Add KEDAScalersInfo to display important information

Signed-off-by: rickbrouwer <[email protected]>

CHANGELOG.md

@@ -89,6 +89,7 @@ New deprecation(s):
 ### Other
 
 - **General**: Bump newrelic-client-go deps to 2.51.2 (latest) ([#6325](https://github.com/kedacore/keda/pull/6325))
+- **General**: New eventreason KEDAScalersInfo to display important information ([#6328](https://github.com/kedacore/keda/pull/6328))
 
 
 ## v2.16.0

pkg/eventreason/eventreason.go

@@ -41,6 +41,9 @@ const (
 	// ScaledJobDeleted is for event when ScaledJob is deleted
 	ScaledJobDeleted = "ScaledJobDeleted"
 
+	// KEDAScalersInfo is for event when Scaler has additional info
+	KEDAScalersInfo = "KEDAScalerInfo"
+
 	// KEDAScalersStarted is for event when scalers watch started for ScaledObject or ScaledJob
 	KEDAScalersStarted = "KEDAScalersStarted"
 

pkg/scalers/cpu_memory_scaler.go

@@ -18,6 +18,7 @@ type cpuMemoryScaler struct {
 	metadata     cpuMemoryMetadata
 	resourceName v1.ResourceName
 	logger       logr.Logger
+	info         string
 }
 
 type cpuMemoryMetadata struct {
@@ -33,19 +34,26 @@ type cpuMemoryMetadata struct {
 func NewCPUMemoryScaler(resourceName v1.ResourceName, config *scalersconfig.ScalerConfig) (Scaler, error) {
 	logger := InitializeLogger(config, "cpu_memory_scaler")
 
-	meta, err := parseResourceMetadata(config, logger)
+	meta, err := parseResourceMetadata(config)
 	if err != nil {
 		return nil, fmt.Errorf("error parsing %s metadata: %w", resourceName, err)
 	}
 
-	return &cpuMemoryScaler{
+	scaler := &cpuMemoryScaler{
 		metadata:     meta,
 		resourceName: resourceName,
 		logger:       logger,
-	}, nil
+	}
+
+	// This is deprecated and can be removed later
+	if meta.Type != "" {
+		scaler.info = "The 'type' setting is DEPRECATED and will be removed in v2.18 - Use 'metricType' instead."
+	}
+
+	return scaler, nil
 }
 
-func parseResourceMetadata(config *scalersconfig.ScalerConfig, logger logr.Logger) (cpuMemoryMetadata, error) {
+func parseResourceMetadata(config *scalersconfig.ScalerConfig) (cpuMemoryMetadata, error) {
 	meta := cpuMemoryMetadata{}
 	err := config.TypedConfig(&meta)
 	if err != nil {
@@ -58,7 +66,6 @@ func parseResourceMetadata(config *scalersconfig.ScalerConfig, logger logr.Logge
 
 	// This is deprecated and can be removed later
 	if meta.Type != "" {
-		logger.Info("The 'type' setting is DEPRECATED and will be removed in v2.18 - Use 'metricType' instead.")
 		switch meta.Type {
 		case "AverageValue":
 			meta.MetricType = v2.AverageValueMetricType
@@ -100,6 +107,10 @@ func (s *cpuMemoryScaler) Close(context.Context) error {
 	return nil
 }
 
+func (s *cpuMemoryScaler) GetScalerInfo() string {
+	return s.info
+}
+
 // GetMetricSpecForScaling returns the metric spec for the HPA
 func (s *cpuMemoryScaler) GetMetricSpecForScaling(context.Context) []v2.MetricSpec {
 	metricType := s.metadata.MetricType

pkg/scalers/ibmmq_scaler.go

@@ -23,6 +23,7 @@ type ibmmqScaler struct {
 	metadata   ibmmqMetadata
 	httpClient *http.Client
 	logger     logr.Logger
+	info       string
 }
 
 type ibmmqMetadata struct {
@@ -92,7 +93,6 @@ func NewIBMMQScaler(config *scalersconfig.ScalerConfig) (Scaler, error) {
 
 	// TODO: DEPRECATED to be removed in v2.18
 	if meta.TLS {
-		logger.Info("The 'tls' setting is DEPRECATED and will be removed in v2.18 - Use 'unsafeSsl' instead")
 		meta.UnsafeSsl = meta.TLS
 	}
 
@@ -106,12 +106,19 @@ func NewIBMMQScaler(config *scalersconfig.ScalerConfig) (Scaler, error) {
 		httpClient.Transport = kedautil.CreateHTTPTransportWithTLSConfig(tlsConfig)
 	}
 
