maasmachine_controller.go

/*


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 controllers

import (
	"context"
	"encoding/base64"
	"fmt"
	"k8s.io/apimachinery/pkg/runtime"
	"time"

	"github.com/go-logr/logr"
	"github.com/pkg/errors"
	corev1 "k8s.io/api/core/v1"
	apierrors "k8s.io/apimachinery/pkg/api/errors"
	"k8s.io/client-go/tools/record"
	clusterv1 "sigs.k8s.io/cluster-api/api/v1beta1"
	"sigs.k8s.io/cluster-api/controllers/remote"
	capierrors "sigs.k8s.io/cluster-api/errors"
	"sigs.k8s.io/cluster-api/util"
	"sigs.k8s.io/cluster-api/util/annotations"
	"sigs.k8s.io/cluster-api/util/conditions"
	"sigs.k8s.io/cluster-api/util/predicates"
	ctrl "sigs.k8s.io/controller-runtime"
	"sigs.k8s.io/controller-runtime/pkg/client"
	"sigs.k8s.io/controller-runtime/pkg/controller"
	"sigs.k8s.io/controller-runtime/pkg/controller/controllerutil"
	"sigs.k8s.io/controller-runtime/pkg/handler"
	"sigs.k8s.io/controller-runtime/pkg/reconcile"
	"sigs.k8s.io/controller-runtime/pkg/source"

	//infrav1alpha3 "github.com/spectrocloud/cluster-api-provider-maas/api/v1alpha3"
	infrav1beta1 "github.com/spectrocloud/cluster-api-provider-maas/api/v1beta1"
	maasdns "github.com/spectrocloud/cluster-api-provider-maas/pkg/maas/dns"
	maasmachine "github.com/spectrocloud/cluster-api-provider-maas/pkg/maas/machine"
	"github.com/spectrocloud/cluster-api-provider-maas/pkg/maas/scope"
)

var ErrRequeueDNS = errors.New("need to requeue DNS")

// MaasMachineReconciler reconciles a MaasMachine object
type MaasMachineReconciler struct {
	client.Client
	Log      logr.Logger
	Scheme   *runtime.Scheme
	Recorder record.EventRecorder
	Tracker  *remote.ClusterCacheTracker
}

//+kubebuilder:rbac:groups=infrastructure.cluster.x-k8s.io,resources=maasmachines,verbs=get;list;watch;create;update;patch;delete
//+kubebuilder:rbac:groups=infrastructure.cluster.x-k8s.io,resources=maasmachines/status,verbs=get;update;patch
// +kubebuilder:rbac:groups=cluster.x-k8s.io,resources=clusters;machines,verbs=get;list;watch
// +kubebuilder:rbac:groups="",resources=secrets,verbs=get;list;watch
// +kubebuilder:rbac:groups="",resources=events,verbs=get;list;watch;create;update;patch

func (r *MaasMachineReconciler) Reconcile(ctx context.Context, req ctrl.Request) (_ ctrl.Result, rerr error) {
	log := r.Log.WithValues("maasmachine", req.Name)

	// Fetch the MaasMachine instance.
	maasMachine := &infrav1beta1.MaasMachine{}
	err := r.Get(ctx, req.NamespacedName, maasMachine)
	if err != nil {
		if apierrors.IsNotFound(err) {
			return ctrl.Result{}, nil
		}
		return ctrl.Result{}, err
	}

	// Fetch the Machine.
	machine, err := util.GetOwnerMachine(ctx, r.Client, maasMachine.ObjectMeta)
	if err != nil {
		return ctrl.Result{}, err
	}
	if machine == nil {
		log.Info("Machine Controller has not yet set OwnerRef")
		return ctrl.Result{}, nil
	}

