satellite/metabase: don't create delete markers for pending

Fix a case where it was possible to create a delete marker when only
pending object was present.

The solution is not pretty, but we have a TODO note to cleanup the
precommit code, so let's fix the bug first.

Change-Id: I0ab66d745443c9dccbf29ef32389dd912b2d9caf

satellite/metabase/delete.go

@@ -364,14 +364,13 @@ func (db *DB) DeleteObjectLastCommitted(
 			return DeleteObjectResult{}, Error.Wrap(err)
 		}
 
-		var precommit precommitConstraintResult
+		var precommit precommitConstraintWithNonPendingResult
 		err = txutil.WithTx(ctx, db.db, nil, func(ctx context.Context, tx tagsql.Tx) (err error) {
-			precommit, err = db.precommitDeleteUnversioned(ctx, opts.ObjectLocation, tx)
+			precommit, err = db.precommitDeleteUnversionedWithNonPending(ctx, opts.ObjectLocation, tx)
 			if err != nil {
 				return Error.Wrap(err)
 			}
-			// TODO(ver): currently it allows adding delete markers when pending objects are present.
+			if precommit.HighestVersion == 0 || precommit.HighestNonPendingVersion == 0 {
-			if precommit.HighestVersion == 0 {
 				// an object didn't exist in the first place
 				return ErrObjectNotFound.New("unable to delete object")
 			}

satellite/metabase/delete_test.go

@@ -704,6 +704,38 @@ func TestDeleteObjectVersioning(t *testing.T) {
 				},
 			}.Check(ctx, t, db)
 		})
+
+		t.Run("delete last pending with suspended", func(t *testing.T) {
+			defer metabasetest.DeleteAll{}.Check(ctx, t, db)
+
+			obj := metabasetest.RandObjectStream()
+			pending := metabasetest.BeginObjectExactVersion{
+				Opts: metabase.BeginObjectExactVersion{
+					ObjectStream: obj,
+					Encryption:   metabasetest.DefaultEncryption,
+				},
+			}.Check(ctx, t, db)
+
+			metabasetest.DeleteObjectLastCommitted{
+				Opts: metabase.DeleteObjectLastCommitted{
+					ObjectLocation: metabase.ObjectLocation{
+						ProjectID:  obj.ProjectID,
+						BucketName: obj.BucketName,
+						ObjectKey:  obj.ObjectKey,
+					},
+					Versioned: false,
+					Suspended: true,
+				},
+				ErrClass: &metabase.ErrObjectNotFound,
+				ErrText:  "unable to delete object",
+			}.Check(ctx, t, db)
+
+			metabasetest.Verify{
+				Objects: []metabase.RawObject{
+					metabase.RawObject(pending),
+				},
+			}.Check(ctx, t, db)
+		})
 	})
 }
 

satellite/metabase/precommit.go

@@ -238,3 +238,147 @@ func (db *DB) precommitDeleteUnversioned(ctx context.Context, loc ObjectLocation
 
