fix: Condition of queueLength for Selenium Grid scaler will scale up

Signed-off-by: Viet Nguyen Duc <[email protected]>
NDViet · Nov 26, 2024 · 477aa89 · 477aa89
1 parent 29400ed
commit 477aa89
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Showing 3 changed files with 28 additions and 25 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -68,7 +68,7 @@ Here is an overview of all new **experimental** features:
 
 ### Improvements
 
-- TODO ([#XXX](https://github.com/kedacore/keda/issues/XXX))
+- **Selenium Grid Scaler**: Fix: Condition of queueLength for Selenium Grid scaler will scale up
 
 ### Fixes
 

diff --git a/pkg/scalers/selenium_grid_scaler.go b/pkg/scalers/selenium_grid_scaler.go
@@ -40,8 +40,7 @@ type seleniumGridScalerMetadata struct {
 	UnsafeSsl           bool   `keda:"name=unsafeSsl,                order=triggerMetadata, optional, default=false"`
 	PlatformName        string `keda:"name=platformName,             order=triggerMetadata, optional, default=linux"`
 	NodeMaxSessions     int    `keda:"name=nodeMaxSessions,          order=triggerMetadata, optional, default=1"`
-
-	TargetValue int64
+	TargetQueueLength   int64  `keda:"name=targetQueueLength,        order=triggerMetadata;resolvedEnv, optional, default=1"`
 }
 
 type SeleniumResponse struct {
@@ -107,7 +106,8 @@ type Stereotypes []struct {
 }
 
 const (
-	DefaultBrowserVersion string = "latest"
+	DefaultBrowserVersion    string = "latest"
+	DefaultTargetQueueLength int64  = 1
 )
 
 func NewSeleniumGridScaler(config *scalersconfig.ScalerConfig) (Scaler, error) {
@@ -135,9 +135,7 @@ func NewSeleniumGridScaler(config *scalersconfig.ScalerConfig) (Scaler, error) {
 }
 
 func parseSeleniumGridScalerMetadata(config *scalersconfig.ScalerConfig) (*seleniumGridScalerMetadata, error) {
-	meta := &seleniumGridScalerMetadata{
-		TargetValue: 1,
-	}
+	meta := &seleniumGridScalerMetadata{}
 
 	if err := config.TypedConfig(meta); err != nil {
 		return nil, fmt.Errorf("error parsing prometheus metadata: %w", err)
@@ -148,6 +146,10 @@ func parseSeleniumGridScalerMetadata(config *scalersconfig.ScalerConfig) (*selen
 	if meta.SessionBrowserName == "" {
 		meta.SessionBrowserName = meta.BrowserName
 	}
+
+	if meta.TargetQueueLength < 1 {
+		meta.TargetQueueLength = DefaultTargetQueueLength
+	}
 	return meta, nil
 }
 
@@ -160,31 +162,32 @@ func (s *seleniumGridScaler) Close(context.Context) error {
 }
 
 func (s *seleniumGridScaler) GetMetricsAndActivity(ctx context.Context, metricName string) ([]external_metrics.ExternalMetricValue, bool, error) {
-	sessions, err := s.getSessionsCount(ctx, s.logger)
+	queueLen, err := s.getSessionsQueueLength(ctx, s.logger)
 	if err != nil {
 		return []external_metrics.ExternalMetricValue{}, false, fmt.Errorf("error requesting selenium grid endpoint: %w", err)
 	}
 
-	metric := GenerateMetricInMili(metricName, float64(sessions))
+	metric := GenerateMetricInMili(metricName, float64(queueLen))
 
-	return []external_metrics.ExternalMetricValue{metric}, sessions > s.metadata.ActivationThreshold, nil
+	// If the number of sessions queued is equal to or greater than the targetQueueLength, the scaler will scale up.
+	return []external_metrics.ExternalMetricValue{metric}, queueLen >= s.metadata.TargetQueueLength, nil
 }
 
 func (s *seleniumGridScaler) GetMetricSpecForScaling(context.Context) []v2.MetricSpec {
-	metricName := kedautil.NormalizeString(fmt.Sprintf("seleniumgrid-%s", s.metadata.BrowserName))
+	metricName := kedautil.NormalizeString(fmt.Sprintf("selenium-grid-%s-%s-%s", s.metadata.BrowserName, s.metadata.BrowserVersion, s.metadata.PlatformName))
 	externalMetric := &v2.ExternalMetricSource{
 		Metric: v2.MetricIdentifier{
 			Name: GenerateMetricNameWithIndex(s.metadata.triggerIndex, metricName),
 		},
-		Target: GetMetricTarget(s.metricType, s.metadata.TargetValue),
+		Target: GetMetricTarget(s.metricType, s.metadata.TargetQueueLength),
 	}
 	metricSpec := v2.MetricSpec{
 		External: externalMetric, Type: externalMetricType,
 	}
 	return []v2.MetricSpec{metricSpec}
 }
 
