mirror of
https://github.com/kubernetes-sigs/external-dns.git
synced 2025-10-31 10:41:16 +01:00
297 lines
8.9 KiB
Go
297 lines
8.9 KiB
Go
/*
|
|
Copyright 2018 The Kubernetes 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 source
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
"os"
|
|
"strings"
|
|
|
|
"k8s.io/apimachinery/pkg/util/wait"
|
|
"k8s.io/apimachinery/pkg/watch"
|
|
"k8s.io/client-go/tools/cache"
|
|
|
|
log "github.com/sirupsen/logrus"
|
|
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
|
|
"k8s.io/apimachinery/pkg/labels"
|
|
"k8s.io/apimachinery/pkg/runtime"
|
|
"k8s.io/apimachinery/pkg/runtime/schema"
|
|
"k8s.io/apimachinery/pkg/runtime/serializer"
|
|
"k8s.io/client-go/kubernetes"
|
|
"k8s.io/client-go/rest"
|
|
"k8s.io/client-go/tools/clientcmd"
|
|
|
|
"sigs.k8s.io/external-dns/endpoint"
|
|
)
|
|
|
|
// crdSource is an implementation of Source that provides endpoints by listing
|
|
// specified CRD and fetching Endpoints embedded in Spec.
|
|
type crdSource struct {
|
|
crdClient rest.Interface
|
|
namespace string
|
|
crdResource string
|
|
codec runtime.ParameterCodec
|
|
annotationFilter string
|
|
labelSelector labels.Selector
|
|
informer *cache.SharedInformer
|
|
}
|
|
|
|
func addKnownTypes(scheme *runtime.Scheme, groupVersion schema.GroupVersion) error {
|
|
scheme.AddKnownTypes(groupVersion,
|
|
&endpoint.DNSEndpoint{},
|
|
&endpoint.DNSEndpointList{},
|
|
)
|
|
metav1.AddToGroupVersion(scheme, groupVersion)
|
|
return nil
|
|
}
|
|
|
|
// NewCRDClientForAPIVersionKind return rest client for the given apiVersion and kind of the CRD
|
|
func NewCRDClientForAPIVersionKind(client kubernetes.Interface, kubeConfig, apiServerURL, apiVersion, kind string) (*rest.RESTClient, *runtime.Scheme, error) {
|
|
if kubeConfig == "" {
|
|
if _, err := os.Stat(clientcmd.RecommendedHomeFile); err == nil {
|
|
kubeConfig = clientcmd.RecommendedHomeFile
|
|
}
|
|
}
|
|
|
|
config, err := clientcmd.BuildConfigFromFlags(apiServerURL, kubeConfig)
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
|
|
groupVersion, err := schema.ParseGroupVersion(apiVersion)
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
apiResourceList, err := client.Discovery().ServerResourcesForGroupVersion(groupVersion.String())
|
|
if err != nil {
|
|
return nil, nil, fmt.Errorf("error listing resources in GroupVersion %q: %w", groupVersion.String(), err)
|
|
}
|
|
|
|
var crdAPIResource *metav1.APIResource
|
|
for _, apiResource := range apiResourceList.APIResources {
|
|
if apiResource.Kind == kind {
|
|
crdAPIResource = &apiResource
|
|
break
|
|
}
|
|
}
|
|
if crdAPIResource == nil {
|
|
return nil, nil, fmt.Errorf("unable to find Resource Kind %q in GroupVersion %q", kind, apiVersion)
|
|
}
|
|
|
|
scheme := runtime.NewScheme()
|
|
addKnownTypes(scheme, groupVersion)
|
|
|
|
config.ContentConfig.GroupVersion = &groupVersion
|
|
config.APIPath = "/apis"
|
|
config.NegotiatedSerializer = serializer.WithoutConversionCodecFactory{CodecFactory: serializer.NewCodecFactory(scheme)}
|
|
|
|
crdClient, err := rest.UnversionedRESTClientFor(config)
|
|
if err != nil {
|
|
return nil, nil, err
|
|
}
|
|
return crdClient, scheme, nil
|
|
}
|
|
|
|
// NewCRDSource creates a new crdSource with the given config.
