Implement HealthzChecker interface. Add flag to allow profiling

Godeps/Godeps.json

@@ -618,6 +618,11 @@
 			"Comment": "v1.2.1-beta.0",
 			"Rev": "fd557a2c9f47c655f9c07d9cf9dee2539e935703"
 		},
+		{
+			"ImportPath": "k8s.io/kubernetes/pkg/healthz",
+			"Comment": "v1.2.1-beta.0",
+			"Rev": "fd557a2c9f47c655f9c07d9cf9dee2539e935703"
+		},
 		{
 			"ImportPath": "k8s.io/kubernetes/pkg/kubectl",
 			"Comment": "v1.2.1-beta.0",

Godeps/_workspace/src/k8s.io/kubernetes/pkg/healthz/doc.go

@@ -0,0 +1,20 @@
+/*
+Copyright 2014 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package healthz implements basic http server health checking.
+// Usage:
+//   import _ "healthz" registers a handler on the path '/healthz', that serves 200s
+package healthz

Godeps/_workspace/src/k8s.io/kubernetes/pkg/healthz/healthz.go

@@ -0,0 +1,133 @@
+/*
+Copyright 2014 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package healthz
+
+import (
+	"bytes"
+	"fmt"
+	"net/http"
+	"sync"
+)
+
+// HealthzChecker is a named healthz check.
+type HealthzChecker interface {
+	Name() string
+	Check(req *http.Request) error
+}
+
+var defaultHealthz = sync.Once{}
+
+// DefaultHealthz installs the default healthz check to the http.DefaultServeMux.
+func DefaultHealthz(checks ...HealthzChecker) {
+	defaultHealthz.Do(func() {
+		InstallHandler(http.DefaultServeMux, checks...)
+	})
+}
+
+// PingHealthz returns true automatically when checked
+var PingHealthz HealthzChecker = ping{}
+
+// ping implements the simplest possible health checker.
+type ping struct{}
+
+func (ping) Name() string {
+	return "ping"
+}
+
+// PingHealthz is a health check that returns true.
+func (ping) Check(_ *http.Request) error {
+	return nil
+}
+
+// NamedCheck returns a health checker for the given name and function.
+func NamedCheck(name string, check func(r *http.Request) error) HealthzChecker {
+	return &healthzCheck{name, check}
+}
+
+// InstallHandler registers a handler for health checking on the path "/healthz" to mux.
+func InstallHandler(mux mux, checks ...HealthzChecker) {
+	if len(checks) == 0 {
+		checks = []HealthzChecker{PingHealthz}
+	}
+	mux.Handle("/healthz", handleRootHealthz(checks...))
+	for _, check := range checks {
+		mux.Handle(fmt.Sprintf("/healthz/%v", check.Name()), adaptCheckToHandler(check.Check))
+	}
+}
+
+// mux is an interface describing the methods InstallHandler requires.
+type mux interface {
+	Handle(pattern string, handler http.Handler)
+}
+
+// healthzCheck implements HealthzChecker on an arbitrary name and check function.
+type healthzCheck struct {
+	name  string
+	check func(r *http.Request) error
+}
+
+var _ HealthzChecker = &healthzCheck{}
+
+func (c *healthzCheck) Name() string {
+	return c.name
+}
+
+func (c *healthzCheck) Check(r *http.Request) error {
+	return c.check(r)
+}
+
+// handleRootHealthz returns an http.HandlerFunc that serves the provided checks.
+func handleRootHealthz(checks ...HealthzChecker) http.HandlerFunc {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		failed := false
+		var verboseOut bytes.Buffer
+		for _, check := range checks {
+			err := check.Check(r)
+			if err != nil {
+				fmt.Fprintf(&verboseOut, "[-]%v failed: %v\n", check.Name(), err)
+				failed = true
+			} else {
+				fmt.Fprintf(&verboseOut, "[+]%v ok\n", check.Name())
+			}
+		}
+		// always be verbose on failure
+		if failed {
+			http.Error(w, fmt.Sprintf("%vhealthz check failed", verboseOut.String()), http.StatusInternalServerError)
+			return
+		}
+
+		if _, found := r.URL.Query()["verbose"]; !found {
+			fmt.Fprint(w, "ok")
+			return
+		}
+
+		verboseOut.WriteTo(w)
+		fmt.Fprint(w, "healthz check passed\n")
+	})
+}
+
+// adaptCheckToHandler returns an http.HandlerFunc that serves the provided checks.
+func adaptCheckToHandler(c func(r *http.Request) error) http.HandlerFunc {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		err := c(r)
+		if err != nil {
+			http.Error(w, fmt.Sprintf("Internal server error: %v", err), http.StatusInternalServerError)
+		} else {
+			fmt.Fprint(w, "ok")
+		}
+	})
+}

