prometheus/discovery/kubernetes/endpointslice.go

408 lines
12 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"
"net"
"strconv"
"github.com/go-kit/kit/log"
"github.com/go-kit/kit/log/level"
"github.com/pkg/errors"
"github.com/prometheus/common/model"
apiv1 "k8s.io/api/core/v1"
disv1beta1 "k8s.io/api/discovery/v1beta1"
"k8s.io/client-go/tools/cache"
"k8s.io/client-go/util/workqueue"
"github.com/prometheus/prometheus/discovery/targetgroup"
"github.com/prometheus/prometheus/util/strutil"
)
var (
epslAddCount = eventCount.WithLabelValues("endpointslice", "add")
epslUpdateCount = eventCount.WithLabelValues("endpointslice", "update")
epslDeleteCount = eventCount.WithLabelValues("endpointslice", "delete")
)
// EndpointSlice discovers new endpoint targets.
type EndpointSlice struct {
logger log.Logger
endpointSliceInf cache.SharedInformer
serviceInf cache.SharedInformer
podInf cache.SharedInformer
podStore cache.Store
endpointSliceStore cache.Store
serviceStore cache.Store
queue *workqueue.Type
}
// NewEndpointSlice returns a new endpointslice discovery.
func NewEndpointSlice(l log.Logger, svc, eps, pod cache.SharedInformer) *EndpointSlice {
if l == nil {
l = log.NewNopLogger()
}
e := &EndpointSlice{
logger: l,
endpointSliceInf: eps,
endpointSliceStore: eps.GetStore(),
serviceInf: svc,
serviceStore: svc.GetStore(),
podInf: pod,
podStore: pod.GetStore(),
queue: workqueue.NewNamed("endpointSlice"),
}
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)
},
})
serviceUpdate := func(o interface{}) {
svc, err := convertToService(o)
if err != nil {
level.Error(e.logger).Log("msg", "converting to Service object failed", "err", err)
return
}
// TODO(brancz): use cache.Indexer to index endpoints by
// disv1beta1.LabelServiceName so this operation doesn't have to
// iterate over all endpoint objects.
for _, obj := range e.endpointSliceStore.List() {
ep := obj.(*disv1beta1.EndpointSlice)
if lv, exists := ep.Labels[disv1beta1.LabelServiceName]; exists && lv == svc.Name {
e.enqueue(ep)
}
}
}
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)
},
})
return e
}
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()
if !cache.WaitForCacheSync(ctx.Done(), e.endpointSliceInf.HasSynced, e.serviceInf.HasSynced, e.podInf.HasSynced) {
if ctx.Err() != context.Canceled {
level.Error(e.logger).Log("msg", "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 {
level.Error(e.logger).Log("msg", "splitting key failed", "key", key)
return true
}
o, exists, err := e.endpointSliceStore.GetByKey(key)
if err != nil {
level.Error(e.logger).Log("msg", "getting object from store failed", "key", key)
return true
}
if !exists {
send(ctx, ch, &targetgroup.Group{Source: endpointSliceSourceFromNamespaceAndName(namespace, name)})
return true
}
eps, err := convertToEndpointSlice(o)
if err != nil {
level.Error(e.logger).Log("msg", "converting to EndpointSlice object failed", "err", err)
return true
}
send(ctx, ch, e.buildEndpointSlice(eps))
return true
}
func convertToEndpointSlice(o interface{}) (*disv1beta1.EndpointSlice, error) {
endpoints, ok := o.(*disv1beta1.EndpointSlice)
if ok {
return endpoints, nil
}
return nil, errors.Errorf("received unexpected object: %v", o)
}
func endpointSliceSource(ep *disv1beta1.EndpointSlice) string {
return endpointSliceSourceFromNamespaceAndName(ep.Namespace, ep.Name)
}
func endpointSliceSourceFromNamespaceAndName(namespace, name string) string {
return "endpointslice/" + namespace + "/" + name
}
const (
endpointSliceNameLabel = metaLabelPrefix + "endpointslice_name"
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"
endpointSliceEndpointHostnameLabel = metaLabelPrefix + "endpointslice_endpoint_hostname"
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 *disv1beta1.EndpointSlice) *targetgroup.Group {
tg := &targetgroup.Group{
Source: endpointSliceSource(eps),
}
tg.Labels = model.LabelSet{
namespaceLabel: lv(eps.Namespace),
endpointSliceNameLabel: lv(eps.Name),
endpointSliceAddressTypeLabel: lv(string(eps.AddressType)),
}
e.addServiceLabels(eps, tg)
type podEntry struct {
pod *apiv1.Pod
servicePorts []disv1beta1.EndpointPort
}
seenPods := map[string]*podEntry{}
add := func(addr string, ep disv1beta1.Endpoint, port disv1beta1.EndpointPort) {
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(string(*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.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)
}
for k, v := range ep.Topology {
ln := strutil.SanitizeLabelName(k)
target[model.LabelName(endpointSliceEndpointTopologyLabelPrefix+ln)] = lv(v)
target[model.LabelName(endpointSliceEndpointTopologyLabelPresentPrefix+ln)] = presentValue
}
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 := 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.
for _, c := range pod.Spec.Containers {
for _, cport := range c.Ports {
if port.Port == nil {
continue
}
if *port.Port == cport.ContainerPort {
ports := strconv.FormatUint(uint64(*port.Port), 10)
target[podContainerNameLabel] = lv(c.Name)
target[podContainerPortNameLabel] = lv(cport.Name)
target[podContainerPortNumberLabel] = lv(ports)
target[podContainerPortProtocolLabel] = lv(string(cport.Protocol))
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 {
for _, c := range pe.pod.Spec.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)
target := model.LabelSet{
model.AddressLabel: lv(a),
podContainerNameLabel: lv(c.Name),
podContainerPortNameLabel: lv(cport.Name),
podContainerPortNumberLabel: lv(ports),
podContainerPortProtocolLabel: lv(string(cport.Protocol)),
}
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 {
level.Error(e.logger).Log("msg", "resolving pod ref failed", "err", err)
return nil
}
if !exists {
return nil
}
return obj.(*apiv1.Pod)
}
func (e *EndpointSlice) addServiceLabels(eps *disv1beta1.EndpointSlice, tg *targetgroup.Group) {
var (
svc = &apiv1.Service{}
found bool
)
svc.Namespace = eps.Namespace
// Every EndpointSlice object has the Service they belong to in the
// kubernetes.io/service-name label.
svc.Name, found = eps.Labels[disv1beta1.LabelServiceName]
if !found {
return
}
obj, exists, err := e.serviceStore.Get(svc)
if err != nil {
level.Error(e.logger).Log("msg", "retrieving service failed", "err", err)
return
}
if !exists {
return
}
svc = obj.(*apiv1.Service)
tg.Labels = tg.Labels.Merge(serviceLabels(svc))
}