add DirLister interface

Signed-off-by: Nicola Murino <nicola.murino@gmail.com>

internal/webdavd/file.go

@@ -108,22 +108,24 @@ func (fi *webDavFileInfo) ContentType(_ context.Context) (string, error) {
 
 // Readdir reads directory entries from the handle
 func (f *webDavFile) Readdir(_ int) ([]os.FileInfo, error) {
+	return nil, webdav.ErrNotImplemented
+}
+
+// ReadDir implements the FileDirLister interface
+func (f *webDavFile) ReadDir() (webdav.DirLister, error) {
 	if !f.Connection.User.HasPerm(dataprovider.PermListItems, f.GetVirtualPath()) {
 		return nil, f.Connection.GetPermissionDeniedError()
 	}
-	entries, err := f.Connection.ListDir(f.GetVirtualPath())
+	lister, err := f.Connection.ListDir(f.GetVirtualPath())
 	if err != nil {
 		return nil, err
 	}
-	for idx, info := range entries {
-		entries[idx] = &webDavFileInfo{
-			FileInfo:    info,
-			Fs:          f.Fs,
-			virtualPath: path.Join(f.GetVirtualPath(), info.Name()),
-			fsPath:      f.Fs.Join(f.GetFsPath(), info.Name()),
-		}
-	}
-	return entries, nil
+	return &webDavDirLister{
+		DirLister:      lister,
+		fs:             f.Fs,
+		virtualDirPath: f.GetVirtualPath(),
+		fsDirPath:      f.GetFsPath(),
+	}, nil
 }
 
 // Stat the handle
@@ -474,3 +476,24 @@ func (f *webDavFile) Patch(patches []webdav.Proppatch) ([]webdav.Propstat, error
 	}
 	return resp, nil
 }
+
+type webDavDirLister struct {
+	vfs.DirLister
+	fs             vfs.Fs
+	virtualDirPath string
+	fsDirPath      string
+}
+
+func (l *webDavDirLister) Next(limit int) ([]os.FileInfo, error) {
+	files, err := l.DirLister.Next(limit)
+	for idx := range files {
+		info := files[idx]
+		files[idx] = &webDavFileInfo{
+			FileInfo:    info,
+			Fs:          l.fs,
+			virtualPath: path.Join(l.virtualDirPath, info.Name()),
+			fsPath:      l.fs.Join(l.fsDirPath, info.Name()),
+		}
+	}
+	return files, err
+}