@obsidize/tar-browserify

Simple utility for packing and unpacking tar files in the browser.

Highlights:

- Zero dependencies
- No node-based requires/imports (fully compatible in browser)
- Inline extraction tools (examples below)
- Builder pattern for creating tarball files in-memory (examples below)
- Supports PAX header reading/writing

Pairs well with these modules:

- pako for gzip / unzip
- path-browserify to further process raw file names

Installation

``bash
npm install -P -E @obsidize/tar-browserify
`

Usage

$3

`typescript
import { ungzip } from 'pako';
import { Archive } from '@obsidize/tar-browserify';

async function readTarFile() {
const response = await fetch('url/to/some/file.tar.gz');
const gzBuffer = await response.arrayBuffer();
const tarBuffer = ungzip(gzBuffer);

for await (const entry of Archive.read(tarBuffer)) {
if (entry.isFile()) {
console.log(read tar file: ${entry.fileName} with content length ${entry.content!.byteLength});
console.log(file text contents: ${entry.text()});
// TODO: do something interesting with the file
}
}
}

readTarFile().catch(console.error);
`

$3

`typescript
import { gzip } from 'pako';
import { Archive } from '@obsidize/tar-browserify';

async function writeTarFile() {
const tarBuffer = new Archive()
.addDirectory('MyStuff')
.addTextFile('MyStuff/todo.txt', 'This is my TODO list')
.addBinaryFile('MyStuff/some-raw-file.obj', Uint8Array.from([1, 2, 3, 4, 5]))
.addDirectory('Nested1')
.addDirectory('Nested1/Nested2')
.addBinaryFile('Nested1/Nested2/supersecret.bin', Uint8Array.from([6, 7, 8, 9]))
.toUint8Array();

const gzBuffer = gzip(tarBuffer);
const fileToSend = new File([gzBuffer], 'my-awesome-new-file.tar.gz');
// TODO: send the new file somewhere
}

writeTarFile().catch(console.error);
`

$3

`typescript
import { gzip, ungzip } from 'pako';
import { Archive } from '@obsidize/tar-browserify';

async function modifyTarFile() {
const response = await fetch('url/to/some/file.tar.gz');
const gzBuffer = await response.arrayBuffer();
const tarBuffer = ungzip(gzBuffer);
const archive = await Archive.extract(tarBuffer);

const updatedTarBuffer = archive
.removeEntriesWhere((entry) => /unwanted\-file\-name\.txt/.test(entry.fileName))
.cleanAllHeaders() // remove unwanted metadata
.addTextFile('new text file.txt', 'this was added to the original tar file!')
.toUint8Array();

const updatedGzBuffer = gzip(updatedTarBuffer);
const fileToSend = new File([updatedGzBuffer], 'my-awesome-edited-file.tar.gz');
// TODO: send the modified file somewhere
}

modifyTarFile().catch(console.error);
`

$3

For very large files (>= 50MB) it is better to use the AsyncUint8ArrayLike
interface for loading the file in chunks (either from disk or over a network)

`typescript
import { Archive, AsyncUint8ArrayLike } from '@obsidize/tar-browserify';

async function readBigTarFile() {
const customAsyncBuffer: AsyncUint8ArrayLike = {
byteLength: 12345, // the file length in bytes must be known ahead of time
read: (offset: number, length: number): Promise => / TODO: return chunk from disk or network request /
};

for await (const entry of Archive.read(customAsyncBuffer)) {
if (!entry.isFile()) {
continue;
}

let totalBytesRead = 0;

for await (const chunk of entry.getContentChunks()) {
totalBytesRead += chunk.byteLength;
// TODO: do something interesting with the data chunk
}
}
}

readBigTarFile().catch(console.error);
`

API

Full API docs can be found in the repo GitHub Docs Page

Testing

This module has a full Test Suite
to ensure breaking changes are not introduced, and is tested against the output
of the node-tar package to ensure stability.

- npm test - run unit tests with live-reload.
- npm run coverage` - perform a single-pass of unit tests with code-coverage display.