zip

Documentation

Overview

Package zip provides support for reading and writing ZIP archives.

See: http://www.pkware.com/documents/casestudies/APPNOTE.TXT

This package does not support ZIP64 or disk spanning.

Index

• Constants
• Variables
• type File
  • func (f *File) Open() (rc io.ReadCloser, err error)
• type FileHeader
  • func FileInfoHeader(fi os.FileInfo) (*FileHeader, error)
  • func (h *FileHeader) FileInfo() os.FileInfo
  • func (h *FileHeader) ModTime() time.Time
  • func (h *FileHeader) Mode() (mode os.FileMode)
  • func (h *FileHeader) SetModTime(t time.Time)
  • func (h *FileHeader) SetMode(mode os.FileMode)
• type ReadCloser
  • func OpenReader(name string) (*ReadCloser, error)
  • func (rc *ReadCloser) Close() error
• type Reader
  • func NewReader(r io.ReaderAt, size int64) (*Reader, error)
• type Writer
  • func NewWriter(w io.Writer) *Writer
  • func (w *Writer) Close() error
  • func (w *Writer) Create(name string) (io.Writer, error)
  • func (w *Writer) CreateHeader(fh *FileHeader) (io.Writer, error)

Examples

• Reader
• Writer

Constants

const (
	Store   uint16 = 0
	Deflate uint16 = 8
)

Compression methods.

Variables

var (
	ErrFormat    = errors.New("zip: not a valid zip file")
	ErrAlgorithm = errors.New("zip: unsupported compression algorithm")
	ErrChecksum  = errors.New("zip: checksum error")
)

Types

type File

type File struct {
	FileHeader
	// contains filtered or unexported fields
}

func (*File) Open

func (f *File) Open() (rc io.ReadCloser, err error)

Open returns a ReadCloser that provides access to the File's contents. Multiple files may be read concurrently.

type FileHeader

type FileHeader struct {
	Name             string
	CreatorVersion   uint16
	ReaderVersion    uint16
	Flags            uint16
	Method           uint16
	ModifiedTime     uint16 // MS-DOS time
	ModifiedDate     uint16 // MS-DOS date
	CRC32            uint32
	CompressedSize   uint32
	UncompressedSize uint32
	Extra            []byte
	ExternalAttrs    uint32 // Meaning depends on CreatorVersion
	Comment          string
}

func FileInfoHeader

func FileInfoHeader(fi os.FileInfo) (*FileHeader, error)

FileInfoHeader creates a partially-populated FileHeader from an os.FileInfo.

func (*FileHeader) FileInfo

func (h *FileHeader) FileInfo() os.FileInfo

FileInfo returns an os.FileInfo for the FileHeader.

func (*FileHeader) ModTime

func (h *FileHeader) ModTime() time.Time

ModTime returns the modification time. The resolution is 2s.

func (*FileHeader) Mode

func (h *FileHeader) Mode() (mode os.FileMode)

Mode returns the permission and mode bits for the FileHeader.

func (*FileHeader) SetModTime

func (h *FileHeader) SetModTime(t time.Time)

SetModTime sets the ModifiedTime and ModifiedDate fields to the given time. The resolution is 2s.

func (*FileHeader) SetMode

func (h *FileHeader) SetMode(mode os.FileMode)

SetMode changes the permission and mode bits for the FileHeader.

type ReadCloser

type ReadCloser struct {
	Reader
	// contains filtered or unexported fields
}

func OpenReader

func OpenReader(name string) (*ReadCloser, error)

OpenReader will open the Zip file specified by name and return a ReadCloser.

func (*ReadCloser) Close

func (rc *ReadCloser) Close() error

Close closes the Zip file, rendering it unusable for I/O.

type Reader

type Reader struct {
	File    []*File
	Comment string
	// contains filtered or unexported fields
}

Example

package main

import (
	"archive/zip"
	"fmt"
	"io"
	"log"
	"os"
)

func main() {
	// Open a zip archive for reading.
	r, err := zip.OpenReader("testdata/readme.zip")
	if err != nil {
		log.Fatal(err)
	}
	defer r.Close()

	// Iterate through the files in the archive,
	// printing some of their contents.
	for _, f := range r.File {
		fmt.Printf("Contents of %s:\n", f.Name)
		rc, err := f.Open()
		if err != nil {
			log.Fatal(err)
		}
		_, err = io.CopyN(os.Stdout, rc, 68)
		if err != nil {
			log.Fatal(err)
		}
		rc.Close()
		fmt.Println()
	}
}

Output:

Contents of README:
This is the source code repository for the Go programming language.

func NewReader

func NewReader(r io.ReaderAt, size int64) (*Reader, error)

NewReader returns a new Reader reading from r, which is assumed to have the given size in bytes.

type Writer

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

Writer implements a zip file writer.

Example

package main

import (
	"archive/zip"
	"bytes"
	"log"
)

func main() {
	// Create a buffer to write our archive to.
	buf := new(bytes.Buffer)

	// Create a new zip archive.
	w := zip.NewWriter(buf)

	// Add some files to the archive.
	var files = []struct {
		Name, Body string
	}{
		{"readme.txt", "This archive contains some text files."},
		{"gopher.txt", "Gopher names:\nGeorge\nGeoffrey\nGonzo"},
		{"todo.txt", "Get animal handling licence.\nWrite more examples."},
	}
	for _, file := range files {
		f, err := w.Create(file.Name)
		if err != nil {
			log.Fatal(err)
		}
		_, err = f.Write([]byte(file.Body))
		if err != nil {
			log.Fatal(err)
		}
	}

	// Make sure to check the error on Close.
	err := w.Close()
	if err != nil {
		log.Fatal(err)
	}
}

func NewWriter

func NewWriter(w io.Writer) *Writer

NewWriter returns a new Writer writing a zip file to w.

func (*Writer) Close

func (w *Writer) Close() error

Close finishes writing the zip file by writing the central directory. It does not (and can not) close the underlying writer.

func (*Writer) Create

func (w *Writer) Create(name string) (io.Writer, error)

Create adds a file to the zip file using the provided name. It returns a Writer to which the file contents should be written. The file's contents must be written to the io.Writer before the next call to Create, CreateHeader, or Close.

func (*Writer) CreateHeader

func (w *Writer) CreateHeader(fh *FileHeader) (io.Writer, error)

CreateHeader adds a file to the zip file using the provided FileHeader for the file metadata. It returns a Writer to which the file contents should be written. The file's contents must be written to the io.Writer before the next call to Create, CreateHeader, or Close.