frostfs-node/pkg/local_object_storage/shard/get.go
Evgenii Stratonikov 4944490ffb [#1559] local_object_storage: Move shard to the DegradedReadOnly mode
`Degraded` mode can be set by the administrator if needed.
Modifying operations in this mode can lead node into an inconsistent state
because metabase checks such as lock checking are not performed.

Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>
2022-07-21 17:56:06 +03:00

161 lines
4.1 KiB
Go

package shard
import (
"fmt"
"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobovnicza"
"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/blobstor"
meta "github.com/nspcc-dev/neofs-node/pkg/local_object_storage/metabase"
"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/writecache"
apistatus "github.com/nspcc-dev/neofs-sdk-go/client/status"
objectSDK "github.com/nspcc-dev/neofs-sdk-go/object"
oid "github.com/nspcc-dev/neofs-sdk-go/object/id"
"go.uber.org/zap"
)
// storFetcher is a type to unify object fetching mechanism in `fetchObjectData`
// method. It represents generalization of `getSmall` and `getBig` methods.
type storFetcher = func(stor *blobstor.BlobStor, id *blobovnicza.ID) (*objectSDK.Object, error)
// GetPrm groups the parameters of Get operation.
type GetPrm struct {
addr oid.Address
skipMeta bool
}
// GetRes groups the resulting values of Get operation.
type GetRes struct {
obj *objectSDK.Object
hasMeta bool
}
// SetAddress is a Get option to set the address of the requested object.
//
// Option is required.
func (p *GetPrm) SetAddress(addr oid.Address) {
p.addr = addr
}
// SetIgnoreMeta is a Get option try to fetch object from blobstor directly,
// without accessing metabase.
func (p *GetPrm) SetIgnoreMeta(ignore bool) {
p.skipMeta = ignore
}
// Object returns the requested object.
func (r GetRes) Object() *objectSDK.Object {
return r.obj
}
// HasMeta returns true if info about the object was found in the metabase.
func (r GetRes) HasMeta() bool {
return r.hasMeta
}
// Get reads an object from shard.
//
// Returns any error encountered that
// did not allow to completely read the object part.
//
// Returns an error of type apistatus.ObjectNotFound if the requested object is missing in shard.
// Returns an error of type apistatus.ObjectAlreadyRemoved if the requested object has been marked as removed in shard.
func (s *Shard) Get(prm GetPrm) (GetRes, error) {
var big, small storFetcher
big = func(stor *blobstor.BlobStor, _ *blobovnicza.ID) (*objectSDK.Object, error) {
var getBigPrm blobstor.GetBigPrm
getBigPrm.SetAddress(prm.addr)
res, err := stor.GetBig(getBigPrm)
if err != nil {
return nil, err
}
return res.Object(), nil
}
small = func(stor *blobstor.BlobStor, id *blobovnicza.ID) (*objectSDK.Object, error) {
var getSmallPrm blobstor.GetSmallPrm
getSmallPrm.SetAddress(prm.addr)
getSmallPrm.SetBlobovniczaID(id)
res, err := stor.GetSmall(getSmallPrm)
if err != nil {
return nil, err
}
return res.Object(), nil
}
skipMeta := prm.skipMeta || s.GetMode().NoMetabase()
obj, hasMeta, err := s.fetchObjectData(prm.addr, skipMeta, big, small)
return GetRes{
obj: obj,
hasMeta: hasMeta,
}, err
}
// fetchObjectData looks through writeCache and blobStor to find object.
func (s *Shard) fetchObjectData(addr oid.Address, skipMeta bool, big, small storFetcher) (*objectSDK.Object, bool, error) {
var (
err error
res *objectSDK.Object
)
if s.hasWriteCache() {
res, err = s.writeCache.Get(addr)
if err == nil {
return res, false, nil
}
if writecache.IsErrNotFound(err) {
s.log.Debug("object is missing in write-cache")
} else {
s.log.Error("failed to fetch object from write-cache", zap.Error(err))
}
}
var exists bool
if !skipMeta {
var mPrm meta.ExistsPrm
mPrm.SetAddress(addr)
mRes, err := s.metaBase.Exists(mPrm)
if err != nil && !s.GetMode().NoMetabase() {
return res, false, err
}
exists = mRes.Exists()
}
if skipMeta || err != nil {
res, err = small(s.blobStor, nil)
if err == nil || IsErrOutOfRange(err) {
return res, false, err
}
res, err = big(s.blobStor, nil)
return res, false, err
}
if !exists {
var errNotFound apistatus.ObjectNotFound
return nil, false, errNotFound
}
var mPrm meta.IsSmallPrm
mPrm.WithAddress(addr)
mRes, err := s.metaBase.IsSmall(mPrm)
if err != nil {
return nil, true, fmt.Errorf("can't fetch blobovnicza id from metabase: %w", err)
}
if mRes.BlobovniczaID() != nil {
res, err = small(s.blobStor, mRes.BlobovniczaID())
} else {
res, err = big(s.blobStor, nil)
}
return res, true, err
}