vendor/k8s.io/kubernetes/pkg/kubectl/cmd/cp/cp.go - cloudstack-kubernetes-provider - Git at Google

 /*
 Copyright 2016 The Kubernetes Authors.

 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 cp

 import (
 	"archive/tar"
 	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
 	"os"
 	"path"
 	"path/filepath"
 	"strings"

 	"k8s.io/cli-runtime/pkg/genericclioptions"
 	"k8s.io/client-go/kubernetes"
 	restclient "k8s.io/client-go/rest"
 	"k8s.io/kubernetes/pkg/kubectl/cmd/exec"
 	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
 	"k8s.io/kubernetes/pkg/kubectl/util/i18n"
 	"k8s.io/kubernetes/pkg/kubectl/util/templates"

 	"bytes"

 	"github.com/renstrom/dedent"
 	"github.com/spf13/cobra"
 )

 var (
 	cpExample = templates.Examples(i18n.T(`
 		# !!!Important Note!!!
 		# Requires that the 'tar' binary is present in your container
 		# image.  If 'tar' is not present, 'kubectl cp' will fail.

 		# Copy /tmp/foo_dir local directory to /tmp/bar_dir in a remote pod in the default namespace
 		kubectl cp /tmp/foo_dir <some-pod>:/tmp/bar_dir

 		# Copy /tmp/foo local file to /tmp/bar in a remote pod in a specific container
 		kubectl cp /tmp/foo <some-pod>:/tmp/bar -c <specific-container>

 		# Copy /tmp/foo local file to /tmp/bar in a remote pod in namespace <some-namespace>
 		kubectl cp /tmp/foo <some-namespace>/<some-pod>:/tmp/bar

 		# Copy /tmp/foo from a remote pod to /tmp/bar locally
 		kubectl cp <some-namespace>/<some-pod>:/tmp/foo /tmp/bar`))

 	cpUsageStr = dedent.Dedent(`
 		expected 'cp <file-spec-src> <file-spec-dest> [-c container]'.
 		<file-spec> is:
 		[namespace/]pod-name:/file/path for a remote file
 		/file/path for a local file`)
 )

 type CopyOptions struct {
 	Container  string
 	Namespace  string
 	NoPreserve bool

 	ClientConfig *restclient.Config
 	Clientset    kubernetes.Interface

 	genericclioptions.IOStreams
 }

 func NewCopyOptions(ioStreams genericclioptions.IOStreams) *CopyOptions {
 	return &CopyOptions{
 		IOStreams: ioStreams,
 	}
 }

 // NewCmdCp creates a new Copy command.
 func NewCmdCp(f cmdutil.Factory, ioStreams genericclioptions.IOStreams) *cobra.Command {
 	o := NewCopyOptions(ioStreams)

 	cmd := &cobra.Command{
 		Use:                   "cp <file-spec-src> <file-spec-dest>",
 		DisableFlagsInUseLine: true,
 		Short:                 i18n.T("Copy files and directories to and from containers."),
 		Long:                  "Copy files and directories to and from containers.",
 		Example:               cpExample,
 		Run: func(cmd *cobra.Command, args []string) {
 			cmdutil.CheckErr(o.Complete(f, cmd))
 			cmdutil.CheckErr(o.Run(args))
 		},
 	}
 	cmd.Flags().StringVarP(&o.Container, "container", "c", o.Container, "Container name. If omitted, the first container in the pod will be chosen")
 	cmd.Flags().BoolVarP(&o.NoPreserve, "no-preserve", "", false, "The copied file/directory's ownership and permissions will not be preserved in the container")

 	return cmd
 }

 type fileSpec struct {
 	PodNamespace string
 	PodName      string
 	File         string
 }

 var (
 	errFileSpecDoesntMatchFormat = errors.New("Filespec must match the canonical format: [[namespace/]pod:]file/path")
 	errFileCannotBeEmpty         = errors.New("Filepath can not be empty")
 )

