Expose prometheus metrics for BotKube

cmd/botkube/main.go

@@ -2,15 +2,21 @@ package main
 
 import (
 	"fmt"
+	"os"
 
 	"github.com/infracloudio/botkube/pkg/bot"
 	"github.com/infracloudio/botkube/pkg/config"
 	"github.com/infracloudio/botkube/pkg/controller"
 	log "github.com/infracloudio/botkube/pkg/logging"
+	"github.com/infracloudio/botkube/pkg/metrics"
 	"github.com/infracloudio/botkube/pkg/notify"
 	"github.com/infracloudio/botkube/pkg/utils"
 )
 
+const (
+	defaultMetricsPort = "2112"
+)
+
 func main() {
 	log.Logger.Info("Starting controller")
 	Config, err := config.New()
@@ -30,6 +36,13 @@ func main() {
 		go mb.Start()
 	}
 
+	// Prometheus metrics
+	metricsPort, exists := os.LookupEnv("METRICS_PORT")
+	if !exists {
+		metricsPort = defaultMetricsPort
+	}
+	go metrics.ServeMetrics(metricsPort)
+
 	// List notifiers
 	var notifiers []notify.Notifier
 	if Config.Communications.Slack.Enabled {

go.mod

@@ -31,7 +31,7 @@ require (
 	github.com/onsi/ginkgo v1.10.2 // indirect
 	github.com/pborman/uuid v1.2.0 // indirect
 	github.com/pelletier/go-toml v1.5.0 // indirect
-	github.com/pkg/errors v0.8.1 // indirect
+	github.com/prometheus/client_golang v1.2.1
 	github.com/sirupsen/logrus v1.4.2
 	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/stretchr/objx v0.2.0 // indirect
@@ -42,7 +42,6 @@ require (
 	go.uber.org/zap v1.10.0 // indirect
 	golang.org/x/crypto v0.0.0-20191002192127-34f69633bfdc // indirect
 	golang.org/x/net v0.0.0-20191009170851-d66e71096ffb // indirect
-	golang.org/x/sys v0.0.0-20191009170203-06d7bd2c5f4f // indirect
 	golang.org/x/time v0.0.0-20190921001708-c4c64cad1fd0 // indirect
 	google.golang.org/appengine v1.6.5 // indirect
 	gopkg.in/asn1-ber.v1 v1.0.0-20181015200546-f715ec2f112d // indirect

helm/botkube/templates/deployment.yaml

@@ -42,6 +42,8 @@ spec:
               value: {{ .Values.logLevel | quote }}
             - name: BOTKUBE_VERSION
               value: {{ .Chart.Version }}
+            - name: METRICS_PORT
+              value: {{ .Values.service.targetPort | quote }} 
         {{- if .Values.extraEnv }}
           {{- range $name, $value := .Values.extraEnv }}
             - name: {{ $name }}

helm/botkube/templates/service.yaml

@@ -0,0 +1,20 @@
+{{- if .Values.serviceMonitor.enabled }}
+apiVersion: v1
+kind: Service
+metadata:
+  name: {{ include "botkube.fullname" . }}
+  labels: 
+    app.kubernetes.io/name: {{ include "botkube.name" . }}
+    helm.sh/chart: {{ include "botkube.chart" . }}
+    app.kubernetes.io/instance: {{ .Release.Name }}
+    app.kubernetes.io/managed-by: {{ .Release.Service }}  
+    app: botkube
+spec:
+  type: ClusterIP
+  ports:
+  - name: {{ .Values.service.name }}
+    port: {{ .Values.service.port }}
+    targetPort: {{ .Values.service.targetPort }}
+  selector:
+    app: botkube 
+{{- end }}

helm/botkube/templates/servicemonitor.yaml

@@ -0,0 +1,31 @@
+{{- if .Values.serviceMonitor.enabled }}
+apiVersion: monitoring.coreos.com/v1
+kind: ServiceMonitor
+metadata:
+  name: {{ template "botkube.fullname" . }}
+  labels:
+    app.kubernetes.io/name: {{ include "botkube.name" . }}
+    helm.sh/chart: {{ include "botkube.chart" . }}
+    app.kubernetes.io/instance: {{ .Release.Name }}
+    app.kubernetes.io/managed-by: {{ .Release.Service }}
+    {{- if .Values.serviceMonitor.labels }}
+    {{- toYaml .Values.serviceMonitor.labels | nindent 4 }}
+    {{- end }}
+
+spec:
+  endpoints:
+  - interval: {{ .Values.serviceMonitor.interval }}
+    port: {{ .Values.serviceMonitor.port }}
+    path: {{ .Values.serviceMonitor.path }}
+  selector:
+    matchLabels:
+      app.kubernetes.io/name: {{ include "botkube.name" . }}
+      helm.sh/chart: {{ include "botkube.chart" . }}
+      app.kubernetes.io/instance: {{ .Release.Name }}
+      app.kubernetes.io/managed-by: {{ .Release.Service }}
+      component: controller
+      app: botkube
+  namespaceSelector:
+    matchNames:
+      - {{ .Release.Namespace }}
+{{- end }}

helm/botkube/values.yaml

@@ -250,6 +250,21 @@ config:
     # Set false to disable upgrade notification
     upgradeNotifier: true
 
+service:
+  name: metrics
+  port: 2112
+  targetPort: 2112  
+
+serviceMonitor:
+  ## If true, a ServiceMonitor CR is created for a botkube
+  ##  https://github.com/coreos/prometheus-operator/blob/master/Documentation/api.md#servicemonitor
+  ##
+  enabled: false
+  interval: 10s
+  path: /metrics
+  port: metrics
+  labels: {} 
+
 resources: {}
   # We usually recommend not to specify default resources and to leave this as a conscious
   # choice for the user. This also increases chances charts run on environments with little

pkg/metrics/metrics.go

@@ -0,0 +1,12 @@
+package metrics
+
+import (
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+	"net/http"
+)
+
+// ServeMetrics exposes metrics in Prometheus format
+func ServeMetrics(metricsPort string) {
+	http.Handle("/metrics", promhttp.Handler())
+	http.ListenAndServe(":"+metricsPort, nil)
+}