func checkForPorts(repo *app.SourceRepository) []string {
	info := repo.Info()
	if info == nil || info.Dockerfile == nil {
		return nil
	}
	node := info.Dockerfile.AST()
	return dockerfile.LastExposedPorts(node)
}

func exposedPortsAreNumeric(node *dockerfileparser.Node) error {
	for _, port := range dockerfileutil.LastExposedPorts(node) {
		if _, err := strconv.ParseInt(port, 10, 32); err != nil {
			return fmt.Errorf("could not parse %q: must be numeric", port)
		}
	}
	return nil
}

// FromDockerfile generates an ImageRef from a given name, directory, and context path.
// The directory and context path will be joined and the resulting path should be a
// Dockerfile from where the image's ports will be extracted.
func (g *imageRefGenerator) FromDockerfile(name string, dir string, context string) (*ImageRef, error) {
	// Look for Dockerfile in repository
	file, err := os.Open(filepath.Join(dir, context, "Dockerfile"))
	if err != nil {
		return nil, err
	}

	node, err := parser.Parse(file)
	if err != nil {
		return nil, err
	}
	ports := dockerfile.LastExposedPorts(node)

	return g.FromNameAndPorts(name, ports)
}

// buildPipelines converts a set of resolved, valid references into pipelines.
func (c *AppConfig) buildPipelines(components app.ComponentReferences, environment app.Environment) (app.PipelineGroup, error) {
	pipelines := app.PipelineGroup{}
	names := map[string]int{}
	for _, group := range components.Group() {
		glog.V(4).Infof("found group: %#v", group)
		common := app.PipelineGroup{}
		for _, ref := range group {
			var pipeline *app.Pipeline
			var name string
			if ref.Input().ExpectToBuild {
				glog.V(4).Infof("will use %q as the base image for a source build of %q", ref, ref.Input().Uses)
				input, err := app.InputImageFromMatch(ref.Input().ResolvedMatch)
				if err != nil {
					return nil, fmt.Errorf("can't build %q: %v", ref.Input(), err)
				}
				if !input.AsImageStream {
					glog.Warningf("Could not find an image stream match for %q. Make sure that a Docker image with that tag is available on the node for the build to succeed.", ref.Input().ResolvedMatch.Value)
				}
				strategy, source, err := app.StrategyAndSourceForRepository(ref.Input().Uses, input)
				if err != nil {
					return nil, fmt.Errorf("can't build %q: %v", ref.Input(), err)
				}

				// Override resource names from the cli
				name = c.Name
				if len(name) == 0 {
					var ok bool
					name, ok = (app.NameSuggestions{source, input}).SuggestName()
					if !ok {
						return nil, fmt.Errorf("can't suggest a valid name, please specify a name with --name")
					}
				}
				name, err = ensureValidUniqueName(names, name)
				source.Name = name
				if err != nil {
					return nil, err
				}

				// Append any exposed ports from Dockerfile to input image
				if ref.Input().Uses.IsDockerBuild() && ref.Input().Uses.Info() != nil {
					node := ref.Input().Uses.Info().Dockerfile.AST()
					ports := dockerfileutil.LastExposedPorts(node)
					if len(ports) > 0 {
						if input.Info == nil {
							input.Info = &imageapi.DockerImage{
								Config: &imageapi.DockerConfig{},
							}
						}
						input.Info.Config.ExposedPorts = map[string]struct{}{}
						for _, p := range ports {
							input.Info.Config.ExposedPorts[p] = struct{}{}
						}
					}
				}
				if pipeline, err = app.NewBuildPipeline(ref.Input().String(), input, c.OutputDocker, strategy, c.GetBuildEnvironment(environment), source); err != nil {
					return nil, fmt.Errorf("can't build %q: %v", ref.Input(), err)
				}

