fix: distinguish not found vs deleted object

Signed-off-by: Jeronimo <jeronimo.irazabal@gmail.com>

adapters/repos/db/lsmkv/bucket.go

@@ -338,6 +338,47 @@ func (b *Bucket) Get(key []byte) ([]byte, error) {
 	return b.disk.get(key)
 }
 
+func (b *Bucket) GetErrNotFound(key []byte) ([]byte, error) {
+	b.flushLock.RLock()
+	defer b.flushLock.RUnlock()
+
+	v, err := b.active.get(key)
+	if err == nil {
+		// item found and no error, return and stop searching, since the strategy
+		// is replace
+		return v, nil
+	}
+	if errors.Is(err, lsmkv.Deleted) {
+		// deleted in the mem-table (which is always the latest) means we don't
+		// have to check the disk segments, return nil now
+		return nil, err
+	}
+
+	if err != lsmkv.NotFound {
+		panic(fmt.Sprintf("unsupported error in bucket.Get: %v\n", err))
+	}
+
+	if b.flushing != nil {
+		v, err := b.flushing.get(key)
+		if err == nil {
+			// item found and no error, return and stop searching, since the strategy
+			// is replace
+			return v, nil
+		}
+		if errors.Is(err, lsmkv.Deleted) {
+			// deleted in the now most recent memtable  means we don't have to check
+			// the disk segments, return nil now
+			return nil, err
+		}
+
+		if err != lsmkv.NotFound {
+			panic("unsupported error in bucket.Get")
+		}
+	}
+
+	return b.disk.getErrNotFound(key)
+}
+
 // GetBySecondary retrieves an object using one of its secondary keys. A bucket
 // can have an infinite number of secondary keys. Specify the secondary key
 // position as the first argument.

adapters/repos/db/lsmkv/segment_group.go

@@ -228,6 +228,38 @@ func (sg *SegmentGroup) getWithUpperSegmentBoundary(key []byte, topMostSegment i
 	return nil, nil
 }
 
+func (sg *SegmentGroup) getErrNotFound(key []byte) ([]byte, error) {
+	sg.maintenanceLock.RLock()
+	defer sg.maintenanceLock.RUnlock()
+
+	return sg.getWithUpperSegmentBoundaryErrNotFound(key, len(sg.segments)-1)
+}
+
+func (sg *SegmentGroup) getWithUpperSegmentBoundaryErrNotFound(key []byte, topMostSegment int) ([]byte, error) {
+	// assumes "replace" strategy
+
+	// start with latest and exit as soon as something is found, thus making sure
+	// the latest takes presence
+	for i := topMostSegment; i >= 0; i-- {
+		v, err := sg.segments[i].get(key)
+		if err != nil {
+			if errors.Is(err, lsmkv.NotFound) {
+				continue
+			}
+
+			if errors.Is(err, lsmkv.Deleted) {
+				return nil, err
+			}
+
+			panic(fmt.Sprintf("unsupported error in segmentGroup.get(): %v", err))
+		}
+
+		return v, nil
+	}
+
+	return nil, nil
+}
+
 func (sg *SegmentGroup) getBySecondaryIntoMemory(pos int, key []byte, buffer []byte) ([]byte, []byte, error) {
 	sg.maintenanceLock.RLock()
 	defer sg.maintenanceLock.RUnlock()

adapters/repos/db/replication.go

@@ -20,7 +20,9 @@ import (
 	"path/filepath"
 
 	"github.com/go-openapi/strfmt"
+	"github.com/pkg/errors"
 	"github.com/weaviate/weaviate/entities/additional"
+	"github.com/weaviate/weaviate/entities/lsmkv"
 	"github.com/weaviate/weaviate/entities/multi"
 	"github.com/weaviate/weaviate/entities/schema"
 	"github.com/weaviate/weaviate/entities/storobj"
@@ -326,11 +328,8 @@ func (i *Index) overwriteObjects(ctx context.Context,
 			continue
 		}
 		// valid update
-		found, err := s.ObjectByID(ctx, data.ID, nil, additional.Properties{})
-		if err == nil && found == nil {
-			// TODO: current case for locally deleted objects
-			// explicit Deleted error may be preferred but changing ObjectByID
-			// implies a global impact
+		found, err := s.ObjectByIDErrNotFound(ctx, data.ID, nil, additional.Properties{})
+		if err != nil && errors.Is(err, lsmkv.Deleted) {
 			continue
 		}
 		var curUpdateTime int64 // 0 means object doesn't exist on this node

adapters/repos/db/shard.go

@@ -74,6 +74,7 @@ type ShardLike interface {
 	PutObject(context.Context, *storobj.Object) error
 	PutObjectBatch(context.Context, []*storobj.Object) []error
 	ObjectByID(ctx context.Context, id strfmt.UUID, props search.SelectProperties, additional additional.Properties) (*storobj.Object, error)
+	ObjectByIDErrNotFound(ctx context.Context, id strfmt.UUID, props search.SelectProperties, additional additional.Properties) (*storobj.Object, error)
 	Exists(ctx context.Context, id strfmt.UUID) (bool, error)
 	ObjectSearch(ctx context.Context, limit int, filters *filters.LocalFilter, keywordRanking *searchparams.KeywordRanking, sort []filters.Sort, cursor *filters.Cursor, additional additional.Properties) ([]*storobj.Object, []float32, error)
 	ObjectVectorSearch(ctx context.Context, searchVector []float32, targetDist float32, limit int, filters *filters.LocalFilter, sort []filters.Sort, groupBy *searchparams.GroupBy, additional additional.Properties) ([]*storobj.Object, []float32, error)

adapters/repos/db/shard_lazyloader.go

@@ -190,6 +190,13 @@ func (l *LazyLoadShard) ObjectByID(ctx context.Context, id strfmt.UUID, props se
 	return l.shard.ObjectByID(ctx, id, props, additional)
 }
 
+func (l *LazyLoadShard) ObjectByIDErrNotFound(ctx context.Context, id strfmt.UUID, props search.SelectProperties, additional additional.Properties) (*storobj.Object, error) {
+	if err := l.Load(ctx); err != nil {
+		return nil, err
+	}
+	return l.shard.ObjectByIDErrNotFound(ctx, id, props, additional)
+}
+
 func (l *LazyLoadShard) Exists(ctx context.Context, id strfmt.UUID) (bool, error) {
 	if err := l.Load(ctx); err != nil {
 		return false, err

adapters/repos/db/shard_read.go

@@ -34,6 +34,29 @@ import (
 	"github.com/weaviate/weaviate/entities/storobj"
 )
 
+func (s *Shard) ObjectByIDErrNotFound(ctx context.Context, id strfmt.UUID, props search.SelectProperties, additional additional.Properties) (*storobj.Object, error) {
+	idBytes, err := uuid.MustParse(id.String()).MarshalBinary()
+	if err != nil {
+		return nil, err
+	}
+
+	bytes, err := s.store.Bucket(helpers.ObjectsBucketLSM).GetErrNotFound(idBytes)
+	if err != nil {
+		return nil, err
+	}
+
+	if bytes == nil {
+		return nil, nil
+	}
+
+	obj, err := storobj.FromBinary(bytes)
+	if err != nil {
+		return nil, errors.Wrap(err, "unmarshal object")
+	}
+
+	return obj, nil
+}
+
 func (s *Shard) ObjectByID(ctx context.Context, id strfmt.UUID, props search.SelectProperties, additional additional.Properties) (*storobj.Object, error) {
 	idBytes, err := uuid.MustParse(id.String()).MarshalBinary()
 	if err != nil {