 func extractFileSpec(arg string) (fileSpec, error) {
 	if i := strings.Index(arg, ":"); i == -1 {
 		return fileSpec{File: arg}, nil
 	} else if i > 0 {
 		file := arg[i+1:]
 		pod := arg[:i]
 		pieces := strings.Split(pod, "/")
 		if len(pieces) == 1 {
 			return fileSpec{
 				PodName: pieces[0],
 				File:    file,
 			}, nil
 		}
 		if len(pieces) == 2 {
 			return fileSpec{
 				PodNamespace: pieces[0],
 				PodName:      pieces[1],
 				File:         file,
 			}, nil
 		}
 	}

 	return fileSpec{}, errFileSpecDoesntMatchFormat
 }

 func (o *CopyOptions) Complete(f cmdutil.Factory, cmd *cobra.Command) error {
 	var err error
 	o.Namespace, _, err = f.ToRawKubeConfigLoader().Namespace()
 	if err != nil {
 		return err
 	}

 	o.Clientset, err = f.KubernetesClientSet()
 	if err != nil {
 		return err
 	}

 	o.ClientConfig, err = f.ToRESTConfig()
 	if err != nil {
 		return err
 	}
 	return nil
 }

 func (o *CopyOptions) Validate(cmd *cobra.Command, args []string) error {
 	if len(args) != 2 {
 		return cmdutil.UsageErrorf(cmd, cpUsageStr)
 	}
 	return nil
 }

 func (o *CopyOptions) Run(args []string) error {
 	if len(args) < 2 {
 		return fmt.Errorf("source and destination are required")
 	}
 	srcSpec, err := extractFileSpec(args[0])
 	if err != nil {
 		return err
 	}
 	destSpec, err := extractFileSpec(args[1])
 	if err != nil {
 		return err
 	}

 	if len(srcSpec.PodName) != 0 && len(destSpec.PodName) != 0 {
 		if _, err := os.Stat(args[0]); err == nil {
 			return o.copyToPod(fileSpec{File: args[0]}, destSpec, &exec.ExecOptions{})
 		}
 		return fmt.Errorf("src doesn't exist in local filesystem")
 	}

 	if len(srcSpec.PodName) != 0 {
 		return o.copyFromPod(srcSpec, destSpec)
 	}
 	if len(destSpec.PodName) != 0 {
 		return o.copyToPod(srcSpec, destSpec, &exec.ExecOptions{})
 	}
 	return fmt.Errorf("one of src or dest must be a remote file specification")
 }

 // checkDestinationIsDir receives a destination fileSpec and
 // determines if the provided destination path exists on the
 // pod. If the destination path does not exist or is _not_ a
 // directory, an error is returned with the exit code received.
 func (o *CopyOptions) checkDestinationIsDir(dest fileSpec) error {
 	options := &exec.ExecOptions{
 		StreamOptions: exec.StreamOptions{
 			IOStreams: genericclioptions.IOStreams{
 				Out:    bytes.NewBuffer([]byte{}),
 				ErrOut: bytes.NewBuffer([]byte{}),
 			},

 			Namespace: dest.PodNamespace,
 			PodName:   dest.PodName,
 		},

 		Command:  []string{"test", "-d", dest.File},
 		Executor: &exec.DefaultRemoteExecutor{},
 	}

 	return o.execute(options)
 }

 func (o *CopyOptions) copyToPod(src, dest fileSpec, options *exec.ExecOptions) error {
 	if len(src.File) == 0 || len(dest.File) == 0 {
 		return errFileCannotBeEmpty
 	}
 	reader, writer := io.Pipe()

