Fix node spec podLabels bug

The operator does not add node spec's podLabels to the statefulsets
unless a user also defines podLabels for the cluster spec.

This change will always add both cluster and node spec podLabels as long
as they are defined. If same labels are defined for both cluster spec and
pod spec then it'll prefer node spec values over cluster spec.

controllers/druid/handler.go

@@ -1268,17 +1268,16 @@ func makeLabelsForDruid(druid *v1alpha1.Druid) map[string]string {
 }
 
 // makeLabelsForDruid returns the labels for selecting the resources
-// belonging to the given druid CR name.
+// belonging to the given druid CR name. adds labels from both node &
+// cluster specs. node spec labels will take precedence over clusters labels
 func makeLabelsForNodeSpec(nodeSpec *v1alpha1.DruidNodeSpec, m *v1alpha1.Druid, clusterName, nodeSpecUniqueStr string) map[string]string {
 	var labels = map[string]string{}
 
-	// if both labels are present at both cluster and node spec
-	// labels should be merged.
-	if nodeSpec.PodLabels != nil && m.Spec.PodLabels != nil {
-		labels = nodeSpec.PodLabels
+	for k, v := range m.Spec.PodLabels {
+		labels[k] = v
 	}
 
-	for k, v := range m.Spec.PodLabels {
+	for k, v := range nodeSpec.PodLabels {
 		labels[k] = v
 	}