bsparks/tar-async

Asynchronous Tar implemented in node

Intro

Tar-async is an async approach to Tar in node.

Tar-async does not directly use the filesystem at all. This makes it really easy to use for practically anything. All that's required to tar something is a filename and data.

No compression is used, so an external compression library is necessary. This is by design and not likely to be implemented.

Example

Tar:

var Tar = require('tar-async'), // or require('tar-async').Tar or require('tar-async/tar')
	tape = new Tar({output: require('fs').createWriteStream('out.tar')});

tape.append('test.txt', 'Woohoo!! Tar me up Scotty!', function () {
	tape.close();
});

Simple huh? A Tar instance is an EventEmitter, and emits these events: 'end', 'data' (and maybe 'error' in the future)

Untar:

var Untar = require('tar-async/untar'), // or require('tar-async').Untar
	fs = require('fs'),
	untar = new Untar(function (err, header, fileStream) {
		console.log(header.filename);
		fileStream.on('data', function (data) {
			console.log(data.toString());
		});
	});

fs.createReadStream('out.tar').pipe(untar);

Untar is a Writable Stream, so it's pretty easy to asynchronously untar something.

API

Ok, so you want more detail. Here ya go:

Tar

Tar(opts)

Supported options include:

• recordsPerBlock- number of records in a block, default is 20 (don't change unless you know what you're doing)
• consolidate- default false; whether to consolidate everything into a single directory
• normalize- default true; whether to normalize each file's path
• output- default null; writable stream to stream output to
• allowPipe- default false; allow Stream.pipe (this will cache the stream to get the size)

Tar.append(filepath, input, opts, callback):

• filepath- filepath for file when extracted
• input- string or Buffer
• opts- optional options
  • mode- permissions on the file (default 777)
  • mtime- last modified time in seconds (default current time)
  • uid- owner id (default 0)
  • gid- group id (default 0)
  • size- size of output (default input.length; changing this could lead to bad results)
• callback- optional callback; no parameters; called when a record is written

Untar

Untar(opts, callback)

• opts
  • fileTypes- if not defined, defaults to normal and contiguous files; these are the options (any single one or an array of multiple ones)
    • 'normal'- normal file
    • 'hard-link'- hard link
    • 'symbolic-link'- symbolic link
    • 'character-special'- device files that moves data by characters; this type of file usually has a majorNumber and minorNumber
    • 'block-special'- device files that moves data in blocks; this type of file usually has a majorNumber and minorNumber
    • 'directory'- directory
    • 'fifo'- named pipe; doesn't have data
    • 'contiguous-file'- same as file, but it's allocated contiguously on disk
• callback- callback each time a record is read; parameters are
  • err- only used when checksums don't match
  • header- header data (see header.js for details
  • fileStream- Readable Stream; chunks will be emitted as Buffer objects