helm/pkg/kube/client.go

/*
Copyright The Helm Authors.

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.
*/

package kube // import "helm.sh/helm/v4/pkg/kube"

import (
	"bytes"
	"context"
	"encoding/json"
	"fmt"
	"io"
	"log/slog"
	"os"
	"path/filepath"
	"reflect"
	"strings"
	"sync"

	jsonpatch "github.com/evanphx/json-patch"
	"github.com/pkg/errors"
	v1 "k8s.io/api/core/v1"
	apiextv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
	apiextv1beta1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1beta1"
	apierrors "k8s.io/apimachinery/pkg/api/errors"
	"k8s.io/apimachinery/pkg/runtime"
	"sigs.k8s.io/controller-runtime/pkg/client/apiutil"

	"k8s.io/apimachinery/pkg/api/meta"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
	metav1beta1 "k8s.io/apimachinery/pkg/apis/meta/v1beta1"
	"k8s.io/apimachinery/pkg/labels"
	"k8s.io/apimachinery/pkg/types"
	"k8s.io/apimachinery/pkg/util/strategicpatch"
	"k8s.io/cli-runtime/pkg/genericclioptions"
	"k8s.io/cli-runtime/pkg/resource"
	"k8s.io/client-go/kubernetes"
	"k8s.io/client-go/kubernetes/scheme"
	"k8s.io/client-go/rest"
	"k8s.io/client-go/util/retry"
	cmdutil "k8s.io/kubectl/pkg/cmd/util"
)

// ErrNoObjectsVisited indicates that during a visit operation, no matching objects were found.
var ErrNoObjectsVisited = errors.New("no objects visited")

var metadataAccessor = meta.NewAccessor()

// ManagedFieldsManager is the name of the manager of Kubernetes managedFields
// first introduced in Kubernetes 1.18
var ManagedFieldsManager string

// Client represents a client capable of communicating with the Kubernetes API.
type Client struct {
	// Factory provides a minimal version of the kubectl Factory interface. If
	// you need the full Factory you can type switch to the full interface.
	// Since Kubernetes Go API does not provide backwards compatibility across
	// minor versions, this API does not follow Helm backwards compatibility.
	// Helm is exposing Kubernetes in this property and cannot guarantee this
	// will not change. The minimal interface only has the functions that Helm
	// needs. The smaller surface area of the interface means there is a lower
	// chance of it changing.
	Factory Factory
	// Namespace allows to bypass the kubeconfig file for the choice of the namespace
	Namespace string

	Waiter
	kubeClient kubernetes.Interface
}

type WaitStrategy string

const (
	StatusWatcherStrategy WaitStrategy = "watcher"
	LegacyStrategy        WaitStrategy = "legacy"
	HookOnlyStrategy      WaitStrategy = "hookOnly"
)

func init() {
	// Add CRDs to the scheme. They are missing by default.
	if err := apiextv1.AddToScheme(scheme.Scheme); err != nil {
		// This should never happen.
		panic(err)
	}
	if err := apiextv1beta1.AddToScheme(scheme.Scheme); err != nil {
		panic(err)
	}
}

func (c *Client) newStatusWatcher() (*statusWaiter, error) {
	cfg, err := c.Factory.ToRESTConfig()
	if err != nil {
		return nil, err
	}
	dynamicClient, err := c.Factory.DynamicClient()
	if err != nil {
		return nil, err
	}
	httpClient, err := rest.HTTPClientFor(cfg)
	if err != nil {
		return nil, err
	}
	restMapper, err := apiutil.NewDynamicRESTMapper(cfg, httpClient)
	if err != nil {
		return nil, err
	}
	return &statusWaiter{
		restMapper: restMapper,
		client:     dynamicClient,
	}, nil
}

func (c *Client) GetWaiter(strategy WaitStrategy) (Waiter, error) {
	switch strategy {
	case LegacyStrategy:
		kc, err := c.Factory.KubernetesClientSet()
		if err != nil {
			return nil, err
		}
		return &legacyWaiter{kubeClient: kc}, nil
	case StatusWatcherStrategy:
		return c.newStatusWatcher()
	case HookOnlyStrategy:
		sw, err := c.newStatusWatcher()
		if err != nil {
			return nil, err
		}
		return &hookOnlyWaiter{sw: sw}, nil
	default:
		return nil, errors.New("unknown wait strategy")
	}
}

func (c *Client) SetWaiter(ws WaitStrategy) error {
	var err error
	c.Waiter, err = c.GetWaiter(ws)
	if err != nil {
		return err
	}
	return nil
}

