Propagate headers to lifecycle handlers

Propagate HTTP headers to HTTP-based lifecycle handlers. This normalizes
the underlying HTTPGetAction of lifecycle handlers with that of probes,
which do already propagate HTTP headers.

pkg/kubelet/kuberuntime/fake_kuberuntime_manager.go

@@ -40,12 +40,12 @@ const (
 )
 
 type fakeHTTP struct {
-	url string
+	req *http.Request
 	err error
 }
 
-func (f *fakeHTTP) Get(url string) (*http.Response, error) {
-	f.url = url
+func (f *fakeHTTP) Do(req *http.Request) (*http.Response, error) {
+	f.req = req
 	return nil, f.err
 }
 

pkg/kubelet/kuberuntime/kuberuntime_container_test.go

@@ -17,6 +17,7 @@ limitations under the License.
 package kuberuntime
 
 import (
+	"net/http"
 	"path/filepath"
 	"strings"
 	"testing"
@@ -279,11 +280,11 @@ func TestLifeCycleHook(t *testing.T) {
 
 	// Configured and working HTTP hook
 	t.Run("PreStop-HTTPGet", func(t *testing.T) {
-		defer func() { fakeHTTP.url = "" }()
+		defer func() { fakeHTTP.req, _ = http.NewRequest(http.MethodGet, "", nil) }()
 		testPod.Spec.Containers[0].Lifecycle = httpLifeCycle
 		m.killContainer(testPod, cID, "foo", "testKill", &gracePeriod)
 
-		if !strings.Contains(fakeHTTP.url, httpLifeCycle.PreStop.HTTPGet.Host) {
+		if !strings.Contains(fakeHTTP.req.URL.String(), httpLifeCycle.PreStop.HTTPGet.Host) {
 			t.Errorf("HTTP Prestop hook was not invoked")
 		}
 	})
@@ -297,7 +298,7 @@ func TestLifeCycleHook(t *testing.T) {
 
 		m.killContainer(testPod, cID, "foo", "testKill", &gracePeriodLocal)
 
-		if strings.Contains(fakeHTTP.url, httpLifeCycle.PreStop.HTTPGet.Host) {
+		if strings.Contains(fakeHTTP.req.URL.String(), httpLifeCycle.PreStop.HTTPGet.Host) {
 			t.Errorf("HTTP Should not execute when gracePeriod is 0")
 		}
 	})

pkg/kubelet/kuberuntime/kuberuntime_manager.go

@@ -159,7 +159,7 @@ func NewKubeGenericRuntimeManager(
 	podStateProvider podStateProvider,
 	osInterface kubecontainer.OSInterface,
 	runtimeHelper kubecontainer.RuntimeHelper,
-	httpClient types.HTTPGetter,
+	httpClient types.HttpDoer,
 	imageBackOff *flowcontrol.Backoff,
 	serializeImagePulls bool,
 	imagePullQPS float32,

pkg/kubelet/lifecycle/handlers.go

@@ -39,7 +39,7 @@ const (
 )
 
 type HandlerRunner struct {
-	httpGetter       kubetypes.HTTPGetter
+	httpDoer         kubetypes.HttpDoer
 	commandRunner    kubecontainer.ContainerCommandRunner
 	containerManager podStatusProvider
 }
@@ -48,9 +48,9 @@ type podStatusProvider interface {
 	GetPodStatus(uid types.UID, name, namespace string) (*kubecontainer.PodStatus, error)
 }
 
-func NewHandlerRunner(httpGetter kubetypes.HTTPGetter, commandRunner kubecontainer.ContainerCommandRunner, containerManager podStatusProvider) kubecontainer.HandlerRunner {
+func NewHandlerRunner(httpDoer kubetypes.HttpDoer, commandRunner kubecontainer.ContainerCommandRunner, containerManager podStatusProvider) kubecontainer.HandlerRunner {
 	return &HandlerRunner{
-		httpGetter:       httpGetter,
+		httpDoer:         httpDoer,
 		commandRunner:    commandRunner,
 		containerManager: containerManager,
 	}
@@ -108,7 +108,7 @@ func resolvePort(portReference intstr.IntOrString, container *v1.Container) (int
 // formatURL formats a URL from args.
 func formatURL(scheme string, host string, port int, path string) *url.URL {
 	u, err := url.Parse(path)
-	// Something is bustsed with the path, but it's too late to reject it. Pass it along as is.
+	// Something is busted with the path, but it's too late to reject it. Pass it along as is.
 	if err != nil {
 		u = &url.URL{
 			Path: path,
@@ -119,6 +119,16 @@ func formatURL(scheme string, host string, port int, path string) *url.URL {
 	return u
 }
 
