export prometheus metrics on :9090

cmd/caddy/main.go

@@ -3,9 +3,12 @@ package main
 import (
 	"fmt"
 	"net/http"
+	"os"
 	"time"
 
 	"github.com/caddyserver/ingress/internal/controller"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/sirupsen/logrus"
 	v1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/util/wait"
@@ -48,36 +51,40 @@ func main() {
 	// start ingress controller
 	c := controller.NewCaddyController(kubeClient, restClient, cfg)
 
-	// create http server to expose controller health metrics
-	healthPort := 9090
-	go startMetricsServer(healthPort)
+	reg := prometheus.NewRegistry()
 
-	logrus.Info("Starting the caddy ingress controller")
+	reg.MustRegister(prometheus.NewGoCollector())
+	reg.MustRegister(prometheus.NewProcessCollector(prometheus.ProcessCollectorOpts{
+		PidFn:        func() (int, error) { return os.Getpid(), nil },
+		ReportErrors: true,
+	}))
+
+	// create http server to expose controller health metrics
+	go startMetricsServer(reg)
 
 	// start the ingress controller
 	stopCh := make(chan struct{}, 1)
 	defer close(stopCh)
 
+	logrus.Info("Starting the caddy ingress controller")
 	go c.Run(stopCh)
 
 	select {}
 }
 
-type healthChecker struct{}
-
-func (h *healthChecker) Name() string {
-	return "caddy-ingress-controller"
-}
-
-func (h *healthChecker) Check(_ *http.Request) error {
-	return nil
-}
-
-func startMetricsServer(port int) {
+func startMetricsServer(reg *prometheus.Registry) {
 	mux := http.NewServeMux()
+	mux.Handle(
+		"/metrics",
+		promhttp.InstrumentMetricHandler(
+			reg,
+			promhttp.HandlerFor(reg, promhttp.HandlerOpts{}),
+		),
+	)
 
+	logrus.Info("Exporting metrics on :9090")
 	server := &http.Server{
-		Addr:              fmt.Sprintf(":%v", port),
+		Addr:              fmt.Sprintf(":%v", 9090),
 		Handler:           mux,
 		ReadTimeout:       10 * time.Second,
 		ReadHeaderTimeout: 10 * time.Second,

go.mod

@@ -9,6 +9,7 @@ require (
 	github.com/mholt/certmagic v0.5.1
 	github.com/opencontainers/go-digest v1.0.0-rc1 // indirect
 	github.com/pkg/errors v0.8.1
+	github.com/prometheus/client_golang v0.9.2
 	github.com/sirupsen/logrus v1.2.0
 	golang.org/x/time v0.0.0-20190308202827-9d24e82272b4 // indirect
 	google.golang.org/grpc v1.20.1 // indirect

internal/controller/controller.go

@@ -72,7 +72,7 @@ func NewCaddyController(kubeClient *kubernetes.Clientset, restClient rest.Interf
 	controller.podInfo = podInfo
 
 	// load caddy config from file if mounted with config map
-	var caddyCfgMap caddy.Config
+	var caddyCfgMap *caddy.Config
 	cfgPath := "/etc/caddy/config.json"
 	if _, err := os.Stat(cfgPath); !os.IsNotExist(err) {
 		controller.usingConfigMap = true
@@ -104,7 +104,7 @@ func NewCaddyController(kubeClient *kubernetes.Clientset, restClient rest.Interf
 	controller.informer = informer
 
 	// setup store to keep track of resources
-	controller.resourceStore = store.NewStore(controller.kubeClient, podInfo.Namespace, cfg, &caddyCfgMap)
+	controller.resourceStore = store.NewStore(controller.kubeClient, podInfo.Namespace, cfg, caddyCfgMap)
 
 	// attempt to do initial sync of status addresses with ingresses
 	controller.dispatchSync()

kubernetes/generated/deployment.yaml

@@ -63,6 +63,8 @@ spec:
             containerPort: 80
           - name: https
             containerPort: 443
+          - name: metrics
+            containerPort: 9090
         env:
           - name: POD_NAME
             valueFrom:

kubernetes/generated/metricsservice.yaml

@@ -0,0 +1,14 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: metrics
+  namespace: caddy-system
+  labels:
+    app: caddy-ingress-controller
+spec:
+  ports:
+    - name: metrics
+      port: 80
+      protocol: TCP
+      targetPort: metrics
+  type: "ClusterIP"

skaffold.yaml

@@ -15,4 +15,6 @@ deploy:
     - kubernetes/generated/clusterrolebinding.yaml
     - kubernetes/generated/deployment.yaml
     - kubernetes/generated/serviceaccount.yaml
+    - kubernetes/generated/metricsservice.yaml
+    # - kubernetes/generated/configmap.yaml
     # - kubernetes/generated/loadbalancer.yaml