	// Fetch the Cluster.
	cluster, err := util.GetClusterFromMetadata(ctx, r.Client, machine.ObjectMeta)
	if err != nil {
		log.Info("Machine is missing cluster label or cluster does not exist")
		return ctrl.Result{}, nil
	}

	if annotations.IsPaused(cluster, maasMachine) {
		log.Info("MaasMachine or linked Cluster is marked as paused. Won't reconcile")
		return ctrl.Result{}, nil
	}

	log = log.WithValues("cluster", cluster.Name)

	// Get Infra cluster
	maasCluster := &infrav1beta1.MaasCluster{}
	infraClusterName := client.ObjectKey{
		Namespace: maasMachine.Namespace,
		Name:      cluster.Spec.InfrastructureRef.Name,
	}

	if err := r.Client.Get(ctx, infraClusterName, maasCluster); err != nil {
		log.Info("MaasCluster is not available yet")
		return ctrl.Result{}, nil
	}

	// Create the cluster scope
	clusterScope, err := scope.NewClusterScope(scope.ClusterScopeParams{
		Client:         r.Client,
		Logger:         log,
		Cluster:        cluster,
		MaasCluster:    maasCluster,
		Tracker:        r.Tracker,
		ControllerName: "maasmachine",
	})
	if err != nil {
		return ctrl.Result{}, err
	}

	// Create the machine scope
	machineScope, err := scope.NewMachineScope(scope.MachineScopeParams{
		Logger:       log,
		Client:       r.Client,
		Tracker:      r.Tracker,
		Cluster:      cluster,
		ClusterScope: clusterScope,
		Machine:      machine,
		MaasMachine:  maasMachine,
	})
	if err != nil {
		log.Error(err, "failed to create scope")
		return ctrl.Result{}, err
	}

	// Always close the scope when exiting this function so we can persist any MaasMachine changes.
	defer func() {
		if err := machineScope.Close(); err != nil && rerr == nil {
			rerr = err
		}
	}()

	// Handle deleted machines
	if !maasMachine.DeletionTimestamp.IsZero() {
		return r.reconcileDelete(ctx, machineScope, clusterScope)
	}

	// Handle non-deleted machines
	return r.reconcileNormal(ctx, machineScope, clusterScope)
}

func (r *MaasMachineReconciler) reconcileDelete(_ context.Context, machineScope *scope.MachineScope, clusterScope *scope.ClusterScope) (ctrl.Result, error) {
	machineScope.Info("Reconciling MaasMachine delete")

	maasMachine := machineScope.MaasMachine

	machineSvc := maasmachine.NewService(machineScope)

	// Find existing instance
	m, err := r.findMachine(machineScope, machineSvc)
	if err != nil {
		machineScope.Error(err, "unable to find machine")
		return ctrl.Result{}, err
	}

	if m == nil {
		machineScope.V(2).Info("Unable to locate MaaS instance by ID or tags", "system-id", machineScope.GetInstanceID())
		r.Recorder.Eventf(maasMachine, corev1.EventTypeWarning, "NoMachineFound", "Unable to find matching MaaS machine")
		controllerutil.RemoveFinalizer(maasMachine, infrav1beta1.MachineFinalizer)
		return ctrl.Result{}, nil
	}

	if err := r.reconcileDNSAttachment(machineScope, clusterScope, m); err != nil {
		if errors.Is(err, ErrRequeueDNS) {
			return ctrl.Result{}, nil
			//return ctrl.Result{RequeueAfter: 10 * time.Second}, nil
		}

		machineScope.Error(err, "failed to reconcile LB attachment")
		return ctrl.Result{}, err
	}

	if err := machineSvc.ReleaseMachine(m.ID); err != nil {
		machineScope.Error(err, "failed to release machine")
		return ctrl.Result{}, err
	}

	conditions.MarkFalse(machineScope.MaasMachine, infrav1beta1.MachineDeployedCondition, clusterv1.DeletedReason, clusterv1.ConditionSeverityInfo, "")
	r.Recorder.Eventf(machineScope.MaasMachine, corev1.EventTypeNormal, "SuccessfulRelease", "Released instance %q", m.ID)

