frostfs-node/pkg/local_object_storage/blobstor/exists.go
Evgenii Stratonikov 266458fe5c [#1523] blobstor: Unify fstree and blobovnicza interfaces
Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>
2022-08-22 13:14:19 +03:00

51 lines
1.6 KiB
Go

package blobstor
import (
"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor/common"
"go.uber.org/zap"
)
// Exists checks if the object is presented in BLOB storage.
//
// Returns any error encountered that did not allow
// to completely check object existence.
func (b *BlobStor) Exists(prm common.ExistsPrm) (common.ExistsRes, error) {
// check presence in shallow dir first (cheaper)
res, err := b.existsBig(prm)
// If there was an error during existence check below,
// it will be returned unless object was found in blobovnicza.
// Otherwise, it is logged and the latest error is returned.
// FSTree | Blobovnicza | Behaviour
// found | (not tried) | return true, nil
// not found | any result | return the result
// error | found | log the error, return true, nil
// error | not found | return the error
// error | error | log the first error, return the second
if !res.Exists {
var smallErr error
res, smallErr = b.existsSmall(prm)
if err != nil && (smallErr != nil || res.Exists) {
b.log.Warn("error occured during object existence checking",
zap.Stringer("address", prm.Address),
zap.String("error", err.Error()))
err = nil
}
if err == nil {
err = smallErr
}
}
return res, err
}
// checks if object is presented in shallow dir.
func (b *BlobStor) existsBig(prm common.ExistsPrm) (common.ExistsRes, error) {
return b.fsTree.Exists(prm)
}
// existsSmall checks if object is presented in blobovnicza.
func (b *BlobStor) existsSmall(prm common.ExistsPrm) (common.ExistsRes, error) {
return b.blobovniczas.Exists(prm)
}