Add e2e tests for autoscaling

Author: nikParasyr

test/e2e/data/e2e_conf.yaml

@@ -213,6 +213,7 @@ variables:
   KUBERNETES_VERSION: "v1.34.2"
   KUBERNETES_VERSION_UPGRADE_FROM: "v1.33.1"
   KUBERNETES_VERSION_UPGRADE_TO: "v1.34.2"
+  AUTOSCALER_VERSION: "v1.34.2"
   # NOTE: To see default images run kubeadm config images list (optionally with --kubernetes-version=vX.Y.Z)
   ETCD_VERSION_UPGRADE_TO: "3.5.21-0"
   COREDNS_VERSION_UPGRADE_TO: "v1.12.0"
@@ -222,6 +223,7 @@ variables:
   CCM: "../../data/ccm/cloud-controller-manager.yaml"
   EXP_CLUSTER_RESOURCE_SET: "true"
   EXP_CAPO_PRIORITY_QUEUE: "false"
+  EXP_CAPO_AUTOSCALE_FROM_ZERO: "true"
   IP_FAMILY: "ipv4"
   OPENSTACK_BASTION_IMAGE_NAME: "cirros-0.6.1-x86_64-disk"
   OPENSTACK_BASTION_IMAGE_URL: https://storage.googleapis.com/artifacts.k8s-staging-capi-openstack.appspot.com/test/cirros/2022-12-05/cirros-0.6.1-x86_64-disk.img

test/e2e/suites/e2e/autoscaler_test.go

@@ -0,0 +1,59 @@
+//go:build e2e
+
+/*
+Copyright 2025 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package e2e
+
+import (
+	"context"
+
+	. "github.com/onsi/ginkgo/v2"
+	capi_e2e "sigs.k8s.io/cluster-api/test/e2e"
+	"sigs.k8s.io/cluster-api/test/framework/clusterctl"
+
+	infrav1 "sigs.k8s.io/cluster-api-provider-openstack/api/v1beta1"
+	"sigs.k8s.io/cluster-api-provider-openstack/test/e2e/shared"
+)
+
+var _ = Describe("Autoscaler on ClusterClass cluster [Autoscaler] [ClusterClass]", func() {
+	capi_e2e.AutoscalerSpec(context.TODO(), func() capi_e2e.AutoscalerSpecInput {
+		infraAPIGroup := infrav1.GroupName
+		autoscalerFlavor := shared.FlavorTopology
+
+		return capi_e2e.AutoscalerSpecInput{
+			E2EConfig:             e2eCtx.E2EConfig,
+			ClusterctlConfigPath:  e2eCtx.Environment.ClusterctlConfigPath,
+			BootstrapClusterProxy: e2eCtx.Environment.BootstrapClusterProxy,
+			ArtifactFolder:        e2eCtx.Settings.ArtifactFolder,
+			SkipCleanup:           false,
+			ControlPlaneWaiters: clusterctl.ControlPlaneWaiters{
+				WaitForControlPlaneInitialized: e2eCtx.E2EConfig.GetIntervals("default", "wait-control-plane"),
+				WaitForControlPlaneReady:       e2eCtx.E2EConfig.GetIntervals("default", "wait-control-plane"),
+			},
+			Flavor:                            &autoscalerFlavor,
+			InfrastructureMachineTemplateKind: "openstackmachinetemplates",
+			// CAPO does not support machinePools
+			InfrastructureMachinePoolTemplateKind: "",
+			InfrastructureMachinePoolKind:         "",
+			InfrastructureAPIGroup:                infraAPIGroup,
+			AutoscalerVersion:                     e2eCtx.E2EConfig.MustGetVariable("AUTOSCALER_VERSION"),
+			InstallOnManagementCluster:            false,
+			ScaleToAndFromZero:                    true,
+			PostNamespaceCreated:                  nil,
+		}
+	})
+})