traefik/pkg/provider/kubernetes/ingress/client.go
2021-04-29 16:20:03 +02:00

546 lines
18 KiB
Go

package ingress
import (
"context"
"errors"
"fmt"
"os"
"path/filepath"
"runtime"
"time"
"github.com/hashicorp/go-version"
"github.com/traefik/traefik/v2/pkg/log"
"github.com/traefik/traefik/v2/pkg/provider/kubernetes/k8s"
traefikversion "github.com/traefik/traefik/v2/pkg/version"
corev1 "k8s.io/api/core/v1"
networkingv1 "k8s.io/api/networking/v1"
networkingv1beta1 "k8s.io/api/networking/v1beta1"
kubeerror "k8s.io/apimachinery/pkg/api/errors"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/labels"
"k8s.io/apimachinery/pkg/util/intstr"
"k8s.io/client-go/informers"
"k8s.io/client-go/kubernetes"
"k8s.io/client-go/rest"
"k8s.io/client-go/tools/clientcmd"
)
const (
resyncPeriod = 10 * time.Minute
defaultTimeout = 5 * time.Second
)
type marshaler interface {
Marshal() ([]byte, error)
}
// 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)
GetIngresses() []*networkingv1.Ingress
GetIngressClasses() ([]*networkingv1beta1.IngressClass, 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)
UpdateIngressStatus(ing *networkingv1.Ingress, ingStatus []corev1.LoadBalancerIngress) error
GetServerVersion() (*version.Version, error)
}
type clientWrapper struct {
clientset kubernetes.Interface
factoriesKube map[string]informers.SharedInformerFactory
factoriesSecret map[string]informers.SharedInformerFactory
factoriesIngress map[string]informers.SharedInformerFactory
clusterFactory informers.SharedInformerFactory
ingressLabelSelector string
isNamespaceAll bool
watchedNamespaces []string
}
// 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)
}
func createClientFromConfig(c *rest.Config) (*clientWrapper, error) {
c.UserAgent = fmt.Sprintf(
"%s/%s (%s/%s) kubernetes/ingress",
filepath.Base(os.Args[0]),
traefikversion.Version,
runtime.GOOS,
runtime.GOARCH,
)
clientset, err := kubernetes.NewForConfig(c)
if err != nil {
return nil, err
}
return newClientImpl(clientset), nil
}
func newClientImpl(clientset kubernetes.Interface) *clientWrapper {
return &clientWrapper{
clientset: clientset,
factoriesSecret: make(map[string]informers.SharedInformerFactory),
factoriesIngress: make(map[string]informers.SharedInformerFactory),
factoriesKube: make(map[string]informers.SharedInformerFactory),
}
}
// 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 := &k8s.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"
}
matchesLabelSelector := func(opts *metav1.ListOptions) {
opts.LabelSelector = c.ingressLabelSelector
}
serverVersion, err := c.GetServerVersion()
if err != nil {
return nil, fmt.Errorf("failed to get server version: %w", err)
}
for _, ns := range namespaces {
factoryIngress := informers.NewSharedInformerFactoryWithOptions(c.clientset, resyncPeriod, informers.WithNamespace(ns), informers.WithTweakListOptions(matchesLabelSelector))
if supportsNetworkingV1Ingress(serverVersion) {
factoryIngress.Networking().V1().Ingresses().Informer().AddEventHandler(eventHandler)
} else {
factoryIngress.Networking().V1beta1().Ingresses().Informer().AddEventHandler(eventHandler)
}
c.factoriesIngress[ns] = factoryIngress
factoryKube := informers.NewSharedInformerFactoryWithOptions(c.clientset, resyncPeriod, informers.WithNamespace(ns))
factoryKube.Core().V1().Services().Informer().AddEventHandler(eventHandler)
factoryKube.Core().V1().Endpoints().Informer().AddEventHandler(eventHandler)
c.factoriesKube[ns] = factoryKube
factorySecret := informers.NewSharedInformerFactoryWithOptions(c.clientset, resyncPeriod, informers.WithNamespace(ns), informers.WithTweakListOptions(notOwnedByHelm))
factorySecret.Core().V1().Secrets().Informer().AddEventHandler(eventHandler)
c.factoriesSecret[ns] = factorySecret
}
for _, ns := range namespaces {
c.factoriesIngress[ns].Start(stopCh)
c.factoriesKube[ns].Start(stopCh)
c.factoriesSecret[ns].Start(stopCh)
}
for _, ns := range namespaces {
for typ, ok := range c.factoriesIngress[ns].WaitForCacheSync(stopCh) {
if !ok {
return nil, fmt.Errorf("timed out waiting for controller caches to sync %s in namespace %q", typ, ns)
}
}
for typ, 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", typ, ns)
}
}
for typ, 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", typ, ns)
}
}
}
if supportsIngressClass(serverVersion) {
c.clusterFactory = informers.NewSharedInformerFactoryWithOptions(c.clientset, resyncPeriod)
c.clusterFactory.Networking().V1beta1().IngressClasses().Informer().AddEventHandler(eventHandler)
c.clusterFactory.Start(stopCh)
for typ, ok := range c.clusterFactory.WaitForCacheSync(stopCh) {
if !ok {
return nil, fmt.Errorf("timed out waiting for controller caches to sync %s", typ)
}
}
}
return eventCh, nil
}
// GetIngresses returns all Ingresses for observed namespaces in the cluster.
