dl-tar

A Node.js module to download and extract a tar archive with the Observable API

const {readdirSync} = require('fs');
const dlTar = require('dl-tar');

const url = 'https://****.org/my-archive.tar';
/* my-archive
   ├── LICENSE
   ├── README.md
   ├── INSTALL
   └── bin
       └── app.exe
*/

dlTar(url, 'my/dir').subscribe({
  next({entry}) {
    if (entry.remain === 0) {
      console.log(`✓ ${entry.header.name}`);
    }
  },
  complete() {
    readdirSync('my/dir'); //=> ['INSTALL', LICENSE', 'README.md', 'bin']

    console.log('\nCompleted.')
  }
});

✓ bin/
✓ bin/app.exe
✓ README.md
✓ LICENSE
✓ install

Completed.

Installation

Use npm.

npm install dl-tar

API

const dlTar = require('dl-tar');

dlTar(tarArchiveUrl, extractDir [, options])

tarArchiveUrl: string
extractDir: string (a path where the archive will be extracted)
options: Object
Return: Observable (zenparsing's implementation)

When the Observable is subscribed, it starts to download the tar archive, extract it and successively send extraction progress to its Observer.

When the Subscription is unsubscribed, it stops downloading and extracting.

It automatically unzips gzipped archives.

Progress

Every progress object have two properties entry and response.

entry

Type: tar.ReadEntry

An instance of node-tar's ReadEntry object.

For example you can get the progress of each entry as a percentage by 100 - progress.entry.remain / progress.entry.size * 100.

dlTar('https://****.org/my-archive.tar', 'my/dir')
.filter(progress => progress.entry.type === 'File')
.subscribe(progress => {
  console.log(`${(100 - progress.entry.remain / progress.entry.size * 100).toFixed(1)} %`);

  if (progress.entry.remain === 0) {
    console.log(`>> OK ${progress.entry.header.path}`);
  }
});

0.0 %
0.1 %
0.3 %
0.4 %
︙
99.6 %
99.8 %
99.9 %
100.0 %
>> OK bin/app.exe
0.0 %
0.1 %
0.2 %
0.3 %
︙

response

Type: Object {bytes: <number>, headers: <Object>, url: <string>}

response.url is the final redirected URL of the request, response.headers is a response header object derived from http.IncomingMessage, and response.bytes is a total content length of the downloaded archive. content-length header will be converted to number if it's string.

Options

You can pass options to Request and node-tar's Unpack constructor. Note that:

• onentry option is not supported.
• strict option defaults to true, not false.
• strip option defaults to 1, not 0. That means the top level directory is stripped off by default.

License

ISC License © 2017 - 2018 Shinnosuke Watanabe