frostfs-node/pkg/local_object_storage/shard/restore.go
Pavel Karpy 7b6363f4c6 [] shard: Do not use pointers as the results
Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>
2022-06-06 18:03:12 +03:00

133 lines
2.7 KiB
Go

package shard
import (
"bytes"
"encoding/binary"
"errors"
"io"
"os"
"github.com/nspcc-dev/neofs-sdk-go/object"
)
// ErrInvalidMagic is returned when dump format is invalid.
var ErrInvalidMagic = errors.New("invalid magic")
// RestorePrm groups the parameters of Restore operation.
type RestorePrm struct {
path string
stream io.Reader
ignoreErrors bool
}
// WithPath is a Restore option to set the destination path.
func (p *RestorePrm) WithPath(path string) {
p.path = path
}
// WithStream is a Restore option to set the stream to read objects from.
// It takes priority over `WithPath` option.
func (p *RestorePrm) WithStream(r io.Reader) {
p.stream = r
}
// WithIgnoreErrors is a Restore option which allows to ignore errors encountered during restore.
// Corrupted objects will not be processed.
func (p *RestorePrm) WithIgnoreErrors(ignore bool) {
p.ignoreErrors = ignore
}
// RestoreRes groups the result fields of Restore operation.
type RestoreRes struct {
count int
failed int
}
// Count return amount of object written.
func (r RestoreRes) Count() int {
return r.count
}
// FailCount return amount of object skipped.
func (r RestoreRes) FailCount() int {
return r.failed
}
// Restore restores objects from the dump prepared by Dump.
//
// Returns any error encountered.
func (s *Shard) Restore(prm RestorePrm) (RestoreRes, error) {
// Disallow changing mode during restore.
s.m.RLock()
defer s.m.RUnlock()
if s.info.Mode != ModeReadWrite {
return RestoreRes{}, ErrReadOnlyMode
}
r := prm.stream
if r == nil {
f, err := os.OpenFile(prm.path, os.O_RDONLY, os.ModeExclusive)
if err != nil {
return RestoreRes{}, err
}
defer f.Close()
r = f
}
var m [4]byte
_, _ = io.ReadFull(r, m[:])
if !bytes.Equal(m[:], dumpMagic) {
return RestoreRes{}, ErrInvalidMagic
}
var putPrm PutPrm
var count, failCount int
var data []byte
var size [4]byte
for {
// If there are less than 4 bytes left, `Read` returns nil error instead of
// io.ErrUnexpectedEOF, thus `ReadFull` is used.
_, err := io.ReadFull(r, size[:])
if err != nil {
if errors.Is(err, io.EOF) {
break
}
return RestoreRes{}, err
}
sz := binary.LittleEndian.Uint32(size[:])
if uint32(cap(data)) < sz {
data = make([]byte, sz)
} else {
data = data[:sz]
}
_, err = r.Read(data)
if err != nil {
return RestoreRes{}, err
}
obj := object.New()
err = obj.Unmarshal(data)
if err != nil {
if prm.ignoreErrors {
failCount++
continue
}
return RestoreRes{}, err
}
putPrm.WithObject(obj)
_, err = s.Put(putPrm)
if err != nil {
return RestoreRes{}, err
}
count++
}
return RestoreRes{count: count, failed: failCount}, nil
}