optional header for complete upload part

object_part.go

@@ -114,8 +114,9 @@ func (s *ObjectService) ListParts(ctx context.Context, name, uploadID string, op
 
 // CompleteMultipartUploadOptions is the option of CompleteMultipartUpload
 type CompleteMultipartUploadOptions struct {
-	XMLName xml.Name `xml:"CompleteMultipartUpload"`
-	Parts   []Object `xml:"Part"`
+	XMLName       xml.Name     `xml:"CompleteMultipartUpload" header:"-" url:"-"`
+	Parts         []Object     `xml:"Part" header:"-" url:"-"`
+	XOptionHeader *http.Header `header:"-,omitempty" xml:"-" url:"-"`
 }
 
 // CompleteMultipartUploadResult is the result CompleteMultipartUpload
@@ -164,6 +165,7 @@ func (s *ObjectService) CompleteMultipartUpload(ctx context.Context, name, uploa
 		baseURL:   s.client.BaseURL.BucketURL,
 		uri:       u,
 		method:    http.MethodPost,
+		optHeader: opt,
 		body:      opt,
 		result:    &res,
 	}