Address review comments

Author: abhijith-db

cmd/thanos/receive.go

@@ -1087,7 +1087,7 @@ func (rc *receiveConfig) registerFlag(cmd extkingpin.FlagClause) {
 
 	rc.relabelConfigPath = extflag.RegisterPathOrContent(cmd, "receive.relabel-config", "YAML file that contains relabeling configuration.", extflag.WithEnvSubstitution())
 	cmd.Flag("receive.relabel-config-reload-timer", "Minimum amount of time to pass for the relabel configuration to be reloaded. Helps to avoid excessive reloads.").
-		Default("1s").Hidden().DurationVar(&rc.relabelConfigReloadTimer)
+		Default("0s").Hidden().DurationVar(&rc.relabelConfigReloadTimer)
 
 	rc.tsdbMinBlockDuration = extkingpin.ModelDuration(cmd.Flag("tsdb.min-block-duration", "Min duration for local TSDB blocks").Default("2h").Hidden())
 

pkg/receive/relabeller.go

@@ -134,6 +134,9 @@ func (r *Relabeller) StartConfigReloader(ctx context.Context) error {
 }
 
 func (r *Relabeller) CanReload() bool {
+	if r.configReloadTimer == 0 {
+		return false
+	}
 	if r.configPathOrContent == nil {
 		return false
 	}

pkg/receive/relabeller_test.go

@@ -7,9 +7,12 @@ import (
 	"context"
 	"os"
 	"path"
+	"reflect"
 	"testing"
 	"time"
 
+	"github.com/stretchr/testify/require"
+
 	"gopkg.in/yaml.v2"
 
 	"github.com/thanos-io/thanos/pkg/extkingpin"
@@ -52,15 +55,17 @@ func TestRelabeller_ConfigReload(t *testing.T) {
 
 	// Rewrite the relabels file in temp with an invalid file, should not update the config.
 	testutil.Ok(t, relabelFile.Rewrite(invalidRelabels))
-	time.Sleep(1 * time.Second)
-	testutil.Equals(t, origRelabelsConfig, relabeller.RelabelConfig())
+	require.Never(t, func() bool {
+		return !reflect.DeepEqual(origRelabelsConfig, relabeller.RelabelConfig())
+	}, 3*time.Second, 100*time.Millisecond)
 
 	// Rewrite the relabels file in temp with a different valid file.
 	testutil.Ok(t, relabelFile.Rewrite(newRelabels))
 	newRelabelsConfig, err := parseRelabel("./testdata/relabel_config/good_relabels2.yaml")
 	testutil.Ok(t, err)
-	time.Sleep(1 * time.Second)
-	testutil.Equals(t, newRelabelsConfig, relabeller.RelabelConfig())
+	require.Eventually(t, func() bool {
+		return reflect.DeepEqual(newRelabelsConfig, relabeller.RelabelConfig())
+	}, 5*time.Second, 100*time.Millisecond)
 }
 
 func parseRelabel(path string) (RelabelConfig, error) {