Make metrics registerer/gathererer replacable

Signed-off-by: Brad Davidson <brad.davidson@rancher.com>
cloudnativelabs · Oct 7, 2023 · aa107d6 · aa107d6
1 parent e6f668c
commit aa107d6
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Showing 4 changed files with 37 additions and 25 deletions.
diff --git a/pkg/controllers/netpol/network_policy_controller.go b/pkg/controllers/netpol/network_policy_controller.go
@@ -16,7 +16,6 @@ import (
 	"github.com/cloudnativelabs/kube-router/v2/pkg/options"
 	"github.com/cloudnativelabs/kube-router/v2/pkg/utils"
 	"github.com/coreos/go-iptables/iptables"
-	"github.com/prometheus/client_golang/prometheus"
 	"k8s.io/klog/v2"
 
 	v1core "k8s.io/api/core/v1"
@@ -845,8 +844,8 @@ func NewNetworkPolicyController(clientset kubernetes.Interface,
 
 	if config.MetricsEnabled {
 		// Register the metrics for this controller
-		prometheus.MustRegister(metrics.ControllerIptablesSyncTime)
-		prometheus.MustRegister(metrics.ControllerPolicyChainsSyncTime)
+		metrics.DefaultRegisterer.MustRegister(metrics.ControllerIptablesSyncTime)
+		metrics.DefaultRegisterer.MustRegister(metrics.ControllerPolicyChainsSyncTime)
 		npc.MetricsEnabled = true
 	}
 

diff --git a/pkg/controllers/proxy/network_services_controller.go b/pkg/controllers/proxy/network_services_controller.go
@@ -25,7 +25,6 @@ import (
 	"github.com/coreos/go-iptables/iptables"
 	"github.com/docker/docker/client"
 	"github.com/moby/ipvs"
-	"github.com/prometheus/client_golang/prometheus"
 	"github.com/vishvananda/netlink"
 	"github.com/vishvananda/netns"
 	api "k8s.io/api/core/v1"
@@ -2285,18 +2284,18 @@ func NewNetworkServicesController(clientset kubernetes.Interface,
 
 	if config.MetricsEnabled {
 		// Register the metrics for this controller
-		prometheus.MustRegister(metrics.ControllerIpvsServices)
-		prometheus.MustRegister(metrics.ControllerIpvsServicesSyncTime)
-		prometheus.MustRegister(metrics.ServiceBpsIn)
-		prometheus.MustRegister(metrics.ServiceBpsOut)
-		prometheus.MustRegister(metrics.ServiceBytesIn)
-		prometheus.MustRegister(metrics.ServiceBytesOut)
-		prometheus.MustRegister(metrics.ServiceCPS)
-		prometheus.MustRegister(metrics.ServicePacketsIn)
-		prometheus.MustRegister(metrics.ServicePacketsOut)
-		prometheus.MustRegister(metrics.ServicePpsIn)
-		prometheus.MustRegister(metrics.ServicePpsOut)
-		prometheus.MustRegister(metrics.ServiceTotalConn)
+		metrics.DefaultRegisterer.MustRegister(metrics.ControllerIpvsServices)
+		metrics.DefaultRegisterer.MustRegister(metrics.ControllerIpvsServicesSyncTime)
+		metrics.DefaultRegisterer.MustRegister(metrics.ServiceBpsIn)
+		metrics.DefaultRegisterer.MustRegister(metrics.ServiceBpsOut)
+		metrics.DefaultRegisterer.MustRegister(metrics.ServiceBytesIn)
+		metrics.DefaultRegisterer.MustRegister(metrics.ServiceBytesOut)
+		metrics.DefaultRegisterer.MustRegister(metrics.ServiceCPS)
+		metrics.DefaultRegisterer.MustRegister(metrics.ServicePacketsIn)
+		metrics.DefaultRegisterer.MustRegister(metrics.ServicePacketsOut)
+		metrics.DefaultRegisterer.MustRegister(metrics.ServicePpsIn)
+		metrics.DefaultRegisterer.MustRegister(metrics.ServicePpsOut)
+		metrics.DefaultRegisterer.MustRegister(metrics.ServiceTotalConn)
 		nsc.MetricsEnabled = true
 	}
 

