Facebook API with Node.js

Facebook API is very powerful, it reveals a lot of data. Lets say that we want to work with the Facebook API from node.js to get some data from Facebook.

In this post I will explain how to achieve this task, I assume that you already have a valid access token of a Facebook user, If you didn't reach to this point, this link will show you how to start.

The module
The first thing is to build a module for Node, I want this module to be able to get a Facebook API open graph path (such as: /me/friends) and retrieve the data from Facebook. In this module I choose to work with the https module of node.js, with this module I can make secured requests to Facebook via https.

facebook.js

var https = require('https');

exports.get = function(accessToken, apiPath, callback) {
    // creating options object for the https request
    var options = {
        // the facebook open graph domain
        host: 'graph.facebook.com',

        // secured port, for https
        port: 443,

        // apiPath is the open graph api path
        path: apiPath + '?access_token=' + accessToken,

        // well.. you know...
        method: 'GET'
    };

    // create a buffer to hold the data received
    // from facebook
    var buffer = '';

    // initialize the get request
    var request = https.get(options, function(result){
        result.setEncoding('utf8');

        // each data event of the request receiving
        // chunk, this is where i`m collecting the chunks
        // and put them together into one buffer...
        result.on('data', function(chunk){
            buffer += chunk;
        });

        // all the data received, calling the callback
        // function with the data as a parameter
        result.on('end', function(){
            callback(buffer);
        });
    });
    
    // just in case of an error, prompting a message
    request.on('error', function(e){
        console.log('error from facebook.get(): '
                     + e.message);
    });

    request.end();
}

Now, In your Node.js server, include this facebook module and call the get() function with the open graph api path that you want.

var facebook = require('./facebook');
facebook.get('FB_ACCESS_TOKEN', '/me/friends', function(data){
    console.log(data);
});

The get() function is a generic function, you can call it with your api request path, pass the access token of the current user and a callback function to be called when the data is ready.