+// buildHeader takes a list of HTTPHeader <name, value> string pairs
+// and returns a populated string->[]string http.Header map.
+func buildHeader(headerList []v1.HTTPHeader) http.Header {
+	headers := make(http.Header)
+	for _, header := range headerList {
+		headers[header.Name] = append(headers[header.Name], header.Value)
+	}
+	return headers
+}
+
 func (hr *HandlerRunner) runHTTPHandler(pod *v1.Pod, container *v1.Container, handler *v1.Handler) (string, error) {
 	host := handler.HTTPGet.Host
 	if len(host) == 0 {
@@ -144,7 +154,14 @@ func (hr *HandlerRunner) runHTTPHandler(pod *v1.Pod, container *v1.Container, ha
 	}
 	path := handler.HTTPGet.Path
 	url := formatURL("http", host, port, path)
-	resp, err := hr.httpGetter.Get(url.String())
+
+	req, err := http.NewRequest(http.MethodGet, url.String(), nil)
+	if err != nil {
+		return "", err
+	}
+	req.Header = buildHeader(handler.HTTPGet.HTTPHeaders)
+	resp, err := hr.httpDoer.Do(req)
+
 	return getHttpRespBody(resp), err
 }
 

pkg/kubelet/lifecycle/handlers_test.go

@@ -122,13 +122,15 @@ func TestRunHandlerExec(t *testing.T) {
 }
 
 type fakeHTTP struct {
-	url  string
-	err  error
-	resp *http.Response
+	url     string
+	headers http.Header
+	err     error
+	resp    *http.Response
 }
 
-func (f *fakeHTTP) Get(url string) (*http.Response, error) {
-	f.url = url
+func (f *fakeHTTP) Do(req *http.Request) (*http.Response, error) {
+	f.url = req.URL.String()
+	f.headers = req.Header.Clone()
 	return f.resp, f.err
 }
 
@@ -165,6 +167,45 @@ func TestRunHandlerHttp(t *testing.T) {
 	}
 }
 
+func TestRunHandlerHttpWithHeaders(t *testing.T) {
+	fakeHttp := fakeHTTP{}
+	handlerRunner := NewHandlerRunner(&fakeHttp, &fakeContainerCommandRunner{}, nil)
+
+	containerID := kubecontainer.ContainerID{Type: "test", ID: "abc1234"}
+	containerName := "containerFoo"
+
+	container := v1.Container{
+		Name: containerName,
+		Lifecycle: &v1.Lifecycle{
+			PostStart: &v1.Handler{
+				HTTPGet: &v1.HTTPGetAction{
+					Host: "foo",
+					Port: intstr.FromInt(8080),
+					Path: "/bar",
+					HTTPHeaders: []v1.HTTPHeader{
+						{Name: "foo", Value: "bar"},
+					},
+				},
+			},
+		},
+	}
+	pod := v1.Pod{}
+	pod.ObjectMeta.Name = "podFoo"
+	pod.ObjectMeta.Namespace = "nsFoo"
+	pod.Spec.Containers = []v1.Container{container}
+	_, err := handlerRunner.Run(containerID, &pod, &container, container.Lifecycle.PostStart)
+
+	if err != nil {
+		t.Errorf("unexpected error: %v", err)
+	}
+	if fakeHttp.url != "http://foo:8080/bar" {
+		t.Errorf("unexpected url: %s", fakeHttp.url)
+	}
+	if fakeHttp.headers["foo"][0] != "bar" {
+		t.Errorf("missing http header: %s", fakeHttp.headers)
+	}
+}
+
 func TestRunHandlerNil(t *testing.T) {
 	handlerRunner := NewHandlerRunner(&fakeHTTP{}, &fakeContainerCommandRunner{}, nil)
 	containerID := kubecontainer.ContainerID{Type: "test", ID: "abc1234"}

pkg/kubelet/types/types.go

@@ -26,10 +26,9 @@ import (
 
 // TODO: Reconcile custom types in kubelet/types and this subpackage
 
-// HTTPGetter is an interface representing the ability to perform HTTP GET requests.
-type HTTPGetter interface {
-	// Get issues a GET to the specified URL.
-	Get(url string) (*http.Response, error)
+// HttpDoer encapsulates http.Do functionality
+type HttpDoer interface {
+	Do(req *http.Request) (*http.Response, error)
 }
 
 // Timestamp wraps around time.Time and offers utilities to format and parse