diff --git a/pkg/controllers/routing/network_routes_controller.go b/pkg/controllers/routing/network_routes_controller.go
@@ -23,7 +23,6 @@ import (
 	"github.com/coreos/go-iptables/iptables"
 	gobgpapi "github.com/osrg/gobgp/v3/api"
 	gobgp "github.com/osrg/gobgp/v3/pkg/server"
-	"github.com/prometheus/client_golang/prometheus"
 	"github.com/vishvananda/netlink"
 	v1core "k8s.io/api/core/v1"
 	"k8s.io/client-go/kubernetes"
@@ -1407,11 +1406,11 @@ func NewNetworkRoutingController(clientset kubernetes.Interface,
 	nrc := NetworkRoutingController{ipsetMutex: ipsetMutex}
 	if kubeRouterConfig.MetricsEnabled {
 		// Register the metrics for this controller
-		prometheus.MustRegister(metrics.ControllerBGPadvertisementsReceived)
-		prometheus.MustRegister(metrics.ControllerBGPadvertisementsSent)
-		prometheus.MustRegister(metrics.ControllerBGPInternalPeersSyncTime)
-		prometheus.MustRegister(metrics.ControllerBPGpeers)
-		prometheus.MustRegister(metrics.ControllerRoutesSyncTime)
+		metrics.DefaultRegisterer.MustRegister(metrics.ControllerBGPadvertisementsReceived)
+		metrics.DefaultRegisterer.MustRegister(metrics.ControllerBGPadvertisementsSent)
+		metrics.DefaultRegisterer.MustRegister(metrics.ControllerBGPInternalPeersSyncTime)
+		metrics.DefaultRegisterer.MustRegister(metrics.ControllerBPGpeers)
+		metrics.DefaultRegisterer.MustRegister(metrics.ControllerRoutesSyncTime)
 		nrc.MetricsEnabled = true
 	}
 

diff --git a/pkg/metrics/metrics_controller.go b/pkg/metrics/metrics_controller.go
@@ -21,6 +21,16 @@ const (
 	namespace                 = "kube_router"
 )
 
+var (
+	// DefaultRegisterer and DefaultGatherer are the implementations of the
+	// prometheus Registerer and Gatherer interfaces that all metrics operations
+	// will use. They are variables so that packages that embed this library can
+	// replace them at runtime, instead of having to pass around specific
+	// registries.
+	DefaultRegisterer = prometheus.DefaultRegisterer
+	DefaultGatherer   = prometheus.DefaultGatherer
+)
+
 var (
 	// BuildInfo Expose version and other build information
 	BuildInfo = prometheus.NewGaugeVec(prometheus.GaugeOpts{
@@ -159,6 +169,11 @@ type Controller struct {
 	MetricsPort uint16
 }
 
+// Handler returns a http.Handler for the default registerer and gatherer
+func Handler() http.Handler {
+	return promhttp.InstrumentMetricHandler(DefaultRegisterer, promhttp.HandlerFor(DefaultGatherer, promhttp.HandlerOpts{}))
+}
+
 // Run prometheus metrics controller
 func (mc *Controller) Run(healthChan chan<- *healthcheck.ControllerHeartbeat, stopCh <-chan struct{},
 	wg *sync.WaitGroup) {
@@ -168,16 +183,16 @@ func (mc *Controller) Run(healthChan chan<- *healthcheck.ControllerHeartbeat, st
 
 	// register metrics for this controller
 	BuildInfo.WithLabelValues(runtime.Version(), version.Version).Set(1)
-	prometheus.MustRegister(BuildInfo)
-	prometheus.MustRegister(ControllerIpvsMetricsExportTime)
+	DefaultRegisterer.MustRegister(BuildInfo)
+	DefaultRegisterer.MustRegister(ControllerIpvsMetricsExportTime)
 
 	srv := &http.Server{
 		Addr:              ":" + strconv.Itoa(int(mc.MetricsPort)),
 		Handler:           http.DefaultServeMux,
 		ReadHeaderTimeout: 5 * time.Second}
 
 	// add prometheus handler on metrics path
-	http.Handle(mc.MetricsPath, promhttp.Handler())
+	http.Handle(mc.MetricsPath, Handler())
 
 	go func() {
 		if err := srv.ListenAndServe(); err != nil {