// New creates a new Client.
func New(getter genericclioptions.RESTClientGetter) *Client {
	if getter == nil {
		getter = genericclioptions.NewConfigFlags(true)
	}
	factory := cmdutil.NewFactory(getter)
	c := &Client{
		Factory: factory,
	}
	return c
}

// getKubeClient get or create a new KubernetesClientSet
func (c *Client) getKubeClient() (kubernetes.Interface, error) {
	var err error
	if c.kubeClient == nil {
		c.kubeClient, err = c.Factory.KubernetesClientSet()
	}

	return c.kubeClient, err
}

// IsReachable tests connectivity to the cluster.
func (c *Client) IsReachable() error {
	client, err := c.getKubeClient()
	if err == genericclioptions.ErrEmptyConfig {
		// re-replace kubernetes ErrEmptyConfig error with a friendly error
		// moar workarounds for Kubernetes API breaking.
		return errors.New("Kubernetes cluster unreachable")
	}
	if err != nil {
		return errors.Wrap(err, "Kubernetes cluster unreachable")
	}
	if _, err := client.Discovery().ServerVersion(); err != nil {
		return errors.Wrap(err, "Kubernetes cluster unreachable")
	}
	return nil
}

// Create creates Kubernetes resources specified in the resource list.
func (c *Client) Create(resources ResourceList) (*Result, error) {
	slog.Debug("creating resource(s)", "resources", len(resources))
	if err := perform(resources, createResource); err != nil {
		return nil, err
	}
	return &Result{Created: resources}, nil
}

func transformRequests(req *rest.Request) {
	tableParam := strings.Join([]string{
		fmt.Sprintf("application/json;as=Table;v=%s;g=%s", metav1.SchemeGroupVersion.Version, metav1.GroupName),
		fmt.Sprintf("application/json;as=Table;v=%s;g=%s", metav1beta1.SchemeGroupVersion.Version, metav1beta1.GroupName),
		"application/json",
	}, ",")
	req.SetHeader("Accept", tableParam)

	// if sorting, ensure we receive the full object in order to introspect its fields via jsonpath
	req.Param("includeObject", "Object")
}

// Get retrieves the resource objects supplied. If related is set to true the
// related pods are fetched as well. If the passed in resources are a table kind
// the related resources will also be fetched as kind=table.
func (c *Client) Get(resources ResourceList, related bool) (map[string][]runtime.Object, error) {
	buf := new(bytes.Buffer)
	objs := make(map[string][]runtime.Object)

	podSelectors := []map[string]string{}
	err := resources.Visit(func(info *resource.Info, err error) error {
		if err != nil {
			return err
		}

		gvk := info.ResourceMapping().GroupVersionKind
		vk := gvk.Version + "/" + gvk.Kind
		obj, err := getResource(info)
		if err != nil {
			fmt.Fprintf(buf, "Get resource %s failed, err:%v\n", info.Name, err)
		} else {
			objs[vk] = append(objs[vk], obj)

			// Only fetch related pods if they are requested
			if related {
				// Discover if the existing object is a table. If it is, request
				// the pods as Tables. Otherwise request them normally.
				objGVK := obj.GetObjectKind().GroupVersionKind()
				var isTable bool
				if objGVK.Kind == "Table" {
					isTable = true
				}

				objs, err = c.getSelectRelationPod(info, objs, isTable, &podSelectors)
				if err != nil {
					slog.Warn("get the relation pod is failed", slog.Any("error", err))
				}
			}
		}

		return nil
	})
	if err != nil {
		return nil, err
	}

	return objs, nil
}

func (c *Client) getSelectRelationPod(info *resource.Info, objs map[string][]runtime.Object, table bool, podSelectors *[]map[string]string) (map[string][]runtime.Object, error) {
	if info == nil {
		return objs, nil
	}
	slog.Debug("get relation pod of object", "namespace", info.Namespace, "name", info.Name, "kind", info.Mapping.GroupVersionKind.Kind)
	selector, ok, _ := getSelectorFromObject(info.Object)
	if !ok {
		return objs, nil
	}

	for index := range *podSelectors {
		if reflect.DeepEqual((*podSelectors)[index], selector) {
			// check if pods for selectors are already added. This avoids duplicate printing of pods
			return objs, nil
		}
	}

