feat(cluster-autoscaler): improve nodes listing in ClusterAPI provider

Add improved error handling for machines phase in the ClusterAPI node group
implementation. When a machine is in Deleting/Failed/Pending phase, mark the cloudprovider.Instance
with a status for cluster-autoscaler recovery actions.

The changes:
- Enhance Nodes listing to allow reporting the machine phase in Instance status
- Add error status reporting for failed machines

This change helps identify and manage failed machines more effectively,
allowing the autoscaler to make better scaling decisions.

Author: loick111

cluster-autoscaler/cloudprovider/clusterapi/clusterapi_nodegroup.go

@@ -253,9 +253,82 @@ func (ng *nodegroup) Nodes() ([]cloudprovider.Instance, error) {
 	// must match the ID on the Node object itself.
 	// https://github.com/kubernetes/autoscaler/blob/a973259f1852303ba38a3a61eeee8489cf4e1b13/cluster-autoscaler/clusterstate/clusterstate.go#L967-L985
 	instances := make([]cloudprovider.Instance, len(providerIDs))
-	for i := range providerIDs {
+	for i, providerID := range providerIDs {
+		providerIDNormalized := normalizedProviderID(providerID)
+
+		// Add instance Status to report instance state to cluster-autoscaler.
+		// This helps cluster-autoscaler make better scaling decisions.
+		//
+		// Machine can be Failed for a variety of reasons, here we are looking for a specific errors:
+		// - Failed to provision
+		// - Failed to delete.
+		// Other reasons for a machine to be in a Failed state are not forwarding Status to the autoscaler.
+		var status *cloudprovider.InstanceStatus
+		switch {
+		case isFailedMachineProviderID(providerIDNormalized):
+			klog.V(4).Infof("Machine failed in node group %s (%s)", ng.Id(), providerID)
+
+			machine, err := ng.machineController.findMachineByProviderID(providerIDNormalized)
+			if err != nil {
+				return nil, err
+			}
+
+			if machine != nil {
+				if !machine.GetDeletionTimestamp().IsZero() {
+					klog.V(4).Infof("Machine failed in node group %s (%s) is being deleted", ng.Id(), providerID)
+					status = &cloudprovider.InstanceStatus{
+						State: cloudprovider.InstanceDeleting,
+						ErrorInfo: &cloudprovider.InstanceErrorInfo{
+							ErrorClass:   cloudprovider.OtherErrorClass,
+							ErrorCode:    "DeletingFailed",
+							ErrorMessage: "Machine deletion failed",
+						},
+					}
+				} else {
+					_, nodeFound, err := unstructured.NestedFieldCopy(machine.UnstructuredContent(), "status", "nodeRef")
+					if err != nil {
+						return nil, err
+					}
+
+					// Machine failed without a nodeRef, this indicates that the machine failed to provision.
+					// This is a special case where the machine is in a Failed state and the node is not created.
+					// Machine controller will not reconcile this machine, so we need to report this to the autoscaler.
+					if !nodeFound {
+						klog.V(4).Infof("Machine failed in node group %s (%s) was being created", ng.Id(), providerID)
+						status = &cloudprovider.InstanceStatus{
+							State: cloudprovider.InstanceCreating,
+							ErrorInfo: &cloudprovider.InstanceErrorInfo{
+								ErrorClass:   cloudprovider.OtherErrorClass,
+								ErrorCode:    "ProvisioningFailed",
+								ErrorMessage: "Machine provisioning failed",
+							},
+						}
+					}
+				}
+			}
+
+		case isPendingMachineProviderID(providerIDNormalized):
+			klog.V(4).Infof("Machine pending in node group %s (%s)", ng.Id(), providerID)
+			status = &cloudprovider.InstanceStatus{
+				State: cloudprovider.InstanceCreating,
+			}
+
+		case isDeletingMachineProviderID(providerIDNormalized):
+			klog.V(4).Infof("Machine deleting in node group %s (%s)", ng.Id(), providerID)
+			status = &cloudprovider.InstanceStatus{
+				State: cloudprovider.InstanceDeleting,
+			}
+
+		default:
+			klog.V(4).Infof("Machine running in node group %s (%s)", ng.Id(), providerID)
+			status = &cloudprovider.InstanceStatus{
+				State: cloudprovider.InstanceRunning,
+			}
+		}
+
 		instances[i] = cloudprovider.Instance{
-			Id: providerIDs[i],
+			Id:     providerID,
+			Status: status,
 		}
 	}
 

