[#308] object/relations: List relations in split order

Signed-off-by: Denis Kirillov <denis@nspcc.ru>

object/relations/relations.go

@@ -19,8 +19,9 @@ type Tokens struct {
 }
 
 type Relations interface {
-	// GetSplitInfo tries to get split info by root object id.
+	// GetSplitInfo tries to get split info by some object id.
-	// If object isn't virtual it returns ErrNoSplitInfo.
+	// This method must return split info on any object from split chain as well as on parent/linking object.
+	// If object doesn't have any split information returns ErrNoSplitInfo.
 	GetSplitInfo(ctx context.Context, cnrID cid.ID, rootID oid.ID, tokens Tokens) (*object.SplitInfo, error)
 
 	// ListChildrenByLinker returns list of children for link object.
@@ -31,9 +32,6 @@ type Relations interface {
 	// If no previous object it returns ErrNoLeftSibling.
 	GetLeftSibling(ctx context.Context, cnrID cid.ID, objID oid.ID, tokens Tokens) (oid.ID, error)
 
-	// FindSiblingBySplitID returns all objects that relates to the provided split id.
-	FindSiblingBySplitID(ctx context.Context, cnrID cid.ID, splitID *object.SplitID, tokens Tokens) ([]oid.ID, error)
-
 	// FindSiblingByParentID returns all object that relates to the provided parent id.
 	FindSiblingByParentID(ctx context.Context, cnrID cid.ID, parentID oid.ID, tokens Tokens) ([]oid.ID, error)
 }
@@ -46,9 +44,15 @@ var (
 	ErrNoSplitInfo = errors.New("no split info")
 )
 
-// ListAllRelations return all related phy objects for provided root object ID.
+// ListAllRelations return all related phy objects for provided root object ID in split-chain order.
-// Result doesn't include root object ID itself.
+// Result doesn't include root object ID itself. If linking object is found its id will be the last one.
 func ListAllRelations(ctx context.Context, rels Relations, cnrID cid.ID, rootObjID oid.ID, tokens Tokens) ([]oid.ID, error) {
+	return ListRelations(ctx, rels, cnrID, rootObjID, tokens, true)
+}
+
+// ListRelations return all related phy objects for provided root object ID in split-chain order.
+// Result doesn't include root object ID itself.
+func ListRelations(ctx context.Context, rels Relations, cnrID cid.ID, rootObjID oid.ID, tokens Tokens, includeLinking bool) ([]oid.ID, error) {
 	splitInfo, err := rels.GetSplitInfo(ctx, cnrID, rootObjID, tokens)
 	if err != nil {
 		if errors.Is(err, ErrNoSplitInfo) {
@@ -59,22 +63,40 @@ func ListAllRelations(ctx context.Context, rels Relations, cnrID cid.ID, rootObj
 
 	// collect split chain by the descending ease of operations (ease is evaluated heuristically).
 	// If any approach fails, we don't try the next since we assume that it will fail too.
+	if _, ok := splitInfo.Link(); !ok {
+		// the list is expected to contain last part and (probably) split info
+		list, err := rels.FindSiblingByParentID(ctx, cnrID, rootObjID, tokens)
+		if err != nil {
+			return nil, fmt.Errorf("failed to find object children: %w", err)
+		}
+
+		for _, id := range list {
+			split, err := rels.GetSplitInfo(ctx, cnrID, id, tokens)
+			if err != nil {
+				if errors.Is(err, ErrNoSplitInfo) {
+					continue
+				}
+				return nil, fmt.Errorf("failed to get split info: %w", err)
+			}
+			if link, ok := split.Link(); ok {
+				splitInfo.SetLink(link)
+			}
+			if last, ok := split.LastPart(); ok {
+				splitInfo.SetLastPart(last)
+			}
+		}
+	}
+
 	if idLinking, ok := splitInfo.Link(); ok {
 		children, err := rels.ListChildrenByLinker(ctx, cnrID, idLinking, tokens)
 		if err != nil {
 			return nil, fmt.Errorf("failed to get linking object's header: %w", err)
 		}
 
