github.com/cilium/cilium@v1.16.2/operator/pkg/gateway-api/httproute.go

// SPDX-License-Identifier: Apache-2.0
// Copyright Authors of Cilium

package gateway_api

import (
	"context"

	"github.com/sirupsen/logrus"
	corev1 "k8s.io/api/core/v1"
	"k8s.io/apimachinery/pkg/fields"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/types"
	ctrl "sigs.k8s.io/controller-runtime"
	"sigs.k8s.io/controller-runtime/pkg/builder"
	"sigs.k8s.io/controller-runtime/pkg/client"
	"sigs.k8s.io/controller-runtime/pkg/handler"
	"sigs.k8s.io/controller-runtime/pkg/predicate"
	"sigs.k8s.io/controller-runtime/pkg/reconcile"
	gatewayv1 "sigs.k8s.io/gateway-api/apis/v1"
	gatewayv1beta1 "sigs.k8s.io/gateway-api/apis/v1beta1"
	mcsapiv1alpha1 "sigs.k8s.io/mcs-api/pkg/apis/v1alpha1"

	"github.com/cilium/cilium/operator/pkg/gateway-api/helpers"
	"github.com/cilium/cilium/pkg/logging/logfields"
)

// httpRouteReconciler reconciles a HTTPRoute object
type httpRouteReconciler struct {
	client.Client
	Scheme *runtime.Scheme
}

func newHTTPRouteReconciler(mgr ctrl.Manager) *httpRouteReconciler {
	return &httpRouteReconciler{
		Client: mgr.GetClient(),
		Scheme: mgr.GetScheme(),
	}
}

// SetupWithManager sets up the controller with the Manager.
func (r *httpRouteReconciler) SetupWithManager(mgr ctrl.Manager) error {
	if err := mgr.GetFieldIndexer().IndexField(context.Background(), &gatewayv1.HTTPRoute{}, backendServiceIndex,
		func(rawObj client.Object) []string {
			route, ok := rawObj.(*gatewayv1.HTTPRoute)
			if !ok {
				return nil
			}
			var backendServices []string
			for _, rule := range route.Spec.Rules {
				for _, backend := range rule.BackendRefs {
					namespace := helpers.NamespaceDerefOr(backend.Namespace, route.Namespace)
					backendServiceName, err := helpers.GetBackendServiceName(r.Client, namespace, backend.BackendObjectReference)
					if err != nil {
						log.WithFields(logrus.Fields{
							logfields.Controller: "httpRoute",
							logfields.Resource:   client.ObjectKeyFromObject(rawObj),
						}).WithError(err).Error("Failed to get backend service name")
						continue
					}
					backendServices = append(backendServices,
						types.NamespacedName{
							Namespace: helpers.NamespaceDerefOr(backend.Namespace, route.Namespace),
							Name:      backendServiceName,
						}.String(),
					)
				}
			}
			return backendServices
		},
	); err != nil {
		return err
	}

	if err := mgr.GetFieldIndexer().IndexField(context.Background(), &gatewayv1beta1.HTTPRoute{}, backendServiceImportIndex,
		func(rawObj client.Object) []string {
			hr, ok := rawObj.(*gatewayv1beta1.HTTPRoute)
			if !ok {
				return nil
			}
			var backendServiceImports []string
			for _, rule := range hr.Spec.Rules {
				for _, backend := range rule.BackendRefs {
					if !helpers.IsServiceImport(backend.BackendObjectReference) {
						continue
					}
					backendServiceImports = append(backendServiceImports,
						types.NamespacedName{
							Namespace: helpers.NamespaceDerefOr(backend.Namespace, hr.Namespace),
							Name:      string(backend.Name),
						}.String(),
					)
				}
			}
			return backendServiceImports
		},
	); err != nil {
		return err
	}

	if err := mgr.GetFieldIndexer().IndexField(context.Background(), &gatewayv1.HTTPRoute{}, gatewayIndex,
		func(rawObj client.Object) []string {
			hr := rawObj.(*gatewayv1.HTTPRoute)
			var gateways []string
			for _, parent := range hr.Spec.ParentRefs {
				if !helpers.IsGateway(parent) {
					continue
				}
				gateways = append(gateways,
					types.NamespacedName{
						Namespace: helpers.NamespaceDerefOr(parent.Namespace, hr.Namespace),
						Name:      string(parent.Name),
					}.String(),
				)
			}
			return gateways
		},
	); err != nil {
		return err
	}

