Addressed comments.

pkg/health/doc.go

@@ -0,0 +1,18 @@
+/*
+Copyright 2014 Google Inc. 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 health contains utilities for health checking, as well as health status information.
+package health

pkg/health/health.go

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package util
+package health
 
 import (
 	"net/http"
@@ -22,30 +22,30 @@ import (
 	"github.com/golang/glog"
 )
 
-type HealthCheckStatus int
+type Status int
 
 const (
-	CheckHealthy   HealthCheckStatus = 0
+	Healthy Status = iota
-	CheckUnhealthy HealthCheckStatus = 1
+	Unhealthy
-	CheckUnknown   HealthCheckStatus = 2
+	Unknown
 )
 
 type HTTPGetInterface interface {
 	Get(url string) (*http.Response, error)
 }
 
-func IsHealthy(url string, client HTTPGetInterface) (HealthCheckStatus, error) {
+func Check(url string, client HTTPGetInterface) (Status, error) {
 	res, err := client.Get(url)
 	if res.Body != nil {
 		defer res.Body.Close()
 	}
 	if err != nil {
-		return CheckUnknown, err
+		return Unknown, err
 	}
 	if res.StatusCode >= http.StatusOK && res.StatusCode < http.StatusBadRequest {
-		return CheckHealthy, nil
+		return Healthy, nil
 	} else {
 		glog.V(1).Infof("Health check failed for %s, Response: %v", url, *res)
-		return CheckUnhealthy, nil
+		return Unhealthy, nil
 	}
 }

pkg/health/health_check.go

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package kubelet
+package health
 
 import (
 	"fmt"
@@ -22,12 +22,11 @@ import (
 	"strconv"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
-	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
 	"github.com/golang/glog"
 )
 
 type HealthChecker interface {
-	HealthCheck(container api.Container) (util.HealthCheckStatus, error)
+	HealthCheck(container api.Container) (Status, error)
 }
 
 // MakeHealthChecker creates a new HealthChecker.
@@ -46,18 +45,18 @@ type MuxHealthChecker struct {
 	checkers map[string]HealthChecker
 }
 
-func (m *MuxHealthChecker) HealthCheck(container api.Container) (util.HealthCheckStatus, error) {
+func (m *MuxHealthChecker) HealthCheck(container api.Container) (Status, error) {
 	checker, ok := m.checkers[container.LivenessProbe.Type]
 	if !ok || checker == nil {
 		glog.Warningf("Failed to find health checker for %s %s", container.Name, container.LivenessProbe.Type)
-		return util.CheckUnknown, nil
+		return Unknown, nil
 	}
 	return checker.HealthCheck(container)
 }
 
 // HTTPHealthChecker is an implementation of HealthChecker which checks container health by sending HTTP Get requests.
 type HTTPHealthChecker struct {
-	client util.HTTPGetInterface
+	client HTTPGetInterface
 }
 
 func (h *HTTPHealthChecker) findPort(container api.Container, portName string) int64 {
@@ -70,17 +69,17 @@ func (h *HTTPHealthChecker) findPort(container api.Container, portName string) i
 	return -1
 }
 
-func (h *HTTPHealthChecker) HealthCheck(container api.Container) (util.HealthCheckStatus, error) {
+func (h *HTTPHealthChecker) HealthCheck(container api.Container) (Status, error) {
 	params := container.LivenessProbe.HTTPGet
 	if params == nil {
-		return util.CheckUnknown, fmt.Errorf("Error, no HTTP parameters specified: %v", container)
+		return Unknown, fmt.Errorf("Error, no HTTP parameters specified: %v", container)
 	}
 	port := h.findPort(container, params.Port)
 	if port == -1 {
 		var err error
 		port, err = strconv.ParseInt(params.Port, 10, 0)
 		if err != nil {
-			return util.CheckUnknown, err
+			return Unknown, err
 		}
 	}
 	var host string
@@ -90,5 +89,5 @@ func (h *HTTPHealthChecker) HealthCheck(container api.Container) (util.HealthChe
 		host = "localhost"
 	}
 	url := fmt.Sprintf("http://%s:%d%s", host, port, params.Path)
-	return util.IsHealthy(url, h.client)
+	return Check(url, h.client)
 }

pkg/health/health_check_test.go

@@ -14,14 +14,13 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package kubelet
+package health
 
 import (
 	"net/http"
 	"testing"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
-	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
 )
 
 type fakeHTTPClient struct {
@@ -57,7 +56,7 @@ func TestHttpHealth(t *testing.T) {
 	}
 
 	ok, err := check.HealthCheck(container)
-	if ok != util.CheckHealthy {
+	if ok != Healthy {
 		t.Error("Unexpected unhealthy")
 	}
 	if err != nil {

