traefik/pkg/provider/kubernetes/gateway/client.go
2021-03-04 20:08:03 +01:00

443 lines
14 KiB
Go

package gateway
import (
"context"
"errors"
"fmt"
"os"
"time"
"github.com/traefik/traefik/v2/pkg/log"
corev1 "k8s.io/api/core/v1"
kubeerror "k8s.io/apimachinery/pkg/api/errors"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/labels"
"k8s.io/client-go/informers"
"k8s.io/client-go/kubernetes"
"k8s.io/client-go/rest"
"k8s.io/client-go/tools/clientcmd"
"sigs.k8s.io/service-apis/apis/v1alpha1"
"sigs.k8s.io/service-apis/pkg/client/clientset/versioned"
"sigs.k8s.io/service-apis/pkg/client/informers/externalversions"
)
const resyncPeriod = 10 * time.Minute
type resourceEventHandler struct {
ev chan<- interface{}
}
func (reh *resourceEventHandler) OnAdd(obj interface{}) {
eventHandlerFunc(reh.ev, obj)
}
func (reh *resourceEventHandler) OnUpdate(oldObj, newObj interface{}) {
switch oldObj.(type) {
case *v1alpha1.GatewayClass:
// Skip update for gateway classes. We only manage addition or deletion for this cluster-wide resource.
return
default:
eventHandlerFunc(reh.ev, newObj)
}
}
func (reh *resourceEventHandler) OnDelete(obj interface{}) {
eventHandlerFunc(reh.ev, obj)
}
// Client is a client for the Provider master.
// WatchAll starts the watch of the Provider resources and updates the stores.
// The stores can then be accessed via the Get* functions.
type Client interface {
WatchAll(namespaces []string, stopCh <-chan struct{}) (<-chan interface{}, error)
GetGatewayClasses() ([]*v1alpha1.GatewayClass, error)
UpdateGatewayStatus(gateway *v1alpha1.Gateway, gatewayStatus v1alpha1.GatewayStatus) error
UpdateGatewayClassStatus(gatewayClass *v1alpha1.GatewayClass, condition metav1.Condition) error
GetGateways() []*v1alpha1.Gateway
GetHTTPRoutes(namespace string, selector labels.Selector) ([]*v1alpha1.HTTPRoute, error)
GetService(namespace, name string) (*corev1.Service, bool, error)
GetSecret(namespace, name string) (*corev1.Secret, bool, error)
GetEndpoints(namespace, name string) (*corev1.Endpoints, bool, error)
}
type clientWrapper struct {
csGateway versioned.Interface
csKube kubernetes.Interface
factoryGatewayClass externalversions.SharedInformerFactory
factoriesGateway map[string]externalversions.SharedInformerFactory
factoriesKube map[string]informers.SharedInformerFactory
factoriesSecret map[string]informers.SharedInformerFactory
isNamespaceAll bool
watchedNamespaces []string
labelSelector string
}
func createClientFromConfig(c *rest.Config) (*clientWrapper, error) {
csGateway, err := versioned.NewForConfig(c)
if err != nil {
return nil, err
}
csKube, err := kubernetes.NewForConfig(c)
if err != nil {
return nil, err
}
return newClientImpl(csKube, csGateway), nil
}
func newClientImpl(csKube kubernetes.Interface, csGateway versioned.Interface) *clientWrapper {
return &clientWrapper{
csGateway: csGateway,
csKube: csKube,
factoriesGateway: make(map[string]externalversions.SharedInformerFactory),
factoriesKube: make(map[string]informers.SharedInformerFactory),
factoriesSecret: make(map[string]informers.SharedInformerFactory),
}
}
// newInClusterClient returns a new Provider client that is expected to run
// inside the cluster.
func newInClusterClient(endpoint string) (*clientWrapper, error) {
config, err := rest.InClusterConfig()
if err != nil {
return nil, fmt.Errorf("failed to create in-cluster configuration: %w", err)
}
if endpoint != "" {
config.Host = endpoint
}
return createClientFromConfig(config)
}
func newExternalClusterClientFromFile(file string) (*clientWrapper, error) {
configFromFlags, err := clientcmd.BuildConfigFromFlags("", file)
if err != nil {
return nil, err
}
return createClientFromConfig(configFromFlags)
}
// newExternalClusterClient returns a new Provider client that may run outside
// of the cluster.
