// Import imports an image, getting the archived layer data either from
// inConfig (if src is "-"), or from a URI specified in src. Progress output is
// written to outStream. Repository and tag names can optionally be given in
// the repo and tag arguments, respectively.
func (s *TagStore) Import(src string, repo string, tag string, inConfig io.ReadCloser, outStream io.Writer, containerConfig *runconfig.Config) error {
	var (
		sf      = streamformatter.NewJSONStreamFormatter()
		archive io.ReadCloser
		resp    *http.Response
	)

	if src == "-" {
		archive = inConfig
	} else {
		inConfig.Close()
		u, err := url.Parse(src)
		if err != nil {
			return err
		}
		if u.Scheme == "" {
			u.Scheme = "http"
			u.Host = src
			u.Path = ""
		}
		outStream.Write(sf.FormatStatus("", "Downloading from %s", u))
		resp, err = httputils.Download(u.String())
		if err != nil {
			return err
		}
		progressReader := progressreader.New(progressreader.Config{
			In:        resp.Body,
			Out:       outStream,
			Formatter: sf,
			Size:      resp.ContentLength,
			NewLines:  true,
			ID:        "",
			Action:    "Importing",
		})
		archive = progressReader
	}

	defer archive.Close()
	img, err := s.graph.Create(archive, "", "", "Imported from "+src, "", nil, containerConfig)
	if err != nil {
		return err
	}
	// Optionally register the image at REPO/TAG
	if repo != "" {
		if err := s.Tag(repo, tag, img.ID, true); err != nil {
			return err
		}
	}
	outStream.Write(sf.FormatStatus("", img.ID))
	logID := img.ID
	if tag != "" {
		logID = utils.ImageReference(logID, tag)
	}

	s.eventsService.Log("import", logID, "")
	return nil
}

// getContextFromURL uses a remote URL as context for a `docker build`. The
// remote resource is downloaded as either a Dockerfile or a tar archive.
// Returns the tar archive used for the context and a path of the
// dockerfile inside the tar.
func getContextFromURL(out io.Writer, remoteURL, dockerfileName string) (io.ReadCloser, string, error) {
	response, err := httputils.Download(remoteURL)
	if err != nil {
		return nil, "", fmt.Errorf("unable to download remote context %s: %v", remoteURL, err)
	}
	progressOutput := streamformatter.NewStreamFormatter().NewProgressOutput(out, true)

	// Pass the response body through a progress reader.
	progReader := progress.NewProgressReader(response.Body, progressOutput, response.ContentLength, "", fmt.Sprintf("Downloading build context from remote url: %s", remoteURL))

	return getContextFromReader(ioutils.NewReadCloserWrapper(progReader, func() error { return response.Body.Close() }), dockerfileName)
}

// getContextFromURL uses a remote URL as context for a `docker build`. The
// remote resource is downloaded as either a Dockerfile or a context tar
// archive and stored in a temporary directory used as the context directory.
// Returns the absolute path to the temporary context directory, the relative
// path of the dockerfile in that context directory, and a non-nil error on
// success.
func getContextFromURL(out io.Writer, remoteURL, dockerfileName string) (absContextDir, relDockerfile string, err error) {
	response, err := httputils.Download(remoteURL)
	if err != nil {
		return "", "", fmt.Errorf("unable to download remote context %s: %v", remoteURL, err)
	}
	defer response.Body.Close()

	// Pass the response body through a progress reader.
	progReader := &progressreader.Config{
		In:        response.Body,
		Out:       out,
		Formatter: streamformatter.NewStreamFormatter(),
		Size:      response.ContentLength,
		NewLines:  true,
		ID:        "",
		Action:    fmt.Sprintf("Downloading build context from remote url: %s", remoteURL),
	}

