Update http header User-Agent in k8s and swarm discovery. (#7614)

* discovery: update k8s and swarm user agent.

Signed-off-by: johncming <johncming@yahoo.com>

discovery/dockerswarm/dockerswarm.go

@@ -24,6 +24,7 @@ import (
 	"github.com/go-kit/kit/log"
 	config_util "github.com/prometheus/common/config"
 	"github.com/prometheus/common/model"
+	"github.com/prometheus/common/version"
 
 	"github.com/prometheus/prometheus/discovery/refresh"
 	"github.com/prometheus/prometheus/discovery/targetgroup"
@@ -33,6 +34,8 @@ const (
 	swarmLabel = model.MetaLabelPrefix + "dockerswarm_"
 )
 
+var userAgent = fmt.Sprintf("Prometheus/%s", version.Version)
+
 // DefaultSDConfig is the default Docker Swarm SD configuration.
 var DefaultSDConfig = SDConfig{
 	RefreshInterval: model.Duration(60 * time.Second),
@@ -116,6 +119,9 @@ func NewDiscovery(conf *SDConfig, logger log.Logger) (*Discovery, error) {
 				Timeout:   time.Duration(conf.RefreshInterval),
 			}),
 			client.WithScheme(hostURL.Scheme),
+			client.WithHTTPHeaders(map[string]string{
+				"User-Agent": userAgent,
+			}),
 		)
 	}
 

discovery/kubernetes/kubernetes.go

@@ -15,6 +15,7 @@ package kubernetes
 
 import (
 	"context"
+	"fmt"
 	"reflect"
 	"strings"
 	"sync"
@@ -36,6 +37,7 @@ import (
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/cache"
 
+	"github.com/prometheus/common/version"
 	"github.com/prometheus/prometheus/discovery/targetgroup"
 )
 
@@ -49,6 +51,8 @@ const (
 )
 
 var (
+	// Http header
+	userAgent = fmt.Sprintf("Prometheus/%s", version.Version)
 	// Custom events metric
 	eventCount = prometheus.NewCounterVec(
 		prometheus.CounterOpts{
@@ -262,7 +266,7 @@ func New(l log.Logger, conf *SDConfig) (*Discovery, error) {
 		}
 	}
 
-	kcfg.UserAgent = "Prometheus/discovery"
+	kcfg.UserAgent = userAgent
 
 	c, err := kubernetes.NewForConfig(kcfg)
 	if err != nil {