// The endpoint parameter must not be empty.
func newExternalClusterClient(endpoint, token, caFilePath string) (*clientWrapper, error) {
if endpoint == "" {
return nil, errors.New("endpoint missing for external cluster client")
}
config := &rest.Config{
Host: endpoint,
BearerToken: token,
}
if caFilePath != "" {
caData, err := os.ReadFile(caFilePath)
if err != nil {
return nil, fmt.Errorf("failed to read CA file %s: %w", caFilePath, err)
}
config.TLSClientConfig = rest.TLSClientConfig{CAData: caData}
}
return createClientFromConfig(config)
}
// WatchAll starts namespace-specific controllers for all relevant kinds.
func (c *clientWrapper) WatchAll(namespaces []string, stopCh <-chan struct{}) (<-chan interface{}, error) {
eventCh := make(chan interface{}, 1)
eventHandler := &resourceEventHandler{ev: eventCh}
if len(namespaces) == 0 {
namespaces = []string{metav1.NamespaceAll}
c.isNamespaceAll = true
}
c.watchedNamespaces = namespaces
notOwnedByHelm := func(opts *metav1.ListOptions) {
opts.LabelSelector = "owner!=helm"
}
labelSelectorOptions := func(options *metav1.ListOptions) {
options.LabelSelector = c.labelSelector
}
c.factoryGatewayClass = externalversions.NewSharedInformerFactoryWithOptions(c.csGateway, resyncPeriod, externalversions.WithTweakListOptions(labelSelectorOptions))
c.factoryGatewayClass.Networking().V1alpha1().GatewayClasses().Informer().AddEventHandler(eventHandler)
for _, ns := range namespaces {
factoryGateway := externalversions.NewSharedInformerFactoryWithOptions(c.csGateway, resyncPeriod, externalversions.WithNamespace(ns))
factoryGateway.Networking().V1alpha1().Gateways().Informer().AddEventHandler(eventHandler)
factoryGateway.Networking().V1alpha1().HTTPRoutes().Informer().AddEventHandler(eventHandler)
factoryKube := informers.NewSharedInformerFactoryWithOptions(c.csKube, resyncPeriod, informers.WithNamespace(ns))
factoryKube.Core().V1().Services().Informer().AddEventHandler(eventHandler)
factoryKube.Core().V1().Endpoints().Informer().AddEventHandler(eventHandler)
factorySecret := informers.NewSharedInformerFactoryWithOptions(c.csKube, resyncPeriod, informers.WithNamespace(ns), informers.WithTweakListOptions(notOwnedByHelm))
factorySecret.Core().V1().Secrets().Informer().AddEventHandler(eventHandler)
c.factoriesGateway[ns] = factoryGateway
c.factoriesKube[ns] = factoryKube
c.factoriesSecret[ns] = factorySecret
}
c.factoryGatewayClass.Start(stopCh)
for _, ns := range namespaces {
c.factoriesGateway[ns].Start(stopCh)
c.factoriesKube[ns].Start(stopCh)
c.factoriesSecret[ns].Start(stopCh)
}
for t, ok := range c.factoryGatewayClass.WaitForCacheSync(stopCh) {
if !ok {
return nil, fmt.Errorf("timed out waiting for controller caches to sync %s", t.String())
}
}
for _, ns := range namespaces {
for t, ok := range c.factoriesGateway[ns].WaitForCacheSync(stopCh) {
if !ok {
return nil, fmt.Errorf("timed out waiting for controller caches to sync %s in namespace %q", t.String(), ns)
}
}
for t, ok := range c.factoriesKube[ns].WaitForCacheSync(stopCh) {
if !ok {
return nil, fmt.Errorf("timed out waiting for controller caches to sync %s in namespace %q", t.String(), ns)
}
}
for t, ok := range c.factoriesSecret[ns].WaitForCacheSync(stopCh) {
if !ok {
return nil, fmt.Errorf("timed out waiting for controller caches to sync %s in namespace %q", t.String(), ns)
}
}
}
return eventCh, nil
}
func (c *clientWrapper) GetHTTPRoutes(namespace string, selector labels.Selector) ([]*v1alpha1.HTTPRoute, error) {
if !c.isWatchedNamespace(namespace) {
return nil, fmt.Errorf("failed to get HTTPRoute %s with labels selector %s: namespace is not within watched namespaces", namespace, selector)
