fix/datadog-scaler-null-last-point

CHANGELOG.md

@@ -79,6 +79,7 @@ To learn more about active deprecations, we recommend checking [GitHub Discussio
 - **New Relic Scaler** Store forgotten logger ([#3945](https://github.com/kedacore/keda/issues/3945))
 - **Prometheus Scaler:** Treat Inf the same as Null result ([#3644](https://github.com/kedacore/keda/issues/3644))
 - **NATS Jetstream:** Correctly count messages that should be redelivered (waiting for ack) towards keda value ([#3787](https://github.com/kedacore/keda/issues/3787))
+- **Datadog Scaler** The last data point of some specific query is always null ([#3906](https://github.com/kedacore/keda/issues/3906))
 
 ### Deprecations
 

pkg/scalers/datadog_scaler.go

@@ -304,6 +304,13 @@ func (s *datadogScaler) getQueryResult(ctx context.Context) (float64, error) {
 	for i := 0; i < len(series); i++ {
 		points := series[i].GetPointlist()
 		index := len(points) - 1
+		// Find out the last point != nil
+		for i := len(points) - 1; i >= 0; i-- {
+			if len(points[index]) >= 2 && points[i][1] != nil {
+				index = i
+				break
+			}
+		}
 		if len(points) == 0 || len(points[index]) < 2 || points[index][1] == nil {
 			if !s.metadata.useFiller {
 				return 0, fmt.Errorf("no Datadog metrics returned for the given time window")