From d3e89f164bf8a1c8f6bc788c42581349ac4618ac Mon Sep 17 00:00:00 2001
From: Alexander Narsudinov <a.narsudinov@gmail.com>
Date: Fri, 27 Oct 2023 20:05:02 +0200
Subject: [PATCH] Use atomics to make writing of results safe in
 `removeObjectsOneByOne`

Previous implementation didn't have any synchronization mechanism for
goroutines that does the work.

There are multiple approaches to make it work correctly, let's start with
the simplest - atomics.
---
 pkg/s3/client.go | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/pkg/s3/client.go b/pkg/s3/client.go
index 563c033..6e63e6d 100644
--- a/pkg/s3/client.go
+++ b/pkg/s3/client.go
@@ -5,6 +5,7 @@ import (
 	"context"
 	"fmt"
 	"net/url"
+	"sync/atomic"
 
 	"github.com/golang/glog"
 	"github.com/minio/minio-go/v7"
@@ -173,8 +174,8 @@ func (client *s3Client) removeObjectsOneByOne(bucketName, prefix string) error {
 	objectsCh := make(chan minio.ObjectInfo, 1)
 	guardCh := make(chan int, parallelism)
 	var listErr error
-	totalObjects := 0
-	removeErrors := 0
+	var totalObjects int64 = 0
+	var removeErrors int64 = 0
 
 	go func() {
 		defer close(objectsCh)
@@ -185,7 +186,7 @@ func (client *s3Client) removeObjectsOneByOne(bucketName, prefix string) error {
 				listErr = object.Err
 				return
 			}
-			totalObjects++
+			atomic.AddInt64(&totalObjects, 1)
 			objectsCh <- object
 		}
 	}()
@@ -202,7 +203,7 @@ func (client *s3Client) removeObjectsOneByOne(bucketName, prefix string) error {
 				minio.RemoveObjectOptions{VersionID: obj.VersionID})
 			if err != nil {
 				glog.Errorf("Failed to remove object %s, error: %s", obj.Key, err)
-				removeErrors++
+				atomic.AddInt64(&removeErrors, 1)
 			}
 			<- guardCh
 		}(object)