essence.js

About

Essence.js is a async dependency injection framework to help build loosely coupled Node.js applications. Check out the sample website app to see how essence js goodness helps constructing a web application.

Why?

Creating loosely coupled applications helps to reduce complexity, improve code reusable and make your code more testable.

Install

npm install --save essencejs

Getting Started

// require the EssenceJs class.
var EssenceJs = require("essencejs").EssenceJs;

// create a new instance of EssenceJs.
var essence = new EssenceJs();

// ALTERNATIVELY - to do the same in a single line:
var essence = new (require("essencejs").EssenceJs)();

// add objects to the essence js container
essence.register("message", { text : "thingy bobs" });

// add singleton
var Start = function Start() { this.startedAt = new Date(); };
essence.singleton(Start);

// add factory
var Random = function Random() { this.random = Math.round(Math.random() * 1000); }
essence.factory(Random);

// inject dependencies of a function
essence.inject(function (message, start, random) {
    console.log(message.text,
        "was started at",
        start.startedAt.toLocaleString() + ".",
        "Here is a random number between 0 - 1000 : ",
        random.random);
});

// this returns the console message
    `thingy bobs was started at Mon Dec 22 2014 19:38:53 GMT+0000 (GMT). Here is a random number between 0 - 1000 :  905`

// calling this same inject function again will return
    `thingy bobs was started at Mon Dec 22 2014 19:38:53 GMT+0000 (GMT). Here is a random number between 0 - 1000 :  323`

// the start time will always remain the same for the duration of the node process because it is a singleton.
// the random value will change because a new factory instance is injected every time it is needed.

Testing

To run the nodeunit tests, use:

npm test