s3: add option for "alllowEmptyFolder"

weed/command/s3.go

@@ -30,6 +30,7 @@ type S3Options struct {
 	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)

weed/s3api/s3api_objects_list_handlers.go

@@ -264,9 +264,11 @@ func (s3a *S3ApiServer) doListFilerEntries(client filer_pb.SeaweedFilerClient, d
 					}
 				} else {
 					var isEmpty bool
+					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)
 						counter++

weed/s3api/s3api_server.go

@@ -20,6 +20,7 @@ type S3ApiServerOption struct {
 	DomainName       string
 	BucketsPath      string
 	GrpcDialOption   grpc.DialOption
+	AllowEmptyFolder bool
 }
 
 type S3ApiServer struct {