|
|
func NewCRDSource(crdClient rest.Interface, namespace, kind string, annotationFilter string, labelSelector labels.Selector, scheme *runtime.Scheme, startInformer bool) (Source, error) {
|
|
sourceCrd := crdSource{
|
|
crdResource: strings.ToLower(kind) + "s",
|
|
namespace: namespace,
|
|
annotationFilter: annotationFilter,
|
|
labelSelector: labelSelector,
|
|
crdClient: crdClient,
|
|
codec: runtime.NewParameterCodec(scheme),
|
|
}
|
|
if startInformer {
|
|
// external-dns already runs its sync-handler periodically (controlled by `--interval` flag) to ensure any
|
|
// missed or dropped events are handled. specify a resync period 0 to avoid unnecessary sync handler invocations.
|
|
informer := cache.NewSharedInformer(
|
|
&cache.ListWatch{
|
|
ListFunc: func(lo metav1.ListOptions) (result runtime.Object, err error) {
|
|
return sourceCrd.List(context.TODO(), &lo)
|
|
},
|
|
WatchFunc: func(lo metav1.ListOptions) (watch.Interface, error) {
|
|
return sourceCrd.watch(context.TODO(), &lo)
|
|
},
|
|
},
|
|
&endpoint.DNSEndpoint{},
|
|
0)
|
|
sourceCrd.informer = &informer
|
|
go informer.Run(wait.NeverStop)
|
|
}
|
|
return &sourceCrd, nil
|
|
}
|
|
|
|
func (cs *crdSource) AddEventHandler(ctx context.Context, handler func()) {
|
|
if cs.informer != nil {
|
|
log.Debug("Adding event handler for CRD")
|
|
// Right now there is no way to remove event handler from informer, see:
|
|
// https://github.com/kubernetes/kubernetes/issues/79610
|
|
informer := *cs.informer
|
|
informer.AddEventHandler(
|
|
cache.ResourceEventHandlerFuncs{
|
|
AddFunc: func(obj interface{}) {
|
|
handler()
|
|
},
|
|
UpdateFunc: func(old interface{}, new interface{}) {
|
|
handler()
|
|
},
|
|
DeleteFunc: func(obj interface{}) {
|
|
handler()
|
|
},
|
|
},
|
|
)
|
|
}
|
|
}
|
|
|
|
// Endpoints returns endpoint objects.
|
|
func (cs *crdSource) Endpoints(ctx context.Context) ([]*endpoint.Endpoint, error) {
|
|
endpoints := []*endpoint.Endpoint{}
|
|
|
|
var (
|
|
result *endpoint.DNSEndpointList
|
|
err error
|
|
)
|
|
|
|
result, err = cs.List(ctx, &metav1.ListOptions{LabelSelector: cs.labelSelector.String()})
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
result, err = cs.filterByAnnotations(result)
|
|
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
for _, dnsEndpoint := range result.Items {
|
|
// Make sure that all endpoints have targets for A or CNAME type
|
|
crdEndpoints := []*endpoint.Endpoint{}
|
|
for _, ep := range dnsEndpoint.Spec.Endpoints {
|
|
if (ep.RecordType == "CNAME" || ep.RecordType == "A" || ep.RecordType == "AAAA") && len(ep.Targets) < 1 {
|
|
log.Warnf("Endpoint %s with DNSName %s has an empty list of targets", dnsEndpoint.ObjectMeta.Name, ep.DNSName)
|
|
continue
|
|
}
|
|
|
|
illegalTarget := false
|
|
for _, target := range ep.Targets {
|
|
if strings.HasSuffix(target, ".") {
|
|
illegalTarget = true
|
|
break
|
|
}
|
|
}
|
|
if illegalTarget {
|
|
log.Warnf("Endpoint %s with DNSName %s has an illegal target. The subdomain must consist of lower case alphanumeric characters, '-' or '.', and must start and end with an alphanumeric character (e.g. 'example.com')", dnsEndpoint.ObjectMeta.Name, ep.DNSName)
|
|
continue
|
|
}
|
|
|
|
if ep.Labels == nil {
|
|
ep.Labels = endpoint.NewLabels()
|
|
}
|
|
|
|
crdEndpoints = append(crdEndpoints, ep)
|
|
}
|
|
|
|
cs.setResourceLabel(&dnsEndpoint, crdEndpoints)
|
|
endpoints = append(endpoints, crdEndpoints...)
