leveldb2: support subscribing from peers

weed/filer2/leveldb2/leveldb2_local_store.go

@@ -0,0 +1,47 @@
+package leveldb
+
+import (
+	"fmt"
+
+	"github.com/chrislusf/seaweedfs/weed/filer2"
+	"github.com/chrislusf/seaweedfs/weed/util"
+)
+
+func init() {
+	filer2.Stores = append(filer2.Stores, &LevelDB2Store{})
+}
+
+var (
+	_ = filer2.FilerLocalStore(&LevelDB2Store{})
+)
+
+func (store *LevelDB2Store) UpdateOffset(filer string, lastTsNs int64) error {
+
+	value := make([]byte, 8)
+	util.Uint64toBytes(value, uint64(lastTsNs))
+
+	err := store.dbs[0].Put([]byte("meta"+filer), value, nil)
+
+	if err != nil {
+		return fmt.Errorf("UpdateOffset %s : %v", filer, err)
+	}
+
+	println("UpdateOffset", filer, "lastTsNs", lastTsNs)
+
+	return nil
+}
+
+func (store *LevelDB2Store) ReadOffset(filer string) (lastTsNs int64, err error) {
+
+	value, err := store.dbs[0].Get([]byte("meta"+filer), nil)
+
+	if err != nil {
+		return 0, fmt.Errorf("ReadOffset %s : %v", filer, err)
+	}
+
+	lastTsNs = int64(util.BytesToUint64(value))
+
+	println("ReadOffset", filer, "lastTsNs", lastTsNs)
+
+	return
+}