add sync interface

store/boltdb/db.go

@@ -98,7 +98,14 @@ func (db *DB) Delete(key []byte) error {
 		return b.Delete(key)
 	})
 	return err
+}
 
+func (db *DB) SyncPut(key []byte, value []byte) error {
+	return db.Put(key, value)
+}
+
+func (db *DB) SyncDelete(key []byte) error {
+	return db.Delete(key)
 }
 
 func (db *DB) NewIterator() driver.IIterator {
@@ -152,6 +159,10 @@ func (db *DB) BatchPut(writes []driver.Write) error {
 	return err
 }
 
+func (db *DB) SyncBatchPut(writes []driver.Write) error {
+	return db.BatchPut(writes)
+}
+
 func (db *DB) Compact() error {
 	return nil
 }

store/boltdb/tx.go

@@ -48,6 +48,10 @@ func (t *Tx) BatchPut(writes []driver.Write) error {
 	return nil
 }
 
+func (t *Tx) SyncBatchPut(writes []driver.Write) error {
+	return t.BatchPut(writes)
+}
+
 func (t *Tx) Rollback() error {
 	return t.tx.Rollback()
 }

store/driver/batch.go

@@ -2,6 +2,7 @@ package driver
 
 type BatchPuter interface {
 	BatchPut([]Write) error
+	SyncBatchPut([]Write) error
 }
 
 type Write struct {
@@ -29,6 +30,10 @@ func (w *WriteBatch) Commit() error {
 	return w.batch.BatchPut(w.wb)
 }
 
+func (w *WriteBatch) SyncCommit() error {
+	return w.batch.SyncBatchPut(w.wb)
+}
+
 func (w *WriteBatch) Rollback() error {
 	w.wb = w.wb[0:0]
 	return nil

store/driver/driver.go

@@ -16,6 +16,9 @@ type IDB interface {
 	Put(key []byte, value []byte) error
 	Delete(key []byte) error
 
+	SyncPut(key []byte, value []byte) error
+	SyncDelete(key []byte) error
+
 	NewIterator() IIterator
 
 	NewWriteBatch() IWriteBatch
@@ -53,6 +56,7 @@ type IWriteBatch interface {
 	Put(key []byte, value []byte)
 	Delete(key []byte)
 	Commit() error
+	SyncCommit() error
 	Rollback() error
 }
 

store/goleveldb/batch.go

@@ -21,6 +21,10 @@ func (w *WriteBatch) Commit() error {
 	return w.db.db.Write(w.wbatch, nil)
 }
 
+func (w *WriteBatch) SyncCommit() error {
+	return w.db.db.Write(w.wbatch, w.db.syncOpts)
+}
+
 func (w *WriteBatch) Rollback() error {
 	w.wbatch.Reset()
 	return nil

store/goleveldb/db.go

@@ -41,6 +41,8 @@ type DB struct {
 
 	iteratorOpts *opt.ReadOptions
 
+	syncOpts *opt.WriteOptions
+
 	cache cache.Cache
 
 	filter filter.Filter
@@ -102,6 +104,9 @@ func (db *DB) initOpts() {
 
 	db.iteratorOpts = &opt.ReadOptions{}
 	db.iteratorOpts.DontFillCache = true
+
+	db.syncOpts = &opt.WriteOptions{}
+	db.syncOpts.Sync = true
 }
 
 func newOptions(cfg *config.LevelDBConfig) *opt.Options {
@@ -147,6 +152,14 @@ func (db *DB) Delete(key []byte) error {
 	return db.db.Delete(key, nil)
 }
 
+func (db *DB) SyncPut(key []byte, value []byte) error {
+	return db.db.Put(key, value, db.syncOpts)
+}
+
+func (db *DB) SyncDelete(key []byte) error {
+	return db.db.Delete(key, db.syncOpts)
+}
+
 func (db *DB) NewWriteBatch() driver.IWriteBatch {
 	wb := &WriteBatch{
 		db:     db,

store/hyperleveldb/batch.go

@@ -46,6 +46,10 @@ func (w *WriteBatch) Commit() error {
 	return w.commit(w.db.writeOpts)
 }
 
+func (w *WriteBatch) SyncCommit() error {
+	return w.commit(w.db.syncOpts)
+}
+
 func (w *WriteBatch) Rollback() error {
 	C.leveldb_writebatch_clear(w.wbatch)
 	return nil

store/hyperleveldb/db.go

@@ -81,6 +81,8 @@ type DB struct {
 	writeOpts    *WriteOptions
 	iteratorOpts *ReadOptions
 
+	syncOpts *WriteOptions
+
 	cache *Cache
 
 	filter *FilterPolicy
@@ -132,6 +134,9 @@ func (db *DB) initOptions(cfg *config.LevelDBConfig) {
 	db.readOpts = NewReadOptions()
 	db.writeOpts = NewWriteOptions()
 
+	db.syncOpts = NewWriteOptions()
+	db.syncOpts.SetSync(true)
+
 	db.iteratorOpts = NewReadOptions()
 	db.iteratorOpts.SetFillCache(false)
 }
@@ -171,6 +176,14 @@ func (db *DB) Delete(key []byte) error {
 	return db.delete(db.writeOpts, key)
 }
 
