Golang util.NewBackOff函数代码示例

// This test assumes that the client implementation backs off exponentially, for an individual request.
func TestBackoffLifecycle(t *testing.T) {
	count := 0
	testServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
		count++
		t.Logf("Attempt %d", count)
		if count == 5 || count == 9 {
			w.WriteHeader(http.StatusOK)
			return
		} else {
			w.WriteHeader(http.StatusGatewayTimeout)
			return
		}
	}))
	// TODO: Uncomment when fix #19254
	// defer testServer.Close()
	c := testRESTClient(t, testServer)

	// Test backoff recovery and increase.  This correlates to the constants
	// which are used in the server implementation returning StatusOK above.
	seconds := []int{0, 1, 2, 4, 8, 0, 1, 2, 4, 0}
	request := c.Verb("POST").Prefix("backofftest").Suffix("abc")
	request.backoffMgr = &URLBackoff{
		Backoff: util.NewBackOff(
			time.Duration(1)*time.Second,
			time.Duration(200)*time.Second)}
	for _, sec := range seconds {
		start := time.Now()
		request.DoRaw()
		finish := time.Since(start)
		t.Logf("%v finished in %v", sec, finish)
		if finish < time.Duration(sec)*time.Second || finish >= time.Duration(sec+5)*time.Second {
			t.Fatalf("%v not in range %v", finish, sec)
		}
	}
}

// TestURLBackoffFunctionality generally tests the URLBackoff wrapper.  We avoid duplicating tests from backoff and request.
func TestURLBackoffFunctionality(t *testing.T) {
	myBackoff := &URLBackoff{
		Backoff: util.NewBackOff(1*time.Second, 60*time.Second),
	}

	// Now test that backoff increases, then recovers.
	// 200 and 300 should both result in clearing the backoff.
	// all others like 429 should result in increased backoff.
	seconds := []int{0,
		1, 2, 4, 8, 0,
		1, 2}
	returnCodes := []int{
		429, 500, 501, 502, 300,
		500, 501, 502,
	}

	if len(seconds) != len(returnCodes) {
		t.Fatalf("responseCode to backoff arrays should be the same length... sanity check failed.")
	}

	for i, sec := range seconds {
		backoffSec := myBackoff.CalculateBackoff(parse("http://1.2.3.4:100"))
		if backoffSec < time.Duration(sec)*time.Second || backoffSec > time.Duration(sec+5)*time.Second {
			t.Errorf("Backoff out of range %v: %v %v", i, sec, backoffSec)
		}
		myBackoff.UpdateBackoff(parse("http://1.2.3.4:100/responseCodeForFuncTest"), nil, returnCodes[i])
	}

	if myBackoff.CalculateBackoff(parse("http://1.2.3.4:100")) == 0 {
		t.Errorf("The final return code %v should have resulted in a backoff ! ", returnCodes[7])
	}
}

// readExpBackoffConfig handles the internal logic of determining what the
// backoff policy is.  By default if no information is available, NoBackoff.
// TODO Generalize this see #17727 .
func readExpBackoffConfig() BackoffManager {
	backoffBase := os.Getenv(envBackoffBase)
	backoffDuration := os.Getenv(envBackoffDuration)

	backoffBaseInt, errBase := strconv.ParseInt(backoffBase, 10, 64)
	backoffDurationInt, errDuration := strconv.ParseInt(backoffDuration, 10, 64)
	if errBase != nil || errDuration != nil {
		return &NoBackoff{}
	}
	return &URLBackoff{
		Backoff: util.NewBackOff(
			time.Duration(backoffBaseInt)*time.Second,
			time.Duration(backoffDurationInt)*time.Second)}
}

func TestURLBackoffFunctionalityCollisions(t *testing.T) {
	myBackoff := &URLBackoff{
		Backoff: util.NewBackOff(1*time.Second, 60*time.Second),
	}

	// Add some noise and make sure backoff for a clean URL is zero.
	myBackoff.UpdateBackoff(parse("http://100.200.300.400:8080"), nil, 500)

	myBackoff.UpdateBackoff(parse("http://1.2.3.4:8080"), nil, 500)

	if myBackoff.CalculateBackoff(parse("http://1.2.3.4:100")) > 0 {
		t.Errorf("URLs are colliding in the backoff map!")
	}
}

// readExpBackoffConfig handles the internal logic of determining what the
// backoff policy is.  By default if no information is available, NoBackoff.
// TODO Generalize this see #17727 .
func readExpBackoffConfig() BackoffManager {
	backoffBase := os.Getenv(envBackoffBase)
	backoffDuration := os.Getenv(envBackoffDuration)

	backoffBaseInt, errBase := strconv.ParseInt(backoffBase, 10, 64)
	backoffDurationInt, errDuration := strconv.ParseInt(backoffDuration, 10, 64)

	if errBase != nil || errDuration != nil {
		glog.V(2).Infof("Configuring no exponential backoff.")
		return &NoBackoff{}
	} else {
		glog.V(2).Infof("Configuring exponential backoff as %v, %v", backoffBaseInt, backoffDurationInt)
		return &URLBackoff{
			Backoff: util.NewBackOff(
				time.Duration(backoffBaseInt)*time.Second,
				time.Duration(backoffDurationInt)*time.Second)}
	}
}

