archive

Documentation

Index

• Constants
• func ApplyLayer(dest string, layer Archive) error
• func CmdStream(cmd *exec.Cmd, input *string, atEnd func()) (io.Reader, error)
• func CopyFileWithTar(src, dst string) error
• func CopyWithTar(src, dst string) error
• func Tar(path string, compression Compression) (io.Reader, error)
• func TarFilter(path string, options *TarOptions) (io.Reader, error)
• func TarUntar(src string, filter []string, dst string) error
• func Untar(archive io.Reader, path string, options *TarOptions) error
• func UntarPath(src, dst string) error
• type Archive
  • func ExportChanges(root, rw string) (Archive, error)
• type Change
  • func Changes(layers []string, rw string) ([]Change, error)
  • func ChangesDirs(newDir, oldDir string) ([]Change, error)
  • func (change *Change) String() string
• type ChangeType
• type Compression
  • func DetectCompression(source []byte) Compression
  • func (compression *Compression) Extension() string
  • func (compression *Compression) Flag() string
• type FileInfo
  • func (info *FileInfo) Changes(oldInfo *FileInfo) []Change
  • func (root *FileInfo) LookUp(path string) *FileInfo
• type TarOptions
• type TempArchive
  • func NewTempArchive(src Archive, dir string) (*TempArchive, error)
  • func (archive *TempArchive) Read(data []byte) (int, error)

Constants

const (
	ChangeModify = iota
	ChangeAdd
	ChangeDelete
)

Functions

func ApplyLayer

func ApplyLayer(dest string, layer Archive) error

ApplyLayer parses a diff in the standard layer format from `layer`, and applies it to the directory `dest`.

func CmdStream

func CmdStream(cmd *exec.Cmd, input *string, atEnd func()) (io.Reader, error)

CmdStream executes a command, and returns its stdout as a stream. If the command fails to run or doesn't complete successfully, an error will be returned, including anything written on stderr.

func CopyFileWithTar

func CopyFileWithTar(src, dst string) error

CopyFileWithTar emulates the behavior of the 'cp' command-line for a single file. It copies a regular file from path `src` to path `dst`, and preserves all its metadata.

If `dst` ends with a trailing slash '/', the final destination path will be `dst/base(src)`.

func CopyWithTar

func CopyWithTar(src, dst string) error

CopyWithTar creates a tar archive of filesystem path `src`, and unpacks it at filesystem path `dst`. The archive is streamed directly with fixed buffering and no intermediary disk IO.

func Tar

func Tar(path string, compression Compression) (io.Reader, error)

Tar creates an archive from the directory at `path`, and returns it as a stream of bytes.

func TarFilter

func TarFilter(path string, options *TarOptions) (io.Reader, error)

Tar creates an archive from the directory at `path`, only including files whose relative paths are included in `filter`. If `filter` is nil, then all files are included.

func TarUntar

func TarUntar(src string, filter []string, dst string) error

TarUntar is a convenience function which calls Tar and Untar, with the output of one piped into the other. If either Tar or Untar fails, TarUntar aborts and returns the error.

func Untar

func Untar(archive io.Reader, path string, options *TarOptions) error

Untar reads a stream of bytes from `archive`, parses it as a tar archive, and unpacks it into the directory at `path`. The archive may be compressed with one of the following algorithms:

identity (uncompressed), gzip, bzip2, xz.

FIXME: specify behavior when target path exists vs. doesn't exist.

func UntarPath

func UntarPath(src, dst string) error

UntarPath is a convenience function which looks for an archive at filesystem path `src`, and unpacks it at `dst`.

Types

type Archive

type Archive io.Reader

func ExportChanges

func ExportChanges(root, rw string) (Archive, error)

type Change

type Change struct {
	Path string
	Kind ChangeType
}

func Changes

func Changes(layers []string, rw string) ([]Change, error)

func ChangesDirs

func ChangesDirs(newDir, oldDir string) ([]Change, error)

Compare two directories and generate an array of Change objects describing the changes

func (*Change) String

func (change *Change) String() string

type ChangeType

type ChangeType int

type Compression

type Compression int

const (
	Uncompressed Compression = iota
	Bzip2
	Gzip
	Xz
)

func DetectCompression

func DetectCompression(source []byte) Compression

func (*Compression) Extension

func (compression *Compression) Extension() string

func (*Compression) Flag

func (compression *Compression) Flag() string

type FileInfo

type FileInfo struct {
	// contains filtered or unexported fields
}

func (*FileInfo) Changes

func (info *FileInfo) Changes(oldInfo *FileInfo) []Change

func (*FileInfo) LookUp

func (root *FileInfo) LookUp(path string) *FileInfo

type TarOptions

type TarOptions struct {
	Includes    []string
	Excludes    []string
	Recursive   bool
	Compression Compression
	CreateFiles []string
}

type TempArchive

type TempArchive struct {
	*os.File
	Size int64 // Pre-computed from Stat().Size() as a convenience
}

func NewTempArchive

func NewTempArchive(src Archive, dir string) (*TempArchive, error)

NewTempArchive reads the content of src into a temporary file, and returns the contents of that file as an archive. The archive can only be read once - as soon as reading completes, the file will be deleted.

func (*TempArchive) Read

func (archive *TempArchive) Read(data []byte) (int, error)