traveller_controller.go

package traveller

import (
	"context"

	examplev1alpha1 "operator/hello-operator/pkg/apis/example/v1alpha1"

	appsv1 "k8s.io/api/apps/v1"
	corev1 "k8s.io/api/core/v1"
	"k8s.io/apimachinery/pkg/api/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/types"
	"k8s.io/apimachinery/pkg/util/intstr"
	"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"
	logf "sigs.k8s.io/controller-runtime/pkg/log"
	"sigs.k8s.io/controller-runtime/pkg/manager"
	"sigs.k8s.io/controller-runtime/pkg/reconcile"
	"sigs.k8s.io/controller-runtime/pkg/source"
)

var log = logf.Log.WithName("controller_traveller")

/**
* USER ACTION REQUIRED: This is a scaffold file intended for the user to modify with their own Controller
* business logic.  Delete these comments after modifying this file.*
 */

// Add creates a new Traveller Controller and adds it to the Manager. The Manager will set fields on the Controller
// and Start it when the Manager is Started.
func Add(mgr manager.Manager) error {
	return add(mgr, newReconciler(mgr))
}

// newReconciler returns a new reconcile.Reconciler
func newReconciler(mgr manager.Manager) reconcile.Reconciler {
	return &ReconcileTraveller{client: mgr.GetClient(), scheme: mgr.GetScheme()}
}

// add adds a new Controller to mgr with r as the reconcile.Reconciler
func add(mgr manager.Manager, r reconcile.Reconciler) error {
	// Create a new controller
	c, err := controller.New("traveller-controller", mgr, controller.Options{Reconciler: r})
	if err != nil {
		return err
	}

	// Watch for changes to primary resource Traveller
	err = c.Watch(&source.Kind{Type: &examplev1alpha1.Traveller{}}, &handler.EnqueueRequestForObject{})
	if err != nil {
		return err
	}

	// TODO(user): Modify this to be the types you create that are owned by the primary resource
	// Watch for changes to secondary resource Pods and requeue the owner Traveller
	err = c.Watch(&source.Kind{Type: &corev1.Pod{}}, &handler.EnqueueRequestForOwner{
		IsController: true,
		OwnerType:    &examplev1alpha1.Traveller{},
	})
	if err != nil {
		return err
	}

	return nil
}

// blank assignment to verify that ReconcileTraveller implements reconcile.Reconciler
var _ reconcile.Reconciler = &ReconcileTraveller{}

// ReconcileTraveller reconciles a Traveller object
type ReconcileTraveller struct {
	// This client, initialized using mgr.Client() above, is a split client
	// that reads objects from the cache and writes to the apiserver
	client client.Client
	scheme *runtime.Scheme
}

// Reconcile reads that state of the cluster for a Traveller object and makes changes based on the state read
// and what is in the Traveller.Spec
// TODO(user): Modify this Reconcile function to implement your Controller logic.  This example creates
// a Pod as an example
// Note:
// The Controller will requeue the Request to be processed again if the returned error is non-nil or
// Result.Requeue is true, otherwise upon completion it will remove the work from the queue.
func (r *ReconcileTraveller) Reconcile(request reconcile.Request) (reconcile.Result, error) {
	reqLogger := log.WithValues("Request.Namespace", request.Namespace, "Request.Name", request.Name)
	reqLogger.Info("Reconciling Traveller")

	// Fetch the Traveller instance
	instance := &examplev1alpha1.Traveller{}
	err := r.client.Get(context.TODO(), request.NamespacedName, instance)
	if err != nil {
		if errors.IsNotFound(err) {
			// Request object not found, could have been deleted after reconcile request.
			// Owned objects are automatically garbage collected. For additional cleanup logic use finalizers.
			// Return and don't requeue
			return reconcile.Result{}, nil
		}
		// Error reading the object - requeue the request.
		return reconcile.Result{}, err
	}