	*podSelectors = append(*podSelectors, selector)

	var infos []*resource.Info
	var err error
	if table {
		infos, err = c.Factory.NewBuilder().
			Unstructured().
			ContinueOnError().
			NamespaceParam(info.Namespace).
			DefaultNamespace().
			ResourceTypes("pods").
			LabelSelector(labels.Set(selector).AsSelector().String()).
			TransformRequests(transformRequests).
			Do().Infos()
		if err != nil {
			return objs, err
		}
	} else {
		infos, err = c.Factory.NewBuilder().
			Unstructured().
			ContinueOnError().
			NamespaceParam(info.Namespace).
			DefaultNamespace().
			ResourceTypes("pods").
			LabelSelector(labels.Set(selector).AsSelector().String()).
			Do().Infos()
		if err != nil {
			return objs, err
		}
	}
	vk := "v1/Pod(related)"

	for _, info := range infos {
		objs[vk] = append(objs[vk], info.Object)
	}
	return objs, nil
}

func getSelectorFromObject(obj runtime.Object) (map[string]string, bool, error) {
	typed := obj.(*unstructured.Unstructured)
	kind := typed.Object["kind"]
	switch kind {
	case "ReplicaSet", "Deployment", "StatefulSet", "DaemonSet", "Job":
		return unstructured.NestedStringMap(typed.Object, "spec", "selector", "matchLabels")
	case "ReplicationController":
		return unstructured.NestedStringMap(typed.Object, "spec", "selector")
	default:
		return nil, false, nil
	}
}

func getResource(info *resource.Info) (runtime.Object, error) {
	obj, err := resource.NewHelper(info.Client, info.Mapping).Get(info.Namespace, info.Name)
	if err != nil {
		return nil, err
	}
	return obj, nil
}

func (c *Client) namespace() string {
	if c.Namespace != "" {
		return c.Namespace
	}
	if ns, _, err := c.Factory.ToRawKubeConfigLoader().Namespace(); err == nil {
		return ns
	}
	return v1.NamespaceDefault
}

// newBuilder returns a new resource builder for structured api objects.
func (c *Client) newBuilder() *resource.Builder {
	return c.Factory.NewBuilder().
		ContinueOnError().
		NamespaceParam(c.namespace()).
		DefaultNamespace().
		Flatten()
}

// Build validates for Kubernetes objects and returns unstructured infos.
func (c *Client) Build(reader io.Reader, validate bool) (ResourceList, error) {
	validationDirective := metav1.FieldValidationIgnore
	if validate {
		validationDirective = metav1.FieldValidationStrict
	}

	schema, err := c.Factory.Validator(validationDirective)
	if err != nil {
		return nil, err
	}
	result, err := c.newBuilder().
		Unstructured().
		Schema(schema).
		Stream(reader, "").
		Do().Infos()
	return result, scrubValidationError(err)
}

// BuildTable validates for Kubernetes objects and returns unstructured infos.
// The returned kind is a Table.
func (c *Client) BuildTable(reader io.Reader, validate bool) (ResourceList, error) {
	validationDirective := metav1.FieldValidationIgnore
	if validate {
		validationDirective = metav1.FieldValidationStrict
	}

	schema, err := c.Factory.Validator(validationDirective)
	if err != nil {
		return nil, err
	}
	result, err := c.newBuilder().
		Unstructured().
		Schema(schema).
		Stream(reader, "").
		TransformRequests(transformRequests).
		Do().Infos()
	return result, scrubValidationError(err)
}

// Update takes the current list of objects and target list of objects and
// creates resources that don't already exist, updates resources that have been
// modified in the target configuration, and deletes resources from the current
// configuration that are not present in the target configuration. If an error
// occurs, a Result will still be returned with the error, containing all
// resource updates, creations, and deletions that were attempted. These can be
// used for cleanup or other logging purposes.
func (c *Client) Update(original, target ResourceList, force bool) (*Result, error) {
	updateErrors := []string{}
	res := &Result{}

	slog.Debug("checking resources for changes", "resources", len(target))
	err := target.Visit(func(info *resource.Info, err error) error {
		if err != nil {
			return err
		}

		helper := resource.NewHelper(info.Client, info.Mapping).WithFieldManager(getManagedFieldsManager())
		if _, err := helper.Get(info.Namespace, info.Name); err != nil {
			if !apierrors.IsNotFound(err) {
				return errors.Wrap(err, "could not get information about the resource")
			}

