omnia

Omnia

Omnia is a lightweight module system for building very large Node.js applications.

Core Features

• Built in clustering/crash protection
• A module system

Installation

$ npm install omnia

Module System

Building large Node.js apps is hard. The larger they grow, the more difficult it becomes to not throw yourself from your 4th story office window onto the delicious mediterranean food truck below. This is where the module system comes in.

It's quite simple. Create a folder that will contain your modules. Each module is a single file that looks like this.

module.exports = function (app, register) {
  // module code here
};

You could, for instance, have 2 modules in your modules folder.

// cats
module.exports = function (app, register) {
 
  app.put('/cats/:name', function (req, res) {
    var catName = req.params.name;
    var catData = req.body.catData;
 
    // add cat to cat database
 
    res.end(200);
  });
 
  function speak () {
    console.log("meow!");
  }
}
 
  register({
    speak: speak
  });
};

register() must be called to register the module with Omnia.

// dogs
module.exports = function (app, cats, register) {
 
  app.put('/dogs/:name', function (req, res) {
    var dogName = req.params.name;
    var dogData = req.body.dogData;
 
    // add dog to dog database
 
    res.end(200);
  });
 
  // access to dependencies
  cats.speak();
 
  register();
};

You modules folder must contain an index.json file that looks like this:

{
  "cats": {
    "dependencies": ["app"]
  },
  "dogs": {
    "dependencies": ["app", "cats"]
  }
}

And finally, your main server.js (or whatever you typically name this file) will look something like this:

var omnia = require('omnia');
var express = require('express');
 
var app = express();
 
omnia.register("app", app); // this is how you register arbitrary objects so modules have access to them
omnia.initialize(__dirname + '/modules/'); // trailing slash is optional
 
omnia.run(app, 5000); // omnia.run takes a callback of the form function (req, res) { . . . }

Module Directory Structure

This describes the above example.

/app
 |-- server.js
 |-- app/modules
      |-- cats.js
      |-- dogs.js
      |-- index.json

Clustering

Clustering is built into Omnia. When using environments like Heroku (like we do), it's difficult (impossible) to use tools like Forever or PM2.

omnia.run(app, 5000);

Calling this will start your application on all available cores, and will keep at least a single instance alive in the event of a crash or an exception. If you have no need for this, you can simply pass a callback to omnia.initialize which will execute once omnia has finished initializing.

var http = require('http');
var omnia = require('omnia');
var express = require('express');
 
var app = express();
 
omnia.register("app", app);
omnia.initialize(__dirname + '/modules/', function () {
    http.createServer(app).listen(5000);
});