Exemple #1
0
// UpdateValueKeyBy ??
func (qs *QuadStore) UpdateValueKeyBy(name string, amount int64, tx *lmdb.Txn) error {
	value := proto.NodeData{
		Name:  name,
		Size_: amount,
	}
	key := qs.createValueKeyFor(name)
	data, err := tx.Get(qs.nodeDBI, key)
	if err == nil {
		// Node exists in the database -- unmarshal and update.
		var oldvalue proto.NodeData
		err := oldvalue.Unmarshal(data)
		if err != nil {
			glog.Errorf("Error: couldn't reconstruct value: %v", err)
			return err
		}
		oldvalue.Size_ += amount
		value = oldvalue
	}

	// Are we deleting something?
	if value.Size_ <= 0 {
		value.Size_ = 0
	}

	// Repackage and rewrite.
	bytes, err := value.Marshal()
	if err != nil {
		glog.Errorf("Couldn't write to buffer for value %s: %s", name, err)
		return err
	}
	err = tx.Put(qs.nodeDBI, key, bytes, 0)
	return err
}
Exemple #2
0
func (qs *QuadStore) getInt64ForMetaKey(tx *lmdb.Txn, key string, empty int64) (int64, error) {
	var out int64
	data, err := tx.Get(qs.metaDBI, []byte(key))
	if lmdb.IsNotFound(err) {
		return empty, nil
	}
	if err != nil {
		return 0, err
	}
	buf := bytes.NewBuffer(data)
	err = binary.Read(buf, binary.LittleEndian, &out)
	if err != nil {
		return 0, err
	}
	return out, nil
}
Exemple #3
0
func (qs *QuadStore) buildQuadWriteLMDB(tx *lmdb.Txn, q quad.Quad, id int64, isAdd bool) error {
	var entry proto.HistoryEntry
	dbi := qs.dbis[spoDB]
	data, err := tx.Get(dbi, qs.createKeyFor(spo, q))
	if err == nil {
		// We got something.
		err := entry.Unmarshal(data)
		if err != nil {
			return err
		}
	}

	if isAdd && len(entry.History)%2 == 1 {
		glog.Errorf("attempt to add existing quad %v: %#v", entry, q)
		return graph.ErrQuadExists
	}
	if !isAdd && len(entry.History)%2 == 0 {
		glog.Errorf("attempt to delete non-existent quad %v: %#v", entry, q)
		return graph.ErrQuadNotExist
	}

	entry.History = append(entry.History, uint64(id))

	bytes, err := entry.Marshal()
	if err != nil {
		glog.Errorf("Couldn't write to buffer for entry %#v: %s", entry, err)
		return err
	}
	for _, index := range [][4]quad.Direction{spo, osp, pos, cps} {
		if index == cps && q.Get(quad.Label) == "" {
			continue
		}
		dbi = qs.dbis[dbFor(index)]
		err = tx.Put(dbi, qs.createKeyFor(index, q), bytes, 0)
		if err != nil {
			return err
		}
	}
	return nil
}