 	// strip trailing slash (if any)
 	if dest.File != "/" && strings.HasSuffix(string(dest.File[len(dest.File)-1]), "/") {
 		dest.File = dest.File[:len(dest.File)-1]
 	}

 	if err := o.checkDestinationIsDir(dest); err == nil {
 		// If no error, dest.File was found to be a directory.
 		// Copy specified src into it
 		dest.File = dest.File + "/" + path.Base(src.File)
 	}

 	go func() {
 		defer writer.Close()
 		err := makeTar(src.File, dest.File, writer)
 		cmdutil.CheckErr(err)
 	}()
 	var cmdArr []string

 	// TODO: Improve error messages by first testing if 'tar' is present in the container?
 	if o.NoPreserve {
 		cmdArr = []string{"tar", "--no-same-permissions", "--no-same-owner", "-xf", "-"}
 	} else {
 		cmdArr = []string{"tar", "-xf", "-"}
 	}
 	destDir := path.Dir(dest.File)
 	if len(destDir) > 0 {
 		cmdArr = append(cmdArr, "-C", destDir)
 	}

 	options.StreamOptions = exec.StreamOptions{
 		IOStreams: genericclioptions.IOStreams{
 			In:     reader,
 			Out:    o.Out,
 			ErrOut: o.ErrOut,
 		},
 		Stdin: true,

 		Namespace: dest.PodNamespace,
 		PodName:   dest.PodName,
 	}

 	options.Command = cmdArr
 	options.Executor = &exec.DefaultRemoteExecutor{}
 	return o.execute(options)
 }

 func (o *CopyOptions) copyFromPod(src, dest fileSpec) error {
 	if len(src.File) == 0 || len(dest.File) == 0 {
 		return errFileCannotBeEmpty
 	}

 	reader, outStream := io.Pipe()
 	options := &exec.ExecOptions{
 		StreamOptions: exec.StreamOptions{
 			IOStreams: genericclioptions.IOStreams{
 				In:     nil,
 				Out:    outStream,
 				ErrOut: o.Out,
 			},

 			Namespace: src.PodNamespace,
 			PodName:   src.PodName,
 		},

 		// TODO: Improve error messages by first testing if 'tar' is present in the container?
 		Command:  []string{"tar", "cf", "-", src.File},
 		Executor: &exec.DefaultRemoteExecutor{},
 	}

 	go func() {
 		defer outStream.Close()
 		o.execute(options)
 	}()
 	prefix := getPrefix(src.File)
 	prefix = path.Clean(prefix)
 	// remove extraneous path shortcuts - these could occur if a path contained extra "../"
 	// and attempted to navigate beyond "/" in a remote filesystem
 	prefix = stripPathShortcuts(prefix)
 	return untarAll(reader, dest.File, prefix)
 }

 // stripPathShortcuts removes any leading or trailing "../" from a given path
 func stripPathShortcuts(p string) string {
 	newPath := path.Clean(p)
 	trimmed := strings.TrimPrefix(newPath, "../")

 	for trimmed != newPath {
 		newPath = trimmed
 		trimmed = strings.TrimPrefix(newPath, "../")
 	}

 	// trim leftover ".."
 	if newPath == ".." {
 		newPath = ""
 	}

 	if len(newPath) > 0 && string(newPath[0]) == "/" {
 		return newPath[1:]
 	}

 	return newPath
 }

 func makeTar(srcPath, destPath string, writer io.Writer) error {
 	// TODO: use compression here?
 	tarWriter := tar.NewWriter(writer)
 	defer tarWriter.Close()

 	srcPath = path.Clean(srcPath)
 	destPath = path.Clean(destPath)
 	return recursiveTar(path.Dir(srcPath), path.Base(srcPath), path.Dir(destPath), path.Base(destPath), tarWriter)
 }