	return getContextFromReader(progReader, dockerfileName)
}

// MakeRemoteContext downloads a context from remoteURL and returns it.
//
// If contentTypeHandlers is non-nil, then the Content-Type header is read along with a maximum of
// maxPreambleLength bytes from the body to help detecting the MIME type.
// Look at acceptableRemoteMIME for more details.
//
// If a match is found, then the body is sent to the contentType handler and a (potentially compressed) tar stream is expected
// to be returned. If no match is found, it is assumed the body is a tar stream (compressed or not).
// In either case, an (assumed) tar stream is passed to MakeTarSumContext whose result is returned.
func MakeRemoteContext(remoteURL string, contentTypeHandlers map[string]func(io.ReadCloser) (io.ReadCloser, error)) (ModifiableContext, error) {
	f, err := httputils.Download(remoteURL)
	if err != nil {
		return nil, fmt.Errorf("error downloading remote context %s: %v", remoteURL, err)
	}
	defer f.Body.Close()

	var contextReader io.ReadCloser
	if contentTypeHandlers != nil {
		contentType := f.Header.Get("Content-Type")
		clen := f.ContentLength

		contentType, contextReader, err = inspectResponse(contentType, f.Body, clen)
		if err != nil {
			return nil, fmt.Errorf("error detecting content type for remote %s: %v", remoteURL, err)
		}
		defer contextReader.Close()

		// This loop tries to find a content-type handler for the detected content-type.
		// If it could not find one from the caller-supplied map, it tries the empty content-type `""`
		// which is interpreted as a fallback handler (usually used for raw tar contexts).
		for _, ct := range []string{contentType, ""} {
			if fn, ok := contentTypeHandlers[ct]; ok {
				defer contextReader.Close()
				if contextReader, err = fn(contextReader); err != nil {
					return nil, err
				}
				break
			}
		}
	}

	// Pass through - this is a pre-packaged context, presumably
	// with a Dockerfile with the right name inside it.
	return MakeTarSumContext(contextReader)
}

// ImportImage imports an image, getting the archived layer data either from
// inConfig (if src is "-"), or from a URI specified in src. Progress output is
// written to outStream. Repository and tag names can optionally be given in
// the repo and tag arguments, respectively.
func (daemon *Daemon) ImportImage(src string, repository, tag string, msg string, inConfig io.ReadCloser, outStream io.Writer, changes []string) error {
	var (
		sf     = streamformatter.NewJSONStreamFormatter()
		rc     io.ReadCloser
		resp   *http.Response
		newRef reference.Named
	)

	if repository != "" {
		var err error
		newRef, err = reference.ParseNamed(repository)
		if err != nil {
			return err
		}

		if _, isCanonical := newRef.(reference.Canonical); isCanonical {
			return errors.New("cannot import digest reference")
		}

		if tag != "" {
			newRef, err = reference.WithTag(newRef, tag)
			if err != nil {
				return err
			}
		}
	}

	config, err := dockerfile.BuildFromConfig(&container.Config{}, changes)
	if err != nil {
		return err
	}
	if src == "-" {
		rc = inConfig
	} else {
		inConfig.Close()
		u, err := url.Parse(src)
		if err != nil {
			return err
		}
		if u.Scheme == "" {
			u.Scheme = "http"
			u.Host = src
			u.Path = ""
		}
		outStream.Write(sf.FormatStatus("", "Downloading from %s", u))
		resp, err = httputils.Download(u.String())
		if err != nil {
			return err
		}
		progressOutput := sf.NewProgressOutput(outStream, true)
		rc = progress.NewProgressReader(resp.Body, progressOutput, resp.ContentLength, "", "Importing")
	}

	defer rc.Close()
	if len(msg) == 0 {
		msg = "Imported from " + src
	}

	inflatedLayerData, err := archive.DecompressStream(rc)
	if err != nil {
		return err
	}
	// TODO: support windows baselayer?
	l, err := daemon.layerStore.Register(inflatedLayerData, "")
	if err != nil {
		return err
	}
	defer layer.ReleaseAndLog(daemon.layerStore, l)

	created := time.Now().UTC()
	imgConfig, err := json.Marshal(&image.Image{
		V1Image: image.V1Image{
			DockerVersion: dockerversion.Version,
			Config:        config,
			Architecture:  runtime.GOARCH,
			OS:            runtime.GOOS,
			Created:       created,
			Comment:       msg,
		},
		RootFS: &image.RootFS{
			Type:    "layers",
			DiffIDs: []layer.DiffID{l.DiffID()},
		},
		History: []image.History{{
			Created: created,
			Comment: msg,
		}},
	})
	if err != nil {
		return err
	}

	id, err := daemon.imageStore.Create(imgConfig)
	if err != nil {
		return err
	}
//.........这里部分代码省略.........