	builder := ctrl.NewControllerManagedBy(mgr).
		// Watch for changes to HTTPRoute
		For(&gatewayv1.HTTPRoute{},
			builder.WithPredicates(predicate.NewPredicateFuncs(r.hasGatewayParent()))).
		// Watch for changes to Backend services
		Watches(&corev1.Service{}, r.enqueueRequestForBackendService()).
		// Watch for changes to Reference Grants
		Watches(&gatewayv1beta1.ReferenceGrant{}, r.enqueueRequestForReferenceGrant()).
		// Watch for changes to Gateways and enqueue HTTPRoutes that reference them
		Watches(&gatewayv1.Gateway{}, r.enqueueRequestForGateway(),
			builder.WithPredicates(
				predicate.NewPredicateFuncs(hasMatchingController(context.Background(), mgr.GetClient(), controllerName))))

	if helpers.HasServiceImportSupport(r.Client.Scheme()) {
		// Watch for changes to Backend Service Imports
		builder = builder.Watches(&mcsapiv1alpha1.ServiceImport{}, r.enqueueRequestForBackendServiceImport())
	}

	return builder.Complete(r)
}

func (r *httpRouteReconciler) hasGatewayParent() func(object client.Object) bool {
	return func(obj client.Object) bool {
		hr, ok := obj.(*gatewayv1.HTTPRoute)
		if !ok {
			return false
		}

		for _, parent := range hr.Spec.ParentRefs {
			if helpers.IsGateway(parent) {
				return true
			}
		}

		return false
	}
}

// enqueueRequestForBackendService makes sure that HTTP Routes are reconciled
// if the backend services are updated.
func (r *httpRouteReconciler) enqueueRequestForBackendService() handler.EventHandler {
	return handler.EnqueueRequestsFromMapFunc(r.enqueueFromIndex(backendServiceIndex))
}

// enqueueRequestForBackendServiceImport makes sure that HTTP Routes are reconciled
// if the backend Service Imports are updated.
func (r *httpRouteReconciler) enqueueRequestForBackendServiceImport() handler.EventHandler {
	return handler.EnqueueRequestsFromMapFunc(r.enqueueFromIndex(backendServiceImportIndex))
}

// enqueueRequestForReferenceGrant makes sure that all HTTP Routes are reconciled
// if a ReferenceGrant changes
func (r *httpRouteReconciler) enqueueRequestForReferenceGrant() handler.EventHandler {
	return handler.EnqueueRequestsFromMapFunc(r.enqueueAll())
}

func (r *httpRouteReconciler) enqueueRequestForGateway() handler.EventHandler {
	return handler.EnqueueRequestsFromMapFunc(r.enqueueFromIndex(gatewayIndex))
}

func (r *httpRouteReconciler) enqueueFromIndex(index string) handler.MapFunc {
	return func(ctx context.Context, o client.Object) []reconcile.Request {
		scopedLog := log.WithFields(logrus.Fields{
			logfields.Controller: "httpRoute",
			logfields.Resource:   client.ObjectKeyFromObject(o),
		})
		hrList := &gatewayv1.HTTPRouteList{}

		if err := r.Client.List(ctx, hrList, &client.ListOptions{
			FieldSelector: fields.OneTermEqualSelector(index, client.ObjectKeyFromObject(o).String()),
		}); err != nil {
			scopedLog.WithError(err).Error("Failed to get related HTTPRoutes")
			return []reconcile.Request{}
		}

		requests := make([]reconcile.Request, 0, len(hrList.Items))
		for _, item := range hrList.Items {
			route := client.ObjectKey{
				Namespace: item.GetNamespace(),
				Name:      item.GetName(),
			}
			requests = append(requests, reconcile.Request{
				NamespacedName: route,
			})
			scopedLog.WithField("httpRoute", route).Info("Enqueued HTTPRoute for resource")
		}
		return requests
	}
}

func (r *httpRouteReconciler) enqueueAll() handler.MapFunc {
	return func(ctx context.Context, o client.Object) []reconcile.Request {
		scopedLog := log.WithFields(logrus.Fields{
			logfields.Controller: "httpRoute",
			logfields.Resource:   client.ObjectKeyFromObject(o),
		})
		hrList := &gatewayv1.HTTPRouteList{}

		if err := r.Client.List(ctx, hrList, &client.ListOptions{}); err != nil {
			scopedLog.WithError(err).Error("Failed to get HTTPRoutes")
			return []reconcile.Request{}
		}

		requests := make([]reconcile.Request, 0, len(hrList.Items))
		for _, item := range hrList.Items {
			route := client.ObjectKey{
				Namespace: item.GetNamespace(),
				Name:      item.GetName(),
			}
			requests = append(requests, reconcile.Request{
				NamespacedName: route,
			})
			scopedLog.WithField("httpRoute", route).Info("Enqueued HTTPRoute for resource")
		}
		return requests
	}
}