 func recursiveTar(srcBase, srcFile, destBase, destFile string, tw *tar.Writer) error {
 	filepath := path.Join(srcBase, srcFile)
 	stat, err := os.Lstat(filepath)
 	if err != nil {
 		return err
 	}
 	if stat.IsDir() {
 		files, err := ioutil.ReadDir(filepath)
 		if err != nil {
 			return err
 		}
 		if len(files) == 0 {
 			//case empty directory
 			hdr, _ := tar.FileInfoHeader(stat, filepath)
 			hdr.Name = destFile
 			if err := tw.WriteHeader(hdr); err != nil {
 				return err
 			}
 		}
 		for _, f := range files {
 			if err := recursiveTar(srcBase, path.Join(srcFile, f.Name()), destBase, path.Join(destFile, f.Name()), tw); err != nil {
 				return err
 			}
 		}
 		return nil
 	} else if stat.Mode()&os.ModeSymlink != 0 {
 		//case soft link
 		hdr, _ := tar.FileInfoHeader(stat, filepath)
 		target, err := os.Readlink(filepath)
 		if err != nil {
 			return err
 		}

 		hdr.Linkname = target
 		hdr.Name = destFile
 		if err := tw.WriteHeader(hdr); err != nil {
 			return err
 		}
 	} else {
 		//case regular file or other file type like pipe
 		hdr, err := tar.FileInfoHeader(stat, filepath)
 		if err != nil {
 			return err
 		}
 		hdr.Name = destFile

 		if err := tw.WriteHeader(hdr); err != nil {
 			return err
 		}

 		f, err := os.Open(filepath)
 		if err != nil {
 			return err
 		}
 		defer f.Close()

 		if _, err := io.Copy(tw, f); err != nil {
 			return err
 		}
 		return f.Close()
 	}
 	return nil
 }

 // clean prevents path traversals by stripping them out.
 // This is adapted from https://golang.org/src/net/http/fs.go#L74
 func clean(fileName string) string {
 	return path.Clean(string(os.PathSeparator) + fileName)
 }

 func untarAll(reader io.Reader, destFile, prefix string) error {
 	entrySeq := -1

 	// TODO: use compression here?
 	tarReader := tar.NewReader(reader)
 	for {
 		header, err := tarReader.Next()
 		if err != nil {
 			if err != io.EOF {
 				return err
 			}
 			break
 		}
 		entrySeq++
 		mode := header.FileInfo().Mode()
 		outFileName := path.Join(destFile, clean(header.Name[len(prefix):]))
 		baseName := path.Dir(outFileName)
 		if err := os.MkdirAll(baseName, 0755); err != nil {
 			return err
 		}
 		if header.FileInfo().IsDir() {
 			if err := os.MkdirAll(outFileName, 0755); err != nil {
 				return err
 			}
 			continue
 		}

 		// handle coping remote file into local directory
 		if entrySeq == 0 && !header.FileInfo().IsDir() {
 			exists, err := dirExists(outFileName)
 			if err != nil {
 				return err
 			}
 			if exists {
 				outFileName = filepath.Join(outFileName, path.Base(clean(header.Name)))
 			}
 		}

 		if mode&os.ModeSymlink != 0 {
 			err := os.Symlink(header.Linkname, outFileName)
 			if err != nil {
 				return err
 			}
 		} else {
 			outFile, err := os.Create(outFileName)
 			if err != nil {
 				return err
 			}
 			defer outFile.Close()
 			if _, err := io.Copy(outFile, tarReader); err != nil {
 				return err
 			}
 			if err := outFile.Close(); err != nil {
 				return err
 			}
 		}
 	}

 	if entrySeq == -1 {
 		//if no file was copied
 		errInfo := fmt.Sprintf("error: %s no such file or directory", prefix)
 		return errors.New(errInfo)
 	}
 	return nil
 }

 func getPrefix(file string) string {
 	// tar strips the leading '/' if it's there, so we will too
 	return strings.TrimLeft(file, "/")
 }

 func (o *CopyOptions) execute(options *exec.ExecOptions) error {
 	if len(options.Namespace) == 0 {
 		options.Namespace = o.Namespace
 	}

 	if len(o.Container) > 0 {
 		options.ContainerName = o.Container
 	}

 	options.Config = o.ClientConfig
 	options.PodClient = o.Clientset.Core()

