go-ethereum/swarm/network/stream/intervals/dbstore.go
2018-02-14 14:24:57 +01:00

78 lines
2.1 KiB
Go

// Copyright 2018 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package intervals
import (
"github.com/syndtr/goleveldb/leveldb"
)
// DBStore uses LevelDB to store intervals.
type DBStore struct {
db *leveldb.DB
}
// NewDBStore creates a new instance of DBStore.
func NewDBStore(path string) (s *DBStore, err error) {
db, err := leveldb.OpenFile(path, nil)
if err != nil {
return nil, err
}
return &DBStore{
db: db,
}, nil
}
// Get retrieves Intervals for a specific key. If there is no Intervals
// ErrNotFound is returned.
func (s *DBStore) Get(key string) (i *Intervals, err error) {
k := []byte(key)
has, err := s.db.Has(k, nil)
if err != nil {
return nil, ErrNotFound
}
if !has {
return nil, ErrNotFound
}
data, err := s.db.Get(k, nil)
if err == leveldb.ErrNotFound {
err = ErrNotFound
}
i = &Intervals{}
if err = i.UnmarshalBinary(data); err != nil {
return nil, err
}
return i, err
}
// Put stores Intervals for a specific key.
func (s *DBStore) Put(key string, i *Intervals) (err error) {
data, err := i.MarshalBinary()
if err != nil {
return err
}
return s.db.Put([]byte(key), data, nil)
}
// Delete removes Intervals stored under a specific key.
func (s *DBStore) Delete(key string) (err error) {
return s.db.Delete([]byte(key), nil)
}
// Close releases the resources used by the underlying LevelDB.
func (s *DBStore) Close() error {
return s.db.Close()
}