VictoriaMetrics/lib/promscrape/discovery/kubernetes/service.go
Aliaksandr Valialkin 8fc29ffc67 lib/promscrape/discovery/kubernetes: use a single watcher per apiURL
Previously multiple scrape jobs could create multiple watchers for the same apiURL. Now only a single watcher is used.
This should reduce load on Kubernetes API server when many scrape job configs use Kubernetes service discovery.
2021-03-11 17:04:14 +02:00

100 lines
2.7 KiB
Go

package kubernetes
import (
"encoding/json"
"fmt"
"io"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape/discoveryutils"
)
func (s *Service) key() string {
return s.Metadata.key()
}
func parseServiceList(r io.Reader) (map[string]object, ListMeta, error) {
var sl ServiceList
d := json.NewDecoder(r)
if err := d.Decode(&sl); err != nil {
return nil, sl.Metadata, fmt.Errorf("cannot unmarshal ServiceList: %w", err)
}
objectsByKey := make(map[string]object)
for _, s := range sl.Items {
objectsByKey[s.key()] = s
}
return objectsByKey, sl.Metadata, nil
}
func parseService(data []byte) (object, error) {
var s Service
if err := json.Unmarshal(data, &s); err != nil {
return nil, err
}
return &s, nil
}
// ServiceList is k8s service list.
//
// See https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.17/#servicelist-v1-core
type ServiceList struct {
Metadata ListMeta
Items []*Service
}
// Service is k8s service.
//
// See https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.17/#service-v1-core
type Service struct {
Metadata ObjectMeta
Spec ServiceSpec
}
// ServiceSpec is k8s service spec.
//
// See https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.17/#servicespec-v1-core
type ServiceSpec struct {
ClusterIP string
ExternalName string
Type string
Ports []ServicePort
}
// ServicePort is k8s service port.
//
// See https://kubernetes.io/docs/reference/generated/kubernetes-api/v1.17/#serviceport-v1-core
type ServicePort struct {
Name string
Protocol string
Port int
}
// getTargetLabels returns labels for each port of the given s.
//
// See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#service
func (s *Service) getTargetLabels(aw *apiWatcher) []map[string]string {
host := fmt.Sprintf("%s.%s.svc", s.Metadata.Name, s.Metadata.Namespace)
var ms []map[string]string
for _, sp := range s.Spec.Ports {
addr := discoveryutils.JoinHostPort(host, sp.Port)
m := map[string]string{
"__address__": addr,
"__meta_kubernetes_service_port_name": sp.Name,
"__meta_kubernetes_service_port_protocol": sp.Protocol,
}
s.appendCommonLabels(m)
ms = append(ms, m)
}
return ms
}
func (s *Service) appendCommonLabels(m map[string]string) {
m["__meta_kubernetes_namespace"] = s.Metadata.Namespace
m["__meta_kubernetes_service_name"] = s.Metadata.Name
m["__meta_kubernetes_service_type"] = s.Spec.Type
if s.Spec.Type != "ExternalName" {
m["__meta_kubernetes_service_cluster_ip"] = s.Spec.ClusterIP
} else {
m["__meta_kubernetes_service_external_name"] = s.Spec.ExternalName
}
s.Metadata.registerLabelsAndAnnotations("__meta_kubernetes_service", m)
}