func (b *Builder) download(srcURL string) (fi builder.FileInfo, err error) {
	// get filename from URL
	u, err := url.Parse(srcURL)
	if err != nil {
		return
	}
	path := filepath.FromSlash(u.Path) // Ensure in platform semantics
	if strings.HasSuffix(path, string(os.PathSeparator)) {
		path = path[:len(path)-1]
	}
	parts := strings.Split(path, string(os.PathSeparator))
	filename := parts[len(parts)-1]
	if filename == "" {
		err = fmt.Errorf("cannot determine filename from url: %s", u)
		return
	}

	// Initiate the download
	resp, err := httputils.Download(srcURL)
	if err != nil {
		return
	}

	// Prepare file in a tmp dir
	tmpDir, err := ioutils.TempDir("", "docker-remote")
	if err != nil {
		return
	}
	defer func() {
		if err != nil {
			os.RemoveAll(tmpDir)
		}
	}()
	tmpFileName := filepath.Join(tmpDir, filename)
	tmpFile, err := os.OpenFile(tmpFileName, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0600)
	if err != nil {
		return
	}

	stdoutFormatter := b.Stdout.(*streamformatter.StdoutFormatter)
	progressOutput := stdoutFormatter.StreamFormatter.NewProgressOutput(stdoutFormatter.Writer, true)
	progressReader := progress.NewProgressReader(resp.Body, progressOutput, resp.ContentLength, "", "Downloading")
	// Download and dump result to tmp file
	if _, err = io.Copy(tmpFile, progressReader); err != nil {
		tmpFile.Close()
		return
	}
	fmt.Fprintln(b.Stdout)
	// ignoring error because the file was already opened successfully
	tmpFileSt, err := tmpFile.Stat()
	if err != nil {
		return
	}
	tmpFile.Close()

	// Set the mtime to the Last-Modified header value if present
	// Otherwise just remove atime and mtime
	mTime := time.Time{}

	lastMod := resp.Header.Get("Last-Modified")
	if lastMod != "" {
		// If we can't parse it then just let it default to 'zero'
		// otherwise use the parsed time value
		if parsedMTime, err := http.ParseTime(lastMod); err == nil {
			mTime = parsedMTime
		}
	}

	if err = system.Chtimes(tmpFileName, mTime, mTime); err != nil {
		return
	}

	// Calc the checksum, even if we're using the cache
	r, err := archive.Tar(tmpFileName, archive.Uncompressed)
	if err != nil {
		return
	}
	tarSum, err := tarsum.NewTarSum(r, true, tarsum.Version1)
	if err != nil {
		return
	}
	if _, err = io.Copy(ioutil.Discard, tarSum); err != nil {
		return
	}
	hash := tarSum.Sum(nil)
	r.Close()
	return &builder.HashedFileInfo{FileInfo: builder.PathFileInfo{FileInfo: tmpFileSt, FilePath: tmpFileName}, FileHash: hash}, nil
}

func calcCopyInfo(b *Builder, cmdName string, cInfos *[]*copyInfo, origPath string, destPath string, allowRemote bool, allowDecompression bool, allowWildcards bool) error {

	if origPath != "" && origPath[0] == '/' && len(origPath) > 1 {
		origPath = origPath[1:]
	}
	origPath = strings.TrimPrefix(origPath, "./")

	// Twiddle the destPath when its a relative path - meaning, make it
	// relative to the WORKINGDIR
	if !filepath.IsAbs(destPath) {
		hasSlash := strings.HasSuffix(destPath, "/")
		destPath = filepath.Join("/", b.Config.WorkingDir, destPath)

		// Make sure we preserve any trailing slash
		if hasSlash {
			destPath += "/"
		}
	}

	// In the remote/URL case, download it and gen its hashcode
	if urlutil.IsURL(origPath) {
		if !allowRemote {
			return fmt.Errorf("Source can't be a URL for %s", cmdName)
		}

		ci := copyInfo{}
		ci.origPath = origPath
		ci.hash = origPath // default to this but can change
		ci.destPath = destPath
		ci.decompress = false
		*cInfos = append(*cInfos, &ci)

