Set notification namespace for NotificationConfiguration (#6789)

cmd/bucket-notification-handlers.go

@@ -83,6 +83,11 @@ func (api objectAPIHandlers) GetBucketNotificationHandler(w http.ResponseWriter,
 		nConfig = &event.Config{}
 	}
 
+	// If xml namespace is empty, set a default value before returning.
+	if nConfig.XMLNS == "" {
+		nConfig.XMLNS = "http://s3.amazonaws.com/doc/2006-03-01/"
+	}
+
 	notificationBytes, err := xml.Marshal(nConfig)
 	if err != nil {
 		logger.LogIf(ctx, err)

pkg/event/config.go

@@ -204,6 +204,7 @@ type topic struct {
 // Config - notification configuration described in
 // http://docs.aws.amazon.com/AmazonS3/latest/dev/NotificationHowTo.html
 type Config struct {
+	XMLNS      string   `xml:"xmlns,attr,omitempty"`
 	XMLName    xml.Name `xml:"NotificationConfiguration"`
 	QueueList  []Queue  `xml:"QueueConfiguration,omitempty"`
 	LambdaList []lambda `xml:"CloudFunctionConfiguration,omitempty"`