	// Machine is deleted so remove the finalizer.
	controllerutil.RemoveFinalizer(maasMachine, infrav1beta1.MachineFinalizer)

	//// v1alpah3 MAASMachine finalizer
	//// Machine is deleted so remove the finalizer.
	//controllerutil.RemoveFinalizer(maasMachine, infrav1alpha3.MachineFinalizer)

	return reconcile.Result{}, nil
}

// findInstance queries the EC2 apis and retrieves the instance if it exists, returns nil otherwise.
func (r *MaasMachineReconciler) findMachine(machineScope *scope.MachineScope, machineSvc *maasmachine.Service) (*infrav1beta1.Machine, error) {
	id := machineScope.GetInstanceID()
	if id == nil {
		return nil, nil
	}

	m, err := machineSvc.GetMachine(*id)
	if err != nil {
		return nil, errors.Wrapf(err, "Unable to find machine")
	}

	return m, nil
}

func (r *MaasMachineReconciler) reconcileNormal(_ context.Context, machineScope *scope.MachineScope, clusterScope *scope.ClusterScope) (ctrl.Result, error) {
	machineScope.Info("Reconciling MaasMachine")

	maasMachine := machineScope.MaasMachine

	// Add finalizer first if not exist to avoid the race condition between init and delete
	if !controllerutil.ContainsFinalizer(maasMachine, infrav1beta1.MachineFinalizer) {
		controllerutil.AddFinalizer(maasMachine, infrav1beta1.MachineFinalizer)
		return ctrl.Result{}, nil
	}

	if !machineScope.Cluster.Status.InfrastructureReady {
		machineScope.Info("Cluster infrastructure is not ready yet")
		conditions.MarkFalse(machineScope.MaasMachine, infrav1beta1.MachineDeployedCondition, infrav1beta1.WaitingForClusterInfrastructureReason, clusterv1.ConditionSeverityInfo, "")
		return ctrl.Result{}, nil
	}

	// Make sure bootstrap data is available and populated.
	if machineScope.Machine.Spec.Bootstrap.DataSecretName == nil {
		machineScope.Info("Bootstrap data secret reference is not yet available")
		conditions.MarkFalse(machineScope.MaasMachine, infrav1beta1.MachineDeployedCondition, infrav1beta1.WaitingForBootstrapDataReason, clusterv1.ConditionSeverityInfo, "")
		return ctrl.Result{}, nil
	}

	machineSvc := maasmachine.NewService(machineScope)

	// Find existing instance
	m, err := r.findMachine(machineScope, machineSvc)
	if err != nil {
		machineScope.Error(err, "unable to find m")
		conditions.MarkUnknown(machineScope.MaasMachine, infrav1beta1.MachineDeployedCondition, infrav1beta1.MachineNotFoundReason, err.Error())
		return ctrl.Result{}, err
	}

	// Create new m
	// TODO(saamalik) confirm that we'll never "recreate" a m; e.g: findMachine should always return err
	// if there used to be a m
	if m == nil || !(m.State == infrav1beta1.MachineStateDeployed || m.State == infrav1beta1.MachineStateDeploying) {
		// Avoid a flickering condition between Started and Failed if there's a persistent failure with createInstance
		if conditions.GetReason(machineScope.MaasMachine, infrav1beta1.MachineDeployedCondition) != infrav1beta1.MachineDeployFailedReason {
			conditions.MarkFalse(machineScope.MaasMachine, infrav1beta1.MachineDeployedCondition, infrav1beta1.MachineDeployStartedReason, clusterv1.ConditionSeverityInfo, "")
			if patchErr := machineScope.PatchObject(); patchErr != nil {
				machineScope.Error(patchErr, "failed to patch conditions")
				return ctrl.Result{}, patchErr
			}
		}
		m, err = r.deployMachine(machineScope, machineSvc)
		if err != nil {
			machineScope.Error(err, "unable to create m")
			conditions.MarkFalse(machineScope.MaasMachine, infrav1beta1.MachineDeployedCondition, infrav1beta1.MachineDeployFailedReason, clusterv1.ConditionSeverityError, err.Error())
			return ctrl.Result{}, err
		}
	}

