prometheus/discovery/kubernetes/endpointslice.go

508 lines
15 KiB
Go

// Copyright 2020 The Prometheus 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 kubernetes
import (
"context"
"errors"
"fmt"
"log/slog"
"net"
"strconv"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/common/model"
"github.com/prometheus/common/promslog"
apiv1 "k8s.io/api/core/v1"
v1 "k8s.io/api/discovery/v1"
"k8s.io/client-go/tools/cache"
"k8s.io/client-go/util/workqueue"
"github.com/prometheus/prometheus/discovery/targetgroup"
"github.com/prometheus/prometheus/util/strutil"
)
// EndpointSlice discovers new endpoint targets.
type EndpointSlice struct {
logger *slog.Logger
endpointSliceInf cache.SharedIndexInformer
serviceInf cache.SharedInformer
podInf cache.SharedInformer
nodeInf cache.SharedInformer
withNodeMetadata bool
podStore cache.Store
endpointSliceStore cache.Store
serviceStore cache.Store
queue *workqueue.Type
}
// NewEndpointSlice returns a new endpointslice discovery.
func NewEndpointSlice(l *slog.Logger, eps cache.SharedIndexInformer, svc, pod, node cache.SharedInformer, eventCount *prometheus.CounterVec) *EndpointSlice {
if l == nil {
l = promslog.NewNopLogger()
}
epslAddCount := eventCount.WithLabelValues(RoleEndpointSlice.String(), MetricLabelRoleAdd)
epslUpdateCount := eventCount.WithLabelValues(RoleEndpointSlice.String(), MetricLabelRoleUpdate)
epslDeleteCount := eventCount.WithLabelValues(RoleEndpointSlice.String(), MetricLabelRoleDelete)
svcAddCount := eventCount.WithLabelValues(RoleService.String(), MetricLabelRoleAdd)
svcUpdateCount := eventCount.WithLabelValues(RoleService.String(), MetricLabelRoleUpdate)
svcDeleteCount := eventCount.WithLabelValues(RoleService.String(), MetricLabelRoleDelete)
e := &EndpointSlice{
logger: l,
endpointSliceInf: eps,
endpointSliceStore: eps.GetStore(),
serviceInf: svc,
serviceStore: svc.GetStore(),
podInf: pod,
podStore: pod.GetStore(),
nodeInf: node,
withNodeMetadata: node != nil,
queue: workqueue.NewNamed(RoleEndpointSlice.String()),
}
_, err := e.endpointSliceInf.AddEventHandler(cache.ResourceEventHandlerFuncs{
AddFunc: func(o interface{}) {
epslAddCount.Inc()
e.enqueue(o)
},
UpdateFunc: func(_, o interface{}) {
epslUpdateCount.Inc()
e.enqueue(o)
},
DeleteFunc: func(o interface{}) {
epslDeleteCount.Inc()
e.enqueue(o)
},
})
if err != nil {
l.Error("Error adding endpoint slices event handler.", "err", err)
}
serviceUpdate := func(o interface{}) {
svc, err := convertToService(o)
if err != nil {
e.logger.Error("converting to Service object failed", "err", err)
return
}
// TODO(brancz): use cache.Indexer to index endpointslices by
// LabelServiceName so this operation doesn't have to iterate over all
// endpoint objects.
for _, obj := range e.endpointSliceStore.List() {
esa, err := e.getEndpointSliceAdaptor(obj)
if err != nil {
e.logger.Error("converting to EndpointSlice object failed", "err", err)
continue
}
if lv, exists := esa.labels()[esa.labelServiceName()]; exists && lv == svc.Name {
e.enqueue(esa.get())
}
}
}
_, err = e.serviceInf.AddEventHandler(cache.ResourceEventHandlerFuncs{
AddFunc: func(o interface{}) {
svcAddCount.Inc()
serviceUpdate(o)
},
UpdateFunc: func(_, o interface{}) {
svcUpdateCount.Inc()
serviceUpdate(o)
},
DeleteFunc: func(o interface{}) {
svcDeleteCount.Inc()
serviceUpdate(o)
},
})
if err != nil {
l.Error("Error adding services event handler.", "err", err)
}
if e.withNodeMetadata {
_, err = e.nodeInf.AddEventHandler(cache.ResourceEventHandlerFuncs{
AddFunc: func(o interface{}) {
node := o.(*apiv1.Node)
e.enqueueNode(node.Name)
},
UpdateFunc: func(_, o interface{}) {
node := o.(*apiv1.Node)
e.enqueueNode(node.Name)
},
DeleteFunc: func(o interface{}) {
node := o.(*apiv1.Node)
e.enqueueNode(node.Name)
},
})
if err != nil {
l.Error("Error adding nodes event handler.", "err", err)
}
}
return e
}
func (e *EndpointSlice) enqueueNode(nodeName string) {
endpoints, err := e.endpointSliceInf.GetIndexer().ByIndex(nodeIndex, nodeName)
if err != nil {
e.logger.Error("Error getting endpoints for node", "node", nodeName, "err", err)
return
}
for _, endpoint := range endpoints {
e.enqueue(endpoint)
}
}
func (e *EndpointSlice) enqueue(obj interface{}) {
key, err := cache.DeletionHandlingMetaNamespaceKeyFunc(obj)
if err != nil {
return
}
e.queue.Add(key)
}
// Run implements the Discoverer interface.
func (e *EndpointSlice) Run(ctx context.Context, ch chan<- []*targetgroup.Group) {
defer e.queue.ShutDown()
cacheSyncs := []cache.InformerSynced{e.endpointSliceInf.HasSynced, e.serviceInf.HasSynced, e.podInf.HasSynced}
if e.withNodeMetadata {
cacheSyncs = append(cacheSyncs, e.nodeInf.HasSynced)
}
if !cache.WaitForCacheSync(ctx.Done(), cacheSyncs...) {
if !errors.Is(ctx.Err(), context.Canceled) {
e.logger.Error("endpointslice informer unable to sync cache")
}
return
}
go func() {
for e.process(ctx, ch) {
}
}()
// Block until the target provider is explicitly canceled.
<-ctx.Done()
}
func (e *EndpointSlice) process(ctx context.Context, ch chan<- []*targetgroup.Group) bool {
keyObj, quit := e.queue.Get()
if quit {
return false
}
defer e.queue.Done(keyObj)
key := keyObj.(string)
namespace, name, err := cache.SplitMetaNamespaceKey(key)
if err != nil {
e.logger.Error("splitting key failed", "key", key)
return true
}
o, exists, err := e.endpointSliceStore.GetByKey(key)
if err != nil {
e.logger.Error("getting object from store failed", "key", key)
return true
}
if !exists {
send(ctx, ch, &targetgroup.Group{Source: endpointSliceSourceFromNamespaceAndName(namespace, name)})
return true
}
esa, err := e.getEndpointSliceAdaptor(o)
if err != nil {
e.logger.Error("converting to EndpointSlice object failed", "err", err)
return true
}
send(ctx, ch, e.buildEndpointSlice(esa))
return true
}
func (e *EndpointSlice) getEndpointSliceAdaptor(o interface{}) (endpointSliceAdaptor, error) {
switch endpointSlice := o.(type) {
case *v1.EndpointSlice:
return newEndpointSliceAdaptorFromV1(endpointSlice), nil
default:
return nil, fmt.Errorf("received unexpected object: %v", o)
}
}
func endpointSliceSource(ep endpointSliceAdaptor) string {
return endpointSliceSourceFromNamespaceAndName(ep.namespace(), ep.name())
}
func endpointSliceSourceFromNamespaceAndName(namespace, name string) string {
return "endpointslice/" + namespace + "/" + name
}
const (
endpointSliceAddressTypeLabel = metaLabelPrefix + "endpointslice_address_type"
endpointSlicePortNameLabel = metaLabelPrefix + "endpointslice_port_name"
endpointSlicePortProtocolLabel = metaLabelPrefix + "endpointslice_port_protocol"