 	if err := options.Validate(); err != nil {
 		return err
 	}

 	if err := options.Run(); err != nil {
 		return err
 	}
 	return nil
 }

 // dirExists checks if a path exists and is a directory.
 func dirExists(path string) (bool, error) {
 	fi, err := os.Stat(path)
 	if err == nil && fi.IsDir() {
 		return true, nil
 	}
 	if os.IsNotExist(err) {
 		return false, nil
 	}
 	return false, err
 }
	/*
	Copyright 2016 The Kubernetes Authors.

	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 cp

	import (
	"archive/tar"
	"errors"
	"fmt"
	"io"
	"io/ioutil"
	"os"
	"path"
	"path/filepath"
	"strings"

	"k8s.io/cli-runtime/pkg/genericclioptions"
	"k8s.io/client-go/kubernetes"
	restclient "k8s.io/client-go/rest"
	"k8s.io/kubernetes/pkg/kubectl/cmd/exec"
	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
	"k8s.io/kubernetes/pkg/kubectl/util/i18n"
	"k8s.io/kubernetes/pkg/kubectl/util/templates"

	"bytes"

	"github.com/renstrom/dedent"
	"github.com/spf13/cobra"
	)

	var (
	cpExample = templates.Examples(i18n.T(`
	# !!!Important Note!!!
	# Requires that the 'tar' binary is present in your container
	# image. If 'tar' is not present, 'kubectl cp' will fail.

	# Copy /tmp/foo_dir local directory to /tmp/bar_dir in a remote pod in the default namespace
	kubectl cp /tmp/foo_dir <some-pod>:/tmp/bar_dir

	# Copy /tmp/foo local file to /tmp/bar in a remote pod in a specific container
	kubectl cp /tmp/foo <some-pod>:/tmp/bar -c <specific-container>

	# Copy /tmp/foo local file to /tmp/bar in a remote pod in namespace <some-namespace>
	kubectl cp /tmp/foo <some-namespace>/<some-pod>:/tmp/bar

	# Copy /tmp/foo from a remote pod to /tmp/bar locally
	kubectl cp <some-namespace>/<some-pod>:/tmp/foo /tmp/bar`))

	cpUsageStr = dedent.Dedent(`
	expected 'cp <file-spec-src> <file-spec-dest> [-c container]'.
	<file-spec> is:
	[namespace/]pod-name:/file/path for a remote file
	/file/path for a local file`)
	)

	type CopyOptions struct {
	Container string
	Namespace string
	NoPreserve bool

	ClientConfig *restclient.Config
	Clientset kubernetes.Interface

	genericclioptions.IOStreams
	}

	func NewCopyOptions(ioStreams genericclioptions.IOStreams) *CopyOptions {
	return &CopyOptions{
	IOStreams: ioStreams,
	}
	}

	// NewCmdCp creates a new Copy command.
	func NewCmdCp(f cmdutil.Factory, ioStreams genericclioptions.IOStreams) *cobra.Command {
	o := NewCopyOptions(ioStreams)

	cmd := &cobra.Command{
	Use: "cp <file-spec-src> <file-spec-dest>",
	DisableFlagsInUseLine: true,
	Short: i18n.T("Copy files and directories to and from containers."),
	Long: "Copy files and directories to and from containers.",
	Example: cpExample,
	Run: func(cmd *cobra.Command, args []string) {
	cmdutil.CheckErr(o.Complete(f, cmd))
	cmdutil.CheckErr(o.Run(args))
	},
	}
	cmd.Flags().StringVarP(&o.Container, "container", "c", o.Container, "Container name. If omitted, the first container in the pod will be chosen")
	cmd.Flags().BoolVarP(&o.NoPreserve, "no-preserve", "", false, "The copied file/directory's ownership and permissions will not be preserved in the container")