controllers/nginx-third-party/controller.go

@@ -18,7 +18,6 @@ package main
 
 import (
 	"fmt"
-	"net/http"
 	"sort"
 	"strconv"
 	"strings"
@@ -54,7 +53,7 @@ type loadBalancerController struct {
 	ingLister      StoreToIngressLister
 	svcLister      cache.StoreToServiceLister
 	endpLister     cache.StoreToEndpointsLister
-	nginx          *nginx.NginxManager
+	nginx          *nginx.Manager
 	lbInfo         *lbInfo
 	defaultSvc     string
 	nxgConfigMap   string
@@ -149,25 +148,6 @@ func (lbc *loadBalancerController) getTCPConfigMap(ns, name string) (*api.Config
 	return lbc.client.ConfigMaps(ns).Get(name)
 }
 
-func (lbc *loadBalancerController) registerHandlers() {
-	http.HandleFunc("/healthz", func(w http.ResponseWriter, r *http.Request) {
-		if err := lbc.nginx.IsHealthy(); err != nil {
-			w.WriteHeader(500)
-			w.Write([]byte("nginx error"))
-			return
-		}
-
-		w.WriteHeader(200)
-		w.Write([]byte("ok"))
-	})
-
-	http.HandleFunc("/stop", func(w http.ResponseWriter, r *http.Request) {
-		lbc.Stop()
-	})
-
-	glog.Fatalf(fmt.Sprintf("%v", http.ListenAndServe(fmt.Sprintf(":%v", *healthzPort), nil)))
-}
-
 func (lbc *loadBalancerController) sync() {
 	ings := lbc.ingLister.Store.List()
 	upstreams, servers := lbc.getUpstreamServers(ings)
@@ -540,7 +520,6 @@ func (lbc *loadBalancerController) Stop() {
 func (lbc *loadBalancerController) Run() {
 	glog.Infof("starting NGINX loadbalancer controller")
 	go lbc.nginx.Start()
-	go lbc.registerHandlers()
 
 	go lbc.ingController.Run(lbc.stopCh)
 	go lbc.endpController.Run(lbc.stopCh)

controllers/nginx-third-party/main.go

@@ -19,6 +19,8 @@ package main
 import (
 	"flag"
 	"fmt"
+	"net/http"
+	"net/http/pprof"
 	"os"
 	"time"
 
@@ -29,6 +31,7 @@ import (
 
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/client/unversioned"
+	"k8s.io/kubernetes/pkg/healthz"
 	"k8s.io/kubernetes/pkg/runtime"
 )
 
@@ -64,6 +67,8 @@ var (
 
 	buildCfg = flags.Bool("dump-nginx—configuration", false, `Returns a ConfigMap with the default nginx conguration.
 		This can be used as a guide to create a custom configuration.`)
+
+	profiling = flags.Bool("profiling", true, `Enable profiling via web interface host:port/debug/pprof/`)
 )
 
 func main() {
@@ -99,6 +104,8 @@ func main() {
 		glog.Fatalf("%v", err)
 	}
 
+	go registerHandlers(lbc)
+
 	lbc.Run()
 
 	for {
@@ -115,3 +122,24 @@ type lbInfo struct {
 	PodIP        string
 	PodNamespace string
 }
+
+func registerHandlers(lbc *loadBalancerController) {
+	mux := http.NewServeMux()
+	healthz.InstallHandler(mux, lbc.nginx)
+
+	http.HandleFunc("/stop", func(w http.ResponseWriter, r *http.Request) {
+		lbc.Stop()
+	})
+
+	if *profiling {
+		mux.HandleFunc("/debug/pprof/", pprof.Index)
+		mux.HandleFunc("/debug/pprof/profile", pprof.Profile)
+		mux.HandleFunc("/debug/pprof/symbol", pprof.Symbol)
+	}
+
+	server := &http.Server{
+		Addr:    fmt.Sprintf(":%v", *healthzPort),
+		Handler: mux,
+	}
+	glog.Fatal(server.ListenAndServe())
+}

controllers/nginx-third-party/nginx/command.go

@@ -17,15 +17,19 @@ limitations under the License.
 package nginx
 
 import (
+	"fmt"
+	"net/http"
 	"os"
 	"os/exec"
 