	// Make sure Spec.ProviderID and Spec.InstanceID are always set.
	machineScope.SetProviderID(m.ID, m.AvailabilityZone)
	machineScope.SetFailureDomain(m.AvailabilityZone)
	machineScope.SetSystemID(m.ID)
	machineScope.SetMachineHostname(m.Hostname)

	existingMachineState := machineScope.GetMachineState()
	machineScope.Logger = machineScope.Logger.WithValues("state", m.State, "m-id", *machineScope.GetInstanceID())
	machineScope.SetMachineState(m.State)
	machineScope.SetPowered(m.Powered)

	// Proceed to reconcile the MaasMachine state.
	if existingMachineState == nil || *existingMachineState != m.State {
		machineScope.Info("MaaS m state changed", "old-state", existingMachineState)
	}

	switch s := m.State; {
	case s == infrav1beta1.MachineStateReady, s == infrav1beta1.MachineStateDiskErasing, s == infrav1beta1.MachineStateReleasing, s == infrav1beta1.MachineStateNew:
		machineScope.SetNotReady()
		machineScope.Info("Unexpected Maas m termination")
		r.Recorder.Eventf(machineScope.MaasMachine, corev1.EventTypeWarning, "MachineUnexpectedTermination", "Unexpected Maas m termination")
		conditions.MarkFalse(machineScope.MaasMachine, infrav1beta1.MachineDeployedCondition, infrav1beta1.MachineTerminatedReason, clusterv1.ConditionSeverityError, "")
		machineScope.SetFailureReason(capierrors.UpdateMachineError)
		machineScope.SetFailureMessage(errors.Errorf("Maas machine state %q is unexpected", m.State))
	case machineScope.MachineIsInKnownState() && !m.Powered:
		if *machineScope.GetMachineState() == infrav1beta1.MachineStateDeployed {
			machineScope.Info("Deployed machine is powered off trying power on")
			if err := machineSvc.PowerOnMachine(); err != nil {
				return ctrl.Result{}, errors.Wrap(err, "unable to power on deployed machine")
			}

			return ctrl.Result{RequeueAfter: 1 * time.Minute}, nil
		}

		machineScope.SetNotReady()
		machineScope.Info("Machine is powered off!")
		conditions.MarkFalse(machineScope.MaasMachine, infrav1beta1.MachineDeployedCondition, infrav1beta1.MachinePoweredOffReason, clusterv1.ConditionSeverityWarning, "")
	case s == infrav1beta1.MachineStateDeploying, s == infrav1beta1.MachineStateAllocated:
		machineScope.SetNotReady()
		conditions.MarkFalse(machineScope.MaasMachine, infrav1beta1.MachineDeployedCondition, infrav1beta1.MachineDeployingReason, clusterv1.ConditionSeverityWarning, "")
	case s == infrav1beta1.MachineStateDeployed:
		machineScope.SetReady()
		conditions.MarkTrue(machineScope.MaasMachine, infrav1beta1.MachineDeployedCondition)
	default:
		machineScope.SetNotReady()
		machineScope.Info("MaaS m state is undefined", "state", m.State)
		r.Recorder.Eventf(machineScope.MaasMachine, corev1.EventTypeWarning, "MachineUnhandledState", "MaaS m state is undefined")
		machineScope.SetFailureReason(capierrors.UpdateMachineError)
		machineScope.SetFailureMessage(errors.Errorf("MaaS m state %q is undefined", m.State))
		conditions.MarkUnknown(machineScope.MaasMachine, infrav1beta1.MachineDeployedCondition, "", "")
	}

	// tasks that can take place during all known instance states
	if machineScope.MachineIsInKnownState() {
		// TODO(saamalik) tags / labels