+func (db *DB) SyncPut(key []byte, value []byte) error {
+	return db.put(db.syncOpts, key, value)
+}
+
+func (db *DB) SyncDelete(key []byte) error {
+	return db.delete(db.syncOpts, key)
+}
+
 func (db *DB) NewWriteBatch() driver.IWriteBatch {
 	wb := &WriteBatch{
 		db:     db,

store/leveldb/batch.go

@@ -46,6 +46,10 @@ func (w *WriteBatch) Commit() error {
 	return w.commit(w.db.writeOpts)
 }
 
+func (w *WriteBatch) SyncCommit() error {
+	return w.commit(w.db.syncOpts)
+}
+
 func (w *WriteBatch) Rollback() error {
 	C.leveldb_writebatch_clear(w.wbatch)
 	return nil

store/leveldb/db.go

@@ -81,6 +81,8 @@ type DB struct {
 	writeOpts    *WriteOptions
 	iteratorOpts *ReadOptions
 
+	syncOpts *WriteOptions
+
 	cache *Cache
 
 	filter *FilterPolicy
@@ -132,6 +134,9 @@ func (db *DB) initOptions(cfg *config.LevelDBConfig) {
 	db.readOpts = NewReadOptions()
 	db.writeOpts = NewWriteOptions()
 
+	db.syncOpts = NewWriteOptions()
+	db.syncOpts.SetSync(true)
+
 	db.iteratorOpts = NewReadOptions()
 	db.iteratorOpts.SetFillCache(false)
 }
@@ -171,6 +176,14 @@ func (db *DB) Delete(key []byte) error {
 	return db.delete(db.writeOpts, key)
 }
 
+func (db *DB) SyncPut(key []byte, value []byte) error {
+	return db.put(db.syncOpts, key, value)
+}
+
+func (db *DB) SyncDelete(key []byte) error {
+	return db.delete(db.syncOpts, key)
+}
+
 func (db *DB) NewWriteBatch() driver.IWriteBatch {
 	wb := &WriteBatch{
 		db:     db,

store/mdb/mdb.go

@@ -122,6 +122,14 @@ func (db MDB) BatchPut(writes []driver.Write) error {
 	return itr.err
 }
 
+func (db MDB) SyncBatchPut(writes []driver.Write) error {
+	if err := db.BatchPut(writes); err != nil {
+		return err
+	}
+
+	return db.env.Sync(1)
+}
+
 func (db MDB) Get(key []byte) ([]byte, error) {
 	tx, err := db.env.BeginTxn(nil, mdb.RDONLY)
 	if err != nil {
@@ -148,6 +156,22 @@ func (db MDB) Delete(key []byte) error {
 	return itr.Error()
 }
 
+func (db MDB) SyncPut(key []byte, value []byte) error {
+	if err := db.Put(key, value); err != nil {
+		return err
+	}
+
+	return db.env.Sync(1)
+}
+
+func (db MDB) SyncDelete(key []byte) error {
+	if err := db.Delete(key); err != nil {
+		return err
+	}
+
+	return db.env.Sync(1)
+}
+
 type MDBIterator struct {
 	key   []byte
 	value []byte

store/mdb/tx.go

@@ -74,7 +74,10 @@ func (t *Tx) BatchPut(writes []driver.Write) error {
 	itr.setState()
 
 	return itr.Close()
+}
 
+func (t *Tx) SyncBatchPut(writes []driver.Write) error {
+	return t.BatchPut(writes)
 }
 
 func (t *Tx) Rollback() error {

store/rocksdb/batch.go

@@ -45,6 +45,10 @@ func (w *WriteBatch) Commit() error {
 	return w.commit(w.db.writeOpts)
 }
 
+func (w *WriteBatch) SyncCommit() error {
+	return w.commit(w.db.syncOpts)
+}
+
 func (w *WriteBatch) Rollback() error {
 	C.rocksdb_writebatch_clear(w.wbatch)
 	return nil

store/rocksdb/db.go

@@ -85,6 +85,8 @@ type DB struct {
 	writeOpts    *WriteOptions
 	iteratorOpts *ReadOptions
 
+	syncOpts *WriteOptions
+
 	cache *Cache
 
 	filter *FilterPolicy
@@ -152,6 +154,9 @@ func (db *DB) initOptions(cfg *config.LevelDBConfig) {
 	db.readOpts = NewReadOptions()
 	db.writeOpts = NewWriteOptions()
 
+	db.syncOpts = NewWriteOptions()
+	db.syncOpts.SetSync(true)
+
 	db.iteratorOpts = NewReadOptions()
 	db.iteratorOpts.SetFillCache(false)
 }
@@ -197,6 +202,14 @@ func (db *DB) Delete(key []byte) error {
 	return db.delete(db.writeOpts, key)
 }
 
+func (db *DB) SyncPut(key []byte, value []byte) error {
+	return db.put(db.syncOpts, key, value)
+}
+
+func (db *DB) SyncDelete(key []byte) error {
+	return db.delete(db.syncOpts, key)
+}
+
 func (db *DB) NewWriteBatch() driver.IWriteBatch {
 	wb := &WriteBatch{
 		db:     db,