OverrideLabels hook for operand pod labels

Signed-off-by: Swarup Ghosh <swghosh@redhat.com>

pkg/controller/deployment/deployment_helper.go

@@ -76,6 +76,17 @@ func parseArgMap(argMap map[string]string, args []string) {
 	}
 }
 
+func mergeLabels(sourceLabels map[string]string, overrideLabels map[string]string) map[string]string {
+	destLabels := map[string]string{}
+	for k, v := range sourceLabels {
+		destLabels[k] = v
+	}
+	for k, v := range overrideLabels {
+		destLabels[k] = v
+	}
+	return destLabels
+}
+
 // getOverrideArgsFor is a helper function that returns the overrideArgs provided
 // in the operator spec based on the deployment name.
 func getOverrideArgsFor(certmanagerinformer certmanagerinformer.CertManagerInformer, deploymentName string) ([]string, error) {
@@ -129,3 +140,31 @@ func getOverrideEnvFor(certmanagerinformer certmanagerinformer.CertManagerInform
 	}
 	return nil, nil
 }
+
+// getOverridePodLabelsFor() is a helper function that returns the OverridePodLabels provided
+// in the operator spec based on the deployment name.
+func getOverridePodLabelsFor(certmanagerinformer certmanagerinformer.CertManagerInformer, deploymentName string) (map[string]string, error) {
+	certmanager, err := certmanagerinformer.Lister().Get("cluster")
+	if err != nil {
+		return nil, fmt.Errorf("failed to get certmanager %q due to %v", "cluster", err)
+	}
+
+	switch deploymentName {
+	case certmanagerControllerDeployment:
+		if certmanager.Spec.ControllerConfig != nil {
+			return certmanager.Spec.ControllerConfig.OverrideLabels, nil
+		}
+	case certmanagerWebhookDeployment:
+		if certmanager.Spec.WebhookConfig != nil {
+			return certmanager.Spec.WebhookConfig.OverrideLabels, nil
+		}
+	case certmanagerCAinjectorDeployment:
+		if certmanager.Spec.CAInjectorConfig != nil {
+			return certmanager.Spec.CAInjectorConfig.OverrideLabels, nil
+		}
+	default:
+		return nil, fmt.Errorf("unsupported deployment name %q provided", deploymentName)
+	}
+	return nil, nil
+
+}

pkg/controller/deployment/deployment_overrides.go

@@ -37,6 +37,11 @@ type overrideArgsFunc func(certmanagerinformer.CertManagerInformer, string) ([]s
 // override env provided to the cert-manager-operator operator spec.
 type overrideEnvFunc func(certmanagerinformer.CertManagerInformer, string) ([]corev1.EnvVar, error)
 
+// overrideLabelsFunc defines a function signature that is accepted by
+// withPodLabels(). This function returns the override labels provided
+// to cert-manager-operator spec.
+type overrideLabelsFunc func(certmanagerinformer.CertManagerInformer, string) (map[string]string, error)
+
 // withOperandImageOverrideHook overrides the deployment image with
 // the operand images provided to the operator.
 func withOperandImageOverrideHook(operatorSpec *v1.OperatorSpec, deployment *appsv1.Deployment) error {
@@ -127,3 +132,18 @@ func withCAConfigMap(configmapinformer coreinformersv1.ConfigMapInformer, deploy
 		return nil
 	}
 }
+
+// withPodLabels patches the operand deployment to include custom pod labels
+func withPodLabelsOverrideHook(certmanagerinformer certmanagerinformer.CertManagerInformer, deploymentName string, fn overrideLabelsFunc) func(operatorSpec *v1.OperatorSpec, deployment *appsv1.Deployment) error {
+	return func(operatorSpec *v1.OperatorSpec, deployment *appsv1.Deployment) error {
+		overrideLabels, err := fn(certmanagerinformer, deploymentName)
+		if err != nil {
+			return err
+		}
+
+		if overrideLabels != nil && len(overrideLabels) > 0 && len(deployment.Spec.Template.ObjectMeta.Labels) == 1 && deployment.Name == deploymentName {
+			deployment.Spec.Template.SetLabels(mergeLabels(deployment.Spec.Template.ObjectMeta.Labels, overrideLabels))
+		}
+		return nil
+	}
+}

pkg/controller/deployment/generic_deployment_controller.go

@@ -38,6 +38,7 @@ func newGenericDeploymentController(
 		},
 		[]deploymentcontroller.ManifestHookFunc{},
 		withOperandImageOverrideHook,
+		withPodLabelsOverrideHook(certManagerOperatorInformers.Operator().V1alpha1().CertManagers(), deployment.Name, getOverridePodLabelsFor),
 		withContainerArgsOverrideHook(certManagerOperatorInformers.Operator().V1alpha1().CertManagers(), deployment.Name, getOverrideArgsFor),
 		withContainerArgsValidateHook(certManagerOperatorInformers.Operator().V1alpha1().CertManagers(), deployment.Name),
 		withContainerEnvOverrideHook(certManagerOperatorInformers.Operator().V1alpha1().CertManagers(), deployment.Name, getOverrideEnvFor),