			// Append the created resource to the results, even if something fails
			res.Created = append(res.Created, info)

			// Since the resource does not exist, create it.
			if err := createResource(info); err != nil {
				return errors.Wrap(err, "failed to create resource")
			}

			kind := info.Mapping.GroupVersionKind.Kind
			slog.Debug("created a new resource", "namespace", info.Namespace, "name", info.Name, "kind", kind)
			return nil
		}

		originalInfo := original.Get(info)
		if originalInfo == nil {
			kind := info.Mapping.GroupVersionKind.Kind
			return errors.Errorf("no %s with the name %q found", kind, info.Name)
		}

		if err := updateResource(c, info, originalInfo.Object, force); err != nil {
			slog.Debug("error updating the resource", "namespace", info.Namespace, "name", info.Name, "kind", info.Mapping.GroupVersionKind.Kind, slog.Any("error", err))
			updateErrors = append(updateErrors, err.Error())
		}
		// Because we check for errors later, append the info regardless
		res.Updated = append(res.Updated, info)

		return nil
	})

	switch {
	case err != nil:
		return res, err
	case len(updateErrors) != 0:
		return res, errors.New(strings.Join(updateErrors, " && "))
	}

	for _, info := range original.Difference(target) {
		slog.Debug("deleting resource", "namespace", info.Namespace, "name", info.Name, "kind", info.Mapping.GroupVersionKind.Kind)

		if err := info.Get(); err != nil {
			slog.Debug("unable to get object", "namespace", info.Namespace, "name", info.Name, "kind", info.Mapping.GroupVersionKind.Kind, slog.Any("error", err))
			continue
		}
		annotations, err := metadataAccessor.Annotations(info.Object)
		if err != nil {
			slog.Debug("unable to get annotations", "namespace", info.Namespace, "name", info.Name, "kind", info.Mapping.GroupVersionKind.Kind, slog.Any("error", err))
		}
		if annotations != nil && annotations[ResourcePolicyAnno] == KeepPolicy {
			slog.Debug("skipping delete due to annotation", "namespace", info.Namespace, "name", info.Name, "kind", info.Mapping.GroupVersionKind.Kind, "annotation", ResourcePolicyAnno, "value", KeepPolicy)
			continue
		}
		if err := deleteResource(info, metav1.DeletePropagationBackground); err != nil {
			slog.Debug("failed to delete resource", "namespace", info.Namespace, "name", info.Name, "kind", info.Mapping.GroupVersionKind.Kind, slog.Any("error", err))
			continue
		}
		res.Deleted = append(res.Deleted, info)
	}
	return res, nil
}

// Delete deletes Kubernetes resources specified in the resources list with
// background cascade deletion. It will attempt to delete all resources even
// if one or more fail and collect any errors. All successfully deleted items
// will be returned in the `Deleted` ResourceList that is part of the result.
func (c *Client) Delete(resources ResourceList) (*Result, []error) {
	return rdelete(c, resources, metav1.DeletePropagationBackground)
}

// Delete deletes Kubernetes resources specified in the resources list with
// given deletion propagation policy. It will attempt to delete all resources even
// if one or more fail and collect any errors. All successfully deleted items
// will be returned in the `Deleted` ResourceList that is part of the result.
func (c *Client) DeleteWithPropagationPolicy(resources ResourceList, policy metav1.DeletionPropagation) (*Result, []error) {
	return rdelete(c, resources, policy)
}