		// Set the address if good
		machineScope.SetAddresses(m.Addresses)

		if err := r.reconcileDNSAttachment(machineScope, clusterScope, m); err != nil {
			if errors.Is(err, ErrRequeueDNS) {
				return ctrl.Result{RequeueAfter: 10 * time.Second}, nil
			}
			machineScope.Error(err, "failed to reconcile DNS attachment")
			return ctrl.Result{}, err
		}
	}

	// tasks that can only take place during operational instance states
	// Tried to not requeue here, but during error conditions (e.g: machine fails to boot)
	// there is no easy way to check other than a requeue
	if o, _ := clusterScope.IsAPIServerOnline(); !o {
		machineScope.Info("API Server is not online; requeue")
		return ctrl.Result{RequeueAfter: 5 * time.Minute}, nil
	} else if !machineScope.MachineIsOperational() {
		machineScope.Info("Machine is not operational; requeue")
		return ctrl.Result{RequeueAfter: 5 * time.Minute}, nil
	} else {
		if err := machineScope.SetNodeProviderID(); err != nil {
			machineScope.Error(err, "Unable to set Node hostname")
			r.Recorder.Eventf(machineScope.MaasMachine, corev1.EventTypeWarning, "NodeProviderUpdateFailed", "Unable to set the node provider update")
			return ctrl.Result{RequeueAfter: 30 * time.Second}, nil
		}
	}

	return ctrl.Result{}, nil
}

func (r *MaasMachineReconciler) deployMachine(machineScope *scope.MachineScope, machineSvc *maasmachine.Service) (*infrav1beta1.Machine, error) {
	machineScope.Info("Deploying on MaaS machine")

	userDataB64, userDataErr := r.resolveUserData(machineScope)
	if userDataErr != nil {
		return nil, errors.Wrapf(userDataErr, "failed to resolve userdata")
	}

	m, err := machineSvc.DeployMachine(userDataB64)
	if err != nil {
		return nil, errors.Wrapf(err, "failed to deploy MaasMachine instance")
	}

	return m, nil
}

func (r *MaasMachineReconciler) resolveUserData(machineScope *scope.MachineScope) (string, error) {
	userData, err := machineScope.GetRawBootstrapData()
	if err != nil {
		r.Recorder.Eventf(machineScope.MaasMachine, corev1.EventTypeWarning, "FailedGetBootstrapData", err.Error())
		return "", err
	}

	// Base64 encode the userdata
	return base64.StdEncoding.EncodeToString(userData), nil
}

func (r *MaasMachineReconciler) reconcileDNSAttachment(machineScope *scope.MachineScope, clusterScope *scope.ClusterScope, m *infrav1beta1.Machine) error {
	if !machineScope.IsControlPlane() {
		return nil
	}

	dnssvc := maasdns.NewService(clusterScope)

	// In order to prevent sending request to a "not-ready" control plane machines, it is required to remove the machine
	// from the DNS as soon as the machine gets deleted or when the machine is in a not running state.
	if !machineScope.MaasMachine.DeletionTimestamp.IsZero() || !machineScope.MachineIsRunning() {
		registered, err := dnssvc.MachineIsRegisteredWithAPIServerDNS(m)
		if err != nil {
			//r.Recorder.Eventf(machineScope.MaasMachine, corev1.EventTypeWarning, "FailedDetachControlPlaneDNS",
			//	"Failed to deregister control plane instance %q from DNS: failed to determine registration status: %v", m.ID, err)
			return errors.Wrapf(err, "machine %q - error determining registration status", m.ID)
		}

		machineScope.MaasMachine.Status.DNSAttached = registered

		if registered {
			// Wait for Cluster to delete this guy
			conditions.MarkFalse(machineScope.MaasMachine, infrav1beta1.DNSAttachedCondition, infrav1beta1.DNSDetachPending, clusterv1.ConditionSeverityWarning, "")
			machineScope.Info("machine waiting for cluster to de-register DNS")
			return ErrRequeueDNS
		}