endpointSlicePortLabel = metaLabelPrefix + "endpointslice_port"
endpointSlicePortAppProtocol = metaLabelPrefix + "endpointslice_port_app_protocol"
endpointSliceEndpointConditionsReadyLabel = metaLabelPrefix + "endpointslice_endpoint_conditions_ready"
endpointSliceEndpointConditionsServingLabel = metaLabelPrefix + "endpointslice_endpoint_conditions_serving"
endpointSliceEndpointConditionsTerminatingLabel = metaLabelPrefix + "endpointslice_endpoint_conditions_terminating"
endpointSliceEndpointZoneLabel = metaLabelPrefix + "endpointslice_endpoint_zone"
endpointSliceEndpointHostnameLabel = metaLabelPrefix + "endpointslice_endpoint_hostname"
endpointSliceEndpointNodenameLabel = metaLabelPrefix + "endpointslice_endpoint_node_name"
endpointSliceAddressTargetKindLabel = metaLabelPrefix + "endpointslice_address_target_kind"
endpointSliceAddressTargetNameLabel = metaLabelPrefix + "endpointslice_address_target_name"
endpointSliceEndpointTopologyLabelPrefix = metaLabelPrefix + "endpointslice_endpoint_topology_"
endpointSliceEndpointTopologyLabelPresentPrefix = metaLabelPrefix + "endpointslice_endpoint_topology_present_"
)
func (e *EndpointSlice) buildEndpointSlice(eps endpointSliceAdaptor) *targetgroup.Group {
tg := &targetgroup.Group{
Source: endpointSliceSource(eps),
}
tg.Labels = model.LabelSet{
namespaceLabel: lv(eps.namespace()),
endpointSliceAddressTypeLabel: lv(eps.addressType()),
}
addObjectMetaLabels(tg.Labels, eps.getObjectMeta(), RoleEndpointSlice)
e.addServiceLabels(eps, tg)
type podEntry struct {
pod *apiv1.Pod
servicePorts []endpointSlicePortAdaptor
}
seenPods := map[string]*podEntry{}
add := func(addr string, ep endpointSliceEndpointAdaptor, port endpointSlicePortAdaptor) {
a := addr
if port.port() != nil {
a = net.JoinHostPort(addr, strconv.FormatUint(uint64(*port.port()), 10))
}
target := model.LabelSet{
model.AddressLabel: lv(a),
}
if port.name() != nil {
target[endpointSlicePortNameLabel] = lv(*port.name())
}
if port.protocol() != nil {
target[endpointSlicePortProtocolLabel] = lv(*port.protocol())
}
if port.port() != nil {
target[endpointSlicePortLabel] = lv(strconv.FormatUint(uint64(*port.port()), 10))
}
if port.appProtocol() != nil {
target[endpointSlicePortAppProtocol] = lv(*port.appProtocol())
}
if ep.conditions().ready() != nil {
target[endpointSliceEndpointConditionsReadyLabel] = lv(strconv.FormatBool(*ep.conditions().ready()))
}
if ep.conditions().serving() != nil {
target[endpointSliceEndpointConditionsServingLabel] = lv(strconv.FormatBool(*ep.conditions().serving()))
}
if ep.conditions().terminating() != nil {
target[endpointSliceEndpointConditionsTerminatingLabel] = lv(strconv.FormatBool(*ep.conditions().terminating()))
}
if ep.hostname() != nil {
target[endpointSliceEndpointHostnameLabel] = lv(*ep.hostname())
}
if ep.targetRef() != nil {
target[model.LabelName(endpointSliceAddressTargetKindLabel)] = lv(ep.targetRef().Kind)
target[model.LabelName(endpointSliceAddressTargetNameLabel)] = lv(ep.targetRef().Name)
}
if ep.nodename() != nil {
target[endpointSliceEndpointNodenameLabel] = lv(*ep.nodename())
}
if ep.zone() != nil {
target[model.LabelName(endpointSliceEndpointZoneLabel)] = lv(*ep.zone())
}
for k, v := range ep.topology() {
ln := strutil.SanitizeLabelName(k)
target[model.LabelName(endpointSliceEndpointTopologyLabelPrefix+ln)] = lv(v)
target[model.LabelName(endpointSliceEndpointTopologyLabelPresentPrefix+ln)] = presentValue
}
if e.withNodeMetadata {
if ep.targetRef() != nil && ep.targetRef().Kind == "Node" {
target = addNodeLabels(target, e.nodeInf, e.logger, &ep.targetRef().Name)
} else {
target = addNodeLabels(target, e.nodeInf, e.logger, ep.nodename())
}
}
pod := e.resolvePodRef(ep.targetRef())
if pod == nil {
// This target is not a Pod, so don't continue with Pod specific logic.
