fix(indexer): crash on directory traversal

internal/indexer/indexer.go

@@ -68,6 +68,10 @@ func buildImageSets(folder string, ascending bool, option config.ExtractOption)
 	mutext := &sync.Mutex{}
 
 	_ = filepath.WalkDir(folder, func(path string, info os.DirEntry, err error) error {
+		if err != nil {
+			log.Warn().Msgf("Failed to extract info from %s (%v)", path, err)
+			return nil
+		}
 		if info.IsDir() || !images.IsPhotoSupported(path) {
 			return nil
 		}

internal/indexer/indexer_test.go

@@ -2,6 +2,7 @@ package indexer
 
 import (
 	"html/template"
+	"os"
 	"path/filepath"
 	"testing"
 
@@ -88,6 +89,13 @@ func TestBuildImageSets(t *testing.T) {
 	})
 }
 
+func TestInvalidBuildImageSets(t *testing.T) {
+	tmp, _ := os.MkdirTemp("", "foto-test")
+	path := filepath.Join(tmp, "folder-not-exist")
+	// no crash expected
+	_ = buildImageSets(path, true, defaultOption)
+}
+
 func TestBuildImageSet(t *testing.T) {
 	set, _ := buildImageSet(testdata.Testfile, defaultOption)
 	assert.Equal(t, filepath.Base(testdata.Testfile), set.FileName)