// Get cgroup and networking stats of the specified container
func GetStats(cgroupManager cgroups.Manager, rootFs string, pid int, ignoreMetrics container.MetricSet) (*info.ContainerStats, error) {
	cgroupStats, err := cgroupManager.GetStats()
	if err != nil {
		return nil, err
	}
	libcontainerStats := &libcontainer.Stats{
		CgroupStats: cgroupStats,
	}
	stats := toContainerStats(libcontainerStats)

	// If we know the pid then get network stats from /proc/<pid>/net/dev
	if pid == 0 {
		return stats, nil
	}
	if !ignoreMetrics.Has(container.NetworkUsageMetrics) {
		netStats, err := networkStatsFromProc(rootFs, pid)
		if err != nil {
			glog.V(2).Infof("Unable to get network stats from pid %d: %v", pid, err)
		} else {
			stats.Network.Interfaces = append(stats.Network.Interfaces, netStats...)
		}
	}
	if !ignoreMetrics.Has(container.NetworkTcpUsageMetrics) {
		t, err := tcpStatsFromProc(rootFs, pid, "net/tcp")
		if err != nil {
			glog.V(2).Infof("Unable to get tcp stats from pid %d: %v", pid, err)
		} else {
			stats.Network.Tcp = t
		}

		t6, err := tcpStatsFromProc(rootFs, pid, "net/tcp6")
		if err != nil {
			glog.V(2).Infof("Unable to get tcp6 stats from pid %d: %v", pid, err)
		} else {
			stats.Network.Tcp6 = t6
		}
	}

	// For backwards compatibility.
	if len(stats.Network.Interfaces) > 0 {
		stats.Network.InterfaceStats = stats.Network.Interfaces[0]
	}

	return stats, nil
}

func newDockerContainerHandler(
	client *docker.Client,
	name string,
	machineInfoFactory info.MachineInfoFactory,
	fsInfo fs.FsInfo,
	storageDriver storageDriver,
	storageDir string,
	cgroupSubsystems *containerlibcontainer.CgroupSubsystems,
	inHostNamespace bool,
	metadataEnvs []string,
	dockerVersion []int,
	ignoreMetrics container.MetricSet,
) (container.ContainerHandler, error) {
	// Create the cgroup paths.
	cgroupPaths := make(map[string]string, len(cgroupSubsystems.MountPoints))
	for key, val := range cgroupSubsystems.MountPoints {
		cgroupPaths[key] = path.Join(val, name)
	}

	// Generate the equivalent cgroup manager for this container.
	cgroupManager := &cgroupfs.Manager{
		Cgroups: &libcontainerconfigs.Cgroup{
			Name: name,
		},
		Paths: cgroupPaths,
	}

	rootFs := "/"
	if !inHostNamespace {
		rootFs = "/rootfs"
		storageDir = path.Join(rootFs, storageDir)
	}

	id := ContainerNameToDockerId(name)

	// Add the Containers dir where the log files are stored.
	// FIXME: Give `otherStorageDir` a more descriptive name.
	otherStorageDir := path.Join(storageDir, pathToContainersDir, id)

	rwLayerID, err := getRwLayerID(id, storageDir, storageDriver, dockerVersion)
	if err != nil {
		return nil, err
	}
	var rootfsStorageDir string
	switch storageDriver {
	case aufsStorageDriver:
		rootfsStorageDir = path.Join(storageDir, string(aufsStorageDriver), aufsRWLayer, rwLayerID)
	case overlayStorageDriver:
		rootfsStorageDir = path.Join(storageDir, string(overlayStorageDriver), rwLayerID)
	}

	handler := &dockerContainerHandler{
		id:                 id,
		client:             client,
		name:               name,
		machineInfoFactory: machineInfoFactory,
		cgroupPaths:        cgroupPaths,
		cgroupManager:      cgroupManager,
		storageDriver:      storageDriver,
		fsInfo:             fsInfo,
		rootFs:             rootFs,
		rootfsStorageDir:   rootfsStorageDir,
		envs:               make(map[string]string),
		ignoreMetrics:      ignoreMetrics,
	}

	if !ignoreMetrics.Has(container.DiskUsageMetrics) {
		handler.fsHandler = common.NewFsHandler(time.Minute, rootfsStorageDir, otherStorageDir, fsInfo)
	}

