BNDL

The reference encoding / decoding library for the BNDL file format.

Also contains a CLI tool (makebndl) to create BNDL files from the command line, as well as an example implementation of a loader for BNDL files in the browser.

BNDL is an experimental file format for bundling arbitrary files as binary bundle for consumption in JavaScript applications. More information on this here.

Installing

With npm do :

npm install bndl

To be able to use the CLI tool globally do :

npm install bndl -g

Usage

Encoding

var bndl = require('bndl');
 
// this will create a bundle with a file generated from code
 
var arrayBuffer = bndl.encode({
    'test.bin': {
        type: 'bin',
        data: (new Uint8Array([1,2,3,4])).buffer
    }
});
 
console.log(arrayBuffer);

var bndl = require('bndl'),
    fs = require('fs');
 
// this will create a bundle containing two files from the file system
 
var fileContent1 = fs.readFileSync('somefile.png'),
    fileContent2 = fs.readFileSync('someotherfile.png');
 
var arrayBuffer = bndl.encode({
    'somefile.png': {
        type: 'png',
        data: (new Uint8Array(fileContent1)).buffer
    },
    'someotherfile.png': {
        type: 'png',
        data: (new Uint8Array(fileContent2)).buffer
    }
});
 
console.log(arrayBuffer);

Decoding

var bndl = require('bndl');
 
// assume that arrayBuffer is an ArrayBuffer with the content of a valid BNDL file
 
var data = bndl.decode(arrayBuffer);
 
console.log(data); // a json containing the source arrayBuffer and a description of each files

Example web loader

var BndlLoader = require('bndl/src/loader');
 
var loader = new BndlLoader ({
    bin: function (arrayBuffer, infos) {
        // function to use to decode the files associated with the type identifier "bin"
        // infos contains the file description (type, start position in the ArrayBuffer and length)
        return new Uint8Array(arrayBuffer, infos.start, infos.length);
    }
});
 
loader.load('./mybundle.bndl', function (files) {
    console.log(files);
});

See online examples with images and 3D models.

CLI Usage

makebndl inputFileGlob:type ... -o outputFile [OPTIONS]

Options

• -q, --quiet : Quiet mode. Silence the output to the console.

Examples

Create a bundle containing all the txt files in the directory.

makebndl "*.txt:txt" -o texts.bndl

Create a bundle containing all the png and jpg files in the directory while giving them the same type identifier.

makebndl "*.(png|jpg):img" -o images.bndl

Create a bundle from specific files.

makebndl model.obj:obj texture.jpg:img -o resources.bndl

API

bndl.encode(data)

• data : A literal containing multiple files descriptions as literals. The keys of the data object are used as file identifier.
• type : Type of the file, a string identifying the type of the object.
• data : ArrayBuffer representing the content of the file.

bndl.decode(bndlData)

• bndlData : An ArrayBuffer with the content of a BNDL file.

Returns a literal containing the source arrayBuffer and the list of files with their associated type, start position in the arrayBuffer and content length.

{
    "version": 1,
    "arrayBuffer": ArrayBuffer(312932),
    "files": {
        "images/image1.png": { "type":"img", "start":128, "length":68209 },
        "images/image2.png": { "type":"img", "start":68340, "length":76320 },
        "images/image3.png": { "type":"img", "start":144660, "length":85165 },
        "images/image4.png": { "type":"img", "start":229828, "length":83104 }
    }
}

Changelog

1.0.2 (2019-09-28) :

• Update dependencies.

1.0.1 (2019-07-06) :

• Update dependencies.

1.0.0 (2018-01-07) :

• First implementation, with full support for the first version of the format.

License

MIT