			} else {
				glog.V(4).Infof("will include %q", ref)
				input, err := app.InputImageFromMatch(ref.Input().ResolvedMatch)
				if err != nil {
					return nil, fmt.Errorf("can't include %q: %v", ref.Input(), err)
				}
				name = c.Name
				if len(name) == 0 {
					var ok bool
					name, ok = input.SuggestName()
					if !ok {
						return nil, fmt.Errorf("can't suggest a valid name, please specify a name with --name")
					}
				}
				name, err = ensureValidUniqueName(names, name)
				if err != nil {
					return nil, err
				}
				input.ObjectName = name
				if pipeline, err = app.NewImagePipeline(ref.Input().String(), input); err != nil {
					return nil, fmt.Errorf("can't include %q: %v", ref.Input(), err)
				}
			}

			if err := pipeline.NeedsDeployment(environment, c.Labels, name); err != nil {
				return nil, fmt.Errorf("can't set up a deployment for %q: %v", ref.Input(), err)
			}
			common = append(common, pipeline)
		}

		if err := common.Reduce(); err != nil {
			return nil, fmt.Errorf("can't create a pipeline from %s: %v", common, err)
		}
		pipelines = append(pipelines, common...)
	}
	return pipelines, nil
}

// NewBuildPipeline creates a new pipeline with components that are expected to
// be built.
func (pb *pipelineBuilder) NewBuildPipeline(from string, input *ImageRef, sourceRepository *SourceRepository) (*Pipeline, error) {
	strategy, source, err := StrategyAndSourceForRepository(sourceRepository, input)
	if err != nil {
		return nil, fmt.Errorf("can't build %q: %v", from, err)
	}

	var name string
	output := &ImageRef{
		OutputImage:   true,
		AsImageStream: !pb.outputDocker,
	}
	if len(pb.to) > 0 {
		outputImageRef, err := image.ParseDockerImageReference(pb.to)
		if err != nil {
			return nil, err
		}
		output.Reference = outputImageRef
		name, err = pb.nameGenerator.Generate(NameSuggestions{source, output, input})
		if err != nil {
			return nil, err
		}
	} else {
		name, err = pb.nameGenerator.Generate(NameSuggestions{source, input})
		if err != nil {
			return nil, err
		}
		output.Reference = image.DockerImageReference{
			Name: name,
			Tag:  image.DefaultImageTag,
		}
	}
	source.Name = name

	// Append any exposed ports from Dockerfile to input image
	if sourceRepository.IsDockerBuild() && sourceRepository.Info() != nil {
		node := sourceRepository.Info().Dockerfile.AST()
		ports := dockerfile.LastExposedPorts(node)
		if len(ports) > 0 {
			if input.Info == nil {
				input.Info = &image.DockerImage{
					Config: &image.DockerConfig{},
				}
			}
			input.Info.Config.ExposedPorts = map[string]struct{}{}
			for _, p := range ports {
				input.Info.Config.ExposedPorts[p] = struct{}{}
			}
		}
	}

	if input != nil {
		// TODO: assumes that build doesn't change the image metadata. In the future
		// we could get away with deferred generation possibly.
		output.Info = input.Info
	}

	build := &BuildRef{
		Source:   source,
		Input:    input,
		Strategy: strategy,
		Output:   output,
		Env:      pb.environment,
	}

	return &Pipeline{
		Name:       name,
		From:       from,
		InputImage: input,
		Image:      output,
		Build:      build,
	}, nil
}

// NewBuildPipeline creates a new pipeline with components that are expected to
// be built.
func (pb *pipelineBuilder) NewBuildPipeline(from string, resolvedMatch *ComponentMatch, sourceRepository *SourceRepository) (*Pipeline, error) {
	input, err := InputImageFromMatch(resolvedMatch)
	if err != nil {
		return nil, fmt.Errorf("can't build %q: %v", from, err)
	}
	if !input.AsImageStream {
		msg := "Could not find an image stream match for %q. Make sure that a Docker image with that tag is available on the node for the build to succeed."
		glog.Warningf(msg, resolvedMatch.Value)
	}

	strategy, source, err := StrategyAndSourceForRepository(sourceRepository, input)
	if err != nil {
		return nil, fmt.Errorf("can't build %q: %v", from, err)
	}

	name, err := pb.nameGenerator.Generate(NameSuggestions{source, input})
	if err != nil {
		return nil, err
	}
	source.Name = name

