From 561a2ff0bcdb72f320b1d3a81da63dd6beb41548 Mon Sep 17 00:00:00 2001
From: Chris Lu <chris.lu@gmail.com>
Date: Sun, 27 Dec 2020 10:50:27 -0800
Subject: [PATCH] s3: add option for "alllowEmptyFolder"

---
 weed/command/s3.go                        | 17 ++++++++++-------
 weed/s3api/s3api_objects_list_handlers.go |  6 ++++--
 weed/s3api/s3api_server.go                |  1 +
 3 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/weed/command/s3.go b/weed/command/s3.go
index ed5bb0b80..d8e3e306b 100644
--- a/weed/command/s3.go
+++ b/weed/command/s3.go
@@ -23,13 +23,14 @@ var (
 )
 
 type S3Options struct {
-	filer           *string
-	port            *int
-	config          *string
-	domainName      *string
-	tlsPrivateKey   *string
-	tlsCertificate  *string
-	metricsHttpPort *int
+	filer            *string
+	port             *int
+	config           *string
+	domainName       *string
+	tlsPrivateKey    *string
+	tlsCertificate   *string
+	metricsHttpPort  *int
+	allowEmptyFolder *bool
 }
 
 func init() {
@@ -41,6 +42,7 @@ func init() {
 	s3StandaloneOptions.tlsPrivateKey = cmdS3.Flag.String("key.file", "", "path to the TLS private key file")
 	s3StandaloneOptions.tlsCertificate = cmdS3.Flag.String("cert.file", "", "path to the TLS certificate file")
 	s3StandaloneOptions.metricsHttpPort = cmdS3.Flag.Int("metricsPort", 0, "Prometheus metrics listen port")
+	s3StandaloneOptions.allowEmptyFolder = cmdS3.Flag.Bool("allowEmptyFolder", false, "allow empty folders")
 }
 
 var cmdS3 = &Command{
@@ -181,6 +183,7 @@ func (s3opt *S3Options) startS3Server() bool {
 		DomainName:       *s3opt.domainName,
 		BucketsPath:      filerBucketsPath,
 		GrpcDialOption:   grpcDialOption,
+		AllowEmptyFolder: *s3opt.allowEmptyFolder,
 	})
 	if s3ApiServer_err != nil {
 		glog.Fatalf("S3 API Server startup error: %v", s3ApiServer_err)
diff --git a/weed/s3api/s3api_objects_list_handlers.go b/weed/s3api/s3api_objects_list_handlers.go
index c1c6e2f89..fb1497b78 100644
--- a/weed/s3api/s3api_objects_list_handlers.go
+++ b/weed/s3api/s3api_objects_list_handlers.go
@@ -264,8 +264,10 @@ func (s3a *S3ApiServer) doListFilerEntries(client filer_pb.SeaweedFilerClient, d
 					}
 				} else {
 					var isEmpty bool
-					if isEmpty, err = s3a.isDirectoryAllEmpty(client, dir, entry.Name); err != nil {
-						glog.Errorf("check empty folder %s: %v", dir, err)
+					if !s3a.option.AllowEmptyFolder {
+						if isEmpty, err = s3a.isDirectoryAllEmpty(client, dir, entry.Name); err != nil {
+							glog.Errorf("check empty folder %s: %v", dir, err)
+						}
 					}
 					if !isEmpty {
 						eachEntryFn(dir, entry)
diff --git a/weed/s3api/s3api_server.go b/weed/s3api/s3api_server.go
index e4a07a443..4993104ae 100644
--- a/weed/s3api/s3api_server.go
+++ b/weed/s3api/s3api_server.go
@@ -20,6 +20,7 @@ type S3ApiServerOption struct {
 	DomainName       string
 	BucketsPath      string
 	GrpcDialOption   grpc.DialOption
+	AllowEmptyFolder bool
 }
 
 type S3ApiServer struct {