cloudfoundry/cf-k8s-controllers

package k8s

import (
    "context"
    "fmt"

    "github.com/go-logr/logr"
    "github.com/google/uuid"
    apierrors "k8s.io/apimachinery/pkg/api/errors"
    ctrl "sigs.k8s.io/controller-runtime"
    "sigs.k8s.io/controller-runtime/pkg/builder"
    "sigs.k8s.io/controller-runtime/pkg/client"
)

type ObjectReconciler[T any, PT ObjectWithDeepCopy[T]] interface {
    ReconcileResource(ctx context.Context, obj PT) (ctrl.Result, error)
    SetupWithManager(mgr ctrl.Manager) *builder.Builder
}

type PatchingReconciler[T any, PT ObjectWithDeepCopy[T]] struct {
    log              logr.Logger
    k8sClient        client.Client
    objectReconciler ObjectReconciler[T, PT]
}

func NewPatchingReconciler[T any, PT ObjectWithDeepCopy[T]](log logr.Logger, k8sClient client.Client, objectReconciler ObjectReconciler[T, PT]) *PatchingReconciler[T, PT] {
    return &PatchingReconciler[T, PT]{
        log:              log,
        k8sClient:        k8sClient,
        objectReconciler: objectReconciler,
    }
}

func (r *PatchingReconciler[T, PT]) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
    log := r.log.WithValues("namespace", req.Namespace, "name", req.Name, "logID", uuid.NewString())
    ctx = logr.NewContext(ctx, log)

    obj := PT(new(T))
    err := r.k8sClient.Get(ctx, req.NamespacedName, obj)
    if err != nil {
        if apierrors.IsNotFound(err) {
            return ctrl.Result{}, nil
        }
        log.Info(fmt.Sprintf("unable to fetch %T", obj), "reason", err)
        return ctrl.Result{}, err
    }

    var (
        result      ctrl.Result
        delegateErr error
    )

    err = Patch(ctx, r.k8sClient, obj, func() {
        result, delegateErr = r.objectReconciler.ReconcileResource(ctx, obj)
    })
    if err != nil {
        log.Info("patch object failed", "reason", err)
        return ctrl.Result{}, err
    }

    return result, delegateErr
}

func (r *PatchingReconciler[T, PT]) SetupWithManager(mgr ctrl.Manager) error {
    return r.objectReconciler.SetupWithManager(mgr).Complete(r)
}