}
httpRoutes, err := c.factoriesGateway[c.lookupNamespace(namespace)].Networking().V1alpha1().HTTPRoutes().Lister().HTTPRoutes(namespace).List(selector)
if err != nil {
return nil, err
}
if len(httpRoutes) == 0 {
return nil, fmt.Errorf("failed to get HTTPRoute %s with labels selector %s: namespace is not within watched namespaces", namespace, selector)
}
return httpRoutes, nil
}
func (c *clientWrapper) GetGateways() []*v1alpha1.Gateway {
var result []*v1alpha1.Gateway
for ns, factory := range c.factoriesGateway {
gateways, err := factory.Networking().V1alpha1().Gateways().Lister().List(labels.Everything())
if err != nil {
log.WithoutContext().Errorf("Failed to list Gateways in namespace %s: %v", ns, err)
continue
}
result = append(result, gateways...)
}
return result
}
func (c *clientWrapper) GetGatewayClasses() ([]*v1alpha1.GatewayClass, error) {
return c.factoryGatewayClass.Networking().V1alpha1().GatewayClasses().Lister().List(labels.Everything())
}
func (c *clientWrapper) UpdateGatewayClassStatus(gatewayClass *v1alpha1.GatewayClass, condition metav1.Condition) error {
gc := gatewayClass.DeepCopy()
var newConditions []metav1.Condition
for _, cond := range gc.Status.Conditions {
// No update for identical condition.
if cond.Type == condition.Type && cond.Status == condition.Status {
return nil
}
// Keep other condition types.
if cond.Type != condition.Type {
newConditions = append(newConditions, cond)
}
}
// Append the condition to update.
newConditions = append(newConditions, condition)
gc.Status.Conditions = newConditions
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()
_, err := c.csGateway.NetworkingV1alpha1().GatewayClasses().UpdateStatus(ctx, gc, metav1.UpdateOptions{})
if err != nil {
return fmt.Errorf("failed to update GatewayClass %q status: %w", gatewayClass.Name, err)
}
return nil
}
func (c *clientWrapper) UpdateGatewayStatus(gateway *v1alpha1.Gateway, gatewayStatus v1alpha1.GatewayStatus) error {
if !c.isWatchedNamespace(gateway.Namespace) {
return fmt.Errorf("cannot update Gateway status %s/%s: namespace is not within watched namespaces", gateway.Namespace, gateway.Name)
}
if statusEquals(gateway.Status, gatewayStatus) {
return nil
}
g := gateway.DeepCopy()
g.Status = gatewayStatus
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()
_, err := c.csGateway.NetworkingV1alpha1().Gateways(gateway.Namespace).UpdateStatus(ctx, g, metav1.UpdateOptions{})
if err != nil {
return fmt.Errorf("failed to update Gateway %q status: %w", gateway.Name, err)
}
return nil
}
func statusEquals(oldStatus, newStatus v1alpha1.GatewayStatus) bool {
if len(oldStatus.Listeners) != len(newStatus.Listeners) {
return false
}
if !conditionsEquals(oldStatus.Conditions, newStatus.Conditions) {
return false
}
listenerMatches := 0
for _, newListener := range newStatus.Listeners {
for _, oldListener := range oldStatus.Listeners {
if newListener.Port == oldListener.Port {
if !conditionsEquals(newListener.Conditions, oldListener.Conditions) {
return false
}
listenerMatches++
}
}
}
return listenerMatches == len(oldStatus.Listeners)
}
func conditionsEquals(conditionsA, conditionsB []metav1.Condition) bool {
if len(conditionsA) != len(conditionsB) {
return false
}
conditionMatches := 0
for _, conditionA := range conditionsA {
for _, conditionB := range conditionsB {
if conditionA.Type == conditionB.Type {
if conditionA.Reason != conditionB.Reason || conditionA.Status != conditionB.Status || conditionA.Message != conditionB.Message {
return false
}
conditionMatches++
}
}
}
return conditionMatches == len(conditionsA)
}
// GetService returns the named service from the given namespace.
