You said something about main?

But first, remember how we said we’d come back to main.go again? Let’s take a look and see what’s changed, and what we need to add.

Apache License

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.

Imports



package main

import (
    "flag"
    "os"

    kbatchv1beta1 "k8s.io/api/batch/v1"
    "k8s.io/apimachinery/pkg/runtime"
    _ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
    ctrl "sigs.k8s.io/controller-runtime"
    "sigs.k8s.io/controller-runtime/pkg/log/zap"
    batchv1 "tutorial.kubebuilder.io/project/api/v1"
    "tutorial.kubebuilder.io/project/controllers"
    // +kubebuilder:scaffold:imports
)

The first difference to notice is that kubebuilder has added the new API group’s package (kbatchv1beta1) to our scheme. This means that we can use those objects in our controller.

We’ll also need to add the kubernetes batch v1 scheme, since we’re creating and listing Jobs.


var (
    scheme   = runtime.NewScheme()
    setupLog = ctrl.Log.WithName("setup")
)

func init() {

    kbatchv1beta1.AddToScheme(scheme) // we've added this ourselves
    batchv1.AddToScheme(scheme)
    // +kubebuilder:scaffold:scheme
}

The other thing that’s changed is that kubebuilder has added a block calling our CronJob controller’s SetupWithManager method. Since we now use a Scheme as well, we’ll need to pass that to the reconciler ourselves.



func main() {

old stuff


    var metricsAddr string
    flag.StringVar(&metricsAddr, "metrics-addr", ":8080", "The address the metric endpoint binds to.")
    flag.Parse()

    ctrl.SetLogger(zap.Logger(true))

    mgr, err := ctrl.NewManager(ctrl.GetConfigOrDie(), ctrl.Options{Scheme: scheme, MetricsBindAddress: metricsAddr})
    if err != nil {
        setupLog.Error(err, "unable to start manager")
        os.Exit(1)
    }



    err = (&controllers.CronJobReconciler{
        Client: mgr.GetClient(),
        Log:    ctrl.Log.WithName("controllers").WithName("CronJob"),
        Scheme: mgr.GetScheme(), // we've added this ourselves
    }).SetupWithManager(mgr)
    if err != nil {
        setupLog.Error(err, "unable to create controller", "controller", "CronJob")
        os.Exit(1)
    }
    // +kubebuilder:scaffold:builder

old stuff



    setupLog.Info("starting manager")
    if err := mgr.Start(ctrl.SetupSignalHandler()); err != nil {
        setupLog.Error(err, "problem running manager")
        os.Exit(1)
    }

Now we can implement our controller.

The Kubebuilder Book

You said something about main?