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.

It doesn't gunzip for you, so if you want to extract a .tar.gz with this you'll need to use something like gunzip-maybe in addition to this.

1var tar = require('tar-fs')
2var fs = require('fs')
3
4// packing a directory
5tar.pack('./my-directory').pipe(fs.createWriteStream('my-tarball.tar'))
6
7// extracting a directory
8fs.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. ignore is also an alias for filter. Additionally you get header if you use ignore while extracting. That way you could also filter by metadata.

1var pack = tar.pack('./my-directory', {
2  ignore: function(name) {
3    return path.extname(name) === '.bin' // ignore .bin files when packing
4  }
5})
6
7var extract = tar.extract('./my-other-directory', {
8  ignore: function(name) {
9    return path.extname(name) === '.bin' // ignore .bin files inside the tarball when extracing
10  }
11})
12
13var extractFilesDirs = tar.extract('./my-other-other-directory', {
14  ignore: function(_, header) {
15    // pass files & directories, ignore e.g. symlinks
16    return header.type !== 'file' && header.type !== 'directory'
17  }
18})

You can also specify which entries to pack using the entries option

1var pack = tar.pack('./my-directory', {
2  entries: ['file1', 'subdir/file2'] // only the specific entries will be packed
3})

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

1var pack = tar.pack('./my-directory', {
2  map: function(header) {
3    header.name = 'prefixed/'+header.name
4    return header
5  }
6})
7
8var extract = tar.extract('./my-directory', {
9  map: function(header) {
10    header.name = 'another-prefix/'+header.name
11    return header
12  }
13})

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

1var pack = tar.pack('./my-directory', {
2  mapStream: function(fileStream, header) {
3    if (path.extname(header.name) === '.js') {
4      return fileStream.pipe(someTransform)
5    }
6    return fileStream;
7  }
8})
9
10var extract = tar.extract('./my-directory', {
11  mapStream: function(fileStream, header) {
12    if (path.extname(header.name) === '.js') {
13      return fileStream.pipe(someTransform)
14    }
15    return fileStream;
16  }
17})

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

1var extract = tar.extract('./my-directory', {
2  dmode: parseInt(555, 8), // all dirs should be readable
3  fmode: parseInt(444, 8) // all files should be readable
4})

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.

Alternatively you can set options.readable and/or options.writable to set the dmode and fmode to readable/writable.

1var extract = tar.extract('./my-directory', {
2  readable: true, // all dirs and files should be readable
3  writable: true, // all dirs and files should be writable
4})

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

To dereference symlinks (pack the contents of the symlink instead of the link itself) set options.dereference to true.

Copy a directory

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

1tar.pack('source-directory').pipe(tar.extract('dest-directory'))

Interaction with tar-stream

Use finalize: false and the finish hook to leave the pack stream open for further entries (see tar-stream#pack), and use pack to pass an existing pack stream.

1var mypack = tar.pack('./my-directory', {
2  finalize: false,
3  finish: function(sameAsMypack) {
4    mypack.entry({name: 'generated-file.txt'}, "hello")
5    tar.pack('./other-directory', {
6      pack: sameAsMypack
7    })
8  }
9})

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