func rdelete(_ *Client, resources ResourceList, propagation metav1.DeletionPropagation) (*Result, []error) {
	var errs []error
	res := &Result{}
	mtx := sync.Mutex{}
	err := perform(resources, func(info *resource.Info) error {
		slog.Debug("starting delete resource", "namespace", info.Namespace, "name", info.Name, "kind", info.Mapping.GroupVersionKind.Kind)
		err := deleteResource(info, propagation)
		if err == nil || apierrors.IsNotFound(err) {
			if err != nil {
				slog.Debug("ignoring delete failure", "namespace", info.Namespace, "name", info.Name, "kind", info.Mapping.GroupVersionKind.Kind, slog.Any("error", err))
			}
			mtx.Lock()
			defer mtx.Unlock()
			res.Deleted = append(res.Deleted, info)
			return nil
		}
		mtx.Lock()
		defer mtx.Unlock()
		// Collect the error and continue on
		errs = append(errs, err)
		return nil
	})
	if err != nil {
		if errors.Is(err, ErrNoObjectsVisited) {
			err = fmt.Errorf("object not found, skipping delete: %w", err)
		}
		errs = append(errs, err)
	}
	if errs != nil {
		return nil, errs
	}
	return res, nil
}

// getManagedFieldsManager returns the manager string. If one was set it will be returned.
// Otherwise, one is calculated based on the name of the binary.
func getManagedFieldsManager() string {

	// When a manager is explicitly set use it
	if ManagedFieldsManager != "" {
		return ManagedFieldsManager
	}

	// When no manager is set and no calling application can be found it is unknown
	if len(os.Args[0]) == 0 {
		return "unknown"
	}

	// When there is an application that can be determined and no set manager
	// use the base name. This is one of the ways Kubernetes libs handle figuring
	// names out.
	return filepath.Base(os.Args[0])
}

func batchPerform(infos ResourceList, fn func(*resource.Info) error, errs chan<- error) {
	var kind string
	var wg sync.WaitGroup
	for _, info := range infos {
		currentKind := info.Object.GetObjectKind().GroupVersionKind().Kind
		if kind != currentKind {
			wg.Wait()
			kind = currentKind
		}
		wg.Add(1)
		go func(i *resource.Info) {
			errs <- fn(i)
			wg.Done()
		}(info)
	}
}

func createResource(info *resource.Info) error {
	return retry.RetryOnConflict(
		retry.DefaultRetry,
		func() error {
			obj, err := resource.NewHelper(info.Client, info.Mapping).WithFieldManager(getManagedFieldsManager()).Create(info.Namespace, true, info.Object)
			if err != nil {
				return err
			}
			return info.Refresh(obj, true)
		})
}

func deleteResource(info *resource.Info, policy metav1.DeletionPropagation) error {
	return retry.RetryOnConflict(
		retry.DefaultRetry,
		func() error {
			opts := &metav1.DeleteOptions{PropagationPolicy: &policy}
			_, err := resource.NewHelper(info.Client, info.Mapping).WithFieldManager(getManagedFieldsManager()).DeleteWithOptions(info.Namespace, info.Name, opts)
			return err
		})
}

func createPatch(target *resource.Info, current runtime.Object) ([]byte, types.PatchType, error) {
	oldData, err := json.Marshal(current)
	if err != nil {
		return nil, types.StrategicMergePatchType, errors.Wrap(err, "serializing current configuration")
	}
	newData, err := json.Marshal(target.Object)
	if err != nil {
		return nil, types.StrategicMergePatchType, errors.Wrap(err, "serializing target configuration")
	}

	// Fetch the current object for the three way merge
	helper := resource.NewHelper(target.Client, target.Mapping).WithFieldManager(getManagedFieldsManager())
	currentObj, err := helper.Get(target.Namespace, target.Name)
	if err != nil && !apierrors.IsNotFound(err) {
		return nil, types.StrategicMergePatchType, errors.Wrapf(err, "unable to get data for current object %s/%s", target.Namespace, target.Name)
	}

	// Even if currentObj is nil (because it was not found), it will marshal just fine
	currentData, err := json.Marshal(currentObj)
	if err != nil {
		return nil, types.StrategicMergePatchType, errors.Wrap(err, "serializing live configuration")
	}

	// Get a versioned object
	versionedObject := AsVersioned(target)

	// Unstructured objects, such as CRDs, may not have a not registered error
	// returned from ConvertToVersion. Anything that's unstructured should
	// use the jsonpatch.CreateMergePatch. Strategic Merge Patch is not supported
	// on objects like CRDs.
	_, isUnstructured := versionedObject.(runtime.Unstructured)

