Library for reading tar files in the browser
This library is a free InvokIT/js-untar adaptation designed on ES6 syntax.
To use this requires additional library for inflating deflate binary blobs. The pako inflate library is recommended, but you can use any similar library.
I needed to unzip in the browser some .tgz (tarball) files from modules published to registry.npmjs.org in order to extract the raw from their files.
Unfortunately popular libraries were not very helpful in solving my "specific" problem.
JSZip didn't seem to solve it, pako alone didn't help me much, so I found js-untar and the story changed 😀
Tiny source ... untarjs-with-worker.min.js contains 4.1Kb (1.8Kb gzipped)
Call pako in your document
<body>
<script src="path/to/pako_inflate.min.js"></script>
<script src="path/to/your/script.js" type="module"></script>
</body>In your script module
// pako not suport ES6 module yet ... pako stay in `window` object
let pako = window.pako
/**
* import untarjs (basic - expect `Worker` url param) or use `Worker` with `Blob` version
* 'path/to/untarjs-with-worker.min.mjs'
*/
import untarjs from 'path/to/untarjs.min.mjs'
// request your `.tgz` file (get `ArrayBuffer`)
fetch('path/to/file.tgz').then(response => response.arrayBuffer()).then(async buffer => {
// inflate
const inflator = await pako.inflate(buffer)
// get `Array` object(s) file(s) (wit `Worker` url param)
let result = await untarjs(inflator.buffer, 'path/to/untar.worker.min.js')
// show result (`Array`)
console.log(result) // output: > [{...}]
}).catch(console.error)This library returns a Promise(), in the example above was used async/await syntax to save writing.
A "conventional" example would be like this:
fetch('path/to/file.tgz').then(response => response.arrayBuffer()).then(buffer => {
// inflate
const inflator = pako.inflate(buffer)
// get `Array` object(s) file(s) (wit `Worker` url param)
untarjs(inflator.buffer, 'path/to/untar.worker.min.js').then(result => {
// show result (`Array`)
console.log(result) // output: > [{...}]
}).catch(console.error)
}).catch(console.error)The result is an object (Array) containing a collection, you can iterate over them to get your raw data (ArrayBuffer) and use it however you like.
Given the following structure of a .tgz file (hypothetic):
package/
package.json
README.md
lib/
index.js
The expected result would be (output on console.log):
(3) [
0: {
buffer: ArrayBuffer(1936) {}
checksum: 11547
devmajor: 0
devminor: 0
gid: NaN
gname: ""
linkname: ""
mode: "000644 "
mtime: 499162500
name: "package/package.json"
namePrefix: ""
size: 1936
type: "0"
uid: NaN
uname: ""
ustarFormat: "ustar"
version: "00"
}
1: {
buffer: ArrayBuffer(19335) {}
checksum: 10553
devmajor: 0
devminor: 0
gid: NaN
gname: ""
linkname: ""
mode: "000644 "
mtime: 499162500
name: "package/README.md"
namePrefix: ""
size: 19335
type: "0"
uid: NaN
uname: ""
ustarFormat: "ustar"
version: "00"
}
2: {
buffer: ArrayBuffer(41328) {}
checksum: 11477
devmajor: 0
devminor: 0
gid: NaN
gname: ""
linkname: ""
mode: "000644 "
mtime: 499162500
name: "package/lib/index.js"
namePrefix: ""
size: 41328
type: "0"
uid: NaN
uname: ""
ustarFormat: "ustar"
version: "00"
}
length: 3
__proto__: Array(0)
]Where perhaps (matter of opinion) the relevant data of each object is:
- buffer: the raw data of file (
ArrayBuffer) - name: the full pathname of file (
String) - size: the file size in bytes (
Number)
With this information we already have enough to do something 🤔
With this raw data it would be possible to create blobs (Blob) to store in cache (Cache) them in response to requests (if using a ServiceWorker), store them in IndexedDB or whatever else you can imagine.
Enjoy
Adapted pako_inflate.js 1.0.10 to ES6 module: pako_inflate.min.mjs
Methods .blob(), .getBlob(), .readAsString() and .readAsJSON() from the original library (js-untar) were removed in this adaptation.
You must implement your own logic to manipulate the file buffer for desired output.
Any contribution to improving this code is welcome 🎊
MIT License
Copyright (c) 2015 Sebastian Jørgensen
Copyright (c) 2019 Lauro Moraes https://github.com/subversivo58
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.