil
}
tx := s.b.BatchTx()
tx.Lock()
defer tx.Unlock()
// fetch events from the backend using revisions
for _, rev := range revs {
if endRev > 0 && rev.main >= endRev {
return evs, rev.main, nil
}
revbytes := newRevBytes()
revToBytes(rev, revbytes)
_, vs := tx.UnsafeRange(keyBucketName, revbytes, nil, 0)
if len(vs) != 1 {
log.Fatalf("storage: range cannot find rev (%d,%d)", rev.main, rev.sub)
}
e := storagepb.Event{}
if err := e.Unmarshal(vs[0]); err != nil {
log.Fatalf("storage: cannot unmarshal event: %v", err)
}
evs = append(evs, e)
if limit > 0 && len(evs) >= int(limit) {
return evs, rev.main + 1, nil
}
}
return evs, s.currentRev.main + 1, nil
}
func TestStoreRestore(t *testing.T) {
s, b, index := newFakeStore()
putev := storagepb.Event{
Type: storagepb.PUT,
Kv: &storagepb.KeyValue{
Key: []byte("foo"),
Value: []byte("bar"),
CreateRevision: 3,
ModRevision: 3,
Version: 1,
},
}
putevb, err := putev.Marshal()
if err != nil {
t.Fatal(err)
}
delev := storagepb.Event{
Type: storagepb.DELETE,
Kv: &storagepb.KeyValue{
Key: []byte("foo"),
},
}
delevb, err := delev.Marshal()
if err != nil {
t.Fatal(err)
}
b.tx.rangeRespc <- rangeResp{[][]byte{finishedCompactKeyName}, [][]byte{newTestBytes(revision{2, 0})}}
b.tx.rangeRespc <- rangeResp{[][]byte{newTestBytes(revision{3, 0}), newTestBytes(revision{4, 0})}, [][]byte{putevb, delevb}}
b.tx.rangeRespc <- rangeResp{[][]byte{scheduledCompactKeyName}, [][]byte{newTestBytes(revision{2, 0})}}
s.Restore()
if s.compactMainRev != 2 {
t.Errorf("compact rev = %d, want 4", s.compactMainRev)
}
wrev := revision{4, 0}
if !reflect.DeepEqual(s.currentRev, wrev) {
t.Errorf("current rev = %v, want %v", s.currentRev, wrev)
}
wact := []testutil.Action{
{"range", []interface{}{metaBucketName, finishedCompactKeyName, []byte(nil), int64(0)}},
{"range", []interface{}{keyBucketName, newTestBytes(revision{}), newTestBytes(revision{math.MaxInt64, math.MaxInt64}), int64(0)}},
{"range", []interface{}{metaBucketName, scheduledCompactKeyName, []byte(nil), int64(0)}},
}
if g := b.tx.Action(); !reflect.DeepEqual(g, wact) {
t.Errorf("tx actions = %+v, want %+v", g, wact)
}
wact = []testutil.Action{
{"restore", []interface{}{[]byte("foo"), revision{3, 0}, revision{3, 0}, int64(1)}},
{"tombstone", []interface{}{[]byte("foo"), revision{4, 0}}},
}
if g := index.Action(); !reflect.DeepEqual(g, wact) {
t.Errorf("index action = %+v, want %+v", g, wact)
}
}
func TestStoreRangeEvents(t *testing.T) {
ev := storagepb.Event{
Type: storagepb.PUT,
Kv: &storagepb.KeyValue{
Key: []byte("foo"),
Value: []byte("bar"),
CreateRevision: 1,
ModRevision: 2,
Version: 1,
},
}
evb, err := ev.Marshal()
if err != nil {
t.Fatal(err)
}
currev := revision{2, 0}
tests := []struct {
idxr indexRangeEventsResp
r rangeResp
}{
{
indexRangeEventsResp{[]revision{{2, 0}}},
rangeResp{[][]byte{newTestBytes(revision{2, 0})}, [][]byte{evb}},
},
{
indexRangeEventsResp{[]revision{{2, 0}, {3, 0}}},
rangeResp{[][]byte{newTestBytes(revision{2, 0})}, [][]byte{evb}},
},
}
for i, tt := range tests {
s, b, index := newFakeStore()
s.currentRev = currev
index.indexRangeEventsRespc <- tt.idxr
b.tx.rangeRespc <- tt.r
evs, _, err := s.RangeEvents([]byte("foo"), []byte("goo"), 1, 1, 4)
if err != nil {
t.Errorf("#%d: err = %v, want nil", i, err)
}
if w := []storagepb.Event{ev}; !reflect.DeepEqual(evs, w) {
t.Errorf("#%d: evs = %+v, want %+v", i, evs, w)
}
wact := []testutil.Action{
{"rangeEvents", []interface{}{[]byte("foo"), []byte("goo"), int64(1)}},
}
if g := index.Action(); !reflect.DeepEqual(g, wact) {
t.Errorf("#%d: index action = %+v, want %+v", i, g, wact)
}
wact = []testutil.Action{
{"range", []interface{}{keyBucketName, newTestBytes(tt.idxr.revs[0]), []byte(nil), int64(0)}},
}
if g := b.tx.Action(); !reflect.DeepEqual(g, wact) {
t.Errorf("#%d: tx action = %+v, want %+v", i, g, wact)
}
if s.currentRev != currev {
t.Errorf("#%d: current rev = %+v, want %+v", i, s.currentRev, currev)
}
}
}