func (c *clientWrapper) GetIngresses() []*networkingv1.Ingress {
var results []*networkingv1.Ingress
serverVersion, err := c.GetServerVersion()
if err != nil {
log.Errorf("Failed to get server version: %v", err)
return results
}
isNetworkingV1Supported := supportsNetworkingV1Ingress(serverVersion)
for ns, factory := range c.factoriesIngress {
if isNetworkingV1Supported {
// networking
listNew, err := factory.Networking().V1().Ingresses().Lister().List(labels.Everything())
if err != nil {
log.WithoutContext().Errorf("Failed to list ingresses in namespace %s: %v", ns, err)
continue
}
results = append(results, listNew...)
continue
}
// networking beta
list, err := factory.Networking().V1beta1().Ingresses().Lister().List(labels.Everything())
if err != nil {
log.WithoutContext().Errorf("Failed to list ingresses in namespace %s: %v", ns, err)
continue
}
for _, ing := range list {
n, err := toNetworkingV1(ing)
if err != nil {
log.WithoutContext().Errorf("Failed to convert ingress %s from networking/v1beta1 to networking/v1: %v", ns, err)
continue
}
addServiceFromV1Beta1(n, *ing)
results = append(results, n)
}
}
return results
}
func toNetworkingV1(ing marshaler) (*networkingv1.Ingress, error) {
data, err := ing.Marshal()
if err != nil {
return nil, err
}
ni := &networkingv1.Ingress{}
err = ni.Unmarshal(data)
if err != nil {
return nil, err
}
return ni, nil
}
func addServiceFromV1Beta1(ing *networkingv1.Ingress, old networkingv1beta1.Ingress) {
if old.Spec.Backend != nil {
port := networkingv1.ServiceBackendPort{}
if old.Spec.Backend.ServicePort.Type == intstr.Int {
port.Number = old.Spec.Backend.ServicePort.IntVal
} else {
port.Name = old.Spec.Backend.ServicePort.StrVal
}
if old.Spec.Backend.ServiceName != "" {
ing.Spec.DefaultBackend = &networkingv1.IngressBackend{
Service: &networkingv1.IngressServiceBackend{
Name: old.Spec.Backend.ServiceName,
Port: port,
},
}
}
}
for rc, rule := range ing.Spec.Rules {
if rule.HTTP == nil {
continue
}
for pc, path := range rule.HTTP.Paths {
if path.Backend.Service == nil {
oldBackend := old.Spec.Rules[rc].HTTP.Paths[pc].Backend
port := networkingv1.ServiceBackendPort{}
if oldBackend.ServicePort.Type == intstr.Int {
port.Number = oldBackend.ServicePort.IntVal
} else {
port.Name = oldBackend.ServicePort.StrVal
}
svc := networkingv1.IngressServiceBackend{
Name: oldBackend.ServiceName,
Port: port,
}
ing.Spec.Rules[rc].HTTP.Paths[pc].Backend.Service = &svc
}
}
}
}
// UpdateIngressStatus updates an Ingress with a provided status.
