encoder

Documentation

Overview

Package encoder creates pxar archives.

Encoder writes pxar archive entries in a single sequential pass. It supports both unified (v1) and split (v2) formats via separate io.Writer outputs.

Usage

enc := encoder.NewEncoder(output, nil, &rootMeta, nil)
enc.AddFile(&fileMeta, "hello.txt", []byte("hello world"))
enc.Close()

For split archives, provide a payload writer to NewEncoder and file content is written to the payload stream with PayloadRef entries in the metadata stream.

Directory Nesting

Directories are created with CreateDirectory and finalized with Finish. The encoder maintains a state stack, so Finish closes the most recently opened directory and resumes the parent's context.

Package encoder creates pxar archives.

Index

• type Encoder
  • func NewEncoder(output, payloadOut io.Writer, metadata *pxar.Metadata, prelude []byte) *Encoder
  • func (e *Encoder) AddDevice(metadata *pxar.Metadata, name string, device format.Device) error
  • func (e *Encoder) AddFIFO(metadata *pxar.Metadata, name string) error
  • func (e *Encoder) AddFile(metadata *pxar.Metadata, name string, content []byte) (LinkOffset, error)
  • func (e *Encoder) AddHardlink(name string, target string, targetOffset LinkOffset) error
  • func (e *Encoder) AddSocket(metadata *pxar.Metadata, name string) error
  • func (e *Encoder) AddSymlink(metadata *pxar.Metadata, name string, target string) error
  • func (e *Encoder) Close() error
  • func (e *Encoder) CreateDirectory(name string, metadata *pxar.Metadata) error
  • func (e *Encoder) CreateFile(metadata *pxar.Metadata, name string, size uint64) (*FileWriter, error)
  • func (e *Encoder) Finish() error
• type FileWriter
  • func (fw *FileWriter) Close() error
  • func (fw *FileWriter) FileOffset() LinkOffset
  • func (fw *FileWriter) Write(data []byte) (int, error)
  • func (fw *FileWriter) WriteAll(data []byte) error
• type LinkOffset
  • func (o LinkOffset) Raw() uint64

Types

type Encoder

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

Encoder writes pxar archives.

func NewEncoder

func NewEncoder(output, payloadOut io.Writer, metadata *pxar.Metadata, prelude []byte) *Encoder

NewEncoder creates a new pxar encoder writing to the given writers. If payloadOut is non-nil, the archive is split (v2 format). metadata describes the root directory. prelude is optional v2 prelude data.

func (*Encoder) AddDevice

func (e *Encoder) AddDevice(metadata *pxar.Metadata, name string, device format.Device) error

AddDevice adds a device node.

func (*Encoder) AddFIFO

func (e *Encoder) AddFIFO(metadata *pxar.Metadata, name string) error

AddFIFO adds a named pipe.

func (*Encoder) AddFile

func (e *Encoder) AddFile(metadata *pxar.Metadata, name string, content []byte) (LinkOffset, error)

AddFile adds a complete file to the archive.

func (*Encoder) AddHardlink

func (e *Encoder) AddHardlink(name string, target string, targetOffset LinkOffset) error

AddHardlink adds a hard link.

func (*Encoder) AddSocket

func (e *Encoder) AddSocket(metadata *pxar.Metadata, name string) error

AddSocket adds a named socket.

func (*Encoder) AddSymlink

func (e *Encoder) AddSymlink(metadata *pxar.Metadata, name string, target string) error

AddSymlink adds a symbolic link.

func (*Encoder) Close

func (e *Encoder) Close() error

Close finalizes the archive (writes root goodbye table and finishes).

func (*Encoder) CreateDirectory

func (e *Encoder) CreateDirectory(name string, metadata *pxar.Metadata) error

CreateDirectory pushes a new directory onto the stack.

func (*Encoder) CreateFile

func (e *Encoder) CreateFile(metadata *pxar.Metadata, name string, size uint64) (*FileWriter, error)

CreateFile returns a FileWriter for streaming file content.

func (*Encoder) Finish

func (e *Encoder) Finish() error

Finish finalizes the current directory (pops state, writes goodbye table).

type FileWriter

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

FileWriter writes file content to a pxar archive.

func (*FileWriter) Close

func (fw *FileWriter) Close() error

Close finalizes the file entry.

func (*FileWriter) FileOffset

func (fw *FileWriter) FileOffset() LinkOffset

FileOffset returns the file's offset for use with AddHardlink.

func (*FileWriter) Write

func (fw *FileWriter) Write(data []byte) (int, error)

Write writes data to the file.

func (*FileWriter) WriteAll

func (fw *FileWriter) WriteAll(data []byte) error

WriteAll writes all data to the file.

type LinkOffset

type LinkOffset uint64

LinkOffset represents a file offset usable with AddHardlink.

func (LinkOffset) Raw

func (o LinkOffset) Raw() uint64

Raw returns the raw byte offset.