builder

type Backend interface {
	ImageBackend
	ExecBackend

	// CommitBuildStep creates a new Docker image from the config generated by
	// a build step.
	CommitBuildStep(backend.CommitConfig) (image.ID, error)
	// ContainerCreateWorkdir creates the workdir
	ContainerCreateWorkdir(containerID string) error

	CreateImage(config []byte, parent string) (Image, error)

	ImageCacheBuilder
}

type ExecBackend interface {
	// ContainerAttachRaw attaches to container.
	ContainerAttachRaw(cID string, stdin io.ReadCloser, stdout, stderr io.Writer, stream bool, attached chan struct{}) error
	// ContainerCreateIgnoreImagesArgsEscaped creates a new Docker container and returns potential warnings
	ContainerCreateIgnoreImagesArgsEscaped(config types.ContainerCreateConfig) (container.ContainerCreateCreatedBody, error)
	// ContainerRm removes a container specified by `id`.
	ContainerRm(name string, config *types.ContainerRmConfig) error
	// ContainerKill stops the container execution abruptly.
	ContainerKill(containerID string, sig uint64) error
	// ContainerStart starts a new container
	ContainerStart(containerID string, hostConfig *container.HostConfig, checkpoint string, checkpointDir string) error
	// ContainerWait stops processing until the given container is stopped.
	ContainerWait(ctx context.Context, name string, condition containerpkg.WaitCondition) (<-chan containerpkg.StateStatus, error)
}

type Image interface {
	ImageID() string
	RunConfig() *container.Config
	MarshalJSON() ([]byte, error)
	OperatingSystem() string
}

type ImageBackend interface {
	GetImageAndReleasableLayer(ctx context.Context, refOrID string, opts backend.GetImageAndLayerOptions) (Image, ROLayer, error)
}

type ImageCache interface {
	// GetCache returns a reference to a cached image whose parent equals `parent`
	// and runconfig equals `cfg`. A cache miss is expected to return an empty ID and a nil error.
	GetCache(parentID string, cfg *container.Config) (imageID string, err error)
}

type ImageCacheBuilder interface {
	// MakeImageCache creates a stateful image cache.
	MakeImageCache(cacheFrom []string) ImageCache
}

type ROLayer interface {
	Release() error
	NewRWLayer() (RWLayer, error)
	DiffID() layer.DiffID
}

type RWLayer interface {
	Release() error
	Root() containerfs.ContainerFS
	Commit() (ROLayer, error)
}

type Result struct {
	ImageID   string
	FromImage Image
}

type Source interface {
	// Root returns root path for accessing source
	Root() containerfs.ContainerFS
	// Close allows to signal that the filesystem tree won't be used anymore.
	// For Context implementations using a temporary directory, it is recommended to
	// delete the temporary directory in Close().
	Close() error
	// Hash returns a checksum for a file
	Hash(path string) (string, error)
}