tar-fs

What is tar-fs?

The tar-fs npm package is a Node.js module that allows you to interact with tarball (.tar) files. It provides functionality to pack and extract tarball files using file system streams. It is a high-level module that makes it easy to create and extract tar files in a Node.js environment.

What are tar-fs's main functionalities?

Packing files into a tarball

This feature allows you to pack a directory into a tarball. The code sample demonstrates how to pack the contents of '/source/directory' into a tarball named 'archive.tar' located at '/destination/'.

const tar = require('tar-fs');
const fs = require('fs');

let pack = tar.pack('/source/directory')
  .pipe(fs.createWriteStream('/destination/archive.tar'));

Extracting files from a tarball

This feature allows you to extract the contents of a tarball into a directory. The code sample demonstrates how to extract the contents of 'archive.tar' from '/source/' into the '/destination/directory'.

const tar = require('tar-fs');
const fs = require('fs');

fs.createReadStream('/source/archive.tar')
  .pipe(tar.extract('/destination/directory'));

Other packages similar to tar-fs

tar

The 'tar' package is another Node.js module for manipulating tar files. It provides similar functionality to tar-fs, such as packing and extracting tarball files. However, it also includes support for additional features like gzip compression and incremental backups.

archiver

Archiver is a streaming interface for archive generation, supporting ZIP and TAR formats. It offers more format options than tar-fs and includes features like appending to existing archives and setting global archive headers.

README

tar-fs

filesystem bindings for tar-stream.

npm install tar-fs

Usage

tar-fs allows you to pack directories into tarballs and extract tarballs into directories.

var tar = require('tar-fs')
var fs = require('fs')

// packing a directory
tar.pack('./my-directory').pipe(fs.createWriteStream('my-tarball.tar'))

// extracting a directory
fs.createReadStream('my-other-tarball.tar').pipe(tar.extract('./my-other-directory'))

To ignore various files when packing or extracting add a ignore function to the options

var pack = tar.pack('./my-directory', {
  ignore: function(name) {
    return path.extname(name) === '.bin' // ignore .bin files when packing
  }
})

var extract = tar.extract('./my-other-directory', {
  ignore: function(name) {
    return path.extname(name) === '.bin' // ignore .bin files inside the tarball when extracing
  }
})

If you want to modify the headers when packing/extracting add a map function to the options

var pack = tar.pack('./my-directory', {
  map: function(header) {
    header.name = 'prefixed/'+header.name
    return header
  }
})

var extract = tar.pack('./my-directory', {
  map: function(header) {
    header.name = 'another-prefix/'+header.name
    return header
  }
})

Similarly you can use mapStream incase you wanna modify the input/output file streams

var pack = tar.pack('./my-directory', {
  mapStream: function(fileStream) {
    return fileStream.pipe(someTransform)
  }
})

var extract = tar.extract('./my-directory', {
  mapStream: function(fileStream) {
    return fileStream.pipe(someTransform)
  }
})

Set options.fmode and options.dmode to ensure that files/directories extracted have the corresponding modes

var extract = tar.extract('./my-directory', {
  dmode: 0555, // all dirs and files should be readable
  fmode: 0444
})

It can be useful to use dmode and fmode if you are packing/unpacking tarballs between *nix/windows to ensure that all files/directories unpacked are readable.

Set options.strict to false if you want to ignore errors due to unsupported entry types (like device files)

Copy a directory

Copying a directory with permissions and mtime intact is as simple as

tar.pack('source-directory').pipe(tar.extract('dest-directory'))

Performance

Packing and extracting a 6.1 GB with 2496 directories and 2398 files yields the following results on my Macbook Air. See the benchmark here

• tar-fs: 34.261 ms
• node-tar: 366.123 ms (or 10x slower)

License

MIT