VictoriaMetrics/lib/promscrape/discovery/kubernetes/api.go

78 lines
2.6 KiB
Go

package kubernetes
import (
"fmt"
"net"
"os"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/promauth"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/promscrape/discoveryutils"
)
// apiConfig contains config for API server
type apiConfig struct {
client *discoveryutils.Client
namespaces []string
selectors []Selector
}
var configMap = discoveryutils.NewConfigMap()
func getAPIConfig(sdc *SDConfig, baseDir string) (*apiConfig, error) {
v, err := configMap.Get(sdc, func() (interface{}, error) { return newAPIConfig(sdc, baseDir) })
if err != nil {
return nil, err
}
return v.(*apiConfig), nil
}
func newAPIConfig(sdc *SDConfig, baseDir string) (*apiConfig, error) {
ac, err := promauth.NewConfig(baseDir, sdc.BasicAuth, sdc.BearerToken, sdc.BearerTokenFile, sdc.TLSConfig)
if err != nil {
return nil, fmt.Errorf("cannot parse auth config: %s", err)
}
apiServer := sdc.APIServer
if len(apiServer) == 0 {
// Assume we run at k8s pod.
// Discover apiServer and auth config according to k8s docs.
// See https://kubernetes.io/docs/reference/access-authn-authz/service-accounts-admin/#service-account-admission-controller
host := os.Getenv("KUBERNETES_SERVICE_HOST")
port := os.Getenv("KUBERNETES_SERVICE_PORT")
if len(host) == 0 {
return nil, fmt.Errorf("cannot find KUBERNETES_SERVICE_HOST env var; it must be defined when running in k8s; " +
"probably, `kubernetes_sd_config->api_server` is missing in Prometheus configs?")
}
if len(port) == 0 {
return nil, fmt.Errorf("cannot find KUBERNETES_SERVICE_PORT env var; it must be defined when running in k8s; "+
"KUBERNETES_SERVICE_HOST=%q", host)
}
apiServer = "https://" + net.JoinHostPort(host, port)
tlsConfig := promauth.TLSConfig{
CAFile: "/var/run/secrets/kubernetes.io/serviceaccount/ca.crt",
}
acNew, err := promauth.NewConfig("/", nil, "", "/var/run/secrets/kubernetes.io/serviceaccount/token", &tlsConfig)
if err != nil {
return nil, fmt.Errorf("cannot initialize service account auth: %s; probably, `kubernetes_sd_config->api_server` is missing in Prometheus configs?", err)
}
ac = acNew
}
client, err := discoveryutils.NewClient(apiServer, ac)
if err != nil {
return nil, fmt.Errorf("cannot create HTTP client for %q: %s", apiServer, err)
}
cfg := &apiConfig{
client: client,
namespaces: sdc.Namespaces.Names,
selectors: sdc.Selectors,
}
return cfg, nil
}
func getAPIResponse(cfg *apiConfig, role, path string) ([]byte, error) {
query := joinSelectors(role, cfg.namespaces, cfg.selectors)
if len(query) > 0 {
path += "?" + query
}
return cfg.client.GetAPIResponse(path)
}