		// Initiate the download
		resp, err := httputils.Download(ci.origPath)
		if err != nil {
			return err
		}

		// Create a tmp dir
		tmpDirName, err := ioutil.TempDir(b.contextPath, "docker-remote")
		if err != nil {
			return err
		}
		ci.tmpDir = tmpDirName

		// Create a tmp file within our tmp dir
		tmpFileName := filepath.Join(tmpDirName, "tmp")
		tmpFile, err := os.OpenFile(tmpFileName, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0600)
		if err != nil {
			return err
		}

		// Download and dump result to tmp file
		if _, err := io.Copy(tmpFile, progressreader.New(progressreader.Config{
			In:        resp.Body,
			Out:       b.OutOld,
			Formatter: b.StreamFormatter,
			Size:      int(resp.ContentLength),
			NewLines:  true,
			ID:        "",
			Action:    "Downloading",
		})); err != nil {
			tmpFile.Close()
			return err
		}
		fmt.Fprintf(b.OutStream, "\n")
		tmpFile.Close()

		// Set the mtime to the Last-Modified header value if present
		// Otherwise just remove atime and mtime
		times := make([]syscall.Timespec, 2)

		lastMod := resp.Header.Get("Last-Modified")
		if lastMod != "" {
			mTime, err := http.ParseTime(lastMod)
			// If we can't parse it then just let it default to 'zero'
			// otherwise use the parsed time value
			if err == nil {
				times[1] = syscall.NsecToTimespec(mTime.UnixNano())
			}
		}

		if err := system.UtimesNano(tmpFileName, times); err != nil {
			return err
		}

		ci.origPath = filepath.Join(filepath.Base(tmpDirName), filepath.Base(tmpFileName))

		// If the destination is a directory, figure out the filename.
		if strings.HasSuffix(ci.destPath, "/") {
			u, err := url.Parse(origPath)
			if err != nil {
				return err
			}
			path := u.Path
			if strings.HasSuffix(path, "/") {
				path = path[:len(path)-1]
			}
			parts := strings.Split(path, "/")
			filename := parts[len(parts)-1]
//.........这里部分代码省略.........

// Build is the main interface of the package, it gathers the Builder
// struct and calls builder.Run() to do all the real build job.
func Build(d *daemon.Daemon, buildConfig *Config) error {
	var (
		repoName string
		tag      string
		context  io.ReadCloser
	)
	sf := streamformatter.NewJSONStreamFormatter()

	repoName, tag = parsers.ParseRepositoryTag(buildConfig.RepoName)
	if repoName != "" {
		if err := registry.ValidateRepositoryName(repoName); err != nil {
			return err
		}
		if len(tag) > 0 {
			if err := tags.ValidateTagName(tag); err != nil {
				return err
			}
		}
	}

	if buildConfig.RemoteURL == "" {
		context = ioutil.NopCloser(buildConfig.Context)
	} else if urlutil.IsGitURL(buildConfig.RemoteURL) {
		root, err := utils.GitClone(buildConfig.RemoteURL)
		if err != nil {
			return err
		}
		defer os.RemoveAll(root)

		c, err := archive.Tar(root, archive.Uncompressed)
		if err != nil {
			return err
		}
		context = c
	} else if urlutil.IsURL(buildConfig.RemoteURL) {
		f, err := httputils.Download(buildConfig.RemoteURL)
		if err != nil {
			return fmt.Errorf("Error downloading remote context %s: %v", buildConfig.RemoteURL, err)
		}
		defer f.Body.Close()
		ct := f.Header.Get("Content-Type")
		clen := int(f.ContentLength)
		contentType, bodyReader, err := inspectResponse(ct, f.Body, clen)

		defer bodyReader.Close()

		if err != nil {
			return fmt.Errorf("Error detecting content type for remote %s: %v", buildConfig.RemoteURL, err)
		}
		if contentType == httputils.MimeTypes.TextPlain {
			dockerFile, err := ioutil.ReadAll(bodyReader)
			if err != nil {
				return err
			}