	// Append any exposed ports from Dockerfile to input image
	if sourceRepository.IsDockerBuild() && sourceRepository.Info() != nil {
		node := sourceRepository.Info().Dockerfile.AST()
		ports := dockerfile.LastExposedPorts(node)
		if len(ports) > 0 {
			if input.Info == nil {
				input.Info = &image.DockerImage{
					Config: &image.DockerConfig{},
				}
			}
			input.Info.Config.ExposedPorts = map[string]struct{}{}
			for _, p := range ports {
				input.Info.Config.ExposedPorts[p] = struct{}{}
			}
		}
	}

	output := &ImageRef{
		Reference: image.DockerImageReference{
			Name: name,
			Tag:  image.DefaultImageTag,
		},
		OutputImage:   true,
		AsImageStream: !pb.outputDocker,
	}
	if input != nil {
		// TODO: assumes that build doesn't change the image metadata. In the future
		// we could get away with deferred generation possibly.
		output.Info = input.Info
	}

	build := &BuildRef{
		Source:   source,
		Input:    input,
		Strategy: strategy,
		Output:   output,
		Env:      pb.environment,
	}

	return &Pipeline{
		Name:       name,
		From:       from,
		InputImage: input,
		Image:      output,
		Build:      build,
	}, nil
}

//.........这里部分代码省略.........
	buildPath := appJSON.Repository
	if len(buildPath) == 0 && len(g.LocalPath) > 0 {
		buildPath = g.LocalPath
	}
	if len(buildPath) == 0 {
		return nil, fmt.Errorf("app.json did not contain a repository URL and no local path was specified")
	}

	repo, err := app.NewSourceRepository(buildPath, generate.StrategyDocker)
	if err != nil {
		return nil, err
	}

	var ports []string

	var pipelines app.PipelineGroup
	baseImage := g.BaseImage
	if len(baseImage) == 0 {
		baseImage = appJSON.Image
	}
	if len(baseImage) == 0 {
		return nil, fmt.Errorf("Docker image required: provide an --image flag or 'image' key in app.json")
	}

	fakeDockerfile := heredoc.Docf(`
      # Generated from app.json
      FROM %s
    `, baseImage)

	dockerfilePath := filepath.Join(buildPath, "Dockerfile")
	if df, err := app.NewDockerfileFromFile(dockerfilePath); err == nil {
		repo.Info().Dockerfile = df
		repo.Info().Path = dockerfilePath
		ports = dockerfile.LastExposedPorts(df.AST())
	}
	// TODO: look for procfile for more info?

	image, err := imageGen.FromNameAndPorts(baseImage, ports)
	if err != nil {
		return nil, err
	}
	image.AsImageStream = true
	image.TagDirectly = true
	image.ObjectName = name
	image.Tag = "from"

	pipeline, err := app.NewPipelineBuilder(name, nil, false).To(name).NewBuildPipeline(name, image, repo)
	if err != nil {
		return nil, err
	}

	// TODO: this should not be necessary
	pipeline.Build.Source.Name = name
	pipeline.Build.Source.DockerfileContents = fakeDockerfile
	pipeline.Name = name
	pipeline.Image.ObjectName = name
	glog.V(4).Infof("created pipeline %+v", pipeline)

	pipelines = append(pipelines, pipeline)

	var errs []error

	// create deployments for each formation
	var group app.PipelineGroup
	for _, component := range formations.List() {
		componentName := fmt.Sprintf("%s-%s", name, component)