frostfs-node/pkg/local_object_storage/engine/get.go
Elizaveta Chichindaeva cc7a723d77 [#1320] English Check
Signed-off-by: Elizaveta Chichindaeva <elizaveta@nspcc.ru>
2022-05-11 10:40:02 +03:00

160 lines
3.8 KiB
Go

package engine
import (
"errors"
"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/shard"
"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/util"
apistatus "github.com/nspcc-dev/neofs-sdk-go/client/status"
objectSDK "github.com/nspcc-dev/neofs-sdk-go/object"
addressSDK "github.com/nspcc-dev/neofs-sdk-go/object/address"
"go.uber.org/zap"
)
// GetPrm groups the parameters of Get operation.
type GetPrm struct {
addr *addressSDK.Address
}
// GetRes groups the resulting values of Get operation.
type GetRes struct {
obj *objectSDK.Object
}
// WithAddress is a Get option to set the address of the requested object.
//
// Option is required.
func (p *GetPrm) WithAddress(addr *addressSDK.Address) *GetPrm {
if p != nil {
p.addr = addr
}
return p
}
// Object returns the requested object.
func (r *GetRes) Object() *objectSDK.Object {
return r.obj
}
// Get reads an object from local storage.
//
// 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 local storage.
// Returns an error of type apistatus.ObjectAlreadyRemoved if the object has been marked as removed.
//
// Returns an error if executions are blocked (see BlockExecution).
func (e *StorageEngine) Get(prm *GetPrm) (res *GetRes, err error) {
err = e.execIfNotBlocked(func() error {
res, err = e.get(prm)
return err
})
return
}
func (e *StorageEngine) get(prm *GetPrm) (*GetRes, error) {
if e.metrics != nil {
defer elapsed(e.metrics.AddGetDuration)()
}
var (
obj *objectSDK.Object
siErr *objectSDK.SplitInfoError
errNotFound apistatus.ObjectNotFound
outSI *objectSDK.SplitInfo
outError error = errNotFound
shardWithMeta hashedShard
metaError error
)
shPrm := new(shard.GetPrm).
WithAddress(prm.addr)
e.iterateOverSortedShards(prm.addr, func(_ int, sh hashedShard) (stop bool) {
res, err := sh.Get(shPrm)
if err != nil {
if res.HasMeta() {
shardWithMeta = sh
metaError = err
}
switch {
case shard.IsErrNotFound(err):
return false // ignore, go to next shard
case errors.As(err, &siErr):
siErr = err.(*objectSDK.SplitInfoError)
if outSI == nil {
outSI = objectSDK.NewSplitInfo()
}
util.MergeSplitInfo(siErr.SplitInfo(), outSI)
// stop iterating over shards if SplitInfo structure is complete
if outSI.Link() != nil && outSI.LastPart() != nil {
return true
}
return false
case shard.IsErrRemoved(err):
outError = err
return true // stop, return it back
default:
e.reportShardError(sh, "could not get object from shard", err)
return false
}
}
obj = res.Object()
return true
})
if outSI != nil {
return nil, objectSDK.NewSplitInfoError(outSI)
}
if obj == nil {
if shardWithMeta.Shard == nil || !shard.IsErrNotFound(outError) {
return nil, outError
}
// If the object is not found but is present in metabase,
// try to fetch it from blobstor directly. If it is found in any
// blobstor, increase the error counter for the shard which contains the meta.
shPrm = shPrm.WithIgnoreMeta(true)
e.iterateOverSortedShards(prm.addr, func(_ int, sh hashedShard) (stop bool) {
res, err := sh.Get(shPrm)
obj = res.Object()
return err == nil
})
if obj == nil {
return nil, outError
}
e.reportShardError(shardWithMeta, "meta info was present, but object is missing",
metaError, zap.Stringer("address", prm.addr))
}
return &GetRes{
obj: obj,
}, nil
}
// Get reads object from local storage by provided address.
func Get(storage *StorageEngine, addr *addressSDK.Address) (*objectSDK.Object, error) {
res, err := storage.Get(new(GetPrm).
WithAddress(addr),
)
if err != nil {
return nil, err
}
return res.Object(), nil
}