-		// include linking object
+		if includeLinking {
-		return append(children, idLinking), nil
+			children = append(children, idLinking)
-	}
-
-	if idSplit := splitInfo.SplitID(); idSplit != nil {
-		members, err := rels.FindSiblingBySplitID(ctx, cnrID, idSplit, tokens)
-		if err != nil {
-			return nil, fmt.Errorf("failed to search objects by split ID: %w", err)
 		}
-		return members, nil
+		return children, nil
 	}
 
 	idMember, ok := splitInfo.LastPart()
@@ -85,9 +107,6 @@ func ListAllRelations(ctx context.Context, rels Relations, cnrID cid.ID, rootObj
 	chain := []oid.ID{idMember}
 	chainSet := map[oid.ID]struct{}{idMember: {}}
 
-	// prmHead.SetRawFlag(false)
-	// split members are almost definitely singular, but don't get hung up on it
-
 	for {
 		idMember, err = rels.GetLeftSibling(ctx, cnrID, idMember, tokens)
 		if err != nil {
@@ -101,20 +120,9 @@ func ListAllRelations(ctx context.Context, rels Relations, cnrID cid.ID, rootObj
 			return nil, fmt.Errorf("duplicated member in the split chain %s", idMember)
 		}
 
-		chain = append(chain, idMember)
+		chain = append([]oid.ID{idMember}, chain...)
 		chainSet[idMember] = struct{}{}
 	}
 
-	list, err := rels.FindSiblingByParentID(ctx, cnrID, rootObjID, tokens)
-	if err != nil {
-		return nil, fmt.Errorf("failed to find object children: %w", err)
-	}
-
-	for i := range list {
-		if _, ok = chainSet[list[i]]; !ok {
-			chain = append(chain, list[i])
-		}
-	}
-
 	return chain, nil
 }

pool/pool.go

@@ -2510,7 +2510,7 @@ func (p *Pool) GetSplitInfo(ctx context.Context, cnrID cid.ID, objID oid.ID, tok
 	}
 	prm.MarkRaw()
 
-	_, err := p.HeadObject(ctx, prm)
+	res, err := p.HeadObject(ctx, prm)
 
 	var errSplit *object.SplitInfoError
 
@@ -2518,7 +2518,21 @@ func (p *Pool) GetSplitInfo(ctx context.Context, cnrID cid.ID, objID oid.ID, tok
 	case errors.As(err, &errSplit):
 		return errSplit.SplitInfo(), nil
 	case err == nil:
-		return nil, relations.ErrNoSplitInfo
+		if res.SplitID() == nil {
+			return nil, relations.ErrNoSplitInfo
+		}
+
+		splitInfo := object.NewSplitInfo()
+		splitInfo.SetSplitID(res.SplitID())
+		if res.HasParent() {
+			if len(res.Children()) > 0 {
+				splitInfo.SetLink(objID)
+			} else {
+				splitInfo.SetLastPart(objID)
+			}
+		}
+
+		return splitInfo, nil
 	default:
 		return nil, fmt.Errorf("failed to get raw object header: %w", err)
 	}
@@ -2574,38 +2588,6 @@ func (p *Pool) GetLeftSibling(ctx context.Context, cnrID cid.ID, objID oid.ID, t
 	return idMember, nil
 }
 
-// FindSiblingBySplitID implements relations.Relations.
-func (p *Pool) FindSiblingBySplitID(ctx context.Context, cnrID cid.ID, splitID *object.SplitID, tokens relations.Tokens) ([]oid.ID, error) {
-	var query object.SearchFilters
-	query.AddSplitIDFilter(object.MatchStringEqual, splitID)
-
-	var prm PrmObjectSearch
-	prm.SetContainerID(cnrID)
-	prm.SetFilters(query)
-	if tokens.Bearer != nil {
-		prm.UseBearer(*tokens.Bearer)
-	}
-	if tokens.Session != nil {
-		prm.UseSession(*tokens.Session)
-	}
-
-	res, err := p.SearchObjects(ctx, prm)
-	if err != nil {
-		return nil, fmt.Errorf("failed to search objects by split ID: %w", err)
-	}
-
-	var members []oid.ID
-	err = res.Iterate(func(id oid.ID) bool {
-		members = append(members, id)
-		return false
-	})
-	if err != nil {
-		return nil, fmt.Errorf("failed to iterate found objects: %w", err)
-	}
-
-	return members, nil
-}
-
 // FindSiblingByParentID implements relations.Relations.
 func (p *Pool) FindSiblingByParentID(ctx context.Context, cnrID cid.ID, objID oid.ID, tokens relations.Tokens) ([]oid.ID, error) {
 	var query object.SearchFilters