[extension/apikeyauth] Set user-agent (#901)

Set User-Agent based on collector instead of using go-elasticsearch default UA

Author: carsonip

extension/apikeyauthextension/authenticator.go

@@ -27,10 +27,12 @@ import (
 	"fmt"
 	"hash/fnv"
 	"net/http"
+	"runtime"
 	"strings"
 
 	"go.opentelemetry.io/collector/client"
 	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/extension"
 	"go.opentelemetry.io/collector/extension/extensionauth"
 	"golang.org/x/crypto/pbkdf2"
 	"google.golang.org/genproto/googleapis/rpc/errdetails"
@@ -91,13 +93,14 @@ func (a *authData) GetAttributeNames() []string {
 type authenticator struct {
 	config            *Config
 	telemetrySettings component.TelemetrySettings
+	userAgent         string
 
 	esClient *elasticsearch.TypedClient
 	cache    freelru.Cache[string, *cacheEntry]
 	salt     [16]byte // used for deriving keys from API Keys
 }
 
-func newAuthenticator(cfg *Config, set component.TelemetrySettings) (*authenticator, error) {
+func newAuthenticator(cfg *Config, set extension.Settings) (*authenticator, error) {
 	cache, err := freelru.NewSharded[string, *cacheEntry](cfg.Cache.Capacity, func(key string) uint32 {
 		h := fnv.New32a()
 		h.Write([]byte(key))
@@ -108,9 +111,18 @@ func newAuthenticator(cfg *Config, set component.TelemetrySettings) (*authentica
 	}
 	cache.SetLifetime(cfg.Cache.TTL)
 
+	userAgent := fmt.Sprintf(
+		"%s/%s (%s/%s)",
+		set.BuildInfo.Description,
+		set.BuildInfo.Version,
+		runtime.GOOS,
+		runtime.GOARCH,
+	)
+
 	authenticator := &authenticator{
 		config:            cfg,
-		telemetrySettings: set,
+		telemetrySettings: set.TelemetrySettings,
+		userAgent:         userAgent,
 		cache:             cache,
 	}
 	if _, err := rand.Read(authenticator.salt[:]); err != nil {
@@ -126,6 +138,9 @@ func (a *authenticator) Start(ctx context.Context, host component.Host) error {
 	}
 	esClient, err := elasticsearch.NewTypedClient(elasticsearch.Config{
 		Addresses: []string{a.config.Endpoint},
+		Header: map[string][]string{
+			"User-Agent": {a.userAgent},
+		},
 		Transport: httpClient.Transport,
 		Instrumentation: elasticsearch.NewOpenTelemetryInstrumentation(
 			a.telemetrySettings.TracerProvider, false,

extension/apikeyauthextension/authenticator_test.go

@@ -24,6 +24,7 @@ import (
 	"fmt"
 	"net/http"
 	"net/http/httptest"
+	"strings"
 	"testing"
 	"time"
 
@@ -33,9 +34,12 @@ import (
 	"github.com/stretchr/testify/require"
 	"go.opentelemetry.io/collector/client"
 	"go.opentelemetry.io/collector/component/componenttest"
+	"go.opentelemetry.io/collector/extension/extensiontest"
 	"google.golang.org/genproto/googleapis/rpc/errdetails"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
+
+	"github.com/elastic/opentelemetry-collector-components/extension/apikeyauthextension/internal/metadata"
 )
 
 const user = "test"
@@ -196,6 +200,21 @@ func TestAuthenticator_Caching(t *testing.T) {
 	assert.EqualError(t, err, `rpc error: code = Unauthenticated desc = API Key "id2" unauthorized`)
 }
 
+func TestAuthenticator_UserAgent(t *testing.T) {
+	srv := newMockElasticsearch(t, func(w http.ResponseWriter, r *http.Request) {
+		wantPrefix := "OpenTelemetry Collector/latest ("
+		userAgent := r.Header.Get("User-Agent")
+		assert.Truef(t, strings.HasPrefix(userAgent, wantPrefix), "want prefix %s; got %s", wantPrefix, userAgent)
+		assert.NoError(t, json.NewEncoder(w).Encode(successfulResponse))
+	})
+
+	authenticator := newTestAuthenticator(t, srv, createDefaultConfig().(*Config))
+	_, err := authenticator.Authenticate(context.Background(), map[string][]string{
+		"Authorization": {"ApiKey " + base64.StdEncoding.EncodeToString([]byte("id:secret"))},
+	})
+	assert.NoError(t, err)
+}
+
 func TestAuthenticator_ErrorWithDetails(t *testing.T) {
 	for name, testcase := range map[string]struct {
 		setup            func(*testing.T) (*authenticator, map[string][]string)
@@ -483,7 +502,7 @@ func BenchmarkAuthenticator(b *testing.B) {
 
 func newTestAuthenticator(t testing.TB, srv *httptest.Server, config *Config) *authenticator {
 	config.Endpoint = srv.URL
-	auth, err := newAuthenticator(config, componenttest.NewNopTelemetrySettings())
+	auth, err := newAuthenticator(config, extensiontest.NewNopSettings(metadata.Type))
 	require.NoError(t, err)
 
 	err = auth.Start(context.Background(), componenttest.NewNopHost())

extension/apikeyauthextension/factory.go

@@ -36,5 +36,5 @@ func NewFactory() extension.Factory {
 }
 
 func createExtension(_ context.Context, set extension.Settings, cfg component.Config) (extension.Extension, error) {
-	return newAuthenticator(cfg.(*Config), set.TelemetrySettings)
+	return newAuthenticator(cfg.(*Config), set)
 }