func (c *clientWrapper) GetService(namespace, name string) (*corev1.Service, bool, error) {
if !c.isWatchedNamespace(namespace) {
return nil, false, fmt.Errorf("failed to get service %s/%s: namespace is not within watched namespaces", namespace, name)
}
service, err := c.factoriesKube[c.lookupNamespace(namespace)].Core().V1().Services().Lister().Services(namespace).Get(name)
exist, err := translateNotFoundError(err)
return service, exist, err
}
// GetEndpoints returns the named endpoints from the given namespace.
func (c *clientWrapper) GetEndpoints(namespace, name string) (*corev1.Endpoints, bool, error) {
if !c.isWatchedNamespace(namespace) {
return nil, false, fmt.Errorf("failed to get endpoints %s/%s: namespace is not within watched namespaces", namespace, name)
}
endpoint, err := c.factoriesKube[c.lookupNamespace(namespace)].Core().V1().Endpoints().Lister().Endpoints(namespace).Get(name)
exist, err := translateNotFoundError(err)
return endpoint, exist, err
}
// GetSecret returns the named secret from the given namespace.
func (c *clientWrapper) GetSecret(namespace, name string) (*corev1.Secret, bool, error) {
if !c.isWatchedNamespace(namespace) {
return nil, false, fmt.Errorf("failed to get secret %s/%s: namespace is not within watched namespaces", namespace, name)
}
secret, err := c.factoriesSecret[c.lookupNamespace(namespace)].Core().V1().Secrets().Lister().Secrets(namespace).Get(name)
exist, err := translateNotFoundError(err)
return secret, exist, err
}
// lookupNamespace returns the lookup namespace key for the given namespace.
// When listening on all namespaces, it returns the client-go identifier ("")
// for all-namespaces. Otherwise, it returns the given namespace.
// The distinction is necessary because we index all informers on the special
// identifier iff all-namespaces are requested but receive specific namespace
// identifiers from the Kubernetes API, so we have to bridge this gap.
func (c *clientWrapper) lookupNamespace(ns string) string {
if c.isNamespaceAll {
return metav1.NamespaceAll
}
return ns
}
// eventHandlerFunc will pass the obj on to the events channel or drop it.
// This is so passing the events along won't block in the case of high volume.
// The events are only used for signaling anyway so dropping a few is ok.
func eventHandlerFunc(events chan<- interface{}, obj interface{}) {
select {
case events <- obj:
default:
}
}
// translateNotFoundError will translate a "not found" error to a boolean return
// value which indicates if the resource exists and a nil error.
func translateNotFoundError(err error) (bool, error) {
if kubeerror.IsNotFound(err) {
return false, nil
}
return err == nil, err
}
// isWatchedNamespace checks to ensure that the namespace is being watched before we request
// it to ensure we don't panic by requesting an out-of-watch object.
func (c *clientWrapper) isWatchedNamespace(ns string) bool {
if c.isNamespaceAll {
return true
}
for _, watchedNamespace := range c.watchedNamespaces {
if watchedNamespace == ns {
return true
}
}
return false
}