pkg/kubelet/kubelet.go

@@ -34,6 +34,7 @@ import (
 	"time"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/health"
 	_ "github.com/GoogleCloudPlatform/kubernetes/pkg/healthz"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/tools"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
@@ -94,7 +95,7 @@ type Kubelet struct {
 	SyncFrequency      time.Duration
 	HTTPCheckFrequency time.Duration
 	pullLock           sync.Mutex
-	HealthChecker      HealthChecker
+	HealthChecker      health.HealthChecker
 }
 
 type manifestUpdate struct {
@@ -159,7 +160,7 @@ func (kl *Kubelet) RunKubelet(dockerEndpoint, configPath, manifestURL, etcdServe
 		}
 		go util.Forever(func() { s.ListenAndServe() }, 0)
 	}
-	kl.HealthChecker = MakeHealthChecker()
+	kl.HealthChecker = health.MakeHealthChecker()
 	kl.syncLoop(updateChannel, kl)
 }
 
@@ -736,7 +737,7 @@ func (kl *Kubelet) syncManifest(manifest *api.ContainerManifest, keepChannel cha
 				glog.V(1).Infof("health check errored: %v", err)
 				continue
 			}
-			if healthy != util.CheckHealthy {
+			if healthy != health.Healthy {
 				glog.V(1).Infof("manifest %s container %s is unhealthy.", manifest.ID, container.Name)
 				if err != nil {
 					glog.V(1).Infof("Failed to get container info %v, for %s", err, containerID)
@@ -993,16 +994,16 @@ func (kl *Kubelet) GetMachineStats() (*api.ContainerStats, error) {
 	return kl.statsFromContainerPath("/")
 }
 
-func (kl *Kubelet) healthy(container api.Container, dockerContainer *docker.APIContainers) (util.HealthCheckStatus, error) {
+func (kl *Kubelet) healthy(container api.Container, dockerContainer *docker.APIContainers) (health.Status, error) {
 	// Give the container 60 seconds to start up.
 	if container.LivenessProbe == nil {
-		return util.CheckHealthy, nil
+		return health.Healthy, nil
 	}
 	if time.Now().Unix()-dockerContainer.Created < container.LivenessProbe.InitialDelaySeconds {
-		return util.CheckHealthy, nil
+		return health.Healthy, nil
 	}
 	if kl.HealthChecker == nil {
-		return util.CheckHealthy, nil
+		return health.Healthy, nil
 	}
 	return kl.HealthChecker.HealthCheck(container)
 }

pkg/kubelet/kubelet_test.go

@@ -26,6 +26,7 @@ import (
 	"testing"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/health"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/tools"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
 	"github.com/coreos/go-etcd/etcd"
@@ -424,8 +425,8 @@ func TestSyncManifestsDeletes(t *testing.T) {
 
 type FalseHealthChecker struct{}
 
-func (f *FalseHealthChecker) HealthCheck(container api.Container) (util.HealthCheckStatus, error) {
+func (f *FalseHealthChecker) HealthCheck(container api.Container) (health.Status, error) {
-	return util.CheckUnhealthy, nil
+	return health.Unhealthy, nil
 }
 
 func TestSyncManifestsUnhealthy(t *testing.T) {

pkg/registry/healthy_minion_registry.go

@@ -20,12 +20,12 @@ import (
 	"fmt"
 	"net/http"
 
-	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/health"
 )
 
 type HealthyMinionRegistry struct {
 	delegate MinionRegistry
-	client   util.HTTPGetInterface
+	client   health.HTTPGetInterface
 	port     int
 }
 
@@ -48,11 +48,11 @@ func (h *HealthyMinionRegistry) List() (currentMinions []string, err error) {
 		return result, err
 	}
 	for _, minion := range list {
-		status, err := util.IsHealthy(h.makeMinionURL(minion), h.client)
+		status, err := health.Check(h.makeMinionURL(minion), h.client)
 		if err != nil {
 			return result, err
 		}
-		if status == util.CheckHealthy {
+		if status == health.Healthy {
 			result = append(result, minion)
 		}
 	}
@@ -75,11 +75,11 @@ func (h *HealthyMinionRegistry) Contains(minion string) (bool, error) {
 	if !contains {
 		return false, nil
 	}
-	status, err := util.IsHealthy(h.makeMinionURL(minion), h.client)
+	status, err := health.Check(h.makeMinionURL(minion), h.client)
 	if err != nil {
 		return false, err
 	}
-	if status == util.CheckUnhealthy {
+	if status == health.Unhealthy {
 		return false, nil
 	}
 	return true, nil