package shard import ( "errors" "github.com/nspcc-dev/neofs-node/pkg/local_object_storage/shard/mode" ) // ErrReadOnlyMode is returned when it is impossible to apply operation // that changes shard's memory due to the "read-only" shard's mode. var ErrReadOnlyMode = errors.New("shard is in read-only mode") // ErrDegradedMode is returned when operation requiring metabase is executed in degraded mode. var ErrDegradedMode = errors.New("shard is in degraded mode") // SetMode sets mode of the shard. // // Returns any error encountered that did not allow // setting shard mode. func (s *Shard) SetMode(m mode.Mode) error { s.m.Lock() defer s.m.Unlock() return s.setMode(m) } func (s *Shard) setMode(m mode.Mode) error { components := []interface{ SetMode(mode.Mode) error }{ s.metaBase, s.blobStor, } if s.hasWriteCache() { components = append(components, s.writeCache) } if s.pilorama != nil { components = append(components, s.pilorama) } // The usual flow of the requests (pilorama is independent): // writecache -> blobstor -> metabase // For mode.ReadOnly and mode.Degraded the order is: // writecache -> blobstor -> metabase // For mode.ReadWrite it is the opposite: // metabase -> blobstor -> writecache if m != mode.ReadWrite { if s.hasWriteCache() { components[0], components[2] = components[2], components[0] } else { components[0], components[1] = components[1], components[0] } } for i := range components { if err := components[i].SetMode(m); err != nil { return err } } s.info.Mode = m return nil } // GetMode returns mode of the shard. func (s *Shard) GetMode() mode.Mode { s.m.RLock() defer s.m.RUnlock() return s.info.Mode }