pkg/generator: Generate all manifests needed for Prometheus integration

Author: etiennecoutaud

Gopkg.lock

@@ -6,6 +6,10 @@
   name = "github.com/spf13/cobra"
   version = "0.0.2"
 
+[[override]]
+  name = "github.com/prometheus/client_golang"
+  version = "0.8.0"
+
 [[override]]
   name = "k8s.io/api"
   version = "kubernetes-1.9.3"

Gopkg.toml

@@ -56,6 +56,10 @@ $ kubectl create -f deploy/rbac.yaml
 $ kubectl create -f deploy/crd.yaml
 $ kubectl create -f deploy/operator.yaml
 
+# Monitor the app-operator using prometheus and serviceMonitor CRD
+$ kubectl create -f deploy/service.yaml
+$ kubectl create -f deploy/serviceMonitor.yaml
+
 # By default, creating a custom resource (App) triggers the app-operator to deploy a busybox pod
 $ kubectl create -f deploy/cr.yaml
 
@@ -68,6 +72,8 @@ busy-box   1/1       Running   0          50s
 $ kubectl delete -f deploy/cr.yaml
 $ kubectl delete -f deploy/operator.yaml
 $ kubectl delete -f deploy/rbac.yaml
+$ kubectl delete -f deploy/service.yaml
+$ kubectl delete -f deploy.serviceMonitor.yaml
 ```
 
 To learn more about the operator-sdk, see the [user guide][guide].

README.md

@@ -33,6 +33,8 @@ const operatorYamlTmpl = `apiVersion: apps/v1
 kind: Deployment
 metadata:
   name: {{.ProjectName}}
+  labels:
+    name: {{.ProjectName}}
 spec:
   replicas: 1
   selector:
@@ -46,6 +48,9 @@ spec:
       containers:
         - name: {{.ProjectName}}
           image: {{.Image}}
+          ports:
+          - containerPort: 9090
+            name: metrics
           command:
           - {{.ProjectName}}
           imagePullPolicy: Always
@@ -109,3 +114,31 @@ kind: "{{.Kind}}"
 metadata:
   name: "example"
 `
+
+const serviceYamlTmpl = `apiVersion: v1
+kind: Service
+metadata:
+  name: {{.ProjectName}}
+  labels:
+    name: {{.ProjectName}}
+spec:
+  selector:
+    name: {{.ProjectName}}
+  ports:
+  - protocol: TCP
+    targetPort: metrics
+    port: 9090
+    name: metrics`
+
+const serviceMonitorYamlTmpl = `apiVersion: monitoring.coreos.com/v1
+kind: ServiceMonitor
+metadata:
+  name: {{.ProjectName}}
+  labels:
+    name: {{.ProjectName}}
+spec:
+  selector:
+    matchLabels:
+      name: {{.ProjectName}}
+  endpoints:
+  - port: metrics`

pkg/generator/deploy_tmpl.go

@@ -22,10 +22,12 @@ import (
 )
 
 const (
-	crdTmplName      = "deploy/crd.yaml"
-	operatorTmplName = "deploy/operator.yaml"
-	rbacTmplName     = "deploy/rbac.yaml"
-	crTmplName       = "deploy/cr.yaml"
+	crdTmplName            = "deploy/crd.yaml"
+	operatorTmplName       = "deploy/operator.yaml"
+	rbacTmplName           = "deploy/rbac.yaml"
+	crTmplName             = "deploy/cr.yaml"
+	serviceTmplName        = "deploy/service.yaml"
+	serviceMonitorTmplName = "deploy/serviceMonitor.yaml"
 )
 
 // CRDYaml contains data needed to generate deploy/crd.yaml
@@ -77,6 +79,47 @@ func renderOperatorYaml(w io.Writer, projectName, image string) error {
 	return t.Execute(w, o)
 }
 
+// ServiceYaml contains all the customized data needed to generate deploy/service.yaml for a new operator
+// This service will be monitor by prometheus
+// when pairing with serviceYamlTmpl template.
+type ServiceYaml struct {
+	ProjectName string
+}
+
+// renderServiceYaml generates deploy/service.yaml.
+func renderServiceYaml(w io.Writer, projectName string) error {
+	t := template.New(serviceTmplName)
+	t, err := t.Parse(serviceYamlTmpl)
+	if err != nil {
+		return fmt.Errorf("Failed to parse service yaml template: %v", err)
+	}
+
+	s := ServiceYaml{
+		ProjectName: projectName,
+	}
+	return t.Execute(w, s)
+}
+
+// ServiceMonitorYaml contains all the customized data needed to generate deploy/serviceMonitor.yaml for a new operator
+// when pairing with serviceMonitorYamlTmpl template.
+type ServiceMonitorYaml struct {
+	ProjectName string
+}
+
+// renderServiceYaml generates deploy/service.yaml.
+func renderServiceMonitorYaml(w io.Writer, projectName string) error {
+	t := template.New(serviceMonitorTmplName)
+	t, err := t.Parse(serviceMonitorYamlTmpl)
+	if err != nil {
+		return fmt.Errorf("Failed to parse serviceMonitor yaml template: %v", err)
+	}
+
+	s := ServiceYaml{
+		ProjectName: projectName,
+	}
+	return t.Execute(w, s)
+}
+
 // RBACYaml contains all the customized data needed to generate deploy/rbac.yaml for a new operator
 // when pairing with rbacYamlTmpl template.
 type RBACYaml struct {

pkg/generator/gen_deploy.go

@@ -24,6 +24,8 @@ const operatorYamlExp = `apiVersion: apps/v1
 kind: Deployment
 metadata:
   name: app-operator
+  labels:
+    name: app-operator
 spec:
   replicas: 1