	// We assume that if Inspect fails then the container is not known to docker.
	ctnr, err := client.InspectContainer(id)
	if err != nil {
		return nil, fmt.Errorf("failed to inspect container %q: %v", id, err)
	}
	handler.creationTime = ctnr.Created
	handler.pid = ctnr.State.Pid

	// Add the name and bare ID as aliases of the container.
	handler.aliases = append(handler.aliases, strings.TrimPrefix(ctnr.Name, "/"), id)
	handler.labels = ctnr.Config.Labels
	handler.image = ctnr.Config.Image
	handler.networkMode = ctnr.HostConfig.NetworkMode

	// split env vars to get metadata map.
	for _, exposedEnv := range metadataEnvs {
		for _, envVar := range ctnr.Config.Env {
			splits := strings.SplitN(envVar, "=", 2)
			if splits[0] == exposedEnv {
				handler.envs[strings.ToLower(exposedEnv)] = splits[1]
			}
		}
	}

	return handler, nil
}

func newRktContainerHandler(name string, rktClient rktapi.PublicAPIClient, rktPath string, cgroupSubsystems *libcontainer.CgroupSubsystems, machineInfoFactory info.MachineInfoFactory, fsInfo fs.FsInfo, rootFs string, ignoreMetrics container.MetricSet) (container.ContainerHandler, error) {
	aliases := make([]string, 1)
	isPod := false

	apiPod := &rktapi.Pod{}

	parsed, err := parseName(name)
	if err != nil {
		return nil, fmt.Errorf("this should be impossible!, new handler failing, but factory allowed, name = %s", name)
	}

	//rktnetes uses containerID: rkt://fff40827-b994-4e3a-8f88-6427c2c8a5ac:nginx
	if parsed.Container == "" {
		isPod = true
		aliases = append(aliases, "rkt://"+parsed.Pod)
	} else {
		aliases = append(aliases, "rkt://"+parsed.Pod+":"+parsed.Container)
	}

	pid := os.Getpid()
	labels := make(map[string]string)
	resp, err := rktClient.InspectPod(context.Background(), &rktapi.InspectPodRequest{
		Id: parsed.Pod,
	})
	if err != nil {
		return nil, err
	} else {
		var annotations []*rktapi.KeyValue
		if parsed.Container == "" {
			pid = int(resp.Pod.Pid)
			apiPod = resp.Pod
			annotations = resp.Pod.Annotations
		} else {
			var ok bool
			if annotations, ok = findAnnotations(resp.Pod.Apps, parsed.Container); !ok {
				glog.Warningf("couldn't find application in Pod matching %v", parsed.Container)
			}
		}
		labels = createLabels(annotations)
	}

	cgroupPaths := common.MakeCgroupPaths(cgroupSubsystems.MountPoints, name)

	// Generate the equivalent cgroup manager for this container.
	cgroupManager := &cgroupfs.Manager{
		Cgroups: &configs.Cgroup{
			Name: name,
		},
		Paths: cgroupPaths,
	}

	hasNetwork := false
	if isPod {
		hasNetwork = true
	}

	rootfsStorageDir := getRootFs(rktPath, parsed)

	handler := &rktContainerHandler{
		name:               name,
		rktClient:          rktClient,
		cgroupSubsystems:   cgroupSubsystems,
		machineInfoFactory: machineInfoFactory,
		cgroupPaths:        cgroupPaths,
		cgroupManager:      cgroupManager,
		fsInfo:             fsInfo,
		hasNetwork:         hasNetwork,
		rootFs:             rootFs,
		isPod:              isPod,
		aliases:            aliases,
		pid:                pid,
		labels:             labels,
		rootfsStorageDir:   rootfsStorageDir,
		ignoreMetrics:      ignoreMetrics,
		apiPod:             apiPod,
	}

