azure: Create resource group during PreProvision

Creating a resource group in PreProvision stage of CAPZ to
enable users to set the ManagedBy field.

pkg/infrastructure/azure/azure.go

@@ -1,6 +1,14 @@
 package azure
 
 import (
+	"context"
+	"fmt"
+
+	"github.com/Azure/azure-sdk-for-go/sdk/azidentity"
+	"github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/resources/armresources"
+	"github.com/Azure/go-autorest/autorest/to"
+
+	"github.com/openshift/installer/pkg/asset/installconfig"
 	"github.com/openshift/installer/pkg/infrastructure/clusterapi"
 	azuretypes "github.com/openshift/installer/pkg/types/azure"
 )
@@ -12,3 +20,34 @@ type Provider struct{}
 
 // Name gives the name of the provider, Azure.
 func (*Provider) Name() string { return azuretypes.Name }
+
+func (*Provider) PreProvision(ctx context.Context, in clusterapi.PreProvisionInput) {
+	if in.InstallConfig.Config.Azure.ResourceGroupName == "" {
+		createResourceGroup(ctx, in.InstallConfig, in.InfraID)
+	}
+}
+
+// createResourceGroup creates the resource group required for Azure installation.
+func createResourceGroup(ctx context.Context, ic *installconfig.InstallConfig, infraID string) error {
+	rgName := fmt.Sprintf("%s-rg", infraID)
+	managedBy := ic.Config.Azure.ManagedBy
+	session, err := ic.Azure.Session()
+	if err != nil {
+		return err
+	}
+	cred, err := azidentity.NewDefaultAzureCredential(nil)
+	if err != nil {
+		return err
+	}
+	rgClient, err := armresources.NewResourceGroupsClient(session.Credentials.SubscriptionID, cred, nil)
+	if err != nil {
+		return err
+	}
+	param := armresources.ResourceGroup{
+		Location:  to.StringPtr(ic.Config.Azure.Region),
+		ManagedBy: &managedBy,
+	}
+
+	_, err = rgClient.CreateOrUpdate(ctx, rgName, param, nil)
+	return err
+}