			// When we're downloading just a Dockerfile put it in
			// the default name - don't allow the client to move/specify it
			buildConfig.DockerfileName = api.DefaultDockerfileName

			c, err := archive.Generate(buildConfig.DockerfileName, string(dockerFile))
			if err != nil {
				return err
			}
			context = c
		} else {
			// Pass through - this is a pre-packaged context, presumably
			// with a Dockerfile with the right name inside it.
			prCfg := progressreader.Config{
				In:        bodyReader,
				Out:       buildConfig.Stdout,
				Formatter: sf,
				Size:      clen,
				NewLines:  true,
				ID:        "Downloading context",
				Action:    buildConfig.RemoteURL,
			}
			context = progressreader.New(prCfg)
		}
	}

	defer context.Close()

	builder := &builder{
		Daemon: d,
		OutStream: &streamformatter.StdoutFormater{
			Writer:          buildConfig.Stdout,
			StreamFormatter: sf,
		},
		ErrStream: &streamformatter.StderrFormater{
			Writer:          buildConfig.Stdout,
			StreamFormatter: sf,
		},
		Verbose:         !buildConfig.SuppressOutput,
		UtilizeCache:    !buildConfig.NoCache,
		Remove:          buildConfig.Remove,
		ForceRemove:     buildConfig.ForceRemove,
		Pull:            buildConfig.Pull,
		OutOld:          buildConfig.Stdout,
//.........这里部分代码省略.........

func Build(d *daemon.Daemon, buildConfig *Config) error {
	var (
		repoName string
		tag      string
		context  io.ReadCloser
	)

	repoName, tag = parsers.ParseRepositoryTag(buildConfig.RepoName)
	if repoName != "" {
		if err := registry.ValidateRepositoryName(repoName); err != nil {
			return err
		}
		if len(tag) > 0 {
			if err := tags.ValidateTagName(tag); err != nil {
				return err
			}
		}
	}

	if buildConfig.RemoteURL == "" {
		context = ioutil.NopCloser(buildConfig.Context)
	} else if urlutil.IsGitURL(buildConfig.RemoteURL) {
		root, err := utils.GitClone(buildConfig.RemoteURL)
		if err != nil {
			return err
		}
		defer os.RemoveAll(root)

		c, err := archive.Tar(root, archive.Uncompressed)
		if err != nil {
			return err
		}
		context = c
	} else if urlutil.IsURL(buildConfig.RemoteURL) {
		f, err := httputils.Download(buildConfig.RemoteURL)
		if err != nil {
			return err
		}
		defer f.Body.Close()
		dockerFile, err := ioutil.ReadAll(f.Body)
		if err != nil {
			return err
		}

		// When we're downloading just a Dockerfile put it in
		// the default name - don't allow the client to move/specify it
		buildConfig.DockerfileName = api.DefaultDockerfileName

		c, err := archive.Generate(buildConfig.DockerfileName, string(dockerFile))
		if err != nil {
			return err
		}
		context = c
	}
	defer context.Close()

	sf := streamformatter.NewJSONStreamFormatter()

	builder := &Builder{
		Daemon: d,
		OutStream: &streamformatter.StdoutFormater{
			Writer:          buildConfig.Stdout,
			StreamFormatter: sf,
		},
		ErrStream: &streamformatter.StderrFormater{
			Writer:          buildConfig.Stdout,
			StreamFormatter: sf,
		},
		Verbose:         !buildConfig.SuppressOutput,
		UtilizeCache:    !buildConfig.NoCache,
		Remove:          buildConfig.Remove,
		ForceRemove:     buildConfig.ForceRemove,
		Pull:            buildConfig.Pull,
		OutOld:          buildConfig.Stdout,
		StreamFormatter: sf,
		AuthConfig:      buildConfig.AuthConfig,
		ConfigFile:      buildConfig.ConfigFile,
		dockerfileName:  buildConfig.DockerfileName,
		cpuShares:       buildConfig.CpuShares,
		cpuPeriod:       buildConfig.CpuPeriod,
		cpuQuota:        buildConfig.CpuQuota,
		cpuSetCpus:      buildConfig.CpuSetCpus,
		cpuSetMems:      buildConfig.CpuSetMems,
		cgroupParent:    buildConfig.CgroupParent,
		memory:          buildConfig.Memory,
		memorySwap:      buildConfig.MemorySwap,
		cancelled:       buildConfig.WaitCancelled(),
	}

	id, err := builder.Run(context)
	if err != nil {
		return err
	}

	if repoName != "" {
		return d.Repositories().Tag(repoName, tag, id, true)
	}
	return nil
}

