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ImportJS (For Node.js)#

(For the original library and complete usage instructions, please see:

This library is a Node.js port of ImportJS that allows you to use the same module-loading features offered by ImportJS on the filesystem. The only difference between the browser and Node version is that you must define your modules slightly differently. See below for details.


npm install importjs

And that's it! You can then start using it by simply requiring the importjs module:

var ImportJS = require('importjs');

You will then have access to the library through the variable ImportJS.

Loading Modules

See below for a quick example:

//Load modules dynamically through the filesystem
    baseUrl: '',
    files: {
        tests: {
            Sample: 'Sample.js', //<- File ./tests/Sample.js will be loaded into ImportJS
    ready: function(files) {
        //At this point your modules are good to go, you could use this as an entry point for your application
        var Sample = ImportJS.unpack('tests.Sample');
        var mySample = new Sample();
//Or define modules explicitly at your leisure, unpack when needed.
ImportJS.pack('com.project.MyClass', function(module, exports) {
    function MyClass() { 
    //Just like Node, you can set your exports via 'module.exports' and/or 'exports'
    module.exports = MyClass;
var MyClass = ImportJS.unpack('com.project.MyClass');
var me = new MyClass();

So just like the browser version, you have the option of loading up files dynamically into ImportJS via the preload() function, or just defining them across an arbitrary number of files.

Defining Modules

When dynamically preloading modules via the preload() function, you simply make sure that these other files also contain the require('importjs')' at the top. (Alternatively you could assign it to global.ImportJS if you'd like instead)

var ImportJS = require('importjs');
/* Follow same syntax as browser version of ImportJS */
ImportJS.pack('tests.Sample', function (module) {
    //Module "CodeFile" is included without require() thanks to ImportJS 
    var CodeFile = this.import('some.other.CodeFile');
    this.inject(function() {
        //If you have circular deps, import them here to hoist them up 
    function Sample() { 
        var foo = 'I am a Sample class';
        this.value = function() {
            return foo;
    //Exposes your 'exported' variable 
    module.exports = Sample;

As you can see, this is exactly how you would write code for this library with the browser version (except for the require() of course). One thing to note however, is that you only need to touch ImportJS's rendition of module.exports to store your module. All of your packaged code files can communicate with one another explicitly through ImportJS. In other words, instead of using require() to retrieve your packaged modules within ImportJS's scope, you can simply load them via this.import('').

For the detailed instructions on this library's features, see the test file included in this repo, as well as the docs for the original ImportJS.

Aside: This library also works great with OOPS.js for Node!

Recent Version History


  • Overhaul of original packaging and preloading code (much cleaner read)
  • Removed module.postCompile and added this.inject which accepts a single function
  • Removed alternative import methods for consistency (please use the module id string)
  • Added this.import to replace the use of ImportJS global from within modules
  • New plugin system (see original ImportJS library for details)

Copyrighted © 2015 by Greg McLeod