Question

I’d like to know what are the steps required to create a framework on top of node.js.
I believe this can be a good way to learn, that’s why I’m doing this!

I’ve been checking other micro-frameworks and bigger frameworks but I’m not being able to understand where to start. I’d like your advice on this.

Edit: MVC Framework like Sinatra, Merb, Rails.

Answer 1

For an MVC framework, the basic concepts go something like this (forgive the simplicity):

var view = 'I say, "{{first}} {{second}}".';
var model = {
    first: 'hello',
    second: function(){
        return 'world';
    }   
};

for(item in model){     
    var regex = new RegExp('{{' + item + '}}', 'gi');
    if(typeof(item) == 'function')
        view = view.replace(regex, model[item]());
    else
        view = view.replace(regex, model[item]);
}
console.log(view);

Start as simple as possible and add small enhancements:

• Store views/templates as files. This gives you a chance to play with node.js’s async file I/O.
• Add support for more complex models – repeating items/arrays, objects containing objects
• Add support for templates inside templates
• Fetch your models from an external datasource. CouchDB might be fun.
• Add proper controllers – these objects should know which models go with which views and how to stitch them together
• Map your Http request urls to controllers and actions – /person/55 might fetch a person with id 55 from your data repository, /person/add might bring up a UI to add a person – both use a person controller with views displayed for the appropriate action.

Take a look at mustache.js for a small template engine. Note their terminology differs from mine in examples and code. What I call a view, they call a template and what I call a model, they call a view. It’s a small thing but potentially confusing.

Additional resources:

• A giant list of node modules. Includes templates, database, routing, and full frameworks.
• MVC with Node.js – Which modules?
• Root.js : A Skeletal MVC Framework for Node.js