// ImportImage imports an image, getting the archived layer data either from
// inConfig (if src is "-"), or from a URI specified in src. Progress output is
// written to outStream. Repository and tag names can optionally be given in
// the repo and tag arguments, respectively.
func (daemon *Daemon) ImportImage(src string, newRef reference.Named, msg string, inConfig io.ReadCloser, outStream io.Writer, config *runconfig.Config) error {
	var (
		sf      = streamformatter.NewJSONStreamFormatter()
		archive io.ReadCloser
		resp    *http.Response
	)

	if src == "-" {
		archive = inConfig
	} else {
		inConfig.Close()
		u, err := url.Parse(src)
		if err != nil {
			return err
		}
		if u.Scheme == "" {
			u.Scheme = "http"
			u.Host = src
			u.Path = ""
		}
		outStream.Write(sf.FormatStatus("", "Downloading from %s", u))
		resp, err = httputils.Download(u.String())
		if err != nil {
			return err
		}
		progressOutput := sf.NewProgressOutput(outStream, true)
		archive = progress.NewProgressReader(resp.Body, progressOutput, resp.ContentLength, "", "Importing")
	}

	defer archive.Close()
	if len(msg) == 0 {
		msg = "Imported from " + src
	}
	// TODO: support windows baselayer?
	l, err := daemon.layerStore.Register(archive, "")
	if err != nil {
		return err
	}
	defer layer.ReleaseAndLog(daemon.layerStore, l)

	created := time.Now().UTC()
	imgConfig, err := json.Marshal(&image.Image{
		V1Image: image.V1Image{
			DockerVersion: dockerversion.Version,
			Config:        config,
			Architecture:  runtime.GOARCH,
			OS:            runtime.GOOS,
			Created:       created,
			Comment:       msg,
		},
		RootFS: &image.RootFS{
			Type:    "layers",
			DiffIDs: []layer.DiffID{l.DiffID()},
		},
		History: []image.History{{
			Created: created,
			Comment: msg,
		}},
	})
	if err != nil {
		return err
	}

	id, err := daemon.imageStore.Create(imgConfig)
	if err != nil {
		return err
	}

	// FIXME: connect with commit code and call refstore directly
	if newRef != nil {
		if err := daemon.TagImage(newRef, id.String()); err != nil {
			return err
		}
	}

	outStream.Write(sf.FormatStatus("", id.String()))
	daemon.EventsService.Log("import", id.String(), "")
	return nil
}

func (b *BuilderJob) CmdBuild(job *engine.Job) error {
	if len(job.Args) != 0 {
		return fmt.Errorf("Usage: %s\n", job.Name)
	}
	var (
		dockerfileName = job.Getenv("dockerfile")
		remoteURL      = job.Getenv("remote")
		repoName       = job.Getenv("t")
		suppressOutput = job.GetenvBool("q")
		noCache        = job.GetenvBool("nocache")
		rm             = job.GetenvBool("rm")
		forceRm        = job.GetenvBool("forcerm")
		pull           = job.GetenvBool("pull")
		memory         = job.GetenvInt64("memory")
		memorySwap     = job.GetenvInt64("memswap")
		cpuShares      = job.GetenvInt64("cpushares")
		cpuSetCpus     = job.Getenv("cpusetcpus")
		cpuSetMems     = job.Getenv("cpusetmems")
		authConfig     = &registry.AuthConfig{}
		configFile     = &registry.ConfigFile{}
		tag            string
		context        io.ReadCloser
	)

	job.GetenvJson("authConfig", authConfig)
	job.GetenvJson("configFile", configFile)

	repoName, tag = parsers.ParseRepositoryTag(repoName)
	if repoName != "" {
		if err := registry.ValidateRepositoryName(repoName); err != nil {
			return err
		}
		if len(tag) > 0 {
			if err := graph.ValidateTagName(tag); err != nil {
				return err
			}
		}
	}