 	"github.com/golang/glog"
+
+	"k8s.io/kubernetes/pkg/healthz"
 )
 
 // Start starts a nginx (master process) and waits. If the process ends
 // we need to kill the controller process and return the reason.
-func (ngx *NginxManager) Start() {
+func (ngx *Manager) Start() {
 	glog.Info("Starting NGINX process...")
 	cmd := exec.Command("nginx")
 	cmd.Stdout = os.Stdout
@@ -50,7 +54,7 @@ func (ngx *NginxManager) Start() {
 // shut down, stop accepting new connections and continue to service current requests
 // until all such requests are serviced. After that, the old worker processes exit.
 // http://nginx.org/en/docs/beginners_guide.html#control
-func (ngx *NginxManager) CheckAndReload(cfg *nginxConfiguration, ingressCfg IngressConfig) {
+func (ngx *Manager) CheckAndReload(cfg *nginxConfiguration, ingressCfg IngressConfig) {
 	ngx.reloadLock.Lock()
 	defer ngx.reloadLock.Unlock()
 
@@ -70,7 +74,7 @@ func (ngx *NginxManager) CheckAndReload(cfg *nginxConfiguration, ingressCfg Ingr
 
 // shellOut executes a command and returns its combined standard output and standard
 // error in case of an error in the execution
-func (ngx *NginxManager) shellOut(cmd string) error {
+func (ngx *Manager) shellOut(cmd string) error {
 	out, err := exec.Command("sh", "-c", cmd).CombinedOutput()
 	if err != nil {
 		glog.Errorf("failed to execute %v: %v", cmd, string(out))
@@ -79,3 +83,26 @@ func (ngx *NginxManager) shellOut(cmd string) error {
 
 	return nil
 }
+
+// check to verify Manager implements HealthzChecker interface
+var _ healthz.HealthzChecker = Manager{}
+
+// Name returns the healthcheck name
+func (ngx Manager) Name() string {
+	return "NGINX"
+}
+
+// Check returns if the nginx healthz endpoint is returning ok (status code 200)
+func (ngx Manager) Check(_ *http.Request) error {
+	res, err := http.Get("http://127.0.0.1:8080/healthz")
+	if err != nil {
+		return err
+	}
+	defer res.Body.Close()
+
+	if res.StatusCode != 200 {
+		return fmt.Errorf("NGINX is unhealthy")
+	}
+
+	return nil
+}

controllers/nginx-third-party/nginx/main.go

@@ -203,8 +203,8 @@ type nginxConfiguration struct {
 	WorkerProcesses string `json:"workerProcesses,omitempty" structs:"workerProcesses,omitempty"`
 }
 
-// NginxManager ...
-type NginxManager struct {
+// Manager ...
+type Manager struct {
 	ConfigFile string
 
 	defCfg *nginxConfiguration
@@ -257,11 +257,11 @@ func newDefaultNginxCfg() *nginxConfiguration {
 }
 
 // NewManager ...
-func NewManager(kubeClient *client.Client) *NginxManager {
-	ngx := &NginxManager{
+func NewManager(kubeClient *client.Client) *Manager {
+	ngx := &Manager{
 		ConfigFile:  "/etc/nginx/nginx.conf",
 		defCfg:      newDefaultNginxCfg(),
-		defResolver: strings.Join(getDnsServers(), " "),
+		defResolver: strings.Join(getDNSServers(), " "),
 		reloadLock:  &sync.Mutex{},
 	}
 
@@ -274,7 +274,7 @@ func NewManager(kubeClient *client.Client) *NginxManager {
 	return ngx
 }
 
-func (nginx *NginxManager) createCertsDir(base string) {
+func (nginx *Manager) createCertsDir(base string) {
 	if err := os.Mkdir(base, os.ModeDir); err != nil {
 		glog.Fatalf("Couldn't create directory %v: %v", base, err)
 	}

controllers/nginx-third-party/nginx/ssl.go

@@ -27,7 +27,7 @@ import (
 )
 