// runSyncPod is a helper function to retrieve the running pods from the fake
// docker client and runs SyncPod for the given pod.
func runSyncPod(t *testing.T, dm *DockerManager, fakeDocker *FakeDockerClient, pod *api.Pod, backOff *util.Backoff, expectErr bool) kubecontainer.PodSyncResult {
	podStatus, err := dm.GetPodStatus(pod.UID, pod.Name, pod.Namespace)
	if err != nil {
		t.Errorf("unexpected error: %v", err)
	}
	fakeDocker.ClearCalls()
	if backOff == nil {
		backOff = util.NewBackOff(time.Second, time.Minute)
	}
	// api.PodStatus is not used in SyncPod now, pass in an empty one.
	result := dm.SyncPod(pod, api.PodStatus{}, podStatus, []api.Secret{}, backOff)
	err = result.Error()
	if err != nil && !expectErr {
		t.Errorf("unexpected error: %v", err)
	} else if err == nil && expectErr {
		t.Errorf("expected error didn't occur")
	}
	return result
}

func newTestDockerManagerWithHTTPClient(fakeHTTPClient *fakeHTTP) (*DockerManager, *FakeDockerClient) {
	fakeDocker := NewFakeDockerClient()
	fakeRecorder := &record.FakeRecorder{}
	containerRefManager := kubecontainer.NewRefManager()
	networkPlugin, _ := network.InitNetworkPlugin([]network.NetworkPlugin{}, "", network.NewFakeHost(nil))
	dockerManager := NewFakeDockerManager(
		fakeDocker,
		fakeRecorder,
		proberesults.NewManager(),
		containerRefManager,
		&cadvisorapi.MachineInfo{},
		kubetypes.PodInfraContainerImage,
		0, 0, "",
		kubecontainer.FakeOS{},
		networkPlugin,
		&fakeRuntimeHelper{},
		fakeHTTPClient,
		util.NewBackOff(time.Second, 300*time.Second))

	return dockerManager, fakeDocker
}

func TestSyncPodBackoff(t *testing.T) {
	var fakeClock = util.NewFakeClock(time.Now())
	startTime := fakeClock.Now()

	dm, fakeDocker := newTestDockerManager()
	containers := []api.Container{
		{Name: "good"},
		{Name: "bad"},
	}
	pod := &api.Pod{
		ObjectMeta: api.ObjectMeta{
			UID:       "12345678",
			Name:      "podfoo",
			Namespace: "nsnew",
		},
		Spec: api.PodSpec{
			Containers: containers,
		},
	}

	stableId := "k8s_bad." + strconv.FormatUint(kubecontainer.HashContainer(&containers[1]), 16) + "_podfoo_nsnew_12345678"
	dockerContainers := []*docker.Container{
		{
			ID:   "9876",
			Name: "/k8s_POD." + strconv.FormatUint(generatePodInfraContainerHash(pod), 16) + "_podfoo_nsnew_12345678_0",
			State: docker.State{
				StartedAt: startTime,
				Running:   true,
			},
		},
		{
			ID:   "1234",
			Name: "/k8s_good." + strconv.FormatUint(kubecontainer.HashContainer(&containers[0]), 16) + "_podfoo_nsnew_12345678_0",
			State: docker.State{
				StartedAt: startTime,
				Running:   true,
			},
		},
		{
			ID:   "5678",
			Name: "/k8s_bad." + strconv.FormatUint(kubecontainer.HashContainer(&containers[1]), 16) + "_podfoo_nsnew_12345678_0",
			State: docker.State{
				ExitCode:   42,
				StartedAt:  startTime,
				FinishedAt: fakeClock.Now(),
			},
		},
	}

	startCalls := []string{"inspect_container", "create", "start", "inspect_container"}
	backOffCalls := []string{"inspect_container"}
	startResult := &kubecontainer.SyncResult{kubecontainer.StartContainer, "bad", nil, ""}
	backoffResult := &kubecontainer.SyncResult{kubecontainer.StartContainer, "bad", kubecontainer.ErrCrashLoopBackOff, ""}
	tests := []struct {
		tick      int
		backoff   int
		killDelay int
		result    []string
		expectErr bool
	}{
		{1, 1, 1, startCalls, false},
		{2, 2, 2, startCalls, false},
		{3, 2, 3, backOffCalls, true},
		{4, 4, 4, startCalls, false},
		{5, 4, 5, backOffCalls, true},
		{6, 4, 6, backOffCalls, true},
		{7, 4, 7, backOffCalls, true},
		{8, 8, 129, startCalls, false},
		{130, 1, 0, startCalls, false},
	}

	backOff := util.NewBackOff(time.Second, time.Minute)
	backOff.Clock = fakeClock
	for _, c := range tests {
		fakeDocker.SetFakeContainers(dockerContainers)
		fakeClock.SetTime(startTime.Add(time.Duration(c.tick) * time.Second))

		result := runSyncPod(t, dm, fakeDocker, pod, backOff, c.expectErr)
		verifyCalls(t, fakeDocker, c.result)

		// Verify whether the correct sync pod result is generated
		if c.expectErr {
			verifySyncResults(t, []*kubecontainer.SyncResult{backoffResult}, result)
		} else {
			verifySyncResults(t, []*kubecontainer.SyncResult{startResult}, result)
		}

		if backOff.Get(stableId) != time.Duration(c.backoff)*time.Second {
			t.Errorf("At tick %s expected backoff=%s got=%s", time.Duration(c.tick)*time.Second, time.Duration(c.backoff)*time.Second, backOff.Get(stableId))
		}

		if len(fakeDocker.Created) > 0 {
			// pretend kill the container
			fakeDocker.Created = nil
			dockerContainers[2].State.FinishedAt = startTime.Add(time.Duration(c.killDelay) * time.Second)
		}
	}
}

func TestSerializedPuller(t *testing.T) {
	pod := &api.Pod{
		ObjectMeta: api.ObjectMeta{
			Name:            "test_pod",
			Namespace:       "test-ns",
			UID:             "bar",
			ResourceVersion: "42",
			SelfLink:        "/api/v1/pods/foo",
		}}

	cases := []struct {
		containerImage  string
		policy          api.PullPolicy
		calledFunctions []string
		inspectErr      error
		pullerErr       error
		expectedErr     []error
	}{
		{ // pull missing image
			containerImage:  "missing_image",
			policy:          api.PullIfNotPresent,
			calledFunctions: []string{"IsImagePresent", "PullImage"},
			inspectErr:      nil,
			pullerErr:       nil,
			expectedErr:     []error{nil}},

		{ // image present, dont pull
			containerImage:  "present_image",
			policy:          api.PullIfNotPresent,
			calledFunctions: []string{"IsImagePresent"},
			inspectErr:      nil,
			pullerErr:       nil,
			expectedErr:     []error{nil, nil, nil}},
		// image present, pull it
		{containerImage: "present_image",
			policy:          api.PullAlways,
			calledFunctions: []string{"IsImagePresent", "PullImage"},
			inspectErr:      nil,
			pullerErr:       nil,
			expectedErr:     []error{nil, nil, nil}},
		// missing image, error PullNever
		{containerImage: "missing_image",
			policy:          api.PullNever,
			calledFunctions: []string{"IsImagePresent"},
			inspectErr:      nil,
			pullerErr:       nil,
			expectedErr:     []error{ErrImageNeverPull, ErrImageNeverPull, ErrImageNeverPull}},
		// missing image, unable to inspect
		{containerImage: "missing_image",
			policy:          api.PullIfNotPresent,
			calledFunctions: []string{"IsImagePresent"},
			inspectErr:      errors.New("unknown inspectError"),
			pullerErr:       nil,
			expectedErr:     []error{ErrImageInspect, ErrImageInspect, ErrImageInspect}},
		// missing image, unable to fetch
		{containerImage: "typo_image",
			policy:          api.PullIfNotPresent,
			calledFunctions: []string{"IsImagePresent", "PullImage"},
			inspectErr:      nil,
			pullerErr:       errors.New("404"),
			expectedErr:     []error{ErrImagePull, ErrImagePull, ErrImagePullBackOff, ErrImagePull, ErrImagePullBackOff, ErrImagePullBackOff}},
	}

	for i, c := range cases {
		container := &api.Container{
			Name:            "container_name",
			Image:           c.containerImage,
			ImagePullPolicy: c.policy,
		}

		backOff := util.NewBackOff(time.Second, time.Minute)
		fakeClock := util.NewFakeClock(time.Now())
		backOff.Clock = fakeClock

		fakeRuntime := &FakeRuntime{}
		fakeRecorder := &record.FakeRecorder{}
		puller := NewSerializedImagePuller(fakeRecorder, fakeRuntime, backOff)

		fakeRuntime.ImageList = []Image{{"present_image", nil, 0}}
		fakeRuntime.Err = c.pullerErr
		fakeRuntime.InspectErr = c.inspectErr

		for tick, expected := range c.expectedErr {
			fakeClock.Step(time.Second)
			err, _ := puller.PullImage(pod, container, nil)
			fakeRuntime.AssertCalls(c.calledFunctions)
			assert.Equal(t, expected, err, "in test %d tick=%d", i, tick)
		}

	}
}

// Disable makes the backoff trivial, i.e., sets it to zero.  This might be used
// by tests which want to run 1000s of mock requests without slowing down.
func (b *URLBackoff) Disable() {
	glog.V(4).Infof("Disabling backoff strategy")
	b.Backoff = util.NewBackOff(0*time.Second, 0*time.Second)
}