Install GH into a brownfield

Signed-off-by: clyang82 <[email protected]>

Author: clyang82

operator/api/operator/v1alpha4/multiclusterglobalhub_types.go

@@ -107,6 +107,13 @@ type MulticlusterGlobalHubSpec struct {
 	// +operator-sdk:csv:customresourcedefinitions:type=spec,xDescriptors={"urn:alm:descriptor:com.tectonic.ui:booleanSwitch"}
 	// +optional
 	EnableMetrics bool `json:"enableMetrics"`
+	// InstallAgentOnHub determines whether deploy the Global Hub Agent on hub cluster.
+	// If set to true, the Global Hub Agent will be installed on the hub cluster only.
+	// If set to false, the Global Hub Agent will not be installed on the hub cluster.
+	// Currently, switching the value of this field is not supported after the Global Hub is installed.
+	// +kubebuilder:default=false
+	// +optional
+	InstallAgentOnHub bool `json:"installAgentOnHub,omitempty"`
 }
 
 type AdvancedSpec struct {

operator/bundle/manifests/operator.open-cluster-management.io_multiclusterglobalhubs.yaml

@@ -248,6 +248,14 @@ spec:
                 description: ImagePullSecret specifies the pull secret of the multicluster
                   global hub images
                 type: string
+              installAgentOnHub:
+                default: false
+                description: |-
+                  InstallAgentOnHub determines whether deploy the Global Hub Agent on hub cluster.
+                  If set to true, the Global Hub Agent will be installed on the hub cluster only.
+                  If set to false, the Global Hub Agent will not be installed on the hub cluster.
+                  Currently, switching the value of this field is not supported after the Global Hub is installed.
+                type: boolean
               nodeSelector:
                 additionalProperties:
                   type: string

operator/config/crd/bases/operator.open-cluster-management.io_multiclusterglobalhubs.yaml

@@ -248,6 +248,14 @@ spec:
                 description: ImagePullSecret specifies the pull secret of the multicluster
                   global hub images
                 type: string
+              installAgentOnHub:
+                default: false
+                description: |-
+                  InstallAgentOnHub determines whether deploy the Global Hub Agent on hub cluster.
+                  If set to true, the Global Hub Agent will be installed on the hub cluster only.
+                  If set to false, the Global Hub Agent will not be installed on the hub cluster.
+                  Currently, switching the value of this field is not supported after the Global Hub is installed.
+                type: boolean
               nodeSelector:
                 additionalProperties:
                   type: string

operator/pkg/controllers/agent/default_agent_controller.go

@@ -261,7 +261,23 @@ func (r *DefaultAgentController) Reconcile(ctx context.Context, req ctrl.Request
 		return ctrl.Result{}, nil
 	}
 
-	return ctrl.Result{}, r.reconcileAddonAndResources(ctx, cluster, clusterManagementAddOn)
+	if mgh.Spec.InstallAgentOnHub {
+		// if installed agent on hub cluster, global hub is installed in a brownfield cluster
+		if cluster.GetName() == constants.LocalClusterName ||
+			cluster.Labels[constants.LocalClusterName] == "true" ||
+			deployMode != operatorconstants.GHAgentDeployModeNone {
+			return ctrl.Result{}, r.reconcileAddonAndResources(ctx, cluster, clusterManagementAddOn)
+		}
+	} else {
+		// if not installed agent on hub cluster, global hub is installed in a greenfield cluster
+		if cluster.GetName() == constants.LocalClusterName ||
+			cluster.Labels[constants.LocalClusterName] == "true" {
+			return ctrl.Result{}, nil
+		}
+		return ctrl.Result{}, r.reconcileAddonAndResources(ctx, cluster, clusterManagementAddOn)
+	}
+
+	return ctrl.Result{}, nil
 }
 
 func (r *DefaultAgentController) deleteClusterManagementAddon(ctx context.Context) error {
@@ -457,6 +473,5 @@ func GetAllManagedHubNames(ctx context.Context, c client.Client) ([]string, erro
 
 func filterManagedCluster(obj client.Object) bool {
 	return obj.GetLabels()["vendor"] != "OpenShift" ||
-		obj.GetLabels()["openshiftVersion"] == "3" ||
-		obj.GetName() == constants.LocalClusterName
+		obj.GetLabels()["openshiftVersion"] == "3"
 }