Use custom piped metrics registry instead of the default one

pkg/app/api/service/pipedservice/service.proto

@@ -165,7 +165,7 @@ message PingResponse {
 
 message ReportStatRequest {
     // Metrics byte sequence in OpenMetrics format.
-    bytes piped_stats = 1 [(validate.rules).bytes.min_len = 1];
+    bytes piped_stats = 1;
 }
 
 message ReportStatResponse {

pkg/app/piped/cmd/piped/piped.go

@@ -134,7 +134,7 @@ func (p *piped) run(ctx context.Context, t cli.Telemetry) (runErr error) {
 	}
 
 	// Register all metrics.
-	registerMetrics(cfg.PipedID)
+	registry := registerMetrics(cfg.PipedID)
 
 	// Initialize notifier and add piped events.
 	notifier, err := notifier.NewNotifier(cfg, t.Logger)
@@ -202,7 +202,7 @@ func (p *piped) run(ctx context.Context, t cli.Telemetry) (runErr error) {
 		admin.HandleFunc("/healthz", func(w http.ResponseWriter, r *http.Request) {
 			w.Write([]byte("ok"))
 		})
-		admin.Handle("/metrics", t.PrometheusMetricsHandler())
+		admin.Handle("/metrics", t.PrometheusMetricsHandlerFor(registry))
 
 		group.Go(func() error {
 			return admin.Run(ctx)
@@ -616,14 +616,20 @@ func (p *piped) insertLoginUserToPasswd(ctx context.Context) error {
 	return nil
 }
 
-func registerMetrics(pipedID string) {
-	r := prometheus.DefaultRegisterer
-	// TODO: Add piped version as label.
+func registerMetrics(pipedID string) *prometheus.Registry {
+	r := prometheus.NewRegistry()
 	wrapped := prometheus.WrapRegistererWith(
-		prometheus.Labels{"piped": pipedID},
+		prometheus.Labels{
+			"piped":         pipedID,
+			"piped_version": version.Get().Version,
+		},
 		r,
 	)
+	wrapped.Register(prometheus.NewGoCollector())
+	wrapped.Register(prometheus.NewProcessCollector(prometheus.ProcessCollectorOpts{}))
 
 	k8scloudprovidermetrics.Register(wrapped)
 	k8slivestatestoremetrics.Register(wrapped)
+
+	return r
 }

pkg/cli/BUILD.bazel

@@ -11,6 +11,7 @@ go_library(
     deps = [
         "//pkg/log:go_default_library",
         "//pkg/version:go_default_library",
+        "@com_github_prometheus_client_golang//prometheus:go_default_library",
         "@com_github_prometheus_client_golang//prometheus/promhttp:go_default_library",
         "@com_github_spf13_cobra//:go_default_library",
         "@com_github_spf13_pflag//:go_default_library",

pkg/cli/cmd.go

@@ -23,6 +23,7 @@ import (
 	"syscall"
 
 	"cloud.google.com/go/profiler"
+	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/spf13/cobra"
 	"go.uber.org/zap"
@@ -126,6 +127,16 @@ func (t Telemetry) PrometheusMetricsHandler() http.Handler {
 	return empty
 }
 
+func (t Telemetry) PrometheusMetricsHandlerFor(r *prometheus.Registry) http.Handler {
+	if t.Flags.Metrics {
+		return promhttp.HandlerFor(r, promhttp.HandlerOpts{})
+	}
+	var empty http.HandlerFunc = func(w http.ResponseWriter, r *http.Request) {
+		w.Write([]byte(""))
+	}
+	return empty
+}
+
 func extractServiceName(cmd *cobra.Command) string {
 	return strings.Replace(cmd.CommandPath(), " ", ".", -1)
 }