Chore: Enable Go linter gocritic (#26224)

* Chore: Enable gocritic linter

Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>

pkg/services/alerting/conditions/reducer.go

@@ -36,7 +36,7 @@ func (s *queryReducer) Reduce(series *tsdb.TimeSeries) null.Float {
 			}
 		}
 		if validPointsCount > 0 {
-			value = value / float64(validPointsCount)
+			value /= float64(validPointsCount)
 		}
 	case "sum":
 		for _, point := range series.Points {

pkg/services/alerting/engine.go

@@ -214,11 +214,12 @@ func (e *AlertEngine) processJob(attemptID int, attemptChan chan int, cancelChan
 		evalContext.Ctx = resultHandleCtx
 		evalContext.Rule.State = evalContext.GetNewState()
 		if err := e.resultHandler.handle(evalContext); err != nil {
-			if xerrors.Is(err, context.Canceled) {
+			switch {
+			case xerrors.Is(err, context.Canceled):
 				e.log.Debug("Result handler returned context.Canceled")
-			} else if xerrors.Is(err, context.DeadlineExceeded) {
+			case xerrors.Is(err, context.DeadlineExceeded):
 				e.log.Debug("Result handler returned context.DeadlineExceeded")
-			} else {
+			default:
 				e.log.Error("Failed to handle result", "err", err)
 			}
 		}

pkg/services/alerting/notifier.go

@@ -16,6 +16,7 @@ import (
 )
 
 // for stubbing in tests
+//nolint: gocritic
 var newImageUploaderProvider = func() (imguploader.ImageUploader, error) {
 	return imguploader.NewImageUploader()
 }

pkg/services/alerting/notifiers/kafka.go

@@ -85,7 +85,7 @@ func (kn *KafkaNotifier) Notify(evalContext *alerting.EvalContext) error {
 
 	customData := triggMetrString
 	for _, evt := range evalContext.EvalMatches {
-		customData = customData + fmt.Sprintf("%s: %v\n", evt.Metric, evt.Value)
+		customData += fmt.Sprintf("%s: %v\n", evt.Metric, evt.Value)
 	}
 
 	kn.log.Info("Notifying Kafka", "alert_state", state)

pkg/services/alerting/notifiers/line.go

@@ -67,13 +67,11 @@ type LineNotifier struct {
 // Notify send an alert notification to LINE
 func (ln *LineNotifier) Notify(evalContext *alerting.EvalContext) error {
 	ln.log.Info("Executing line notification", "ruleId", evalContext.Rule.ID, "notification", ln.Name)
-
-	var err error
-	switch evalContext.Rule.State {
-	case models.AlertStateAlerting:
-		err = ln.createAlert(evalContext)
+	if evalContext.Rule.State == models.AlertStateAlerting {
+		return ln.createAlert(evalContext)
 	}
-	return err
+
+	return nil
 }
 
 func (ln *LineNotifier) createAlert(evalContext *alerting.EvalContext) error {

pkg/services/alerting/notifiers/opsgenie.go

@@ -142,7 +142,7 @@ func (on *OpsGenieNotifier) createAlert(evalContext *alerting.EvalContext) error
 
 	customData := triggMetrString
 	for _, evt := range evalContext.EvalMatches {
-		customData = customData + fmt.Sprintf("%s: %v\n", evt.Metric, evt.Value)
+		customData += fmt.Sprintf("%s: %v\n", evt.Metric, evt.Value)
 	}
 
 	bodyJSON := simplejson.New()

pkg/services/alerting/notifiers/sensu.go

@@ -130,11 +130,12 @@ func (sn *SensuNotifier) Notify(evalContext *alerting.EvalContext) error {
 	bodyJSON.Set("output", "Grafana Metric Condition Met")
 	bodyJSON.Set("evalMatches", evalContext.EvalMatches)
 
-	if evalContext.Rule.State == "alerting" {
+	switch evalContext.Rule.State {
+	case "alerting":
 		bodyJSON.Set("status", 2)
-	} else if evalContext.Rule.State == "no_data" {
+	case "no_data":
 		bodyJSON.Set("status", 1)
-	} else {
+	default:
 		bodyJSON.Set("status", 0)
 	}
 

pkg/services/alerting/notifiers/telegram.go

@@ -125,16 +125,16 @@ func (tn *TelegramNotifier) buildMessageLinkedImage(evalContext *alerting.EvalCo
 
 	ruleURL, err := evalContext.GetRuleURL()
 	if err == nil {
-		message = message + fmt.Sprintf("URL: %s\n", ruleURL)
+		message += fmt.Sprintf("URL: %s\n", ruleURL)
 	}
 
 	if evalContext.ImagePublicURL != "" {
-		message = message + fmt.Sprintf("Image: %s\n", evalContext.ImagePublicURL)
+		message += fmt.Sprintf("Image: %s\n", evalContext.ImagePublicURL)
 	}
 
 	metrics := generateMetricsMessage(evalContext)
 	if metrics != "" {
-		message = message + fmt.Sprintf("\n<i>Metrics:</i>%s", metrics)
+		message += fmt.Sprintf("\n<i>Metrics:</i>%s", metrics)
 	}
 
 	return tn.generateTelegramCmd(message, "text", "sendMessage", func(w *multipart.Writer) {

pkg/services/alerting/notifiers/threema.go

@@ -177,10 +177,10 @@ func (notifier *ThreemaNotifier) Notify(evalContext *alerting.EvalContext) error
 		evalContext.Rule.Name, evalContext.Rule.Message)
 	ruleURL, err := evalContext.GetRuleURL()
 	if err == nil {
-		message = message + fmt.Sprintf("*URL:* %s\n", ruleURL)
+		message += fmt.Sprintf("*URL:* %s\n", ruleURL)
 	}
 	if notifier.NeedsImage() && evalContext.ImagePublicURL != "" {
-		message = message + fmt.Sprintf("*Image:* %s\n", evalContext.ImagePublicURL)
+		message += fmt.Sprintf("*Image:* %s\n", evalContext.ImagePublicURL)
 	}
 	data.Set("text", message)
 

pkg/services/alerting/result_handler.go

@@ -100,11 +100,12 @@ func (handler *defaultResultHandler) handle(evalContext *EvalContext) error {
 	}
 
 	if err := handler.notifier.SendIfNeeded(evalContext); err != nil {
-		if xerrors.Is(err, context.Canceled) {
+		switch {
+		case xerrors.Is(err, context.Canceled):
 			handler.log.Debug("handler.notifier.SendIfNeeded returned context.Canceled")
-		} else if xerrors.Is(err, context.DeadlineExceeded) {
+		case xerrors.Is(err, context.DeadlineExceeded):
 			handler.log.Debug("handler.notifier.SendIfNeeded returned context.DeadlineExceeded")
-		} else {
+		default:
 			handler.log.Error("handler.notifier.SendIfNeeded failed", "err", err)
 		}
 	}

pkg/services/alerting/rule.go

@@ -89,7 +89,7 @@ func getTimeDurationStringToSeconds(str string) (int64, error) {
 
 	matches := valueFormatRegex.FindAllString(str, 1)
 
-	if len(matches) <= 0 {
+	if len(matches) == 0 {
 		return 0, ErrFrequencyCouldNotBeParsed
 	}