fix(metrics): create another endpoint for prometheus

Make the resources that are updated by the catalog operator be served
from there too (and remove them from olm). Update the prometheus http
handler to use the non-deprecated version, and do it on port 8081.

Also, actually serve the health check in OLM.

Author: Jeff Peeler

cmd/catalog/main.go

@@ -8,11 +8,13 @@ import (
 	"strings"
 	"time"
 
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	log "github.com/sirupsen/logrus"
 	v1 "k8s.io/api/core/v1"
 
 	"github.com/operator-framework/operator-lifecycle-manager/pkg/controller/operators/catalog"
 	"github.com/operator-framework/operator-lifecycle-manager/pkg/lib/signals"
+	"github.com/operator-framework/operator-lifecycle-manager/pkg/metrics"
 	olmversion "github.com/operator-framework/operator-lifecycle-manager/pkg/version"
 )
 
@@ -45,6 +47,10 @@ var (
 	version = flag.Bool("version", false, "displays olm version")
 )
 
+func init() {
+	metrics.RegisterCatalog()
+}
+
 func main() {
 	stopCh := signals.SetupSignalHandler()
 
@@ -87,6 +93,10 @@ func main() {
 		log.Panicf("error configuring operator: %s", err.Error())
 	}
 
+	http.Handle("/metrics", promhttp.Handler())
+	go http.ListenAndServe(":8081", nil)
+
 	_, done := catalogOperator.Run(stopCh)
 	<-done
 }
+

cmd/olm/main.go

@@ -8,7 +8,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	log "github.com/sirupsen/logrus"
 	v1 "k8s.io/api/core/v1"
 
@@ -45,7 +45,7 @@ var (
 )
 
 func init() {
-	metrics.Register()
+	metrics.RegisterOLM()
 }
 
 // main function - entrypoint to OLM operator
@@ -100,12 +100,11 @@ func main() {
 	http.HandleFunc("/healthz", func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)
 	})
-	// TODO: both of the following require vendor updates (add k8s.io/apiserver and update prometheus)
-	//healthz.InstallHandler(mux) //(less code)
-	//mux.Handle("/metrics", promhttp.Handler()) //other form is deprecated
-	http.Handle("/metrics", prometheus.Handler())
 	go http.ListenAndServe(":8080", nil)
 
+	http.Handle("/metrics", promhttp.Handler())
+	go http.ListenAndServe(":8081", nil)
+
 	_, done := operator.Run(stopCh)
 	<-done
 }

pkg/metrics/metrics.go

@@ -129,15 +129,18 @@ var (
 	CSVUpgradeCount = prometheus.NewCounter(
 		prometheus.CounterOpts{
 			Name: "csv_upgrade_count",
-			Help: "Monotonic count of catalog sources",
+			Help: "Monotonic count of CSV upgrades",
 		},
 	)
 )
 
-func Register() {
+func RegisterOLM() {
 	prometheus.MustRegister(csvCount)
+	prometheus.MustRegister(CSVUpgradeCount)
+}
+
+func RegisterCatalog() {
 	prometheus.MustRegister(installPlanCount)
 	prometheus.MustRegister(subscriptionCount)
 	prometheus.MustRegister(catalogSourceCount)
-	prometheus.MustRegister(CSVUpgradeCount)
 }