Merge pull request agones-dev#34 from googleprivate/health

Add health check.

Author: markmandel

build/install.yaml

@@ -51,3 +51,9 @@ spec:
           value: "true"
         - name: SIDECAR # overwrite the GameServer sidecar image that is used
           value: ${REGISTRY}/gameservers-sidecar:${VERSION}
+        livenessProbe:
+          httpGet:
+            path: /healthz
+            port: 8080
+          initialDelaySeconds: 3
+          periodSeconds: 3

gameservers/controller/controller.go

@@ -17,6 +17,8 @@ package main
 import (
 	"time"
 
+	"net/http"
+
 	"github.com/agonio/agon/pkg/apis/stable"
 	stablev1alpha1 "github.com/agonio/agon/pkg/apis/stable/v1alpha1"
 	"github.com/agonio/agon/pkg/client/clientset/versioned"
@@ -58,6 +60,7 @@ type Controller struct {
 	gameServerSynced       cache.InformerSynced
 	nodeLister             corelisterv1.NodeLister
 	queue                  workqueue.RateLimitingInterface
+	server                 *http.Server
 
 	// this allows for overwriting for testing purposes
 	syncHandler func(string) error
@@ -102,6 +105,16 @@ func NewController(sidecarImage string,
 
 	c.syncHandler = c.syncGameServer
 
+	mux := http.NewServeMux()
+	mux.HandleFunc("/healthz", func(w http.ResponseWriter, r *http.Request) {
+		w.Write([]byte("ok"))
+	})
+
+	c.server = &http.Server{
+		Addr:    ":8080",
+		Handler: mux,
+	}
+
 	return c
 }
 
@@ -110,6 +123,14 @@ func NewController(sidecarImage string,
 func (c Controller) Run(threadiness int, stop <-chan struct{}) error {
 	defer c.queue.ShutDown()
 
+	logrus.Info("Starting health check...")
+	go func() {
+		if err := c.server.ListenAndServe(); err != nil {
+			logrus.WithError(err).Error("Could not listen on :8080")
+		}
+	}()
+	defer c.server.Close()
+
 	err := c.waitForEstablishedCRD()
 	if err != nil {
 		return err

gameservers/controller/controller_test.go

@@ -21,6 +21,9 @@ import (
 
 	"fmt"
 
+	"io/ioutil"
+	"net/http"
+
 	"github.com/agonio/agon/pkg/apis/stable"
 	"github.com/agonio/agon/pkg/apis/stable/v1alpha1"
 	agonfake "github.com/agonio/agon/pkg/client/clientset/versioned/fake"
@@ -158,8 +161,6 @@ func TestSyncGameServer(t *testing.T) {
 }
 
 func TestWatchGameServers(t *testing.T) {
-	t.Parallel()
-
 	c, mocks := newFakeController()
 	fixture := v1alpha1.GameServer{ObjectMeta: metav1.ObjectMeta{Name: "test", Namespace: "default"}}
 	fakeWatch := watch.NewFake()
@@ -198,6 +199,32 @@ func TestWatchGameServers(t *testing.T) {
 	assert.Equal(t, "default/test", <-received)
 }
 
+func TestHealthCheck(t *testing.T) {
+	c, mocks := newFakeController()
+	mocks.extClient.AddReactor("get", "customresourcedefinitions", func(action k8stesting.Action) (bool, runtime.Object, error) {
+		return true, newEstablishedCRD(), nil
+	})
+
+	c.syncHandler = func(name string) error {
+		return nil
+	}
+
+	stop := startInformers(c, mocks)
+	defer close(stop)
+
+	go func() {
+		err := c.Run(1, stop)
+		assert.Nil(t, err, "Run should not error")
+	}()
+
+	resp, err := http.Get("http://localhost:8080/healthz")
+	assert.Nil(t, err, "health check error should be nil")
+	defer resp.Body.Close()
+	body, err := ioutil.ReadAll(resp.Body)
+	assert.Nil(t, err, "read response error should be nil")
+	assert.Equal(t, []byte("ok"), body, "response body should be 'ok'")
+}
+
 func TestSyncGameServerBlankState(t *testing.T) {
 
 	t.Run("GameServer with a blank initial state", func(t *testing.T) {

install.yaml

@@ -41,8 +41,14 @@ spec:
         stable.agon.io/role: controller
     spec:
       containers:
-      - nameW: gameservers-controller
+      - name: gameservers-controller
         image: gcr.io/agon-images/gameservers-controller:0.1
         env:
         # - name: SIDECAR # overwrite the GameServer sidecar image that is used
         #   value: gcr.io/agon-images/gameservers-sidecar:0.1
+        livenessProbe:
+          httpGet:
+            path: /healthz
+            port: 8080
+          initialDelaySeconds: 3
+          periodSeconds: 3