tg.Targets = append(tg.Targets, target)
return
}
s := namespacedName(pod.Namespace, pod.Name)
sp, ok := seenPods[s]
if !ok {
sp = &podEntry{pod: pod}
seenPods[s] = sp
}
// Attach standard pod labels.
target = target.Merge(podLabels(pod))
// Attach potential container port labels matching the endpoint port.
containers := append(pod.Spec.Containers, pod.Spec.InitContainers...)
for i, c := range containers {
for _, cport := range c.Ports {
if port.port() == nil {
continue
}
if *port.port() == cport.ContainerPort {
ports := strconv.FormatUint(uint64(*port.port()), 10)
isInit := i >= len(pod.Spec.Containers)
target[podContainerNameLabel] = lv(c.Name)
target[podContainerImageLabel] = lv(c.Image)
target[podContainerPortNameLabel] = lv(cport.Name)
target[podContainerPortNumberLabel] = lv(ports)
target[podContainerPortProtocolLabel] = lv(string(cport.Protocol))
target[podContainerIsInit] = lv(strconv.FormatBool(isInit))
break
}
}
}
// Add service port so we know that we have already generated a target
// for it.
sp.servicePorts = append(sp.servicePorts, port)
tg.Targets = append(tg.Targets, target)
}
for _, ep := range eps.endpoints() {
for _, port := range eps.ports() {
for _, addr := range ep.addresses() {
add(addr, ep, port)
}
}
}
// For all seen pods, check all container ports. If they were not covered
// by one of the service endpoints, generate targets for them.
for _, pe := range seenPods {
// PodIP can be empty when a pod is starting or has been evicted.
if len(pe.pod.Status.PodIP) == 0 {
continue
}
containers := append(pe.pod.Spec.Containers, pe.pod.Spec.InitContainers...)
for i, c := range containers {
for _, cport := range c.Ports {
hasSeenPort := func() bool {
for _, eport := range pe.servicePorts {
if eport.port() == nil {
continue
}
if cport.ContainerPort == *eport.port() {
return true
}
}
return false
}
if hasSeenPort() {
continue
}
a := net.JoinHostPort(pe.pod.Status.PodIP, strconv.FormatUint(uint64(cport.ContainerPort), 10))
ports := strconv.FormatUint(uint64(cport.ContainerPort), 10)
isInit := i >= len(pe.pod.Spec.Containers)
target := model.LabelSet{
model.AddressLabel: lv(a),
podContainerNameLabel: lv(c.Name),
podContainerImageLabel: lv(c.Image),
podContainerPortNameLabel: lv(cport.Name),
podContainerPortNumberLabel: lv(ports),
podContainerPortProtocolLabel: lv(string(cport.Protocol)),
podContainerIsInit: lv(strconv.FormatBool(isInit)),
}
tg.Targets = append(tg.Targets, target.Merge(podLabels(pe.pod)))
}
}
}
return tg
}
func (e *EndpointSlice) resolvePodRef(ref *apiv1.ObjectReference) *apiv1.Pod {
if ref == nil || ref.Kind != "Pod" {
return nil
}
p := &apiv1.Pod{}
p.Namespace = ref.Namespace
p.Name = ref.Name
obj, exists, err := e.podStore.Get(p)
if err != nil {
e.logger.Error("resolving pod ref failed", "err", err)
return nil
}
if !exists {
return nil
}
return obj.(*apiv1.Pod)
}
func (e *EndpointSlice) addServiceLabels(esa endpointSliceAdaptor, tg *targetgroup.Group) {
var (
svc = &apiv1.Service{}
found bool
)
svc.Namespace = esa.namespace()
// Every EndpointSlice object has the Service they belong to in the
// kubernetes.io/service-name label.
svc.Name, found = esa.labels()[esa.labelServiceName()]
if !found {
return
}
obj, exists, err := e.serviceStore.Get(svc)
if err != nil {
e.logger.Error("retrieving service failed", "err", err)
return
}
if !exists {
return
}
svc = obj.(*apiv1.Service)
tg.Labels = tg.Labels.Merge(serviceLabels(svc))
}