bootstrap

package
v0.9.1 Latest Latest
Warning

This package is not in the latest version of its module.

Go to latest
Published: Aug 18, 2023 License: Apache-2.0 Imports: 27 Imported by: 1

Documentation

Overview

Package bootstrap implements utilities for boostrapping a kube cluster with resources on controller start.

This is typically used to bootstrap CRDs and CRs (of the types defined by the CRDs) so that a controller can be continuously deployed and still include breaking changes.

The bootstrap approach allows the controller to determine when and how to coordinate updates to the apis it manages. It should not typically be used by end-users of an operator, who may be using one or more other tools to manage the deployment of the operator and the resources it manages, and may not wish to grant the privileges required to bootstrap.

Index

Examples

Constants

This section is empty.

Variables

This section is empty.

Functions

func CRD

func CRD(restConfig *rest.Config, crdFS fs.ReadDirFS, dir string) error

CRD installs the CRDs in the filesystem into the kube cluster configured by the rest config. Deprecated: Use CRDs instead.

Example
package main

import (
	"context"
	"embed"

	"k8s.io/client-go/rest"
)

//go:embed example/*.yaml
var crdFS embed.FS

func main() {
	_ = CRDs(context.Background(), &rest.Config{}, crdFS, "example")
}
Output:

func CRDs added in v0.9.0

func CRDs(ctx context.Context, restConfig *rest.Config, crdFS fs.ReadDirFS, dir string) error

CRDs installs the CRDs in the filesystem into the kube cluster configured by the rest config.

func ResourceFromFile

func ResourceFromFile[O KubeResourceObject](ctx context.Context, fieldManager string, gvr schema.GroupVersionResource, dclient dynamic.Interface, configPath string, lastHash uint64) (uint64, error)

ResourceFromFile creates a KubeResourceObject with the given config file

Example
package main

import (
	"bytes"
	"context"
	"fmt"
	"time"

	"github.com/go-logr/logr"
	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/runtime/schema"
	"k8s.io/apimachinery/pkg/util/yaml"
	"k8s.io/client-go/dynamic/fake"
	"k8s.io/client-go/testing"
	"k8s.io/klog/v2/klogr"
)

func main() {
	ctx, cancel := context.WithCancel(logr.NewContext(context.Background(), klogr.New()))
	defer cancel()

	secretGVR := corev1.SchemeGroupVersion.WithResource("secrets")
	scheme := runtime.NewScheme()
	if err := corev1.AddToScheme(scheme); err != nil {
		panic(err)
	}
	scheme.AddKnownTypes(corev1.SchemeGroupVersion, &corev1.Secret{})
	client := secretApplyPatchHandlingFakeClient(scheme)

	// create the object from the file
	// the example is a secret, but it could be any built-in or CRD-defined type
	_, err := ResourceFromFile[*corev1.Secret](ctx, "bootstrapped-secret", secretGVR, client, "./example.yaml", 0)
	if err != nil {
		panic(err)
	}

	for {
		secret, err := client.Resource(secretGVR).Namespace("test").Get(ctx, "example", metav1.GetOptions{})
		if err == nil {
			fmt.Printf("%s/%s", secret.GetNamespace(), secret.GetName())
			break
		}
		time.Sleep(1 * time.Millisecond)
	}
}

// secretApplyPatchHandlingFakeClient creates a fake client that handles
// apply patch types (for corev1.Secret only).
func secretApplyPatchHandlingFakeClient(scheme *runtime.Scheme) *fake.FakeDynamicClient {
	client := fake.NewSimpleDynamicClientWithCustomListKinds(scheme, map[schema.GroupVersionResource]string{})
	client.PrependReactor("patch", "secrets", func(action testing.Action) (handled bool, ret runtime.Object, err error) {
		decoder := yaml.NewYAMLToJSONDecoder(bytes.NewReader(action.(testing.PatchAction).GetPatch()))
		var secret corev1.Secret
		if err := decoder.Decode(&secret); err != nil {
			return true, nil, err
		}
		// server-side apply creates the object if it doesn't exist
		if err := client.Tracker().Add(&secret); err != nil {
			return true, nil, err
		}
		return true, &secret, nil
	})
	return client
}
Output:

test/example

Types

type KubeResourceObject

type KubeResourceObject interface {
	metav1.Object
	runtime.Object
}

KubeResourceObject is satisfied by any standard kube object.

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL