Golang String.Len方法代碼示例

// Index returns a list of items that match on the index function
// Index is thread-safe so long as you treat all items as immutable
func (c *threadSafeMap) Index(indexName string, obj interface{}) ([]interface{}, error) {
	c.lock.RLock()
	defer c.lock.RUnlock()

	indexFunc := c.indexers[indexName]
	if indexFunc == nil {
		return nil, fmt.Errorf("Index with name %s does not exist", indexName)
	}

	indexKeys, err := indexFunc(obj)
	if err != nil {
		return nil, err
	}
	index := c.indices[indexName]

	// need to de-dupe the return list.  Since multiple keys are allowed, this can happen.
	returnKeySet := sets.String{}
	for _, indexKey := range indexKeys {
		set := index[indexKey]
		for _, key := range set.UnsortedList() {
			returnKeySet.Insert(key)
		}
	}

	list := make([]interface{}, 0, returnKeySet.Len())
	for absoluteKey := range returnKeySet {
		list = append(list, c.items[absoluteKey])
	}
	return list, nil
}

func runResourceTrackingTest(f *framework.Framework, podsPerNode int, nodeNames sets.String, rm *framework.ResourceMonitor,
	expectedCPU map[string]map[float64]float64, expectedMemory framework.ResourceUsagePerContainer) {
	numNodes := nodeNames.Len()
	totalPods := podsPerNode * numNodes
	By(fmt.Sprintf("Creating a RC of %d pods and wait until all pods of this RC are running", totalPods))
	rcName := fmt.Sprintf("resource%d-%s", totalPods, string(uuid.NewUUID()))

	// TODO: Use a more realistic workload
	Expect(framework.RunRC(testutils.RCConfig{
		Client:         f.ClientSet,
		InternalClient: f.InternalClientset,
		Name:           rcName,
		Namespace:      f.Namespace.Name,
		Image:          framework.GetPauseImageName(f.ClientSet),
		Replicas:       totalPods,
	})).NotTo(HaveOccurred())

	// Log once and flush the stats.
	rm.LogLatest()
	rm.Reset()

	By("Start monitoring resource usage")
	// Periodically dump the cpu summary until the deadline is met.
	// Note that without calling framework.ResourceMonitor.Reset(), the stats
	// would occupy increasingly more memory. This should be fine
	// for the current test duration, but we should reclaim the
	// entries if we plan to monitor longer (e.g., 8 hours).
	deadline := time.Now().Add(monitoringTime)
	for time.Now().Before(deadline) {
		timeLeft := deadline.Sub(time.Now())
		framework.Logf("Still running...%v left", timeLeft)
		if timeLeft < reportingPeriod {
			time.Sleep(timeLeft)
		} else {
			time.Sleep(reportingPeriod)
		}
		logPodsOnNodes(f.ClientSet, nodeNames.List())
	}

	By("Reporting overall resource usage")
	logPodsOnNodes(f.ClientSet, nodeNames.List())
	usageSummary, err := rm.GetLatest()
	Expect(err).NotTo(HaveOccurred())
	// TODO(random-liu): Remove the original log when we migrate to new perfdash
	framework.Logf("%s", rm.FormatResourceUsage(usageSummary))
	// Log perf result
	framework.PrintPerfData(framework.ResourceUsageToPerfData(rm.GetMasterNodeLatest(usageSummary)))
	verifyMemoryLimits(f.ClientSet, expectedMemory, usageSummary)

	cpuSummary := rm.GetCPUSummary()
	framework.Logf("%s", rm.FormatCPUSummary(cpuSummary))
	// Log perf result
	framework.PrintPerfData(framework.CPUUsageToPerfData(rm.GetMasterNodeCPUSummary(cpuSummary)))
	verifyCPULimits(expectedCPU, cpuSummary)

	By("Deleting the RC")
	framework.DeleteRCAndPods(f.ClientSet, f.InternalClientset, f.Namespace.Name, rcName)
}

// DialFromContainers executes a curl via kubectl exec in a test container,
// which might then translate to a tcp or udp request based on the protocol
// argument in the url.
// - minTries is the minimum number of curl attempts required before declaring
//   success. Set to 0 if you'd like to return as soon as all endpoints respond
//   at least once.
// - maxTries is the maximum number of curl attempts. If this many attempts pass
//   and we don't see all expected endpoints, the test fails.
// - expectedEps is the set of endpointnames to wait for. Typically this is also
//   the hostname reported by each pod in the service through /hostName.
// maxTries == minTries will confirm that we see the expected endpoints and no
// more for maxTries. Use this if you want to eg: fail a readiness check on a
// pod and confirm it doesn't show up as an endpoint.
func (config *NetworkingTestConfig) DialFromContainer(protocol, containerIP, targetIP string, containerHttpPort, targetPort, maxTries, minTries int, expectedEps sets.String) {
	cmd := fmt.Sprintf("curl -q -s 'http://%s:%d/dial?request=hostName&protocol=%s&host=%s&port=%d&tries=1'",
		containerIP,
		containerHttpPort,
		protocol,
		targetIP,
		targetPort)

	eps := sets.NewString()

	for i := 0; i < maxTries; i++ {
		stdout, stderr, err := config.f.ExecShellInPodWithFullOutput(config.HostTestContainerPod.Name, cmd)
		if err != nil {
			// A failure to kubectl exec counts as a try, not a hard fail.
			// Also note that we will keep failing for maxTries in tests where
			// we confirm unreachability.
			Logf("Failed to execute %q: %v, stdout: %q, stderr %q", cmd, err, stdout, stderr)
		} else {
			var output map[string][]string
			if err := json.Unmarshal([]byte(stdout), &output); err != nil {
				Logf("WARNING: Failed to unmarshal curl response. Cmd %v run in %v, output: %s, err: %v",
					cmd, config.HostTestContainerPod.Name, stdout, err)
				continue
			}

			for _, hostName := range output["responses"] {
				trimmed := strings.TrimSpace(hostName)
				if trimmed != "" {
					eps.Insert(trimmed)
				}
			}
		}
		Logf("Waiting for endpoints: %v", expectedEps.Difference(eps))

		// Check against i+1 so we exit if minTries == maxTries.
		if (eps.Equal(expectedEps) || eps.Len() == 0 && expectedEps.Len() == 0) && i+1 >= minTries {
			return
		}
		// TODO: get rid of this delay #36281
		time.Sleep(hitEndpointRetryDelay)
	}

	config.diagnoseMissingEndpoints(eps)
	Failf("Failed to find expected endpoints:\nTries %d\nCommand %v\nretrieved %v\nexpected %v\n", minTries, cmd, eps, expectedEps)
}

// DialFromNode executes a tcp or udp request based on protocol via kubectl exec
// in a test container running with host networking.
// - minTries is the minimum number of curl attempts required before declaring
//   success. Set to 0 if you'd like to return as soon as all endpoints respond
//   at least once.
// - maxTries is the maximum number of curl attempts. If this many attempts pass
//   and we don't see all expected endpoints, the test fails.
// maxTries == minTries will confirm that we see the expected endpoints and no
// more for maxTries. Use this if you want to eg: fail a readiness check on a
// pod and confirm it doesn't show up as an endpoint.
func (config *NetworkingTestConfig) DialFromNode(protocol, targetIP string, targetPort, maxTries, minTries int, expectedEps sets.String) {
	var cmd string
	if protocol == "udp" {
		// TODO: It would be enough to pass 1s+epsilon to timeout, but unfortunately
		// busybox timeout doesn't support non-integer values.
		cmd = fmt.Sprintf("echo 'hostName' | timeout -t 2 nc -w 1 -u %s %d", targetIP, targetPort)
	} else {
		cmd = fmt.Sprintf("timeout -t 15 curl -q -s --connect-timeout 1 http://%s:%d/hostName", targetIP, targetPort)
	}

	// TODO: This simply tells us that we can reach the endpoints. Check that
	// the probability of hitting a specific endpoint is roughly the same as
	// hitting any other.
	eps := sets.NewString()

	filterCmd := fmt.Sprintf("%s | grep -v '^\\s*$'", cmd)
	for i := 0; i < maxTries; i++ {
		stdout, stderr, err := config.f.ExecShellInPodWithFullOutput(config.HostTestContainerPod.Name, filterCmd)
		if err != nil || len(stderr) > 0 {
			// A failure to exec command counts as a try, not a hard fail.
			// Also note that we will keep failing for maxTries in tests where
			// we confirm unreachability.
			Logf("Failed to execute %q: %v, stdout: %q, stderr: %q", filterCmd, err, stdout, stderr)
		} else {
			trimmed := strings.TrimSpace(stdout)
			if trimmed != "" {
				eps.Insert(trimmed)
			}
		}
		Logf("Waiting for %+v endpoints, got endpoints %+v", expectedEps.Difference(eps), eps)

		// Check against i+1 so we exit if minTries == maxTries.
		if (eps.Equal(expectedEps) || eps.Len() == 0 && expectedEps.Len() == 0) && i+1 >= minTries {
			return
		}
		// TODO: get rid of this delay #36281
		time.Sleep(hitEndpointRetryDelay)
	}

	config.diagnoseMissingEndpoints(eps)
	Failf("Failed to find expected endpoints:\nTries %d\nCommand %v\nretrieved %v\nexpected %v\n", minTries, cmd, eps, expectedEps)
}

func TestHammerController(t *testing.T) {
	// This test executes a bunch of requests through the fake source and
	// controller framework to make sure there's no locking/threading
	// errors. If an error happens, it should hang forever or trigger the
	// race detector.

	// source simulates an apiserver object endpoint.
	source := fcache.NewFakeControllerSource()

	// Let's do threadsafe output to get predictable test results.
	outputSetLock := sync.Mutex{}
	// map of key to operations done on the key
	outputSet := map[string][]string{}

	recordFunc := func(eventType string, obj interface{}) {
		key, err := DeletionHandlingMetaNamespaceKeyFunc(obj)
		if err != nil {
			t.Errorf("something wrong with key: %v", err)
			key = "oops something went wrong with the key"
		}

		// Record some output when items are deleted.
		outputSetLock.Lock()
		defer outputSetLock.Unlock()
		outputSet[key] = append(outputSet[key], eventType)
	}

	// Make a controller which just logs all the changes it gets.
	_, controller := NewInformer(
		source,
		&v1.Pod{},
		time.Millisecond*100,
		ResourceEventHandlerFuncs{
			AddFunc:    func(obj interface{}) { recordFunc("add", obj) },
			UpdateFunc: func(oldObj, newObj interface{}) { recordFunc("update", newObj) },
			DeleteFunc: func(obj interface{}) { recordFunc("delete", obj) },
		},
	)

	if controller.HasSynced() {
		t.Errorf("Expected HasSynced() to return false before we started the controller")
	}

	// Run the controller and run it until we close stop.
	stop := make(chan struct{})
	go controller.Run(stop)

	// Let's wait for the controller to do its initial sync
	wait.Poll(100*time.Millisecond, wait.ForeverTestTimeout, func() (bool, error) {
		return controller.HasSynced(), nil
	})
	if !controller.HasSynced() {
		t.Errorf("Expected HasSynced() to return true after the initial sync")
	}

	wg := sync.WaitGroup{}
	const threads = 3
	wg.Add(threads)
	for i := 0; i < threads; i++ {
		go func() {
			defer wg.Done()
			// Let's add a few objects to the source.
			currentNames := sets.String{}
			rs := rand.NewSource(rand.Int63())
			f := fuzz.New().NilChance(.5).NumElements(0, 2).RandSource(rs)
			r := rand.New(rs) // Mustn't use r and f concurrently!
			for i := 0; i < 100; i++ {
				var name string
				var isNew bool
				if currentNames.Len() == 0 || r.Intn(3) == 1 {
					f.Fuzz(&name)
					isNew = true
				} else {
					l := currentNames.List()
					name = l[r.Intn(len(l))]
				}

				pod := &v1.Pod{}
				f.Fuzz(pod)
				pod.ObjectMeta.Name = name
				pod.ObjectMeta.Namespace = "default"
				// Add, update, or delete randomly.
				// Note that these pods are not valid-- the fake source doesn't
				// call validation or perform any other checking.
				if isNew {
					currentNames.Insert(name)
					source.Add(pod)
					continue
				}
				switch r.Intn(2) {
				case 0:
					currentNames.Insert(name)
					source.Modify(pod)
				case 1:
					currentNames.Delete(name)
					source.Delete(pod)
				}
			}
		}()
	}
//.........這裏部分代碼省略.........