|
|
|
|
if dnsEndpoint.Status.ObservedGeneration == dnsEndpoint.Generation {
|
|
continue
|
|
}
|
|
|
|
dnsEndpoint.Status.ObservedGeneration = dnsEndpoint.Generation
|
|
// Update the ObservedGeneration
|
|
_, err = cs.UpdateStatus(ctx, &dnsEndpoint)
|
|
if err != nil {
|
|
log.Warnf("Could not update ObservedGeneration of the CRD: %v", err)
|
|
}
|
|
}
|
|
|
|
return endpoints, nil
|
|
}
|
|
|
|
func (cs *crdSource) setResourceLabel(crd *endpoint.DNSEndpoint, endpoints []*endpoint.Endpoint) {
|
|
for _, ep := range endpoints {
|
|
ep.Labels[endpoint.ResourceLabelKey] = fmt.Sprintf("crd/%s/%s", crd.ObjectMeta.Namespace, crd.ObjectMeta.Name)
|
|
}
|
|
}
|
|
|
|
func (cs *crdSource) watch(ctx context.Context, opts *metav1.ListOptions) (watch.Interface, error) {
|
|
opts.Watch = true
|
|
return cs.crdClient.Get().
|
|
Namespace(cs.namespace).
|
|
Resource(cs.crdResource).
|
|
VersionedParams(opts, cs.codec).
|
|
Watch(ctx)
|
|
}
|
|
|
|
func (cs *crdSource) List(ctx context.Context, opts *metav1.ListOptions) (result *endpoint.DNSEndpointList, err error) {
|
|
result = &endpoint.DNSEndpointList{}
|
|
err = cs.crdClient.Get().
|
|
Namespace(cs.namespace).
|
|
Resource(cs.crdResource).
|
|
VersionedParams(opts, cs.codec).
|
|
Do(ctx).
|
|
Into(result)
|
|
return
|
|
}
|
|
|
|
func (cs *crdSource) UpdateStatus(ctx context.Context, dnsEndpoint *endpoint.DNSEndpoint) (result *endpoint.DNSEndpoint, err error) {
|
|
result = &endpoint.DNSEndpoint{}
|
|
err = cs.crdClient.Put().
|
|
Namespace(dnsEndpoint.Namespace).
|
|
Resource(cs.crdResource).
|
|
Name(dnsEndpoint.Name).
|
|
SubResource("status").
|
|
Body(dnsEndpoint).
|
|
Do(ctx).
|
|
Into(result)
|
|
return
|
|
}
|
|
|
|
// filterByAnnotations filters a list of dnsendpoints by a given annotation selector.
|
|
func (cs *crdSource) filterByAnnotations(dnsendpoints *endpoint.DNSEndpointList) (*endpoint.DNSEndpointList, error) {
|
|
labelSelector, err := metav1.ParseToLabelSelector(cs.annotationFilter)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
selector, err := metav1.LabelSelectorAsSelector(labelSelector)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
// empty filter returns original list
|
|
if selector.Empty() {
|
|
return dnsendpoints, nil
|
|
}
|
|
|
|
filteredList := endpoint.DNSEndpointList{}
|
|
|
|
for _, dnsendpoint := range dnsendpoints.Items {
|
|
// convert the dnsendpoint' annotations to an equivalent label selector
|
|
annotations := labels.Set(dnsendpoint.Annotations)
|
|
|
|
// include dnsendpoint if its annotations match the selector
|
|
if selector.Matches(annotations) {
|
|
filteredList.Items = append(filteredList.Items, dnsendpoint)
|
|
}
|
|
}
|
|
|
|
return &filteredList, nil
|
|
}
|