-	return &ibmmqScaler{
+	scaler := &ibmmqScaler{
 		metricType: metricType,
 		metadata:   meta,
 		httpClient: httpClient,
 		logger:     logger,
-	}, nil
+	}
+
+	// TODO: DEPRECATED to be removed in v2.18
+	if meta.TLS {
+		scaler.info = "The 'tls' setting is DEPRECATED and will be removed in v2.18 - Use 'unsafeSsl' instead"
+	}
+
+	return scaler, nil
 }
 
 func (s *ibmmqScaler) Close(context.Context) error {
@@ -121,6 +128,10 @@ func (s *ibmmqScaler) Close(context.Context) error {
 	return nil
 }
 
+func (s *ibmmqScaler) GetScalerInfo() string {
+	return s.info
+}
+
 func parseIBMMQMetadata(config *scalersconfig.ScalerConfig) (ibmmqMetadata, error) {
 	meta := ibmmqMetadata{triggerIndex: config.TriggerIndex}
 	if err := config.TypedConfig(&meta); err != nil {

pkg/scalers/scaler.go

@@ -54,6 +54,11 @@ type Scaler interface {
 	Close(ctx context.Context) error
 }
 
+// InfoProvider is an optional interface that scalers can implement to provide additional information
+type InfoProvider interface {
+	GetScalerInfo() string
+}
+
 // PushScaler interface
 type PushScaler interface {
 	Scaler

pkg/scalers/scaler_test.go

@@ -1,16 +1,46 @@
 package scalers
 
 import (
+	"context"
 	"reflect"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 	v2 "k8s.io/api/autoscaling/v2"
 	"k8s.io/apimachinery/pkg/api/resource"
+	"k8s.io/metrics/pkg/apis/external_metrics"
 
 	scalersconfig "github.com/kedacore/keda/v2/pkg/scalers/scalersconfig"
 )
 
+type mockScaler struct {
+	info string
+}
+
+func (s *mockScaler) GetMetricSpecForScaling(context.Context) []v2.MetricSpec {
+	return nil
+}
+
+func (s *mockScaler) GetMetrics(context.Context, string) ([]external_metrics.ExternalMetricValue, error) {
+	return nil, nil
+}
+
+func (s *mockScaler) IsActive(context.Context) (bool, error) {
+	return false, nil
+}
+
+func (s *mockScaler) Close(context.Context) error {
+	return nil
+}
+
+func (s *mockScaler) GetMetricsAndActivity(context.Context, string) ([]external_metrics.ExternalMetricValue, bool, error) {
+	return nil, false, nil
+}
+
+func (s *mockScaler) GetScalerInfo() string {
+	return s.info
+}
+
 func TestGetMetricTargetType(t *testing.T) {
 	cases := []struct {
 		name           string
@@ -473,3 +503,41 @@ func TestConvertStringToType(t *testing.T) {
 		}
 	}
 }
+
+func TestScalerInfo(t *testing.T) {
+	cases := []struct {
+		name          string
+		scaler        Scaler
+		expectedInfo  string
+		expectingInfo bool
+	}{
+		{
+			name:          "scaler with info",
+			scaler:        &mockScaler{info: "test info message"},
+			expectedInfo:  "test info message",
+			expectingInfo: true,
+		},
+		{
+			name:          "scaler with empty info",
+			scaler:        &mockScaler{info: ""},
+			expectedInfo:  "",
+			expectingInfo: false,
+		},
+	}
+
+	for _, testCase := range cases {
+		tc := testCase
+		t.Run(tc.name, func(t *testing.T) {
+			if infoProvider, ok := tc.scaler.(InfoProvider); ok {
+				info := infoProvider.GetScalerInfo()
+				if tc.expectingInfo {
+					assert.Equal(t, tc.expectedInfo, info)
+				} else {
+					assert.Empty(t, info)
+				}
+			} else {
+				t.Error("Scaler does not implement InfoProvider interface")
+			}
+		})
+	}
+}

pkg/scaling/scalers_builder.go

@@ -102,6 +102,13 @@ func (h *scaleHandler) buildScalers(ctx context.Context, withTriggers *kedav1alp
 		msg := fmt.Sprintf(message.ScalerIsBuiltMsg, trigger.Type)
 		h.recorder.Event(withTriggers, corev1.EventTypeNormal, eventreason.KEDAScalersStarted, msg)
 
+		if infoProvider, ok := scaler.(scalers.InfoProvider); ok {
+			if info := infoProvider.GetScalerInfo(); info != "" {
+				infoMsg := fmt.Sprintf("Scaler %s additional info: %s", trigger.Type, info)
+				h.recorder.Event(withTriggers, corev1.EventTypeNormal, eventreason.KEDAScalersInfo, infoMsg)
+			}
+		}
+
 		result = append(result, cache.ScalerBuilder{
 			Scaler:       scaler,
 			ScalerConfig: *config,