 // AddOrUpdateCertAndKey creates a .pem file wth the cert and the key with the specified name
-func (nginx *NginxManager) AddOrUpdateCertAndKey(name string, cert string, key string) string {
+func (nginx *Manager) AddOrUpdateCertAndKey(name string, cert string, key string) string {
 	pemFileName := sslDirectory + "/" + name + ".pem"
 
 	pem, err := os.Create(pemFileName)
@@ -47,7 +47,7 @@ func (nginx *NginxManager) AddOrUpdateCertAndKey(name string, cert string, key s
 // CheckSSLCertificate checks if the certificate and key file are valid
 // returning the result of the validation and the list of hostnames
 // contained in the common name/s
-func (nginx *NginxManager) CheckSSLCertificate(secretName string) ([]string, error) {
+func (nginx *Manager) CheckSSLCertificate(secretName string) ([]string, error) {
 	pemFileName := sslDirectory + "/" + secretName + ".pem"
 	pemCerts, err := ioutil.ReadFile(pemFileName)
 	if err != nil {
@@ -55,7 +55,7 @@ func (nginx *NginxManager) CheckSSLCertificate(secretName string) ([]string, err
 	}
 
 	var block *pem.Block
-	block, pemCerts = pem.Decode(pemCerts)
+	block, _ = pem.Decode(pemCerts)
 
 	cert, err := x509.ParseCertificate(block.Bytes)
 	if err != nil {
@@ -74,7 +74,7 @@ func (nginx *NginxManager) CheckSSLCertificate(secretName string) ([]string, err
 // SearchDHParamFile iterates all the secrets mounted inside the /etc/nginx-ssl directory
 // in order to find a file with the name dhparam.pem. If such file exists it will
 // returns the path. If not it just returns an empty string
-func (nginx *NginxManager) SearchDHParamFile(baseDir string) string {
+func (nginx *Manager) SearchDHParamFile(baseDir string) string {
 	files, _ := ioutil.ReadDir(baseDir)
 	for _, file := range files {
 		if !file.IsDir() {

controllers/nginx-third-party/nginx/template.go

@@ -37,12 +37,12 @@ var funcMap = template.FuncMap{
 	},
 }
 
-func (ngx *NginxManager) loadTemplate() {
+func (ngx *Manager) loadTemplate() {
 	tmpl, _ := template.New("nginx.tmpl").Funcs(funcMap).ParseFiles("./nginx.tmpl")
 	ngx.template = tmpl
 }
 
-func (ngx *NginxManager) writeCfg(cfg *nginxConfiguration, ingressCfg IngressConfig) (bool, error) {
+func (ngx *Manager) writeCfg(cfg *nginxConfiguration, ingressCfg IngressConfig) (bool, error) {
 	fromMap := structs.Map(cfg)
 	toMap := structs.Map(ngx.defCfg)
 	curNginxCfg := merge(toMap, fromMap)

controllers/nginx-third-party/nginx/utils.go

@@ -19,9 +19,7 @@ package nginx
 import (
 	"bytes"
 	"encoding/json"
-	"fmt"
 	"io/ioutil"
-	"net/http"
 	"os"
 	"os/exec"
 	"reflect"
@@ -33,23 +31,8 @@ import (
 	"k8s.io/kubernetes/pkg/api"
 )
 
-// IsHealthy checks if nginx is running
-func (ngx *NginxManager) IsHealthy() error {
-	res, err := http.Get("http://127.0.0.1:8080/healthz")
-	if err != nil {
-		return err
-	}
-	defer res.Body.Close()
-
-	if res.StatusCode != 200 {
-		return fmt.Errorf("NGINX is unhealthy")
-	}
-
-	return nil
-}
-
-// getDnsServers returns the list of nameservers located in the file /etc/resolv.conf
-func getDnsServers() []string {
+// getDNSServers returns the list of nameservers located in the file /etc/resolv.conf
+func getDNSServers() []string {
 	file, err := ioutil.ReadFile("/etc/resolv.conf")
 	if err != nil {
 		return []string{}
@@ -78,7 +61,7 @@ func getDnsServers() []string {
 }
 
 // ReadConfig obtains the configuration defined by the user merged with the defaults.
-func (ngx *NginxManager) ReadConfig(config *api.ConfigMap) (*nginxConfiguration, error) {
+func (ngx *Manager) ReadConfig(config *api.ConfigMap) (*nginxConfiguration, error) {
 	if len(config.Data) == 0 {
 		return newDefaultNginxCfg(), nil
 	}
@@ -96,7 +79,7 @@ func (ngx *NginxManager) ReadConfig(config *api.ConfigMap) (*nginxConfiguration,
 	return cfg, nil
 }
 
-func (ngx *NginxManager) needsReload(data *bytes.Buffer) (bool, error) {
+func (ngx *Manager) needsReload(data *bytes.Buffer) (bool, error) {
 	filename := ngx.ConfigFile
 	in, err := os.Open(filename)
 	if err != nil {