		// Already deregistered - nothing more to do
		return nil
	}

	registered, err := dnssvc.MachineIsRegisteredWithAPIServerDNS(m)
	if err != nil {
		//r.Recorder.Eventf(machineScope.MaasMachine, corev1.EventTypeWarning, "FailedAttachControlPlaneELB",
		//	"Failed to register control plane instance %q with load balancer: failed to determine registration status: %v", i.ID, err)
		return errors.Wrapf(err, "normal machine %q - error determining registration status", m.ID)
	}

	machineScope.MaasMachine.Status.DNSAttached = registered

	if !registered {
		conditions.MarkFalse(machineScope.MaasMachine, infrav1beta1.DNSAttachedCondition, infrav1beta1.DNSAttachPending, clusterv1.ConditionSeverityWarning, "")
		// Wait for Cluster to add me
		machineScope.Info("machine waiting for cluster to register DNS")
		return ErrRequeueDNS
	}

	conditions.MarkTrue(machineScope.MaasMachine, infrav1beta1.DNSAttachedCondition)

	// Already registered - nothing more to do
	return nil
}

// SetupWithManager will add watches for this controller
func (r *MaasMachineReconciler) SetupWithManager(_ context.Context, mgr ctrl.Manager, options controller.Options) error {
	clusterToMaasMachines, err := util.ClusterToObjectsMapper(mgr.GetClient(), &infrav1beta1.MaasMachineList{}, mgr.GetScheme())
	if err != nil {
		return err
	}

	c, err := ctrl.NewControllerManagedBy(mgr).
		For(&infrav1beta1.MaasMachine{}).
		WithOptions(options).
		Watches(
			&source.Kind{Type: &clusterv1.Machine{}},
			handler.EnqueueRequestsFromMapFunc(util.MachineToInfrastructureMapFunc(infrav1beta1.GroupVersion.WithKind("MaasMachine"))),
		).
		Watches(
			&source.Kind{Type: &infrav1beta1.MaasCluster{}},
			handler.EnqueueRequestsFromMapFunc(r.MaasClusterToMaasMachines),
		).
		WithEventFilter(predicates.ResourceNotPaused(r.Log)).
		Build(r)
	if err != nil {
		return err
	}
	return c.Watch(
		&source.Kind{Type: &clusterv1.Cluster{}},
		handler.EnqueueRequestsFromMapFunc(clusterToMaasMachines),
		predicates.ClusterUnpausedAndInfrastructureReady(r.Log),
	)
}

// MaasClusterToMaasMachines is a handler.ToRequestsFunc to be used to enqeue
// requests for reconciliation of MaasMachines.
func (r *MaasMachineReconciler) MaasClusterToMaasMachines(o client.Object) []ctrl.Request {
	var result []ctrl.Request
	c, ok := o.(*infrav1beta1.MaasCluster)
	if !ok {
		panic(fmt.Sprintf("Expected a MaasCluster but got a %T", o))
	}

	cluster, err := util.GetOwnerCluster(context.TODO(), r.Client, c.ObjectMeta)
	switch {
	case apierrors.IsNotFound(err) || cluster == nil:
		return result
	case err != nil:
		return result
	}

	labels := map[string]string{clusterv1.ClusterLabelName: cluster.Name}
	machineList := &clusterv1.MachineList{}
	if err := r.Client.List(context.TODO(), machineList, client.InNamespace(c.Namespace), client.MatchingLabels(labels)); err != nil {
		return nil
	}
	for _, m := range machineList.Items {
		if m.Spec.InfrastructureRef.Name == "" {
			continue
		}
		name := client.ObjectKey{Namespace: m.Spec.InfrastructureRef.Namespace, Name: m.Spec.InfrastructureRef.Name}
		result = append(result, ctrl.Request{NamespacedName: name})
	}

	return result
}