feat(s3): create placeholder file for mkdir

drivers/s3/driver.go

@@ -1,6 +1,7 @@
 package s3
 
 import (
+	"bytes"
 	"fmt"
 	"github.com/Xhofe/alist/conf"
 	"github.com/Xhofe/alist/drivers/base"
@@ -9,6 +10,7 @@ import (
 	"github.com/aws/aws-sdk-go/service/s3"
 	"github.com/aws/aws-sdk-go/service/s3/s3manager"
 	log "github.com/sirupsen/logrus"
+	"io/ioutil"
 	"net/url"
 	"path/filepath"
 	"time"
@@ -78,6 +80,7 @@ func (driver S3) Items() []base.Item {
 			Label:       "placeholder filename",
 			Type:        base.TypeString,
 			Description: "default empty string",
+			Default:     defaultPlaceholderName,
 		},
 		{
 			Name:  "bool_1",
@@ -213,8 +216,19 @@ func (driver S3) Preview(path string, account *model.Account) (interface{}, erro
 }
 
 func (driver S3) MakeDir(path string, account *model.Account) error {
-	// not support, default as success
-	return nil
+	// not support, generate a placeholder file
+	_, err := driver.File(path, account)
+	// exist
+	if err != base.ErrPathNotFound {
+		return nil
+	}
+	return driver.Upload(&model.FileStream{
+		File:       ioutil.NopCloser(bytes.NewReader([]byte{})),
+		Size:       0,
+		ParentPath: path,
+		Name:       getPlaceholderName(account.Zone),
+		MIMEType:   "application/octet-stream",
+	}, account)
 }
 
 func (driver S3) Move(src string, dst string, account *model.Account) error {
@@ -277,6 +291,7 @@ func (driver S3) Upload(file *model.FileStream, account *model.Account) error {
 	}
 	uploader := s3manager.NewUploader(s)
 	key := driver.GetKey(utils.Join(file.ParentPath, file.GetFileName()), account, false)
+	log.Debugln("key:", key)
 	input := &s3manager.UploadInput{
 		Bucket: &account.Bucket,
 		Key:    &key,