	return cmd
	}

	type fileSpec struct {
	PodNamespace string
	PodName string
	File string
	}

	var (
	errFileSpecDoesntMatchFormat = errors.New("Filespec must match the canonical format: [[namespace/]pod:]file/path")
	errFileCannotBeEmpty = errors.New("Filepath can not be empty")
	)

	func extractFileSpec(arg string) (fileSpec, error) {
	if i := strings.Index(arg, ":"); i == -1 {
	return fileSpec{File: arg}, nil
	} else if i > 0 {
	file := arg[i+1:]
	pod := arg[:i]
	pieces := strings.Split(pod, "/")
	if len(pieces) == 1 {
	return fileSpec{
	PodName: pieces[0],
	File: file,
	}, nil
	}
	if len(pieces) == 2 {
	return fileSpec{
	PodNamespace: pieces[0],
	PodName: pieces[1],
	File: file,
	}, nil
	}
	}

	return fileSpec{}, errFileSpecDoesntMatchFormat
	}

	func (o CopyOptions) Complete(f cmdutil.Factory, cmd cobra.Command) error {
	var err error
	o.Namespace, _, err = f.ToRawKubeConfigLoader().Namespace()
	if err != nil {
	return err
	}

	o.Clientset, err = f.KubernetesClientSet()
	if err != nil {
	return err
	}

	o.ClientConfig, err = f.ToRESTConfig()
	if err != nil {
	return err
	}
	return nil
	}

	func (o CopyOptions) Validate(cmd cobra.Command, args []string) error {
	if len(args) != 2 {
	return cmdutil.UsageErrorf(cmd, cpUsageStr)
	}
	return nil
	}

	func (o *CopyOptions) Run(args []string) error {
	if len(args) < 2 {
	return fmt.Errorf("source and destination are required")
	}
	srcSpec, err := extractFileSpec(args[0])
	if err != nil {
	return err
	}
	destSpec, err := extractFileSpec(args[1])
	if err != nil {
	return err
	}

	if len(srcSpec.PodName) != 0 && len(destSpec.PodName) != 0 {
	if _, err := os.Stat(args[0]); err == nil {
	return o.copyToPod(fileSpec{File: args[0]}, destSpec, &exec.ExecOptions{})
	}
	return fmt.Errorf("src doesn't exist in local filesystem")
	}

	if len(srcSpec.PodName) != 0 {
	return o.copyFromPod(srcSpec, destSpec)
	}
	if len(destSpec.PodName) != 0 {
	return o.copyToPod(srcSpec, destSpec, &exec.ExecOptions{})
	}
	return fmt.Errorf("one of src or dest must be a remote file specification")
	}

	// checkDestinationIsDir receives a destination fileSpec and
	// determines if the provided destination path exists on the
	// pod. If the destination path does not exist or is _not_ a
	// directory, an error is returned with the exit code received.
	func (o *CopyOptions) checkDestinationIsDir(dest fileSpec) error {
	options := &exec.ExecOptions{
	StreamOptions: exec.StreamOptions{
	IOStreams: genericclioptions.IOStreams{
	Out: bytes.NewBuffer([]byte{}),
	ErrOut: bytes.NewBuffer([]byte{}),
	},

	Namespace: dest.PodNamespace,
	PodName: dest.PodName,
	},

	Command: []string{"test", "-d", dest.File},
	Executor: &exec.DefaultRemoteExecutor{},
	}

	return o.execute(options)
	}

	func (o CopyOptions) copyToPod(src, dest fileSpec, options exec.ExecOptions) error {
	if len(src.File) == 0 \|\| len(dest.File) == 0 {
	return errFileCannotBeEmpty
	}
	reader, writer := io.Pipe()