-func (s *seleniumGridScaler) getSessionsCount(ctx context.Context, logger logr.Logger) (int64, error) {
+func (s *seleniumGridScaler) getSessionsQueueLength(ctx context.Context, logger logr.Logger) (int64, error) {
 	body, err := json.Marshal(map[string]string{
 		"query": "{ grid { sessionCount, maxSession, totalSlots }, nodesInfo { nodes { id, status, sessionCount, maxSession, slotCount, stereotypes, sessions { id, capabilities, slot { id, stereotype } } } }, sessionsInfo { sessionQueueRequests } }",
 	})

diff --git a/pkg/scalers/selenium_grid_scaler_test.go b/pkg/scalers/selenium_grid_scaler_test.go
@@ -1750,7 +1750,7 @@ func Test_parseSeleniumGridScalerMetadata(t *testing.T) {
 				URL:                "http://selenium-hub:4444/graphql",
 				BrowserName:        "chrome",
 				SessionBrowserName: "chrome",
-				TargetValue:        1,
+				TargetQueueLength:  1,
 				BrowserVersion:     "latest",
 				PlatformName:       "linux",
 				NodeMaxSessions:    1,
@@ -1772,7 +1772,7 @@ func Test_parseSeleniumGridScalerMetadata(t *testing.T) {
 				URL:                "http://selenium-hub:4444/graphql",
 				BrowserName:        "MicrosoftEdge",
 				SessionBrowserName: "msedge",
-				TargetValue:        1,
+				TargetQueueLength:  1,
 				BrowserVersion:     "latest",
 				PlatformName:       "linux",
 				NodeMaxSessions:    1,
@@ -1800,7 +1800,7 @@ func Test_parseSeleniumGridScalerMetadata(t *testing.T) {
 				Password:           "password",
 				BrowserName:        "MicrosoftEdge",
 				SessionBrowserName: "msedge",
-				TargetValue:        1,
+				TargetQueueLength:  1,
 				BrowserVersion:     "latest",
 				PlatformName:       "linux",
 				NodeMaxSessions:    1,
@@ -1826,7 +1826,7 @@ func Test_parseSeleniumGridScalerMetadata(t *testing.T) {
 				URL:                "http://selenium-hub:4444/graphql",
 				BrowserName:        "MicrosoftEdge",
 				SessionBrowserName: "msedge",
-				TargetValue:        1,
+				TargetQueueLength:  1,
 				BrowserVersion:     "latest",
 				PlatformName:       "linux",
 				Username:           "username",
@@ -1851,7 +1851,7 @@ func Test_parseSeleniumGridScalerMetadata(t *testing.T) {
 				URL:                "http://selenium-hub:4444/graphql",
 				BrowserName:        "chrome",
 				SessionBrowserName: "chrome",
-				TargetValue:        1,
+				TargetQueueLength:  1,
 				BrowserVersion:     "91.0",
 				UnsafeSsl:          false,
 				PlatformName:       "linux",
@@ -1876,7 +1876,7 @@ func Test_parseSeleniumGridScalerMetadata(t *testing.T) {
 				URL:                 "http://selenium-hub:4444/graphql",
 				BrowserName:         "chrome",
 				SessionBrowserName:  "chrome",
-				TargetValue:         1,
+				TargetQueueLength:   1,
 				ActivationThreshold: 10,
 				BrowserVersion:      "91.0",
 				UnsafeSsl:           true,
@@ -1917,7 +1917,7 @@ func Test_parseSeleniumGridScalerMetadata(t *testing.T) {
 				URL:                 "http://selenium-hub:4444/graphql",
 				BrowserName:         "chrome",
 				SessionBrowserName:  "chrome",
-				TargetValue:         1,
+				TargetQueueLength:   1,
 				ActivationThreshold: 10,
 				BrowserVersion:      "91.0",
 				UnsafeSsl:           true,
@@ -1944,7 +1944,7 @@ func Test_parseSeleniumGridScalerMetadata(t *testing.T) {
 				URL:                 "http://selenium-hub:4444/graphql",
 				BrowserName:         "chrome",
 				SessionBrowserName:  "chrome",
-				TargetValue:         1,
+				TargetQueueLength:   1,
 				ActivationThreshold: 10,
 				BrowserVersion:      "91.0",
 				UnsafeSsl:           true,
@@ -1978,7 +1978,7 @@ func Test_parseSeleniumGridScalerMetadata(t *testing.T) {
 				Password:            "password",
 				BrowserName:         "chrome",
 				SessionBrowserName:  "chrome",
-				TargetValue:         1,
+				TargetQueueLength:   1,
 				ActivationThreshold: 10,
 				BrowserVersion:      "91.0",
 				UnsafeSsl:           true,
@@ -2013,7 +2013,7 @@ func Test_parseSeleniumGridScalerMetadata(t *testing.T) {
 				Password:            "password",
 				BrowserName:         "chrome",
 				SessionBrowserName:  "chrome",
-				TargetValue:         1,
+				TargetQueueLength:   1,
 				ActivationThreshold: 10,
 				BrowserVersion:      "91.0",
 				UnsafeSsl:           true,
@@ -2048,7 +2048,7 @@ func Test_parseSeleniumGridScalerMetadata(t *testing.T) {
 				AccessToken:         "my-access-token",
 				BrowserName:         "chrome",
 				SessionBrowserName:  "chrome",
-				TargetValue:         1,
+				TargetQueueLength:   1,
 				ActivationThreshold: 10,
 				BrowserVersion:      "91.0",
 				UnsafeSsl:           true,
@@ -2082,7 +2082,7 @@ func Test_parseSeleniumGridScalerMetadata(t *testing.T) {
 				AccessToken:         "my-access-token",
 				BrowserName:         "chrome",
 				SessionBrowserName:  "chrome",
-				TargetValue:         1,
+				TargetQueueLength:   1,
 				ActivationThreshold: 10,
 				BrowserVersion:      "91.0",
 				UnsafeSsl:           true,