unionfs

Creates a union of multiple fs file systems.

[![][npm-img]][npm-url] [![][travis-badge]][travis-url]

npm install --save unionfs

This module allows you to use multiple objects that have file system fs API at the same time.

``js
import {ufs} from 'unionfs';
import {fs as fs1} from 'memfs';
import * as fs2 from 'fs';

ufs
.use(fs1)
.use(fs2);

ufs.readFileSync(/ ... /);
`

Use this module with [memfs][memfs] and [linkfs][linkfs].
memfs allows you to create virtual in-memory file system. linkfs allows you to redirect fs paths.

You can also use other fs-like objects.

`js
import * as fs from 'fs';
import {Volume} from 'memfs';
import * as MemoryFileSystem from 'memory-fs';
import {ufs} from 'unionfs'


const vol1 = Volume.fromJSON({'/memfs-1': '1'});
const vol2 = Volume.fromJSON({'/memfs-2': '2'});


const memoryFs = new MemoryFileSystem;
memoryFs.writeFileSync('/memory-fs', '3');


ufs
.use(fs)
.use(vol1)
.use(vol2)
.use(memoryFs);

console.log(ufs.readFileSync('/memfs-1', 'utf8')); // 1
console.log(ufs.readFileSync('/memfs-2', 'utf8')); // 2
console.log(ufs.readFileSync('/memory-fs', 'utf8')); // 3
`

You can create a Union instance manually:

`javascript
import {Union} from 'unionfs';

var ufs1 = new Union;
ufs1
.use(fs)
.use(vol);

var ufs2 = new Union;
ufs2
.use(fs)
.use(/.../);
``

[npm-url]: https://www.npmjs.com/package/unionfs
[npm-img]: https://img.shields.io/npm/v/unionfs.svg
[memfs]: https://github.com/streamich/memfs
[unionfs]: https://github.com/streamich/unionfs
[linkfs]: https://github.com/streamich/linkfs
[fs-monkey]: https://github.com/streamich/fs-monkey
[travis-url]: https://travis-ci.org/streamich/unionfs
[travis-badge]: https://travis-ci.org/streamich/unionfs.svg?branch=master

License

Unlicense - public domain.