	// strip trailing slash (if any)
	if dest.File != "/" && strings.HasSuffix(string(dest.File[len(dest.File)-1]), "/") {
	dest.File = dest.File[:len(dest.File)-1]
	}

	if err := o.checkDestinationIsDir(dest); err == nil {
	// If no error, dest.File was found to be a directory.
	// Copy specified src into it
	dest.File = dest.File + "/" + path.Base(src.File)
	}

	go func() {
	defer writer.Close()
	err := makeTar(src.File, dest.File, writer)
	cmdutil.CheckErr(err)
	}()
	var cmdArr []string

	// TODO: Improve error messages by first testing if 'tar' is present in the container?
	if o.NoPreserve {
	cmdArr = []string{"tar", "--no-same-permissions", "--no-same-owner", "-xf", "-"}
	} else {
	cmdArr = []string{"tar", "-xf", "-"}
	}
	destDir := path.Dir(dest.File)
	if len(destDir) > 0 {
	cmdArr = append(cmdArr, "-C", destDir)
	}

	options.StreamOptions = exec.StreamOptions{
	IOStreams: genericclioptions.IOStreams{
	In: reader,
	Out: o.Out,
	ErrOut: o.ErrOut,
	},
	Stdin: true,

	Namespace: dest.PodNamespace,
	PodName: dest.PodName,
	}

	options.Command = cmdArr
	options.Executor = &exec.DefaultRemoteExecutor{}
	return o.execute(options)
	}

	func (o *CopyOptions) copyFromPod(src, dest fileSpec) error {
	if len(src.File) == 0 \|\| len(dest.File) == 0 {
	return errFileCannotBeEmpty
	}

	reader, outStream := io.Pipe()
	options := &exec.ExecOptions{
	StreamOptions: exec.StreamOptions{
	IOStreams: genericclioptions.IOStreams{
	In: nil,
	Out: outStream,
	ErrOut: o.Out,
	},

	Namespace: src.PodNamespace,
	PodName: src.PodName,
	},

	// TODO: Improve error messages by first testing if 'tar' is present in the container?
	Command: []string{"tar", "cf", "-", src.File},
	Executor: &exec.DefaultRemoteExecutor{},
	}

	go func() {
	defer outStream.Close()
	o.execute(options)
	}()
	prefix := getPrefix(src.File)
	prefix = path.Clean(prefix)
	// remove extraneous path shortcuts - these could occur if a path contained extra "../"
	// and attempted to navigate beyond "/" in a remote filesystem
	prefix = stripPathShortcuts(prefix)
	return untarAll(reader, dest.File, prefix)
	}

	// stripPathShortcuts removes any leading or trailing "../" from a given path
	func stripPathShortcuts(p string) string {
	newPath := path.Clean(p)
	trimmed := strings.TrimPrefix(newPath, "../")

	for trimmed != newPath {
	newPath = trimmed
	trimmed = strings.TrimPrefix(newPath, "../")
	}

	// trim leftover ".."
	if newPath == ".." {
	newPath = ""
	}

	if len(newPath) > 0 && string(newPath[0]) == "/" {
	return newPath[1:]
	}

	return newPath
	}

	func makeTar(srcPath, destPath string, writer io.Writer) error {
	// TODO: use compression here?
	tarWriter := tar.NewWriter(writer)
	defer tarWriter.Close()

	srcPath = path.Clean(srcPath)
	destPath = path.Clean(destPath)
	return recursiveTar(path.Dir(srcPath), path.Base(srcPath), path.Dir(destPath), path.Base(destPath), tarWriter)
	}

	func recursiveTar(srcBase, srcFile, destBase, destFile string, tw *tar.Writer) error {
	filepath := path.Join(srcBase, srcFile)
	stat, err := os.Lstat(filepath)
	if err != nil {
	return err
	}
	if stat.IsDir() {
	files, err := ioutil.ReadDir(filepath)
	if err != nil {
	return err
	}
	if len(files) == 0 {
	//case empty directory
	hdr, _ := tar.FileInfoHeader(stat, filepath)
	hdr.Name = destFile
	if err := tw.WriteHeader(hdr); err != nil {
	return err
	}
	}
	for _, f := range files {
	if err := recursiveTar(srcBase, path.Join(srcFile, f.Name()), destBase, path.Join(destFile, f.Name()), tw); err != nil {
	return err
	}
	}
	return nil
	} else if stat.Mode()&os.ModeSymlink != 0 {
	//case soft link
	hdr, _ := tar.FileInfoHeader(stat, filepath)
	target, err := os.Readlink(filepath)
	if err != nil {
	return err
	}