	if !ignoreMetrics.Has(container.DiskUsageMetrics) {
		handler.fsHandler = common.NewFsHandler(time.Minute, rootfsStorageDir, "", fsInfo)
	}

	return handler, nil
}

// newDockerContainerHandler returns a new container.ContainerHandler
func newDockerContainerHandler(
	client *docker.Client,
	name string,
	machineInfoFactory info.MachineInfoFactory,
	fsInfo fs.FsInfo,
	storageDriver storageDriver,
	storageDir string,
	cgroupSubsystems *containerlibcontainer.CgroupSubsystems,
	inHostNamespace bool,
	metadataEnvs []string,
	dockerVersion []int,
	ignoreMetrics container.MetricSet,
	thinPoolWatcher *devicemapper.ThinPoolWatcher,
) (container.ContainerHandler, error) {
	// Create the cgroup paths.
	cgroupPaths := make(map[string]string, len(cgroupSubsystems.MountPoints))
	for key, val := range cgroupSubsystems.MountPoints {
		cgroupPaths[key] = path.Join(val, name)
	}

	// Generate the equivalent cgroup manager for this container.
	cgroupManager := &cgroupfs.Manager{
		Cgroups: &libcontainerconfigs.Cgroup{
			Name: name,
		},
		Paths: cgroupPaths,
	}

	rootFs := "/"
	if !inHostNamespace {
		rootFs = "/rootfs"
		storageDir = path.Join(rootFs, storageDir)
	}

	id := ContainerNameToDockerId(name)

	// Add the Containers dir where the log files are stored.
	// FIXME: Give `otherStorageDir` a more descriptive name.
	otherStorageDir := path.Join(storageDir, pathToContainersDir, id)

	rwLayerID, err := getRwLayerID(id, storageDir, storageDriver, dockerVersion)
	if err != nil {
		return nil, err
	}

	// Determine the rootfs storage dir OR the pool name to determine the device
	var (
		rootfsStorageDir string
		poolName         string
	)
	switch storageDriver {
	case aufsStorageDriver:
		rootfsStorageDir = path.Join(storageDir, string(aufsStorageDriver), aufsRWLayer, rwLayerID)
	case overlayStorageDriver:
		rootfsStorageDir = path.Join(storageDir, string(overlayStorageDriver), rwLayerID)
	case devicemapperStorageDriver:
		status, err := Status()
		if err != nil {
			return nil, fmt.Errorf("unable to determine docker status: %v", err)
		}

		poolName = status.DriverStatus[dockerutil.DriverStatusPoolName]
	}

	// TODO: extract object mother method
	handler := &dockerContainerHandler{
		id:                 id,
		client:             client,
		name:               name,
		machineInfoFactory: machineInfoFactory,
		cgroupPaths:        cgroupPaths,
		cgroupManager:      cgroupManager,
		storageDriver:      storageDriver,
		fsInfo:             fsInfo,
		rootFs:             rootFs,
		poolName:           poolName,
		rootfsStorageDir:   rootfsStorageDir,
		envs:               make(map[string]string),
		ignoreMetrics:      ignoreMetrics,
		thinPoolWatcher:    thinPoolWatcher,
	}

	// We assume that if Inspect fails then the container is not known to docker.
	ctnr, err := client.ContainerInspect(context.Background(), id)
	if err != nil {
		return nil, fmt.Errorf("failed to inspect container %q: %v", id, err)
	}
	// Timestamp returned by Docker is in time.RFC3339Nano format.
	handler.creationTime, err = time.Parse(time.RFC3339Nano, ctnr.Created)
	if err != nil {
		// This should not happen, report the error just in case
		return nil, fmt.Errorf("failed to parse the create timestamp %q for container %q: %v", ctnr.Created, id, err)
	}
	handler.pid = ctnr.State.Pid

	// Add the name and bare ID as aliases of the container.
	handler.aliases = append(handler.aliases, strings.TrimPrefix(ctnr.Name, "/"), id)
	handler.labels = ctnr.Config.Labels
	handler.image = ctnr.Config.Image
//.........这里部分代码省略.........