frostfs-node/pkg/local_object_storage/metabase/exists.go
Evgenii Stratonikov 34501685b7 [] local_object_storage: Move ErrObjectIsExpired to another package
Signed-off-by: Evgenii Stratonikov <evgeniy@morphbits.ru>
2022-10-31 11:41:24 +03:00

189 lines
5.3 KiB
Go

package meta
import (
"fmt"
"strconv"
objectV2 "github.com/nspcc-dev/neofs-api-go/v2/object"
"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/util/logicerr"
apistatus "github.com/nspcc-dev/neofs-sdk-go/client/status"
cid "github.com/nspcc-dev/neofs-sdk-go/container/id"
objectSDK "github.com/nspcc-dev/neofs-sdk-go/object"
oid "github.com/nspcc-dev/neofs-sdk-go/object/id"
"go.etcd.io/bbolt"
)
// ExistsPrm groups the parameters of Exists operation.
type ExistsPrm struct {
addr oid.Address
}
// ExistsRes groups the resulting values of Exists operation.
type ExistsRes struct {
exists bool
}
var ErrLackSplitInfo = logicerr.New("no split info on parent object")
// SetAddress is an Exists option to set object checked for existence.
func (p *ExistsPrm) SetAddress(addr oid.Address) {
p.addr = addr
}
// Exists returns the fact that the object is in the metabase.
func (p ExistsRes) Exists() bool {
return p.exists
}
// Exists returns ErrAlreadyRemoved if addr was marked as removed. Otherwise it
// returns true if addr is in primary index or false if it is not.
//
// Returns an error of type apistatus.ObjectAlreadyRemoved if object has been placed in graveyard.
// Returns the object.ErrObjectIsExpired if the object is presented but already expired.
func (db *DB) Exists(prm ExistsPrm) (res ExistsRes, err error) {
db.modeMtx.RLock()
defer db.modeMtx.RUnlock()
currEpoch := db.epochState.CurrentEpoch()
err = db.boltDB.View(func(tx *bbolt.Tx) error {
res.exists, err = db.exists(tx, prm.addr, currEpoch)
return err
})
return
}
func (db *DB) exists(tx *bbolt.Tx, addr oid.Address, currEpoch uint64) (exists bool, err error) {
// check graveyard and object expiration first
switch objectStatus(tx, addr, currEpoch) {
case 1:
return false, logicerr.Wrap(apistatus.ObjectNotFound{})
case 2:
return false, logicerr.Wrap(apistatus.ObjectAlreadyRemoved{})
case 3:
return false, ErrObjectIsExpired
}
objKey := objectKey(addr.Object(), make([]byte, objectKeySize))
cnr := addr.Container()
key := make([]byte, bucketKeySize)
// if graveyard is empty, then check if object exists in primary bucket
if inBucket(tx, primaryBucketName(cnr, key), objKey) {
return true, nil
}
// if primary bucket is empty, then check if object exists in parent bucket
if inBucket(tx, parentBucketName(cnr, key), objKey) {
splitInfo, err := getSplitInfo(tx, cnr, objKey)
if err != nil {
return false, err
}
return false, logicerr.Wrap(objectSDK.NewSplitInfoError(splitInfo))
}
// if parent bucket is empty, then check if object exists in typed buckets
return firstIrregularObjectType(tx, cnr, objKey) != objectSDK.TypeRegular, nil
}
// objectStatus returns:
// - 0 if object is available;
// - 1 if object with GC mark;
// - 2 if object is covered with tombstone;
// - 3 if object is expired.
func objectStatus(tx *bbolt.Tx, addr oid.Address, currEpoch uint64) uint8 {
// we check only if the object is expired in the current
// epoch since it is considered the only corner case: the
// GC is expected to collect all the objects that have
// expired previously for less than the one epoch duration
var expired bool
// bucket with objects that have expiration attr
attrKey := make([]byte, bucketKeySize+len(objectV2.SysAttributeExpEpoch))
expirationBucket := tx.Bucket(attributeBucketName(addr.Container(), objectV2.SysAttributeExpEpoch, attrKey))
if expirationBucket != nil {
// bucket that contains objects that expire in the current epoch
prevEpochBkt := expirationBucket.Bucket([]byte(strconv.FormatUint(currEpoch-1, 10)))
if prevEpochBkt != nil {
rawOID := objectKey(addr.Object(), make([]byte, objectKeySize))
if prevEpochBkt.Get(rawOID) != nil {
expired = true
}
}
}
if expired {
return 3
}
graveyardBkt := tx.Bucket(graveyardBucketName)
garbageBkt := tx.Bucket(garbageBucketName)
addrKey := addressKey(addr, make([]byte, addressKeySize))
return inGraveyardWithKey(addrKey, graveyardBkt, garbageBkt)
}
func inGraveyardWithKey(addrKey []byte, graveyard, garbageBCK *bbolt.Bucket) uint8 {
if graveyard == nil {
// incorrect metabase state, does not make
// sense to check garbage bucket
return 0
}
val := graveyard.Get(addrKey)
if val == nil {
if garbageBCK == nil {
// incorrect node state
return 0
}
val = garbageBCK.Get(addrKey)
if val != nil {
// object has been marked with GC
return 1
}
// neither in the graveyard
// nor was marked with GC mark
return 0
}
// object in the graveyard
return 2
}
// inBucket checks if key <key> is present in bucket <name>.
func inBucket(tx *bbolt.Tx, name, key []byte) bool {
bkt := tx.Bucket(name)
if bkt == nil {
return false
}
// using `get` as `exists`: https://github.com/boltdb/bolt/issues/321
val := bkt.Get(key)
return len(val) != 0
}
// getSplitInfo returns SplitInfo structure from root index. Returns error
// if there is no `key` record in root index.
func getSplitInfo(tx *bbolt.Tx, cnr cid.ID, key []byte) (*objectSDK.SplitInfo, error) {
bucketName := rootBucketName(cnr, make([]byte, bucketKeySize))
rawSplitInfo := getFromBucket(tx, bucketName, key)
if len(rawSplitInfo) == 0 {
return nil, ErrLackSplitInfo
}
splitInfo := objectSDK.NewSplitInfo()
err := splitInfo.Unmarshal(rawSplitInfo)
if err != nil {
return nil, fmt.Errorf("can't unmarshal split info from root index: %w", err)
}
return splitInfo, nil
}