func (c *clientWrapper) UpdateIngressStatus(src *networkingv1.Ingress, ingStatus []corev1.LoadBalancerIngress) error {
if !c.isWatchedNamespace(src.Namespace) {
return fmt.Errorf("failed to get ingress %s/%s: namespace is not within watched namespaces", src.Namespace, src.Name)
}
serverVersion, err := c.GetServerVersion()
if err != nil {
log.WithoutContext().Errorf("Failed to get server version: %v", err)
return err
}
if !supportsNetworkingV1Ingress(serverVersion) {
return c.updateIngressStatusOld(src, ingStatus)
}
ing, err := c.factoriesIngress[c.lookupNamespace(src.Namespace)].Networking().V1().Ingresses().Lister().Ingresses(src.Namespace).Get(src.Name)
if err != nil {
return fmt.Errorf("failed to get ingress %s/%s: %w", src.Namespace, src.Name, err)
}
logger := log.WithoutContext().WithField("namespace", ing.Namespace).WithField("ingress", ing.Name)
if isLoadBalancerIngressEquals(ing.Status.LoadBalancer.Ingress, ingStatus) {
logger.Debug("Skipping ingress status update")
return nil
}
ingCopy := ing.DeepCopy()
ingCopy.Status = networkingv1.IngressStatus{LoadBalancer: corev1.LoadBalancerStatus{Ingress: ingStatus}}
ctx, cancel := context.WithTimeout(context.Background(), defaultTimeout)
defer cancel()
_, err = c.clientset.NetworkingV1().Ingresses(ingCopy.Namespace).UpdateStatus(ctx, ingCopy, metav1.UpdateOptions{})
if err != nil {
return fmt.Errorf("failed to update ingress status %s/%s: %w", src.Namespace, src.Name, err)
}
logger.Info("Updated ingress status")
return nil
}
func (c *clientWrapper) updateIngressStatusOld(src *networkingv1.Ingress, ingStatus []corev1.LoadBalancerIngress) error {
ing, err := c.factoriesIngress[c.lookupNamespace(src.Namespace)].Networking().V1beta1().Ingresses().Lister().Ingresses(src.Namespace).Get(src.Name)
if err != nil {
return fmt.Errorf("failed to get ingress %s/%s: %w", src.Namespace, src.Name, err)
}
logger := log.WithoutContext().WithField("namespace", ing.Namespace).WithField("ingress", ing.Name)
if isLoadBalancerIngressEquals(ing.Status.LoadBalancer.Ingress, ingStatus) {
logger.Debug("Skipping ingress status update")
return nil
}
ingCopy := ing.DeepCopy()
ingCopy.Status = networkingv1beta1.IngressStatus{LoadBalancer: corev1.LoadBalancerStatus{Ingress: ingStatus}}
ctx, cancel := context.WithTimeout(context.Background(), defaultTimeout)
defer cancel()
_, err = c.clientset.NetworkingV1beta1().Ingresses(ingCopy.Namespace).UpdateStatus(ctx, ingCopy, metav1.UpdateOptions{})
if err != nil {
return fmt.Errorf("failed to update ingress status %s/%s: %w", src.Namespace, src.Name, err)
}
logger.Info("Updated ingress status")
return nil
}
// isLoadBalancerIngressEquals returns true if the given slices are equal, false otherwise.
func isLoadBalancerIngressEquals(aSlice, bSlice []corev1.LoadBalancerIngress) bool {
if len(aSlice) != len(bSlice) {
return false
}
aMap := make(map[string]struct{})
for _, aIngress := range aSlice {
aMap[aIngress.Hostname+aIngress.IP] = struct{}{}
}
for _, bIngress := range bSlice {
if _, exists := aMap[bIngress.Hostname+bIngress.IP]; !exists {
return false
}
}
return true
}
// 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
}
func (c *clientWrapper) GetIngressClasses() ([]*networkingv1beta1.IngressClass, error) {
if c.clusterFactory == nil {
return nil, errors.New("cluster factory not loaded")
}
ingressClasses, err := c.clusterFactory.Networking().V1beta1().IngressClasses().Lister().List(labels.Everything())
if err != nil {
return nil, err
}
var ics []*networkingv1beta1.IngressClass
for _, ic := range ingressClasses {
if ic.Spec.Controller == traefikDefaultIngressClassController {
ics = append(ics, ic)
}
}
return ics, nil
}
// 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
}
// GetServerVersion returns the cluster server version, or an error.
func (c *clientWrapper) GetServerVersion() (*version.Version, error) {
serverVersion, err := c.clientset.Discovery().ServerVersion()
if err != nil {
return nil, fmt.Errorf("could not retrieve server version: %w", err)
}
return version.NewVersion(serverVersion.GitVersion)
}
// 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
}
// IngressClass objects are supported since Kubernetes v1.18.
// See https://kubernetes.io/docs/concepts/services-networking/ingress/#ingress-class
func supportsIngressClass(serverVersion *version.Version) bool {
ingressClassVersion := version.Must(version.NewVersion("1.18"))
return ingressClassVersion.LessThanOrEqual(serverVersion)
}
// filterIngressClassByName return a slice containing ingressclasses with the correct name.
func filterIngressClassByName(ingressClassName string, ics []*networkingv1beta1.IngressClass) []*networkingv1beta1.IngressClass {
var ingressClasses []*networkingv1beta1.IngressClass
for _, ic := range ics {
if ic.Name == ingressClassName {
ingressClasses = append(ingressClasses, ic)
}
}
return ingressClasses
}
// Ingress in networking.k8s.io/v1 is supported starting 1.19.
// thus, we query it in K8s starting 1.19.
func supportsNetworkingV1Ingress(serverVersion *version.Version) bool {
ingressNetworkingVersion := version.Must(version.NewVersion("1.19"))
return serverVersion.GreaterThanOrEqual(ingressNetworkingVersion)
}