Add badger to db backend

manager/db_badger.go

@@ -0,0 +1,67 @@
+package manager
+
+import (
+	"github.com/dgraph-io/badger/v2"
+)
+
+// implement kv interface backed by badger
+type badgerAdapter struct {
+	db *badger.DB
+}
+
+func (b *badgerAdapter) InitBucket(bucket string) (err error) {
+	// no-op
+	return
+}
+
+func (b *badgerAdapter) Get(bucket string, key string) (v []byte, err error) {
+	b.db.View(func(tx *badger.Txn) error {
+		var item *badger.Item
+		item, err = tx.Get([]byte(bucket + key))
+		if item != nil {
+			v, err = item.ValueCopy(nil)
+		}
+		return nil
+	})
+	return
+}
+
+func (b *badgerAdapter) GetAll(bucket string) (m map[string][]byte, err error) {
+	b.db.View(func(tx *badger.Txn) error {
+		it := tx.NewIterator(badger.DefaultIteratorOptions)
+		defer it.Close()
+		prefix := []byte(bucket)
+		m = make(map[string][]byte)
+		for it.Seek(prefix); it.ValidForPrefix(prefix); it.Next() {
+			item := it.Item()
+			k := string(item.Key())
+			actualKey := k[len(bucket):]
+
+			var v []byte
+			v, err = item.ValueCopy(nil)
+			m[actualKey] = v
+		}
+		return nil
+	})
+	return
+}
+
+func (b *badgerAdapter) Put(bucket string, key string, value []byte) error {
+	err := b.db.Update(func(tx *badger.Txn) error {
+		err := tx.Set([]byte(bucket+key), value)
+		return err
+	})
+	return err
+}
+
+func (b *badgerAdapter) Delete(bucket string, key string) error {
+	err := b.db.Update(func(tx *badger.Txn) error {
+		err := tx.Delete([]byte(bucket + key))
+		return err
+	})
+	return err
+}
+
+func (b *badgerAdapter) Close() error {
+	return b.db.Close()
+}