 	return result, nil
 }
+
+type precommitConstraintWithNonPendingResult struct {
+	Deleted []Object
+
+	// DeletedObjectCount returns how many objects were deleted.
+	DeletedObjectCount int
+	// DeletedSegmentCount returns how many segments were deleted.
+	DeletedSegmentCount int
+
+	// HighestVersion returns tha highest version that was present in the table.
+	// It returns 0 if there was none.
+	HighestVersion Version
+
+	// HighestNonPendingVersion returns tha highest non-pending version that was present in the table.
+	// It returns 0 if there was none.
+	HighestNonPendingVersion Version
+}
+
+func (r *precommitConstraintWithNonPendingResult) submitMetrics() {
+	mon.Meter("object_delete").Mark(r.DeletedObjectCount)
+	mon.Meter("segment_delete").Mark(r.DeletedSegmentCount)
+}
+
+// precommitDeleteUnversionedWithNonPending deletes the unversioned object at loc and also returns the highest version and highest committed version.
+func (db *DB) precommitDeleteUnversionedWithNonPending(ctx context.Context, loc ObjectLocation, tx stmtRow) (result precommitConstraintWithNonPendingResult, err error) {
+	defer mon.Task()(&ctx)(&err)
+
+	if err := loc.Verify(); err != nil {
+		return precommitConstraintWithNonPendingResult{}, Error.Wrap(err)
+	}
+
+	var deleted Object
+
+	// TODO(ver): this scanning can probably simplified somehow.
+
+	var version sql.NullInt64
+	var streamID uuid.NullUUID
+	var createdAt sql.NullTime
+	var segmentCount, fixedSegmentSize sql.NullInt32
+	var totalPlainSize, totalEncryptedSize sql.NullInt64
+	var status sql.NullByte
+	var encryptionParams nullableValue[encryptionParameters]
+	encryptionParams.value.EncryptionParameters = &deleted.Encryption
+
+	err = tx.QueryRowContext(ctx, `
+		WITH highest_object AS (
+			SELECT MAX(version) as version
+			FROM objects
+			WHERE (project_id, bucket_name, object_key) = ($1, $2, $3)
+		), highest_non_pending_object AS (
+			SELECT MAX(version) as version
+			FROM objects
+			WHERE (project_id, bucket_name, object_key) = ($1, $2, $3)
+				AND status <> `+statusPending+`
+		), deleted_objects AS (
+			DELETE FROM objects
+			WHERE
+				(project_id, bucket_name, object_key) = ($1, $2, $3)
+				AND status IN `+statusesUnversioned+`
+			RETURNING
+				version, stream_id,
+				created_at, expires_at,
+				status, segment_count,
+				encrypted_metadata_nonce, encrypted_metadata, encrypted_metadata_encrypted_key,
+				total_plain_size, total_encrypted_size, fixed_segment_size,
+				encryption
+		), deleted_segments AS (
+			DELETE FROM segments
+			WHERE segments.stream_id IN (SELECT deleted_objects.stream_id FROM deleted_objects)
+			RETURNING segments.stream_id
+		)
+		SELECT
+			(SELECT version FROM deleted_objects),
+			(SELECT stream_id FROM deleted_objects),
+			(SELECT created_at FROM deleted_objects),
+			(SELECT expires_at FROM deleted_objects),
+			(SELECT status FROM deleted_objects),
+			(SELECT segment_count FROM deleted_objects),
+			(SELECT encrypted_metadata_nonce FROM deleted_objects),
+			(SELECT encrypted_metadata FROM deleted_objects),
+			(SELECT encrypted_metadata_encrypted_key FROM deleted_objects),
+			(SELECT total_plain_size FROM deleted_objects),
+			(SELECT total_encrypted_size FROM deleted_objects),
+			(SELECT fixed_segment_size FROM deleted_objects),
+			(SELECT encryption FROM deleted_objects),
+			(SELECT count(*) FROM deleted_objects),
+			(SELECT count(*) FROM deleted_segments),
+			coalesce((SELECT version FROM highest_object), 0),
+			coalesce((SELECT version FROM highest_non_pending_object), 0)
+	`, loc.ProjectID, []byte(loc.BucketName), loc.ObjectKey).
+		Scan(
+			&version,
+			&streamID,
+			&createdAt,
+			&deleted.ExpiresAt,
+			&status,
+			&segmentCount,
+			&deleted.EncryptedMetadataNonce,
+			&deleted.EncryptedMetadata,
+			&deleted.EncryptedMetadataEncryptedKey,
+			&totalPlainSize,
+			&totalEncryptedSize,
+			&fixedSegmentSize,
+			&encryptionParams,
+			&result.DeletedObjectCount,
+			&result.DeletedSegmentCount,
+			&result.HighestVersion,
+			&result.HighestNonPendingVersion,
+		)
+
+	if err != nil {
+		return precommitConstraintWithNonPendingResult{}, Error.Wrap(err)
+	}
+
+	deleted.ProjectID = loc.ProjectID
+	deleted.BucketName = loc.BucketName
+	deleted.ObjectKey = loc.ObjectKey
+	deleted.Version = Version(version.Int64)
+
+	deleted.Status = ObjectStatus(status.Byte)
+	deleted.StreamID = streamID.UUID
+	deleted.CreatedAt = createdAt.Time
+	deleted.SegmentCount = segmentCount.Int32
+
+	deleted.TotalPlainSize = totalPlainSize.Int64
+	deleted.TotalEncryptedSize = totalEncryptedSize.Int64
+	deleted.FixedSegmentSize = fixedSegmentSize.Int32
+
+	if result.DeletedObjectCount > 1 {
+		db.log.Error("object with multiple committed versions were found!",
+			zap.Stringer("Project ID", loc.ProjectID), zap.String("Bucket Name", loc.BucketName),
+			zap.ByteString("Object Key", []byte(loc.ObjectKey)), zap.Int("deleted", result.DeletedObjectCount))
+
+		mon.Meter("multiple_committed_versions").Mark(1)
+
+		return result, Error.New("internal error: multiple committed unversioned objects")
+	}
+
+	if result.DeletedObjectCount > 0 {
+		result.Deleted = append(result.Deleted, deleted)
+	}
+
+	return result, nil
+}