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);

    }
}

I presented this talk on the Soft Expo 2010 – the largest software fair in Bangladesh. The intention was to clear some of the misconception about PHP, the growth of PHP, how it can fit in the enterprise now, etc.

After these, I shed light on some topics that a company/developer should keep in mind in order to write good software in PHP. This was followed by live session on caching, mysql query optimization, use of Xdebug, etc.

So here goes the presentation:

And a big thanks to Ivo Jansch’s “PHP in the real wolrd” presentation, from where I took inspiration.

Cheers!

CodeIgniter is one of my favorite framework and I often use it for developing application quickly. Although it is very flexible in most cases, I find its naming convention to be strict. Many times I have faced this problem when my controller’s class name and a model/library’s class names are the same – a Fatal error is inevitable and I have to forcefully change the name of the conflicting class to something less desirable (say from Users to UsersModel). Today I wanted to end this problem.

So I extended the CI_Router core class and made change to the _validate_request method. Now I can name my controller classes in this fashion: UsersController and it resides on the file system as controllers/UsersController.php. If you’ve tried other established frameworks, you should notice that this naming convention is widely used. So, if you have the same need, then just download the MY_Router.php file and put it on your application/libraries folder. That’s it.

Here is how your controller would start:

<?php

class UsersController extends Controller
{
    public function __construct()
    {
        parent::__construct();
    }
}

At last the phpXperts seminar on “Current Web Trends” have taken place and I was one of the speakers there. Among all the topics, mine was a bit suggestive and naturally a bit less exciting. I spoke about how to become a PHP ninja – what are the characteristics they posses, what are the tools they use, what are the paths they follow etc. It’s actually a follow-up of one of my blog posts: “Becoming a kick-ass PHP ninja“.

Here goes the slides:

All the other slides, pictures, and videos are available here.

Enjoy!

If you are like me, whenever you need to work with a 3rd party API or a gateway, you’d first search in Google for a possible wrapper for it in PHP. When it comes to supporting payment gateways, you get bunch of libraries in the search results who are fundamentally different. Some of them are old PHP 3/4 ones, some are new, some may need PEAR, etc.

As they were not required together in one single project, I used them whenever needed. But in one project, I needed them all. I thoughts it’s a chance and decided to stop using them and wrote my own ones where I can use the same methods for all the gateways.

So, here is an abstract PaymentGateway library which is being extended to be used for three popular payment gateways (Paypal, Authorize.net, and 2Checkout) in order to provide you with a similar way of using them. Note that the libraries are for basic usage only and do not contain options for recurring payments. Without much babble, let’s see a few examples of how you can use them.

You can straight-away download the package with all the libraries, examples, and readme.

Paypal

In order to process payments using Paypal, you’ll need to follow these steps:

1. Send the required information to Paypal (snippet 1). Be sure to specify your Paypal email where you want to receive the funds, the success and failure pages, the IPN page, and the product information. The example has the test mode ON, which you will not need in real scenario.

2. Create a payment success page where Paypal will send your customer after payment.

3. Create a payment failure page where Paypal will send your customer after failed payment.

4. Create a IPN page where Paypal will send payment notification in the background. Make sure you use/remove the test mode in conjunction with step 1. (snippet 2)

< ?php

// Include the paypal library
include_once ('Paypal.php');

// Create an instance of the paypal library
$myPaypal = new Paypal();

// Specify your paypal email
$myPaypal->addField('business', 'YOUR_PAYPAL_EMAIL');

// Specify the currency
$myPaypal->addField('currency_code', 'USD');

// Specify the url where paypal will send the user on success/failure
$myPaypal->addField('return', 'http://YOUR_HOST/payment/paypal_success.php');
$myPaypal->addField('cancel_return', 'http://YOUR_HOST/payment/paypal_failure.php');

// Specify the url where paypal will send the IPN
$myPaypal->addField('notify_url', 'http://YOUR_HOST/payment/paypal_ipn.php');

// Specify the product information
$myPaypal->addField('item_name', 'T-Shirt');
$myPaypal->addField('amount', '9.99');
$myPaypal->addField('item_number', '001');

// Specify any custom value
$myPaypal->addField('custom', 'muri-khao');

// Enable test mode if needed
$myPaypal->enableTestMode();

// Let's start the train!
$myPaypal->submitPayment();

Snippet 1