Fix load index with empty file list (#26236)

Signed-off-by: Nyah01 <yah2er0ne@outlook.com>

internal/querycoordv2/checkers/index_checker.go

@@ -102,7 +102,9 @@ func (c *IndexChecker) checkReplica(ctx context.Context, collection *meta.Collec
 			continue
 		}
 		for _, info := range infos {
-			if missingFields.Contain(info.GetFieldID()) && info.GetEnableIndex() {
+			if missingFields.Contain(info.GetFieldID()) &&
+				info.GetEnableIndex() &&
+				len(info.GetIndexFilePaths()) > 0 {
 				segmentsToUpdate.Insert(segment)
 			}
 		}

internal/querycoordv2/checkers/index_checker_test.go

@@ -97,9 +97,10 @@ func (suite *IndexCheckerSuite) TestLoadIndex() {
 	suite.broker.EXPECT().GetIndexInfo(mock.Anything, int64(1), int64(2)).
 		Return([]*querypb.FieldIndexInfo{
 			{
-				FieldID:     101,
-				IndexID:     1000,
-				EnableIndex: true,
+				FieldID:        101,
+				IndexID:        1000,
+				EnableIndex:    true,
+				IndexFilePaths: []string{"index"},
 			},
 		}, nil)
 

internal/querynodev2/segments/segment_loader.go

@@ -470,7 +470,7 @@ func (loader *segmentLoader) loadSegment(ctx context.Context,
 	if segment.Type() == SegmentTypeSealed {
 		fieldID2IndexInfo := make(map[int64]*querypb.FieldIndexInfo)
 		for _, indexInfo := range loadInfo.IndexInfos {
-			if len(indexInfo.IndexFilePaths) > 0 {
+			if len(indexInfo.GetIndexFilePaths()) > 0 {
 				fieldID := indexInfo.FieldID
 				fieldID2IndexInfo[fieldID] = indexInfo
 			}
@@ -947,6 +947,11 @@ func (loader *segmentLoader) LoadIndex(ctx context.Context, segment *LocalSegmen
 			func(info *datapb.FieldBinlog) (int64, *datapb.FieldBinlog) { return info.GetFieldID(), info })
 
 		for _, info := range loadInfo.GetIndexInfos() {
+			if len(info.GetIndexFilePaths()) == 0 {
+				log.Warn("failed to add index for segment, index file list is empty, the segment may be too small")
+				return merr.WrapErrIndexNotFound("index file list empty")
+			}
+
 			fieldInfo, ok := fieldInfos[info.GetFieldID()]
 			if !ok {
 				return merr.WrapErrParameterInvalid("index info with corresponding  field info", "missing field info", strconv.FormatInt(fieldInfo.GetFieldID(), 10))

internal/querynodev2/segments/segment_loader_test.go

@@ -28,6 +28,7 @@ import (
 	"github.com/milvus-io/milvus/internal/storage"
 	"github.com/milvus-io/milvus/internal/util/initcore"
 	"github.com/milvus-io/milvus/pkg/util/funcutil"
+	"github.com/milvus-io/milvus/pkg/util/merr"
 	"github.com/milvus-io/milvus/pkg/util/metric"
 	"github.com/milvus-io/milvus/pkg/util/paramtable"
 )
@@ -352,6 +353,25 @@ func (suite *SegmentLoaderSuite) TestLoadDeltaLogs() {
 	}
 }
 
+func (suite *SegmentLoaderSuite) TestLoadIndex() {
+	ctx := context.Background()
+	segment := &LocalSegment{}
+	loadInfo := &querypb.SegmentLoadInfo{
+		SegmentID:    1,
+		PartitionID:  suite.partitionID,
+		CollectionID: suite.collectionID,
+		IndexInfos: []*querypb.FieldIndexInfo{
+			{
+				IndexFilePaths: []string{},
+			},
+		},
+	}
+
+	err := suite.loader.LoadIndex(ctx, segment, loadInfo)
+	suite.ErrorIs(err, merr.ErrIndexNotFound)
+
+}
+
 func (suite *SegmentLoaderSuite) TestLoadWithMmap() {
 	key := paramtable.Get().QueryNodeCfg.MmapDirPath.Key
 	paramtable.Get().Save(key, "/tmp/mmap-test")