cluster-autoscaler/cloudprovider/clusterapi/clusterapi_nodegroup_test.go

@@ -1736,3 +1736,223 @@ func TestNodeGroupGetOptions(t *testing.T) {
 		})
 	}
 }
+
+func TestNodeGroupNodesInstancesStatus(t *testing.T) {
+	type testCase struct {
+		description                        string
+		nodeCount                          int
+		includePendingMachine              bool
+		includeDeletingMachine             bool
+		includeFailedMachineWithNodeRef    bool
+		includeFailedMachineWithoutNodeRef bool
+		includeFailedMachineDeleting       bool
+	}
+
+	testCases := []testCase{
+		{
+			description: "standard number of nodes",
+			nodeCount:   5,
+		},
+		{
+			description:           "includes a machine in pending state",
+			nodeCount:             5,
+			includePendingMachine: true,
+		},
+		{
+			description:            "includes a machine in deleting state",
+			nodeCount:              5,
+			includeDeletingMachine: true,
+		},
+		{
+			description:                     "includes a machine in failed state with nodeRef",
+			nodeCount:                       5,
+			includeFailedMachineWithNodeRef: true,
+		},
+		{
+			description:                        "includes a machine in failed state without nodeRef",
+			nodeCount:                          5,
+			includeFailedMachineWithoutNodeRef: true,
+		},
+	}
+
+	test := func(t *testing.T, tc *testCase, testConfig *testConfig) {
+		controller, stop := mustCreateTestController(t, testConfig)
+		defer stop()
+
+		if tc.includePendingMachine {
+			if tc.nodeCount < 1 {
+				t.Fatal("test cannot pass, deleted machine requires at least 1 machine in machineset")
+			}
+
+			machine := testConfig.machines[0].DeepCopy()
+			unstructured.RemoveNestedField(machine.Object, "spec", "providerID")
+			unstructured.RemoveNestedField(machine.Object, "status", "nodeRef")
+
+			if err := updateResource(controller.managementClient, controller.machineInformer, controller.machineResource, machine); err != nil {
+				t.Fatalf("unexpected error updating machine, got %v", err)
+			}
+		}
+
+		if tc.includeDeletingMachine {
+			if tc.nodeCount < 2 {
+				t.Fatal("test cannot pass, deleted machine requires at least 2 machine in machineset")
+			}
+
+			machine := testConfig.machines[1].DeepCopy()
+			timestamp := metav1.Now()
+			machine.SetDeletionTimestamp(&timestamp)
+
+			if err := updateResource(controller.managementClient, controller.machineInformer, controller.machineResource, machine); err != nil {
+				t.Fatalf("unexpected error updating machine, got %v", err)
+			}
+		}
+
+		if tc.includeFailedMachineWithNodeRef {
+			if tc.nodeCount < 3 {
+				t.Fatal("test cannot pass, deleted machine requires at least 3 machine in machineset")
+			}
+
+			machine := testConfig.machines[2].DeepCopy()
+			unstructured.SetNestedField(machine.Object, "node-1", "status", "nodeRef", "name")
+			unstructured.SetNestedField(machine.Object, "ErrorMessage", "status", "errorMessage")
+
+			if err := updateResource(controller.managementClient, controller.machineInformer, controller.machineResource, machine); err != nil {
+				t.Fatalf("unexpected error updating machine, got %v", err)
+			}
+		}
+
+		if tc.includeFailedMachineWithoutNodeRef {
+			if tc.nodeCount < 4 {
+				t.Fatal("test cannot pass, deleted machine requires at least 4 machine in machineset")
+			}
+
+			machine := testConfig.machines[3].DeepCopy()
+			unstructured.RemoveNestedField(machine.Object, "status", "nodeRef")
+			unstructured.SetNestedField(machine.Object, "ErrorMessage", "status", "errorMessage")
+
+			if err := updateResource(controller.managementClient, controller.machineInformer, controller.machineResource, machine); err != nil {
+				t.Fatalf("unexpected error updating machine, got %v", err)
+			}
+		}
+
+		if tc.includeFailedMachineDeleting {
+			if tc.nodeCount < 5 {
+				t.Fatal("test cannot pass, deleted machine requires at least 5 machine in machineset")
+			}
+
+			machine := testConfig.machines[4].DeepCopy()
+			timestamp := metav1.Now()
+			machine.SetDeletionTimestamp(&timestamp)
+			unstructured.SetNestedField(machine.Object, "ErrorMessage", "status", "errorMessage")
+
+			if err := updateResource(controller.managementClient, controller.machineInformer, controller.machineResource, machine); err != nil {
+				t.Fatalf("unexpected error updating machine, got %v", err)
+			}
+		}
+
+		nodegroups, err := controller.nodeGroups()
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+
+		if l := len(nodegroups); l != 1 {
+			t.Fatalf("expected 1 nodegroup, got %d", l)
+		}
+
+		ng := nodegroups[0]
+		instances, err := ng.Nodes()
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+
+		expectedCount := tc.nodeCount
+		if len(instances) != expectedCount {
+			t.Errorf("expected %d nodes, got %d", expectedCount, len(instances))
+		}
+
+		// Sort instances by Id for stable comparison
+		sort.Slice(instances, func(i, j int) bool {
+			return instances[i].Id < instances[j].Id
+		})
+
+		for _, instance := range instances {
+			t.Logf("instance: %v", instance)
+			if tc.includePendingMachine && strings.HasPrefix(instance.Id, pendingMachinePrefix) {
+				if instance.Status == nil || instance.Status.State != cloudprovider.InstanceCreating {
+					t.Errorf("expected pending machine to have status %v, got %v", cloudprovider.InstanceCreating, instance.Status)
+				}
+			} else if tc.includeDeletingMachine && strings.HasPrefix(instance.Id, deletingMachinePrefix) {
+				if instance.Status == nil || instance.Status.State != cloudprovider.InstanceDeleting {
+					t.Errorf("expected deleting machine to have status %v, got %v", cloudprovider.InstanceDeleting, instance.Status)
+				}
+			} else if tc.includeFailedMachineWithNodeRef && strings.HasPrefix(instance.Id, failedMachinePrefix) {
+				if instance.Status != nil {
+					t.Errorf("expected failed machine with nodeRef to not have status, got %v", instance.Status)
+				}
+			} else if tc.includeFailedMachineWithoutNodeRef && strings.HasPrefix(instance.Id, failedMachinePrefix) {
+				if instance.Status == nil || instance.Status.State != cloudprovider.InstanceCreating {
+					t.Errorf("expected failed machine without nodeRef to have status %v, got %v", cloudprovider.InstanceCreating, instance.Status)
+				}
+				if instance.Status == nil || instance.Status.ErrorInfo.ErrorClass != cloudprovider.OtherErrorClass {
+					t.Errorf("expected failed machine without nodeRef to have error class %v, got %v", cloudprovider.OtherErrorClass, instance.Status.ErrorInfo.ErrorClass)
+				}
+				if instance.Status == nil || instance.Status.ErrorInfo.ErrorCode != "ProvisioningFailed" {
+					t.Errorf("expected failed machine without nodeRef to have error code %v, got %v", "ProvisioningFailed", instance.Status.ErrorInfo.ErrorCode)
+				}
+			} else if tc.includeFailedMachineDeleting && strings.HasPrefix(instance.Id, failedMachinePrefix) {
+				if instance.Status == nil || instance.Status.State != cloudprovider.InstanceDeleting {
+					t.Errorf("expected failed machine deleting to have status %v, got %v", cloudprovider.InstanceDeleting, instance.Status)
+				}
+				if instance.Status == nil || instance.Status.ErrorInfo.ErrorClass != cloudprovider.OtherErrorClass {
+					t.Errorf("expected failed machine deleting to have error class %v, got %v", cloudprovider.OtherErrorClass, instance.Status.ErrorInfo.ErrorClass)
+				}
+				if instance.Status == nil || instance.Status.ErrorInfo.ErrorCode != "DeletingFailed" {
+					t.Errorf("expected failed machine deleting to have error code %v, got %v", "DeletingFailed", instance.Status.ErrorInfo.ErrorCode)
+				}
+			}
+		}
+	}
+
+	annotations := map[string]string{
+		nodeGroupMinSizeAnnotationKey: "1",
+		nodeGroupMaxSizeAnnotationKey: "10",
+	}
+
+	t.Run("MachineSet", func(t *testing.T) {
+		for _, tc := range testCases {
+			t.Run(tc.description, func(t *testing.T) {
+				test(
+					t,
+					&tc,
+					createMachineSetTestConfig(
+						RandomString(6),
+						RandomString(6),
+						RandomString(6),
+						tc.nodeCount,
+						annotations,
+						nil,
+					),
+				)
+			})
+		}
+	})
+
+	t.Run("MachineDeployment", func(t *testing.T) {
+		for _, tc := range testCases {
+			t.Run(tc.description, func(t *testing.T) {
+				test(
+					t,
+					&tc,
+					createMachineDeploymentTestConfig(
+						RandomString(6),
+						RandomString(6),
+						RandomString(6),
+						tc.nodeCount,
+						annotations,
+						nil,
+					),
+				)
+			})
+		}
+	})
+}