Let operator manage autoscaling of node groups

operators/constellation-node-operator/internal/gcp/client/autocaler.go

@@ -0,0 +1,12 @@
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+package client
+
+// AutoscalingCloudProvider returns the cloud-provider name as used by k8s cluster-autoscaler.
+func (c *Client) AutoscalingCloudProvider() string {
+	return "gce"
+}

operators/constellation-node-operator/internal/gcp/client/disks.go

@@ -40,3 +40,12 @@ func uriNormalize(imageURI string) string {
 	}
 	return matches[1]
 }
+
+// ensureURIPrefixed ensures that a compute API URI is prefixed with the optional URI prefix.
+func ensureURIPrefixed(uri string) string {
+	matches := computeAPIBase.FindStringSubmatch(uri)
+	if len(matches) == 2 {
+		return uri
+	}
+	return "https://www.googleapis.com/compute/v1/" + uri
+}

operators/constellation-node-operator/internal/gcp/client/scalinggroup.go

@@ -10,7 +10,6 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"strings"
 
 	"google.golang.org/api/iterator"
 	computepb "google.golang.org/genproto/googleapis/cloud/compute/v1"
@@ -87,12 +86,23 @@ func (c *Client) SetScalingGroupImage(ctx context.Context, scalingGroupID, image
 }
 
 // GetScalingGroupName retrieves the name of a scaling group.
-func (c *Client) GetScalingGroupName(ctx context.Context, scalingGroupID string) (string, error) {
+// This keeps the casing of the original name, but Kubernetes requires the name to be lowercase,
+// so use strings.ToLower() on the result if using the name in a Kubernetes context.
+func (c *Client) GetScalingGroupName(scalingGroupID string) (string, error) {
 	_, _, instanceGroupName, err := splitInstanceGroupID(scalingGroupID)
 	if err != nil {
 		return "", fmt.Errorf("getting scaling group name: %w", err)
 	}
-	return strings.ToLower(instanceGroupName), nil
+	return instanceGroupName, nil
+}
+
+// GetScalingGroupName retrieves the name of a scaling group as needed by the cluster-autoscaler.
+func (c *Client) GetAutoscalingGroupName(scalingGroupID string) (string, error) {
+	project, zone, instanceGroupName, err := splitInstanceGroupID(scalingGroupID)
+	if err != nil {
+		return "", fmt.Errorf("getting autoscaling scaling group name: %w", err)
+	}
+	return ensureURIPrefixed(fmt.Sprintf("projects/%s/zones/%s/instanceGroups/%s", project, zone, instanceGroupName)), nil
 }
 
 // ListScalingGroups retrieves a list of scaling groups for the cluster.

operators/constellation-node-operator/internal/gcp/client/scalinggroup_test.go

@@ -311,7 +311,7 @@ func TestGetScalingGroupName(t *testing.T) {
 			require := require.New(t)
 
 			client := Client{}
-			gotName, err := client.GetScalingGroupName(context.Background(), tc.scalingGroupID)
+			gotName, err := client.GetScalingGroupName(tc.scalingGroupID)
 			if tc.wantErr {
 				assert.Error(err)
 				return