Md Emran Hasan

The new Facebook API has already spread over the application developers and if you’re like me, you’ve already got your hands dirty to see how this new thing works. If you have tried to follow the documentation to authorize/get session in your canvas application, it is likely you have already hit roadblocks. Well, I am no savior but I have glued together a few clues and got it working for myself.

I am assuming that you have already created your application by following the Getting Started section from the official documentation. Also, this is for IFrame based applications only.

Enough talking, let’s get some code.

Step 1: Get the new SDK

Download the new SDK from github. We will only need the facebook.php file from the src folder. In our project directory, let’s create a folder called “lib” and put the file there.

Step 2: A configuration file

Let’s now create a configuration file to store our facebook configuration. Let’s name it config.php. Here goes the source:

<?php

define("FACEBOOK_APP_ID", '113795715321151');
define("FACEBOOK_API_KEY", '064baf5fb98de050cd7b9a001ca1988b');
define("FACEBOOK_SECRET_KEY", '430f43c01f6dfe02c284b4545976f9ce');
define("FACEBOOK_CANVAS_URL", 'http://apps.facebook.com/emran-test-app/');

Step 3: Application Main Page

This file will be the main entry point to our facebook application. It just instantiates the facebook object, sets the configuration and checks for a valid session. If it does not find a valid session, it redirects to the login page. For first time visitors, it will be the authorization page. On later requests, the operation will occur in the background – without any user interaction.

<?php

include_once 'lib/facebook.php';
include_once 'config.php';

$facebook = new Facebook(array(
    'appId'  => FACEBOOK_APP_ID,
    'secret' => FACEBOOK_SECRET_KEY,
    'cookie' => true,
    'domain' => 'phpfour.com'
));

$session = $facebook->getSession();

if (!$session) {

    $url = $facebook->getLoginUrl(array(
               'canvas' => 1,
               'fbconnect' => 0
           ));

    echo "<script type='text/javascript'>top.location.href = '$url';</script>";

} else {

    try {

        $uid = $facebook->getUser();
        $me = $facebook->api('/me');

        $updated = date("l, F j, Y", strtotime($me['updated_time']));

        echo "Hello " . $me['name'] . "<br />";
        echo "You last updated your profile on " . $updated;

    } catch (FacebookApiException $e) {

        echo "Error:" . print_r($e, true);

    }
}

The first ever “Facebook Developer Garage” took place in Dhaka, Bangladesh and I am proud to be a part of it. I was one of the speakers of this spectacular event organized by Facebook and IBT bangladesh. I spoke about the recently released Open Stream API from Facebook. It was more of an overview rather than a detail one. Here goes the slides:

I have created a quick start example which outlines both Facebook Connect and the Open Stream API. You can check that here. A blog post covering the steps is coming soon in 3-4 days.

Stay tuned if you have interest in them.

Cheers