   selector:
@@ -37,6 +39,9 @@ spec:
       containers:
         - name: app-operator
           image: quay.io/example-inc/app-operator:0.0.1
+          ports:
+          - containerPort: 9090
+            name: metrics
           command:
           - app-operator
           imagePullPolicy: Always
@@ -95,6 +100,34 @@ roleRef:
   apiGroup: rbac.authorization.k8s.io
 `
 
+const serviceYamlExp = `apiVersion: v1
+kind: Service
+metadata:
+  name: app-operator
+  labels:
+    name: app-operator
+spec:
+  selector:
+    name: app-operator
+  ports:
+  - protocol: TCP
+    targetPort: metrics
+    port: 9090
+    name: metrics`
+
+const serviceMonitorYamlExp = `apiVersion: monitoring.coreos.com/v1
+kind: ServiceMonitor
+metadata:
+  name: app-operator
+  labels:
+    name: app-operator
+spec:
+  selector:
+    matchLabels:
+      name: app-operator
+  endpoints:
+  - port: metrics`
+
 func TestGenDeploy(t *testing.T) {
 	buf := &bytes.Buffer{}
 	if err := renderCRDYaml(buf, appKind, appAPIVersion); err != nil {
@@ -119,4 +152,20 @@ func TestGenDeploy(t *testing.T) {
 	if rbacYamlExp != buf.String() {
 		t.Errorf("want %v, got %v", rbacYamlExp, buf.String())
 	}
+
+	buf = &bytes.Buffer{}
+	if err := renderServiceYaml(buf, appProjectName); err != nil {
+		t.Error(err)
+	}
+	if serviceYamlExp != buf.String() {
+		t.Errorf("want %v, got %v", serviceYamlExp, buf.String())
+	}
+
+	buf = &bytes.Buffer{}
+	if err := renderServiceMonitorYaml(buf, appProjectName); err != nil {
+		t.Error(err)
+	}
+	if serviceMonitorYamlExp != buf.String() {
+		t.Errorf("want %v, got %v", serviceMonitorYamlExp, buf.String())
+	}
 }

pkg/generator/gen_deploy_test.go

@@ -54,6 +54,8 @@ const (
 	gopkglock          = "Gopkg.lock"
 	config             = "config.yaml"
 	operatorYaml       = deployDir + "/operator.yaml"
+	serviceYaml        = "service.yaml"
+	serviceMonitorYaml = "serviceMonitor.yaml"
 	rbacYaml           = "rbac.yaml"
 	crYaml             = "cr.yaml"
 	catalogPackageYaml = "package.yaml"
@@ -206,6 +208,22 @@ func renderDeployFiles(deployDir, projectName, apiVersion, kind string) error {
 		return err
 	}
 
+	buf = &bytes.Buffer{}
+	if err := renderServiceYaml(buf, projectName); err != nil {
+		return err
+	}
+	if err := writeFileAndPrint(filepath.Join(deployDir, serviceYaml), buf.Bytes(), defaultFileMode); err != nil {
+		return err
+	}
+
+	buf = &bytes.Buffer{}
+	if err := renderServiceMonitorYaml(buf, projectName); err != nil {
+		return err
+	}
+	if err := writeFileAndPrint(filepath.Join(deployDir, serviceMonitorYaml), buf.Bytes(), defaultFileMode); err != nil {
+		return err
+	}
+
 	buf = &bytes.Buffer{}
 	if err := renderCRDYaml(buf, kind, apiVersion); err != nil {
 		return err
@@ -230,6 +248,24 @@ func RenderOperatorYaml(c *Config, image string) error {
 	return ioutil.WriteFile(operatorYaml, buf.Bytes(), defaultFileMode)
 }
 
+// RenderServiceYaml generates "deploy/service.yaml"
+func RenderServiceYaml(c *Config) error {
+	buf := &bytes.Buffer{}
+	if err := renderServiceYaml(buf, c.ProjectName); err != nil {
+		return err
+	}
+	return ioutil.WriteFile(serviceYaml, buf.Bytes(), defaultFileMode)
+}
+
+// RenderServiceMonitorYaml generates "deploy/serviceMonitor.yaml"
+func RenderServiceMonitorYaml(c *Config) error {
+	buf := &bytes.Buffer{}
+	if err := renderServiceMonitorYaml(buf, c.ProjectName); err != nil {
+		return err
+	}
+	return ioutil.WriteFile(serviceMonitorYaml, buf.Bytes(), defaultFileMode)
+}
+
 // RenderOlmCatalog generates catalog manifests "deploy/olm-catalog/*"
 // The current working directory must be the project repository root
 func RenderOlmCatalog(c *Config, image, version string) error {

pkg/generator/generator.go

@@ -20,24 +20,33 @@ const mainTmpl = `package main
 import (
 	"context"
 	"runtime"
+	"net/http"
 
 	stub "{{.StubImport}}"
 	sdk "{{.OperatorSDKImport}}"
 	k8sutil "{{.K8sutilImport}}"
 	sdkVersion "{{.SDKVersionImport}}"
 
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/sirupsen/logrus"
 )
 
+// Prometheus metrics port
+const promPort = ":9090"
+
 func printVersion() {
 	logrus.Infof("Go Version: %s", runtime.Version())
 	logrus.Infof("Go OS/Arch: %s/%s", runtime.GOOS, runtime.GOARCH)
 	logrus.Infof("operator-sdk Version: %v", sdkVersion.Version)
+	logrus.Infof("operator prometheus port :%s", promPort)
 }
 
 func main() {
 	printVersion()
 
+	http.Handle("/metrics", promhttp.Handler())
+	logrus.Fatalf("%s", http.ListenAndServe(promPort, nil))
+
 	resource := "{{.APIVersion}}"
 	kind := "{{.Kind}}"
 	namespace, err := k8sutil.GetWatchNamespace()