From e53d2032fe5a13dc682caa77e4a8c9cdf06ba4a2 Mon Sep 17 00:00:00 2001
From: Sandeep Sukhani <sandeep.d.sukhani@gmail.com>
Date: Thu, 10 Sep 2020 17:21:22 +0530
Subject: [PATCH] fix a panic when trying to stop boltdb-shipper multiple times
 using sync.once (#2613)

---
 pkg/storage/store_test.go                          | 2 ++
 pkg/storage/stores/shipper/shipper_index_client.go | 8 +++++++-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/pkg/storage/store_test.go b/pkg/storage/store_test.go
index 816ace012e51..e346806d7483 100644
--- a/pkg/storage/store_test.go
+++ b/pkg/storage/store_test.go
@@ -782,6 +782,8 @@ func TestStore_MultipleBoltDBShippersInConfig(t *testing.T) {
 	}}, limits, nil)
 	require.NoError(t, err)
 
+	defer store.Stop()
+
 	// time ranges adding a chunk for each store and a chunk which overlaps both the stores
 	chunksToBuildForTimeRanges := []timeRange{
 		{
diff --git a/pkg/storage/stores/shipper/shipper_index_client.go b/pkg/storage/stores/shipper/shipper_index_client.go
index a3444a67b948..647f7866b340 100644
--- a/pkg/storage/stores/shipper/shipper_index_client.go
+++ b/pkg/storage/stores/shipper/shipper_index_client.go
@@ -7,6 +7,7 @@ import (
 	"io/ioutil"
 	"os"
 	"path"
+	"sync"
 	"time"
 
 	"github.com/cortexproject/cortex/pkg/chunk"
@@ -76,7 +77,8 @@ type Shipper struct {
 	uploadsManager    *uploads.TableManager
 	downloadsManager  *downloads.TableManager
 
-	metrics *metrics
+	metrics  *metrics
+	stopOnce sync.Once
 }
 
 // NewShipper creates a shipper for syncing local objects with a store
@@ -179,6 +181,10 @@ func (s *Shipper) getUploaderName() (string, error) {
 }
 
 func (s *Shipper) Stop() {
+	s.stopOnce.Do(s.stop)
+}
+
+func (s *Shipper) stop() {
 	if s.uploadsManager != nil {
 		s.uploadsManager.Stop()
 	}