	// On newer K8s versions, CRDs aren't unstructured but has this dedicated type
	_, isCRD := versionedObject.(*apiextv1beta1.CustomResourceDefinition)

	if isUnstructured || isCRD {
		// fall back to generic JSON merge patch
		patch, err := jsonpatch.CreateMergePatch(oldData, newData)
		return patch, types.MergePatchType, err
	}

	patchMeta, err := strategicpatch.NewPatchMetaFromStruct(versionedObject)
	if err != nil {
		return nil, types.StrategicMergePatchType, errors.Wrap(err, "unable to create patch metadata from object")
	}

	patch, err := strategicpatch.CreateThreeWayMergePatch(oldData, newData, currentData, patchMeta, true)
	return patch, types.StrategicMergePatchType, err
}

func updateResource(_ *Client, target *resource.Info, currentObj runtime.Object, force bool) error {
	var (
		obj    runtime.Object
		helper = resource.NewHelper(target.Client, target.Mapping).WithFieldManager(getManagedFieldsManager())
		kind   = target.Mapping.GroupVersionKind.Kind
	)

	// if --force is applied, attempt to replace the existing resource with the new object.
	if force {
		var err error
		obj, err = helper.Replace(target.Namespace, target.Name, true, target.Object)
		if err != nil {
			return errors.Wrap(err, "failed to replace object")
		}
		slog.Debug("replace succeeded", "name", target.Name, "initialKind", currentObj.GetObjectKind().GroupVersionKind().Kind, "kind", kind)
	} else {
		patch, patchType, err := createPatch(target, currentObj)
		if err != nil {
			return errors.Wrap(err, "failed to create patch")
		}

		if patch == nil || string(patch) == "{}" {
			slog.Debug("no changes detected", "kind", kind, "name", target.Name)
			// This needs to happen to make sure that Helm has the latest info from the API
			// Otherwise there will be no labels and other functions that use labels will panic
			if err := target.Get(); err != nil {
				return errors.Wrap(err, "failed to refresh resource information")
			}
			return nil
		}
		// send patch to server
		slog.Debug("patching resource", "kind", kind, "name", target.Name, "namespace", target.Namespace)
		obj, err = helper.Patch(target.Namespace, target.Name, patchType, patch, nil)
		if err != nil {
			return errors.Wrapf(err, "cannot patch %q with kind %s", target.Name, kind)
		}
	}

	target.Refresh(obj, true)
	return nil
}

// GetPodList uses the kubernetes interface to get the list of pods filtered by listOptions
func (c *Client) GetPodList(namespace string, listOptions metav1.ListOptions) (*v1.PodList, error) {
	podList, err := c.kubeClient.CoreV1().Pods(namespace).List(context.Background(), listOptions)
	if err != nil {
		return nil, fmt.Errorf("failed to get pod list with options: %+v with error: %v", listOptions, err)
	}
	return podList, nil
}

// OutputContainerLogsForPodList is a helper that outputs logs for a list of pods
func (c *Client) OutputContainerLogsForPodList(podList *v1.PodList, namespace string, writerFunc func(namespace, pod, container string) io.Writer) error {
	for _, pod := range podList.Items {
		for _, container := range pod.Spec.Containers {
			options := &v1.PodLogOptions{
				Container: container.Name,
			}
			request := c.kubeClient.CoreV1().Pods(namespace).GetLogs(pod.Name, options)
			err2 := copyRequestStreamToWriter(request, pod.Name, container.Name, writerFunc(namespace, pod.Name, container.Name))
			if err2 != nil {
				return err2
			}
		}
	}
	return nil
}

func copyRequestStreamToWriter(request *rest.Request, podName, containerName string, writer io.Writer) error {
	readCloser, err := request.Stream(context.Background())
	if err != nil {
		return errors.Errorf("Failed to stream pod logs for pod: %s, container: %s", podName, containerName)
	}
	defer readCloser.Close()
	_, err = io.Copy(writer, readCloser)
	if err != nil {
		return errors.Errorf("Failed to copy IO from logs for pod: %s, container: %s", podName, containerName)
	}
	return nil
}

// scrubValidationError removes kubectl info from the message.
func scrubValidationError(err error) error {
	if err == nil {
		return nil
	}
	const stopValidateMessage = "if you choose to ignore these errors, turn validation off with --validate=false"

	if strings.Contains(err.Error(), stopValidateMessage) {
		return errors.New(strings.ReplaceAll(err.Error(), "; "+stopValidateMessage, ""))
	}
	return err
}