tarfs

README

go-tarfs

Read a tar file contents using go1.16 io/fs abstraction

Usage

⚠️ go-tarfs needs go>=1.17

Install:

go get github.com/nlepage/go-tarfs

Use:

package main

import (
    "os"

    tarfs "github.com/nlepage/go-tarfs"
)

func main() {
    tf, err := os.Open("path/to/archive.tar")
    if err != nil {
        panic(err)
    }
    defer tf.Close()

    tfs, err := tarfs.New(tf)
    if err != nil {
        panic(err)
    }

    f, err := tfs.Open("path/to/some/file")
    if err != nil {
        panic(err)
    }
    defer f.Close() // frees the associated reader

    // use f...
}

More information at pkg.go.dev/github.com/nlepage/go-tarfs

Long living fs.FS

The io.Reader given to tarfs.New must stay opened while using the returned fs.FS (this is true only if the io.Reader implements io.ReaderAt).

Memory usage

Since v1.2.0 files content are not stored in memory anymore if the io.Reader given to tarfs.New implements io.ReaderAt.

Symbolic links

For now, no effort is done to support symbolic links.

Show your support

Give a ⭐️ if this project helped you!

Contributors ✨

Thanks goes to these wonderful people (emoji key):

Nicolas Lepage 💻 ⚠️ 💡 🚧 👀

Jonas Plum ⚠️ 💻

MengYX 🐛 💻

Andrey Dyatlov 🐛 💻 ⚠️

Joe Lanford 💻 👀

This project follows the all-contributors specification. Contributions of any kind welcome!

📝 License

This project is unlicensed, it is free and unencumbered software released into the public domain.

Documentation

Overview

Example (HttpFileServer)

ExampleHTTPFileServer demonstrates how to serve the contents of a tar file using HTTP

tf, err := os.Open("test.tar")
if err != nil {
	panic(err)
}
defer tf.Close()

tfs, err := tarfs.New(tf)
if err != nil {
	panic(err)
}

srv := httptest.NewServer(http.FileServer(http.FS(tfs)))
defer srv.Close()

res, err := srv.Client().Get(srv.URL + "/dir1/dir11/file111")
if err != nil {
	panic(err)
}

if _, err := io.Copy(os.Stdout, res.Body); err != nil {
	panic(err)
}
res.Body.Close()

Output:

file111

Example (Stat)

Example_stat demonstrates how to read a file info from within a tar

tf, err := os.Open("test.tar")
if err != nil {
	panic(err)
}
defer tf.Close()

tfs, err := tarfs.New(tf)
if err != nil {
	panic(err)
}

fi, err := fs.Stat(tfs, "dir1/dir11/file111")
if err != nil {
	panic(err)
}

fmt.Println(fi.Name())
fmt.Println(fi.IsDir())
fmt.Println(fi.Size())

Output:

file111
false
7

Index

• Variables
• func New(r io.Reader) (fs.FS, error)

Examples

• Package (HttpFileServer)
• Package (Stat)

Variables

var (
	ErrNotDir = errors.New("not a directory")
	ErrDir    = errors.New("is a directory")
)

Generic errors

Functions

func New

func New(r io.Reader) (fs.FS, error)

New creates a new tar fs.FS from r. If r implements io.ReaderAt: - files content are not stored in memory - r must stay opened while using the fs.FS