	// Check if this Deployment already exists
	found := &appsv1.Deployment{}
	err = r.client.Get(context.TODO(), types.NamespacedName{Name: instance.Name, Namespace: instance.Namespace}, found)

	var result *reconcile.Result
	result, err = r.ensureDeployment(request, instance, r.backendDeployment(instance))
	if result != nil {
		return *result, err
	}

	result, err = r.ensureService(request, instance, r.backendService(instance))
	if result != nil {
		return *result, err
	}
	// Deployment and Service already exists - don't requeue
	reqLogger.Info("Skip reconcile: Deployment and service already exists",
		"Deployment.Namespace", found.Namespace, "Deployment.Name", found.Name)
	return reconcile.Result{}, nil
}

func labels(v *examplev1alpha1.Traveller, tier string) map[string]string {
	// Fetches and sets labels

	return map[string]string{
		"app":             "visitors",
		"visitorssite_cr": v.Name,
		"tier":            tier,
	}
}

func (r *ReconcileTraveller) backendService(v *examplev1alpha1.Traveller) *corev1.Service {
	// Build a Service

	labels := labels(v, "backend")

	s := &corev1.Service{
		ObjectMeta: metav1.ObjectMeta{
			Name:      "backend-service",
			Namespace: v.Namespace,
		},
		Spec: corev1.ServiceSpec{
			Selector: labels,
			Ports: []corev1.ServicePort{{
				Protocol:   corev1.ProtocolTCP,
				Port:       80,
				TargetPort: intstr.FromInt(8080),
				NodePort:   30685,
			}},
			Type: corev1.ServiceTypeNodePort,
		},
	}

	controllerutil.SetControllerReference(v, s, r.scheme)
	return s
}

func (r *ReconcileTraveller) backendDeployment(v *examplev1alpha1.Traveller) *appsv1.Deployment {
	// Build a Deployment

	labels := labels(v, "backend")
	size := v.Spec.Size

	dep := &appsv1.Deployment{
		ObjectMeta: metav1.ObjectMeta{
			Name:      "hello-pod",
			Namespace: v.Namespace,
		},
		Spec: appsv1.DeploymentSpec{
			Replicas: &size,
			Selector: &metav1.LabelSelector{
				MatchLabels: labels,
			},
			Template: corev1.PodTemplateSpec{
				ObjectMeta: metav1.ObjectMeta{
					Labels: labels,
				},
				Spec: corev1.PodSpec{
					Containers: []corev1.Container{{
						Image:           v.Spec.Image,
						ImagePullPolicy: corev1.PullAlways,
						Name:            "hello-pod",
						Ports: []corev1.ContainerPort{{
							ContainerPort: 8080,
							Name:          "hello",
						}},
					}},
				},
			},
		},
	}

	controllerutil.SetControllerReference(v, dep, r.scheme)
	return dep
}

func (r *ReconcileTraveller) ensureService(request reconcile.Request,
	instance *examplev1alpha1.Traveller,
	s *corev1.Service,
) (*reconcile.Result, error) {

	// See if service already exists and create if it doesn't
	found := &appsv1.Deployment{}
	err := r.client.Get(context.TODO(), types.NamespacedName{
		Name:      s.Name,
		Namespace: instance.Namespace,
	}, found)
	if err != nil && errors.IsNotFound(err) {

		// Create the service
		log.Info("Creating a new Service", "Service.Namespace", s.Namespace, "Service.Name", s.Name)
		err = r.client.Create(context.TODO(), s)

		if err != nil {
			// Service creation failed
			log.Error(err, "Failed to create new Service", "Service.Namespace", s.Namespace, "Service.Name", s.Name)
			return &reconcile.Result{}, err
		} else {
			// Service creation was successful
			return nil, nil
		}
	} else if err != nil {
		// Error that isn't due to the service not existing
		log.Error(err, "Failed to get Service")
		return &reconcile.Result{}, err
	}

	return nil, nil
}

func (r *ReconcileTraveller) ensureDeployment(request reconcile.Request,
	instance *examplev1alpha1.Traveller,
	dep *appsv1.Deployment,
) (*reconcile.Result, error) {

	// See if deployment already exists and create if it doesn't
	found := &appsv1.Deployment{}
	err := r.client.Get(context.TODO(), types.NamespacedName{
		Name:      dep.Name,
		Namespace: instance.Namespace,
	}, found)
	if err != nil && errors.IsNotFound(err) {

		// Create the deployment
		log.Info("Creating a new Deployment", "Deployment.Namespace", dep.Namespace, "Deployment.Name", dep.Name)
		err = r.client.Create(context.TODO(), dep)

		if err != nil {
			// Deployment failed
			log.Error(err, "Failed to create new Deployment", "Deployment.Namespace", dep.Namespace, "Deployment.Name", dep.Name)
			return &reconcile.Result{}, err
		} else {
			// Deployment was successful
			return nil, nil
		}
	} else if err != nil {
		// Error that isn't due to the deployment not existing
		log.Error(err, "Failed to get Deployment")
		return &reconcile.Result{}, err
	}

	return nil, nil
}