	hdr.Linkname = target
	hdr.Name = destFile
	if err := tw.WriteHeader(hdr); err != nil {
	return err
	}
	} else {
	//case regular file or other file type like pipe
	hdr, err := tar.FileInfoHeader(stat, filepath)
	if err != nil {
	return err
	}
	hdr.Name = destFile

	if err := tw.WriteHeader(hdr); err != nil {
	return err
	}

	f, err := os.Open(filepath)
	if err != nil {
	return err
	}
	defer f.Close()

	if _, err := io.Copy(tw, f); err != nil {
	return err
	}
	return f.Close()
	}
	return nil
	}

	// clean prevents path traversals by stripping them out.
	// This is adapted from https://golang.org/src/net/http/fs.go#L74
	func clean(fileName string) string {
	return path.Clean(string(os.PathSeparator) + fileName)
	}

	func untarAll(reader io.Reader, destFile, prefix string) error {
	entrySeq := -1

	// TODO: use compression here?
	tarReader := tar.NewReader(reader)
	for {
	header, err := tarReader.Next()
	if err != nil {
	if err != io.EOF {
	return err
	}
	break
	}
	entrySeq++
	mode := header.FileInfo().Mode()
	outFileName := path.Join(destFile, clean(header.Name[len(prefix):]))
	baseName := path.Dir(outFileName)
	if err := os.MkdirAll(baseName, 0755); err != nil {
	return err
	}
	if header.FileInfo().IsDir() {
	if err := os.MkdirAll(outFileName, 0755); err != nil {
	return err
	}
	continue
	}

	// handle coping remote file into local directory
	if entrySeq == 0 && !header.FileInfo().IsDir() {
	exists, err := dirExists(outFileName)
	if err != nil {
	return err
	}
	if exists {
	outFileName = filepath.Join(outFileName, path.Base(clean(header.Name)))
	}
	}

	if mode&os.ModeSymlink != 0 {
	err := os.Symlink(header.Linkname, outFileName)
	if err != nil {
	return err
	}
	} else {
	outFile, err := os.Create(outFileName)
	if err != nil {
	return err
	}
	defer outFile.Close()
	if _, err := io.Copy(outFile, tarReader); err != nil {
	return err
	}
	if err := outFile.Close(); err != nil {
	return err
	}
	}
	}

	if entrySeq == -1 {
	//if no file was copied
	errInfo := fmt.Sprintf("error: %s no such file or directory", prefix)
	return errors.New(errInfo)
	}
	return nil
	}

	func getPrefix(file string) string {
	// tar strips the leading '/' if it's there, so we will too
	return strings.TrimLeft(file, "/")
	}

	func (o CopyOptions) execute(options exec.ExecOptions) error {
	if len(options.Namespace) == 0 {
	options.Namespace = o.Namespace
	}

	if len(o.Container) > 0 {
	options.ContainerName = o.Container
	}

	options.Config = o.ClientConfig
	options.PodClient = o.Clientset.Core()

	if err := options.Validate(); err != nil {
	return err
	}

	if err := options.Run(); err != nil {
	return err
	}
	return nil
	}

	// dirExists checks if a path exists and is a directory.
	func dirExists(path string) (bool, error) {
	fi, err := os.Stat(path)
	if err == nil && fi.IsDir() {
	return true, nil
	}
	if os.IsNotExist(err) {
	return false, nil
	}
	return false, err
	}