	if remoteURL == "" {
		context = ioutil.NopCloser(job.Stdin)
	} else if urlutil.IsGitURL(remoteURL) {
		if !urlutil.IsGitTransport(remoteURL) {
			remoteURL = "https://" + remoteURL
		}
		root, err := ioutil.TempDir("", "docker-build-git")
		if err != nil {
			return err
		}
		defer os.RemoveAll(root)

		if output, err := exec.Command("git", "clone", "--recursive", remoteURL, root).CombinedOutput(); err != nil {
			return fmt.Errorf("Error trying to use git: %s (%s)", err, output)
		}

		c, err := archive.Tar(root, archive.Uncompressed)
		if err != nil {
			return err
		}
		context = c
	} else if urlutil.IsURL(remoteURL) {
		f, err := httputils.Download(remoteURL)
		if err != nil {
			return err
		}
		defer f.Body.Close()
		dockerFile, err := ioutil.ReadAll(f.Body)
		if err != nil {
			return err
		}

		// When we're downloading just a Dockerfile put it in
		// the default name - don't allow the client to move/specify it
		dockerfileName = api.DefaultDockerfileName

		c, err := archive.Generate(dockerfileName, string(dockerFile))
		if err != nil {
			return err
		}
		context = c
	}
	defer context.Close()

	sf := streamformatter.NewStreamFormatter(job.GetenvBool("json"))

	builder := &Builder{
		Daemon: b.Daemon,
		Engine: b.Engine,
		OutStream: &streamformatter.StdoutFormater{
			Writer:          job.Stdout,
			StreamFormatter: sf,
		},
		ErrStream: &streamformatter.StderrFormater{
			Writer:          job.Stdout,
			StreamFormatter: sf,
		},
		Verbose:         !suppressOutput,
		UtilizeCache:    !noCache,
		Remove:          rm,
		ForceRemove:     forceRm,
//.........这里部分代码省略.........

func (s *TagStore) CmdImport(job *engine.Job) error {
	if n := len(job.Args); n != 2 && n != 3 {
		return fmt.Errorf("Usage: %s SRC REPO [TAG]", job.Name)
	}
	var (
		src          = job.Args[0]
		repo         = job.Args[1]
		tag          string
		sf           = streamformatter.NewStreamFormatter(job.GetenvBool("json"))
		archive      archive.ArchiveReader
		resp         *http.Response
		stdoutBuffer = bytes.NewBuffer(nil)
		newConfig    runconfig.Config
	)
	if len(job.Args) > 2 {
		tag = job.Args[2]
	}

	if src == "-" {
		archive = job.Stdin
	} else {
		u, err := url.Parse(src)
		if err != nil {
			return err
		}
		if u.Scheme == "" {
			u.Scheme = "http"
			u.Host = src
			u.Path = ""
		}
		job.Stdout.Write(sf.FormatStatus("", "Downloading from %s", u))
		resp, err = httputils.Download(u.String())
		if err != nil {
			return err
		}
		progressReader := progressreader.New(progressreader.Config{
			In:        resp.Body,
			Out:       job.Stdout,
			Formatter: sf,
			Size:      int(resp.ContentLength),
			NewLines:  true,
			ID:        "",
			Action:    "Importing",
		})
		defer progressReader.Close()
		archive = progressReader
	}

	buildConfigJob := job.Eng.Job("build_config")
	buildConfigJob.Stdout.Add(stdoutBuffer)
	buildConfigJob.Setenv("changes", job.Getenv("changes"))
	// FIXME this should be remove when we remove deprecated config param
	buildConfigJob.Setenv("config", job.Getenv("config"))

	if err := buildConfigJob.Run(); err != nil {
		return err
	}
	if err := json.NewDecoder(stdoutBuffer).Decode(&newConfig); err != nil {
		return err
	}

	img, err := s.graph.Create(archive, "", "", "Imported from "+src, "", nil, &newConfig)
	if err != nil {
		return err
	}
	// Optionally register the image at REPO/TAG
	if repo != "" {
		if err := s.Set(repo, tag, img.ID, true); err != nil {
			return err
		}
	}
	job.Stdout.Write(sf.FormatStatus("", img.ID))
	logID := img.ID
	if tag != "" {
		logID = utils.ImageReference(logID, tag)
	}

	s.eventsService.Log("import", logID, "")
	return nil
}