From 9df4e4ee2992350192781a683bbfc453add1d18e Mon Sep 17 00:00:00 2001
From: Anis Elleuch <anis@min.io>
Date: Sat, 15 Apr 2023 16:18:58 +0100
Subject: [PATCH] listen bucket: Support empty events from the server

Ask the server to send empty events to clear the buffer scanner which
can be filled with whitespaces but without new lines when the bucket is
idle and without any events
---
 api-bucket-notification.go | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/api-bucket-notification.go b/api-bucket-notification.go
index dc37b0c07..6c9b4deb0 100644
--- a/api-bucket-notification.go
+++ b/api-bucket-notification.go
@@ -166,6 +166,7 @@ func (c *Client) ListenBucketNotification(ctx context.Context, bucketName, prefi
 
 		// Prepare urlValues to pass into the request on every loop
 		urlValues := make(url.Values)
+		urlValues.Set("ping", "true")
 		urlValues.Set("prefix", prefix)
 		urlValues.Set("suffix", suffix)
 		urlValues["events"] = events
@@ -224,6 +225,12 @@ func (c *Client) ListenBucketNotification(ctx context.Context, bucketName, prefi
 					closeResponse(resp)
 					continue
 				}
+
+				// Empty events pinged from the server
+				if len(notificationInfo.Records) == 0 && notificationInfo.Err == nil {
+					continue
+				}
+
 				// Send notificationInfo
 				select {
 				case notificationInfoCh <- notificationInfo: