fix lint

cmd/healthchecker/health_checker.go

@@ -39,8 +39,16 @@ func main() {
 		}
 	})
 	pflag.CommandLine.AddGoFlagSet(flag.CommandLine)
-	pflag.CommandLine.MarkHidden("vmodule")
-	pflag.CommandLine.MarkHidden("logtostderr")
+	err := pflag.CommandLine.MarkHidden("vmodule")
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(int(types.Unknown))
+	}
+	err = pflag.CommandLine.MarkHidden("logtostderr")
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(int(types.Unknown))
+	}
 
 	hco := options.NewHealthCheckerOptions()
 	hco.AddFlags(pflag.CommandLine)

cmd/healthchecker/options/options.go

@@ -52,7 +52,7 @@ func (hco *HealthCheckerOptions) AddFlags(fs *pflag.FlagSet) {
 		"The component to check health for. Supports kubelet, docker, kube-proxy, and cri")
 	// Deprecated: For backward compatibility on linux environment. Going forward "service" will be used instead of systemd-service
 	if runtime.GOOS == "linux" {
-		fs.MarkDeprecated("systemd-service", "please use --service flag instead")
+		_ = fs.MarkDeprecated("systemd-service", "please use --service flag instead")
 		fs.StringVar(&hco.Service, "systemd-service", "",
 			"The underlying service responsible for the component. Set to the corresponding component for docker and kubelet, containerd for cri.")
 	}

cmd/nodeproblemdetector/node_problem_detector_unix.go

@@ -37,8 +37,8 @@ func main() {
 		}
 	})
 	pflag.CommandLine.AddGoFlagSet(flag.CommandLine)
-	pflag.CommandLine.MarkHidden("vmodule")
-	pflag.CommandLine.MarkHidden("logtostderr")
+	_ = pflag.CommandLine.MarkHidden("vmodule")
+	_ = pflag.CommandLine.MarkHidden("logtostderr")
 
 	npdo := options.NewNodeProblemDetectorOptions()
 	npdo.AddFlags(pflag.CommandLine)

cmd/options/options.go

@@ -102,10 +102,10 @@ func NewNodeProblemDetectorOptions() *NodeProblemDetectorOptions {
 func (npdo *NodeProblemDetectorOptions) AddFlags(fs *pflag.FlagSet) {
 	fs.StringSliceVar(&npdo.SystemLogMonitorConfigPaths, "system-log-monitors",
 		[]string{}, "List of paths to system log monitor config files, comma separated.")
-	fs.MarkDeprecated("system-log-monitors", "replaced by --config.system-log-monitor. NPD will panic if both --system-log-monitors and --config.system-log-monitor are set.")
+	_ = fs.MarkDeprecated("system-log-monitors", "replaced by --config.system-log-monitor. NPD will panic if both --system-log-monitors and --config.system-log-monitor are set.")
 	fs.StringSliceVar(&npdo.CustomPluginMonitorConfigPaths, "custom-plugin-monitors",
 		[]string{}, "List of paths to custom plugin monitor config files, comma separated.")
-	fs.MarkDeprecated("custom-plugin-monitors", "replaced by --config.custom-plugin-monitor. NPD will panic if both --custom-plugin-monitors and --config.custom-plugin-monitor are set.")
+	_ = fs.MarkDeprecated("custom-plugin-monitors", "replaced by --config.custom-plugin-monitor. NPD will panic if both --custom-plugin-monitors and --config.custom-plugin-monitor are set.")
 	fs.BoolVar(&npdo.EnableK8sExporter, "enable-k8s-exporter", true, "Enables reporting to Kubernetes API server.")
 	fs.StringVar(&npdo.EventNamespace, "event-namespace", "", "Namespace for recorded Kubernetes events.")
 	fs.StringVar(&npdo.ApiServerOverride, "apiserver-override",

pkg/custompluginmonitor/plugin/plugin_test.go

@@ -103,7 +103,10 @@ func TestNewPluginRun(t *testing.T) {
 		utMeta := v
 		t.Run(desp, func(t *testing.T) {
 			conf := cpmtypes.CustomPluginConfig{}
-			(&conf).ApplyConfiguration()
+			err := (&conf).ApplyConfiguration()
+			if err != nil {
+				t.Errorf("Error in applying configuration: %v", err)
+			}
 			p := Plugin{config: conf}
 			gotExitStatus, gotOutput := p.run(utMeta.Rule)
 			// cut at position max_output_length if expected output is longer than max_output_length bytes

pkg/custompluginmonitor/types/config_test.go

@@ -218,7 +218,10 @@ func TestCustomPluginConfigApplyConfiguration(t *testing.T) {
 	}
 
 	for desp, utMeta := range utMetas {
-		(&utMeta.Orig).ApplyConfiguration()
+		err := (&utMeta.Orig).ApplyConfiguration()
+		if err != nil {
+			t.Errorf("Error in apply configuration for %q. Error: %v", desp, err)
+		}
 		if !reflect.DeepEqual(utMeta.Orig, utMeta.Wanted) {
 			t.Errorf("Error in apply configuration for %q", desp)
 			t.Errorf("Wanted: %+v. \nGot: %+v", utMeta.Wanted, utMeta.Orig)

pkg/exporters/k8sexporter/k8s_exporter.go

@@ -87,7 +87,7 @@ func (ke *k8sExporter) startHTTPReporting(npdo *options.NodeProblemDetectorOptio
 	// logic in the future.
 	mux.HandleFunc("/healthz", func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)
-		w.Write([]byte("ok"))
+		_, _ = w.Write([]byte("ok"))
 	})
 
 	// Add the handler to serve condition http request.

pkg/exporters/prometheusexporter/prometheus_exporter.go

@@ -56,5 +56,4 @@ func NewExporterOrDie(npdo *options.NodeProblemDetectorOptions) types.Exporter {
 // ExportProblems does nothing.
 // Prometheus exporter only exports metrics.
 func (pe *prometheusExporter) ExportProblems(status *types.Status) {
-	return
 }

pkg/exporters/stackdriver/stackdriver_exporter.go

@@ -186,7 +186,6 @@ func (se *stackdriverExporter) populateMetadataOrDie() {
 // ExportProblems does nothing.
 // Stackdriver exporter only exports metrics.
 func (se *stackdriverExporter) ExportProblems(status *types.Status) {
-	return
 }
 
 type commandLineOptions struct {

pkg/problemmetrics/problem_metrics_test.go

@@ -118,7 +118,10 @@ func TestNewProblem(t *testing.T) {
 			pmm, fakeProblemCounter, fakeProblemGauge := NewProblemMetricsManagerStub()
 
 			for idx, reason := range test.reasons {
-				pmm.IncrementProblemCounter(reason, test.counts[idx])
+				err := pmm.IncrementProblemCounter(reason, test.counts[idx])
+				if err != nil {
+					t.Fatalf("failed to increment problem counter: %v", err)
+				}
 			}
 
 			gotMetrics := append(fakeProblemCounter.ListMetrics(), fakeProblemGauge.ListMetrics()...)
@@ -266,7 +269,10 @@ func TestSetProblemGauge(t *testing.T) {
 			pmm, fakeProblemCounter, fakeProblemGauge := NewProblemMetricsManagerStub()
 
 			for _, argument := range test.arguments {
-				pmm.SetProblemGauge(argument.problemType, argument.reason, argument.value)
+				err := pmm.SetProblemGauge(argument.problemType, argument.reason, argument.value)
+				if err != nil {
+					t.Fatalf("failed to set problem gauge: %v", err)
+				}
 			}
 
 			gotMetrics := append(fakeProblemCounter.ListMetrics(), fakeProblemGauge.ListMetrics()...)

pkg/systemlogmonitor/log_buffer.go

@@ -47,8 +47,8 @@ type logBuffer struct {
 // lines of patterns we support.
 func NewLogBuffer(maxLines int) *logBuffer {
 	return &logBuffer{
-		buffer: make([]*types.Log, maxLines, maxLines),
-		msg:    make([]string, maxLines, maxLines),
+		buffer: make([]*types.Log, maxLines),
+		msg:    make([]string, maxLines),
 		max:    maxLines,
 	}
 }

pkg/systemstatsmonitor/cpu_collector.go

@@ -187,34 +187,34 @@ func (cc *cpuCollector) recordUsage() {
 	}
 	timersStat := timersStats[0]
 
-	cc.mUsageTime.Record(map[string]string{stateLabel: "user"}, clockTick*timersStat.User-cc.lastUsageTime["user"])
+	_ = cc.mUsageTime.Record(map[string]string{stateLabel: "user"}, clockTick*timersStat.User-cc.lastUsageTime["user"])
 	cc.lastUsageTime["user"] = clockTick * timersStat.User
 
-	cc.mUsageTime.Record(map[string]string{stateLabel: "system"}, clockTick*timersStat.System-cc.lastUsageTime["system"])
+	_ = cc.mUsageTime.Record(map[string]string{stateLabel: "system"}, clockTick*timersStat.System-cc.lastUsageTime["system"])
 	cc.lastUsageTime["system"] = clockTick * timersStat.System
 
-	cc.mUsageTime.Record(map[string]string{stateLabel: "idle"}, clockTick*timersStat.Idle-cc.lastUsageTime["idle"])
+	_ = cc.mUsageTime.Record(map[string]string{stateLabel: "idle"}, clockTick*timersStat.Idle-cc.lastUsageTime["idle"])
 	cc.lastUsageTime["idle"] = clockTick * timersStat.Idle
 
-	cc.mUsageTime.Record(map[string]string{stateLabel: "nice"}, clockTick*timersStat.Nice-cc.lastUsageTime["nice"])
+	_ = cc.mUsageTime.Record(map[string]string{stateLabel: "nice"}, clockTick*timersStat.Nice-cc.lastUsageTime["nice"])
 	cc.lastUsageTime["nice"] = clockTick * timersStat.Nice
 
-	cc.mUsageTime.Record(map[string]string{stateLabel: "iowait"}, clockTick*timersStat.Iowait-cc.lastUsageTime["iowait"])
+	_ = cc.mUsageTime.Record(map[string]string{stateLabel: "iowait"}, clockTick*timersStat.Iowait-cc.lastUsageTime["iowait"])
 	cc.lastUsageTime["iowait"] = clockTick * timersStat.Iowait
 
-	cc.mUsageTime.Record(map[string]string{stateLabel: "irq"}, clockTick*timersStat.Irq-cc.lastUsageTime["irq"])
+	_ = cc.mUsageTime.Record(map[string]string{stateLabel: "irq"}, clockTick*timersStat.Irq-cc.lastUsageTime["irq"])
 	cc.lastUsageTime["irq"] = clockTick * timersStat.Irq
 
-	cc.mUsageTime.Record(map[string]string{stateLabel: "softirq"}, clockTick*timersStat.Softirq-cc.lastUsageTime["softirq"])
+	_ = cc.mUsageTime.Record(map[string]string{stateLabel: "softirq"}, clockTick*timersStat.Softirq-cc.lastUsageTime["softirq"])
 	cc.lastUsageTime["softirq"] = clockTick * timersStat.Softirq
 
-	cc.mUsageTime.Record(map[string]string{stateLabel: "steal"}, clockTick*timersStat.Steal-cc.lastUsageTime["steal"])
+	_ = cc.mUsageTime.Record(map[string]string{stateLabel: "steal"}, clockTick*timersStat.Steal-cc.lastUsageTime["steal"])
 	cc.lastUsageTime["steal"] = clockTick * timersStat.Steal
 
-	cc.mUsageTime.Record(map[string]string{stateLabel: "guest"}, clockTick*timersStat.Guest-cc.lastUsageTime["guest"])
+	_ = cc.mUsageTime.Record(map[string]string{stateLabel: "guest"}, clockTick*timersStat.Guest-cc.lastUsageTime["guest"])
 	cc.lastUsageTime["guest"] = clockTick * timersStat.Guest
 
-	cc.mUsageTime.Record(map[string]string{stateLabel: "guest_nice"}, clockTick*timersStat.GuestNice-cc.lastUsageTime["guest_nice"])
+	_ = cc.mUsageTime.Record(map[string]string{stateLabel: "guest_nice"}, clockTick*timersStat.GuestNice-cc.lastUsageTime["guest_nice"])
 	cc.lastUsageTime["guest_nice"] = clockTick * timersStat.GuestNice
 }
 

pkg/systemstatsmonitor/cpu_collector_unix.go

@@ -40,16 +40,16 @@ func (cc *cpuCollector) recordLoad() {
 	}
 
 	if cc.mRunnableTaskCount != nil {
-		cc.mRunnableTaskCount.Record(map[string]string{}, loadAvg.Load1)
+		_ = cc.mRunnableTaskCount.Record(map[string]string{}, loadAvg.Load1)
 	}
 	if cc.mCpuLoad1m != nil {
-		cc.mCpuLoad1m.Record(map[string]string{}, loadAvg.Load1)
+		_ = cc.mCpuLoad1m.Record(map[string]string{}, loadAvg.Load1)
 	}
 	if cc.mCpuLoad5m != nil {
-		cc.mCpuLoad5m.Record(map[string]string{}, loadAvg.Load5)
+		_ = cc.mCpuLoad5m.Record(map[string]string{}, loadAvg.Load5)
 	}
 	if cc.mCpuLoad15m != nil {
-		cc.mCpuLoad15m.Record(map[string]string{}, loadAvg.Load15)
+		_ = cc.mCpuLoad15m.Record(map[string]string{}, loadAvg.Load15)
 	}
 }
 
@@ -62,26 +62,30 @@ func (cc *cpuCollector) recordSystemStats() {
 	}
 
 	fs, err := procfs.NewFS(cc.procPath)
+	if err != nil {
+		klog.Errorf("Failed to open procfs: %v", err)
+		return
+	}
 	stats, err := fs.Stat()
 	if err != nil {
 		klog.Errorf("Failed to retrieve cpu/process stats: %v", err)
 		return
 	}
 
 	if cc.mSystemProcessesTotal != nil {
-		cc.mSystemProcessesTotal.Record(map[string]string{}, int64(stats.ProcessCreated))
+		_ = cc.mSystemProcessesTotal.Record(map[string]string{}, int64(stats.ProcessCreated))
 	}
 
 	if cc.mSystemProcsRunning != nil {
-		cc.mSystemProcsRunning.Record(map[string]string{}, int64(stats.ProcessesRunning))
+		_ = cc.mSystemProcsRunning.Record(map[string]string{}, int64(stats.ProcessesRunning))
 	}
 
 	if cc.mSystemProcsBlocked != nil {
-		cc.mSystemProcsBlocked.Record(map[string]string{}, int64(stats.ProcessesBlocked))
+		_ = cc.mSystemProcsBlocked.Record(map[string]string{}, int64(stats.ProcessesBlocked))
 	}
 
 	if cc.mSystemInterruptsTotal != nil {
-		cc.mSystemInterruptsTotal.Record(map[string]string{}, int64(stats.IRQTotal))
+		_ = cc.mSystemInterruptsTotal.Record(map[string]string{}, int64(stats.IRQTotal))
 	}
 
 	if cc.mSystemCPUStat != nil {
@@ -90,25 +94,25 @@ func (cc *cpuCollector) recordSystemStats() {
 			tags[cpuLabel] = fmt.Sprintf("cpu%d", i)
 
 			tags[stageLabel] = "user"
-			cc.mSystemCPUStat.Record(tags, c.User)
+			_ = cc.mSystemCPUStat.Record(tags, c.User)
 			tags[stageLabel] = "nice"
-			cc.mSystemCPUStat.Record(tags, c.Nice)
+			_ = cc.mSystemCPUStat.Record(tags, c.Nice)
 			tags[stageLabel] = "system"
-			cc.mSystemCPUStat.Record(tags, c.System)
+			_ = cc.mSystemCPUStat.Record(tags, c.System)
 			tags[stageLabel] = "idle"
-			cc.mSystemCPUStat.Record(tags, c.Idle)
+			_ = cc.mSystemCPUStat.Record(tags, c.Idle)
 			tags[stageLabel] = "iowait"
-			cc.mSystemCPUStat.Record(tags, c.Iowait)
+			_ = cc.mSystemCPUStat.Record(tags, c.Iowait)
 			tags[stageLabel] = "iRQ"
-			cc.mSystemCPUStat.Record(tags, c.IRQ)
+			_ = cc.mSystemCPUStat.Record(tags, c.IRQ)
 			tags[stageLabel] = "softIRQ"
-			cc.mSystemCPUStat.Record(tags, c.SoftIRQ)
+			_ = cc.mSystemCPUStat.Record(tags, c.SoftIRQ)
 			tags[stageLabel] = "steal"
-			cc.mSystemCPUStat.Record(tags, c.Steal)
+			_ = cc.mSystemCPUStat.Record(tags, c.Steal)
 			tags[stageLabel] = "guest"
-			cc.mSystemCPUStat.Record(tags, c.Guest)
+			_ = cc.mSystemCPUStat.Record(tags, c.Guest)
 			tags[stageLabel] = "guestNice"
-			cc.mSystemCPUStat.Record(tags, c.GuestNice)
+			_ = cc.mSystemCPUStat.Record(tags, c.GuestNice)
 		}
 	}
 }

pkg/systemstatsmonitor/disk_collector.go

@@ -188,10 +188,10 @@ func (dc *diskCollector) recordIOCounters(ioCountersStats map[string]disk.IOCoun
 		dc.lastWeightedIO[deviceName] = ioCountersStat.WeightedIO
 
 		if dc.mIOTime != nil {
-			dc.mIOTime.Record(tags, int64(ioCountersStat.IoTime-lastIOTime))
+			_ = dc.mIOTime.Record(tags, int64(ioCountersStat.IoTime-lastIOTime))
 		}
 		if dc.mWeightedIO != nil {
-			dc.mWeightedIO.Record(tags, int64(ioCountersStat.WeightedIO-lastWeightedIO))
+			_ = dc.mWeightedIO.Record(tags, int64(ioCountersStat.WeightedIO-lastWeightedIO))
 		}
 		if historyExist {
 			avgQueueLen := float64(0.0)
@@ -200,47 +200,47 @@ func (dc *diskCollector) recordIOCounters(ioCountersStats map[string]disk.IOCoun
 				avgQueueLen = float64(ioCountersStat.WeightedIO-lastWeightedIO) / diffSampleTimeMs
 			}
 			if dc.mAvgQueueLen != nil {
-				dc.mAvgQueueLen.Record(tags, avgQueueLen)
+				_ = dc.mAvgQueueLen.Record(tags, avgQueueLen)
 			}
 		}
 
 		// Attach label {"device_name": deviceName, "direction": "read"} to the following metrics.
 		tags = map[string]string{deviceNameLabel: deviceName, directionLabel: "read"}
 
 		if dc.mOpsCount != nil {
-			dc.mOpsCount.Record(tags, int64(ioCountersStat.ReadCount-dc.lastReadCount[deviceName]))
+			_ = dc.mOpsCount.Record(tags, int64(ioCountersStat.ReadCount-dc.lastReadCount[deviceName]))
 			dc.lastReadCount[deviceName] = ioCountersStat.ReadCount
 		}
 		if dc.mMergedOpsCount != nil {
-			dc.mMergedOpsCount.Record(tags, int64(ioCountersStat.MergedReadCount-dc.lastMergedReadCount[deviceName]))
+			_ = dc.mMergedOpsCount.Record(tags, int64(ioCountersStat.MergedReadCount-dc.lastMergedReadCount[deviceName]))
 			dc.lastMergedReadCount[deviceName] = ioCountersStat.MergedReadCount
 		}
 		if dc.mOpsBytes != nil {
-			dc.mOpsBytes.Record(tags, int64(ioCountersStat.ReadBytes-dc.lastReadBytes[deviceName]))
+			_ = dc.mOpsBytes.Record(tags, int64(ioCountersStat.ReadBytes-dc.lastReadBytes[deviceName]))
 			dc.lastReadBytes[deviceName] = ioCountersStat.ReadBytes
 		}
 		if dc.mOpsTime != nil {
-			dc.mOpsTime.Record(tags, int64(ioCountersStat.ReadTime-dc.lastReadTime[deviceName]))
+			_ = dc.mOpsTime.Record(tags, int64(ioCountersStat.ReadTime-dc.lastReadTime[deviceName]))
 			dc.lastReadTime[deviceName] = ioCountersStat.ReadTime
 		}
 
 		// Attach label {"device_name": deviceName, "direction": "write"} to the following metrics.
 		tags = map[string]string{deviceNameLabel: deviceName, directionLabel: "write"}
 
 		if dc.mOpsCount != nil {
-			dc.mOpsCount.Record(tags, int64(ioCountersStat.WriteCount-dc.lastWriteCount[deviceName]))
+			_ = dc.mOpsCount.Record(tags, int64(ioCountersStat.WriteCount-dc.lastWriteCount[deviceName]))
 			dc.lastWriteCount[deviceName] = ioCountersStat.WriteCount
 		}
 		if dc.mMergedOpsCount != nil {
-			dc.mMergedOpsCount.Record(tags, int64(ioCountersStat.MergedWriteCount-dc.lastMergedWriteCount[deviceName]))
+			_ = dc.mMergedOpsCount.Record(tags, int64(ioCountersStat.MergedWriteCount-dc.lastMergedWriteCount[deviceName]))
 			dc.lastMergedWriteCount[deviceName] = ioCountersStat.MergedWriteCount
 		}
 		if dc.mOpsBytes != nil {
-			dc.mOpsBytes.Record(tags, int64(ioCountersStat.WriteBytes-dc.lastWriteBytes[deviceName]))
+			_ = dc.mOpsBytes.Record(tags, int64(ioCountersStat.WriteBytes-dc.lastWriteBytes[deviceName]))
 			dc.lastWriteBytes[deviceName] = ioCountersStat.WriteBytes
 		}
 		if dc.mOpsTime != nil {
-			dc.mOpsTime.Record(tags, int64(ioCountersStat.WriteTime-dc.lastWriteTime[deviceName]))
+			_ = dc.mOpsTime.Record(tags, int64(ioCountersStat.WriteTime-dc.lastWriteTime[deviceName]))
 			dc.lastWriteTime[deviceName] = ioCountersStat.WriteTime
 		}
 	}
@@ -301,10 +301,10 @@ func (dc *diskCollector) collect() {
 		deviceName := strings.TrimPrefix(partition.Device, "/dev/")
 		fstype := partition.Fstype
 		opttypes := strings.Join(partition.Opts, ",")
-		dc.mBytesUsed.Record(map[string]string{deviceNameLabel: deviceName, fsTypeLabel: fstype, mountOptionLabel: opttypes, stateLabel: "free"}, int64(usageStat.Free))
-		dc.mBytesUsed.Record(map[string]string{deviceNameLabel: deviceName, fsTypeLabel: fstype, mountOptionLabel: opttypes, stateLabel: "used"}, int64(usageStat.Used))
+		_ = dc.mBytesUsed.Record(map[string]string{deviceNameLabel: deviceName, fsTypeLabel: fstype, mountOptionLabel: opttypes, stateLabel: "free"}, int64(usageStat.Free))
+		_ = dc.mBytesUsed.Record(map[string]string{deviceNameLabel: deviceName, fsTypeLabel: fstype, mountOptionLabel: opttypes, stateLabel: "used"}, int64(usageStat.Used))
 		if dc.mPercentUsed != nil {
-			dc.mPercentUsed.Record(map[string]string{deviceNameLabel: deviceName, fsTypeLabel: fstype, mountOptionLabel: opttypes, stateLabel: "used"}, float64(usageStat.UsedPercent))
+			_ = dc.mPercentUsed.Record(map[string]string{deviceNameLabel: deviceName, fsTypeLabel: fstype, mountOptionLabel: opttypes, stateLabel: "used"}, float64(usageStat.UsedPercent))
 		}
 	}
 

pkg/systemstatsmonitor/host_collector.go

@@ -74,6 +74,6 @@ func (hc *hostCollector) collect() {
 	}
 
 	if hc.uptime != nil {
-		hc.uptime.Record(hc.tags, int64(uptime))
+		_ = hc.uptime.Record(hc.tags, int64(uptime))
 	}
 }