[#149] metabase: Do not write virtual objects to the primary index

In the previous implementation of the metabase, it was necessary to write
virtual objects to the primary index to be able to select them. In this
approach, virtual objects can be obtained directly using Head operation.
This has a side effect in handling object operations that do not expect to
receive a virtual object header in a single operation. With recent changes,
it is no longer necessary to have records of virtual objects in the primary
index, so this no longer happens for system integrity.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

pkg/local_object_storage/metabase/db_test.go

@@ -13,6 +13,7 @@ import (
 	v2object "github.com/nspcc-dev/neofs-api-go/v2/object"
 	"github.com/nspcc-dev/neofs-node/pkg/core/object"
 	"github.com/nspcc-dev/neofs-node/pkg/util/test"
+	"github.com/pkg/errors"
 	"github.com/stretchr/testify/require"
 	"go.etcd.io/bbolt"
 )
@@ -260,3 +261,45 @@ func TestSelectNonExistentAttributes(t *testing.T) {
 	require.NoError(t, err)
 	require.Empty(t, res)
 }
+
+func TestVirtualObject(t *testing.T) {
+	db := newDB(t)
+	defer releaseDB(db)
+
+	// create object with parent
+	obj := generateObject(t, testPrm{
+		withParent: true,
+	})
+
+	require.NoError(t, db.Put(obj))
+
+	childAddr := obj.Address()
+	parAddr := obj.GetParent().Address()
+
+	// child object must be readable
+	_, err := db.Get(childAddr)
+	require.NoError(t, err)
+
+	// parent object must not be readable
+	_, err = db.Get(parAddr)
+	require.True(t, errors.Is(err, errNotFound))
+
+	fs := objectSDK.SearchFilters{}
+
+	// both objects should appear in selection
+	testSelect(t, db, fs, childAddr, parAddr)
+
+	// filter leaves
+	fs.AddLeafFilter()
+
+	// only child object should appear
+	testSelect(t, db, fs, childAddr)
+
+	fs = fs[:0]
+
+	// filter non-leaf objects
+	fs.AddNonLeafFilter()
+
+	// only parent object should appear
+	testSelect(t, db, fs, parAddr)
+}

pkg/local_object_storage/metabase/put.go

@@ -41,10 +41,12 @@ func (db *DB) Put(obj *object.Object) error {
 
 			addrKey := addressKey(obj.Address())
 
+			if !par {
 				// put header to primary bucket
 				if err := primaryBucket.Put(addrKey, data); err != nil {
 					return errors.Wrapf(err, "(%T) could not put item to primary bucket", db)
 				}
+			}
 
 			// create bucket for indices
 			indexBucket, err := tx.CreateBucketIfNotExists(indexBucket)

pkg/local_object_storage/metabase/select.go

@@ -7,42 +7,25 @@ import (
 )
 
 // Select returns list of addresses of objects that match search filters.
-func (db *DB) Select(fs object.SearchFilters) ([]*object.Address, error) {
-	res := make([]*object.Address, 0)
+func (db *DB) Select(fs object.SearchFilters) (res []*object.Address, err error) {
+	err = db.boltDB.View(func(tx *bbolt.Tx) error {
+		res, err = db.selectObjects(tx, fs)
+		return err
+	})
+
+	return
+}
+
+func (db *DB) selectObjects(tx *bbolt.Tx, fs object.SearchFilters) ([]*object.Address, error) {
+	if len(fs) == 0 {
+		return db.selectAll(tx)
+	}
 
-	err := db.boltDB.View(func(tx *bbolt.Tx) error {
 	// get indexed bucket
 	indexBucket := tx.Bucket(indexBucket)
 	if indexBucket == nil {
 		// empty storage
-			return nil
-		}
-
-		if len(fs) == 0 {
-			// get primary bucket
-			primaryBucket := tx.Bucket(primaryBucket)
-			if primaryBucket == nil {
-				// empty storage
-				return nil
-			}
-
-			// iterate over all stored addresses
-			return primaryBucket.ForEach(func(k, v []byte) error {
-				// check if object marked as deleted
-				if objectRemoved(tx, k) {
-					return nil
-				}
-
-				addr := object.NewAddress()
-				if err := addr.Parse(string(k)); err != nil {
-					// TODO: storage was broken, so we need to handle it
-					return err
-				}
-
-				res = append(res, addr)
-
-				return nil
-			})
+		return nil, nil
 	}
 
 	// keep processed addresses
@@ -52,7 +35,7 @@ func (db *DB) Select(fs object.SearchFilters) ([]*object.Address, error) {
 	for fNum := range fs {
 		matchFunc, ok := db.matchers[fs[fNum].Operation()]
 		if !ok {
-				return errors.Errorf("no function for matcher %v", fs[fNum].Operation())
+			return nil, errors.Errorf("no function for matcher %v", fs[fNum].Operation())
 		}
 
 		key := fs[fNum].Header()
@@ -61,7 +44,7 @@ func (db *DB) Select(fs object.SearchFilters) ([]*object.Address, error) {
 		keyBucket := indexBucket.Bucket([]byte(key))
 		if keyBucket == nil {
 			// no object has this attribute => empty result
-				return nil
+			return nil, nil
 		}
 
 		fVal := fs[fNum].Value()
@@ -86,11 +69,12 @@ func (db *DB) Select(fs object.SearchFilters) ([]*object.Address, error) {
 
 			return nil
 		}); err != nil {
-				return errors.Wrapf(err, "(%T) could not iterate bucket %s", db, key)
+			return nil, errors.Wrapf(err, "(%T) could not iterate bucket %s", db, key)
 		}
 	}
 
 	fLen := len(fs)
+	res := make([]*object.Address, 0, len(mAddr))
 
 	for a, ind := range mAddr {
 		if ind != fLen {
@@ -105,14 +89,35 @@ func (db *DB) Select(fs object.SearchFilters) ([]*object.Address, error) {
 		addr := object.NewAddress()
 		if err := addr.Parse(a); err != nil {
 			// TODO: storage was broken, so we need to handle it
-				return err
+			return nil, err
 		}
 
 		res = append(res, addr)
 	}
 
-		return nil
-	})
-
-	return res, err
+	return res, nil
+}
+
+func (db *DB) selectAll(tx *bbolt.Tx) ([]*object.Address, error) {
+	fs := object.SearchFilters{}
+
+	// to select all objects we can select by any property
+	// that splits objects into disjoint subsets
+	fs.AddRootFilter()
+
+	list1, err := db.selectObjects(tx, fs)
+	if err != nil {
+		return nil, errors.Wrapf(err, "(%T) could not select root objects", db)
+	}
+
+	fs = fs[:0]
+
+	fs.AddNonRootFilter()
+
+	list2, err := db.selectObjects(tx, fs)
+	if err != nil {
+		return nil, errors.Wrapf(err, "(%T) could not select non-root objects", db)
+	}
+
+	return append(list1, list2...), nil
 }