fix(sftp): read target obj of symlink file (close #4713)

drivers/sftp/driver.go

@@ -11,6 +11,7 @@ import (
 	"github.com/alist-org/alist/v3/internal/model"
 	"github.com/alist-org/alist/v3/pkg/utils"
 	"github.com/pkg/sftp"
+	log "github.com/sirupsen/logrus"
 )
 
 type SFTP struct {
@@ -39,13 +40,15 @@ func (d *SFTP) Drop(ctx context.Context) error {
 }
 
 func (d *SFTP) List(ctx context.Context, dir model.Obj, args model.ListArgs) ([]model.Obj, error) {
+	log.Debugf("[sftp] list dir: %s", dir.GetPath())
 	files, err := d.client.ReadDir(dir.GetPath())
 	if err != nil {
 		return nil, err
 	}
-	return utils.SliceConvert(files, func(src os.FileInfo) (model.Obj, error) {
-		return fileToObj(src), nil
+	objs, err := utils.SliceConvert(files, func(src os.FileInfo) (model.Obj, error) {
+		return d.fileToObj(src, dir.GetPath())
 	})
+	return objs, err
 }
 
 func (d *SFTP) Link(ctx context.Context, file model.Obj, args model.LinkArgs) (*model.Link, error) {

drivers/sftp/types.go

@@ -2,15 +2,44 @@ package sftp
 
 import (
 	"os"
+	stdpath "path"
+	"strings"
 
 	"github.com/alist-org/alist/v3/internal/model"
+	log "github.com/sirupsen/logrus"
 )
 
-func fileToObj(f os.FileInfo) model.Obj {
-	return &model.Object{
-		Name:     f.Name(),
-		Size:     f.Size(),
-		Modified: f.ModTime(),
-		IsFolder: f.IsDir(),
+func (d *SFTP) fileToObj(f os.FileInfo, dir string) (model.Obj, error) {
+	symlink := f.Mode()&os.ModeSymlink != 0
+	if !symlink {
+		return &model.Object{
+			Name:     f.Name(),
+			Size:     f.Size(),
+			Modified: f.ModTime(),
+			IsFolder: f.IsDir(),
+		}, nil
 	}
+	path := stdpath.Join(dir, f.Name())
+	// set target path
+	target, err := d.client.ReadLink(path)
+	if err != nil {
+		return nil, err
+	}
+	if !strings.HasPrefix(target, "/") {
+		target = stdpath.Join(dir, target)
+	}
+	_f, err := d.client.Stat(target)
+	if err != nil {
+		return nil, err
+	}
+	// set basic info
+	obj := &model.Object{
+		Name:     f.Name(),
+		Size:     _f.Size(),
+		Modified: _f.ModTime(),
+		IsFolder: _f.IsDir(),
+		Path:     target,
+	}
+	log.Debugf("[sftp] obj: %+v, is symlink: %v", obj, symlink)
+	return obj, nil
 }