Cleanup logging test in clusterloader

Author: wojtek-t

clusterloader2/pkg/measurement/common/slos/api_responsiveness_prometheus_test.go

@@ -19,7 +19,6 @@ package slos
 import (
 	"bytes"
 	"encoding/json"
-	"flag"
 	"fmt"
 	"strings"
 	"testing"
@@ -32,34 +31,12 @@ import (
 	"k8s.io/perf-tests/clusterloader2/pkg/measurement"
 	"k8s.io/perf-tests/clusterloader2/pkg/measurement/common/executors"
 	measurementutil "k8s.io/perf-tests/clusterloader2/pkg/measurement/util"
-
-	_ "k8s.io/perf-tests/clusterloader2/pkg/flags" // init klog
-)
-
-var (
-	// klogv1 allows users to turn on/off logging to stderr only through
-	// the use of flag. This prevents us from having control over which
-	// of the test functions have that mechanism turned off when we run
-	// go test command.
-	// TODO(#1286): refactor api_responsiveness_prometheus.go to make
-	// testing of logging easier and remove this hack in the end.
-	klogLogToStderr = true
 )
 
-func turnOffLoggingToStderrInKlog(t *testing.T) {
-	if klogLogToStderr {
-		err := flag.Set("logtostderr", "false")
-		if err != nil {
-			t.Errorf("Unable to set flag %v", err)
-			return
-		}
-		err = flag.Set("v", "2")
-		if err != nil {
-			t.Errorf("Unable to set flag %v", err)
-			return
-		}
-		flag.Parse()
-		klogLogToStderr = false
+func changeLoggingVerbosity(t *testing.T, logLevel string) {
+	var level klog.Level
+	if err := level.Set(logLevel); err != nil {
+		t.Errorf("Unable to set flag %v", err)
 	}
 }
 
@@ -574,7 +551,9 @@ func TestLogging(t *testing.T) {
 		},
 	}
 
-	turnOffLoggingToStderrInKlog(t)
+	klog.LogToStderr(false)
+	defer klog.LogToStderr(true)
+	changeLoggingVerbosity(t, "2")
 
 	for _, tc := range cases {
 		t.Run(tc.name, func(t *testing.T) {
@@ -763,7 +742,9 @@ func TestAPIResponsivenessCustomThresholds(t *testing.T) {
 		},
 	}
 
-	turnOffLoggingToStderrInKlog(t)
+	klog.LogToStderr(false)
+	defer klog.LogToStderr(true)
+	changeLoggingVerbosity(t, "2")
 
 	for _, tc := range cases {
 		t.Run(tc.name, func(t *testing.T) {