Using CakePHP and RPX for Social Authentication

I am working on a social network application where I want to allow users to import their information from another social network or service that provides an open authentication. I looked at Facebook connect and Twitter sign on but after doing research the easiest solution for me was using RPX's hosted solution. It took me about 10 minutes to implement and maybe another hour to fine tune to my needs.

To start you will need to register with RPX and then set up your widget. Some of the providers (such as Facebook and Twitter) need you to set up the application on their network first and then they will provide you with an API key that you can then plug into RPX.

After setting up the widget they will provide you with some code to copy and paste, there really isn't any modifications needed to the code except setting the token_url which is used as a redirect url once the user has been authenticated. You will probably want to set the token_url to a registration page where the user can enter a username and password for CakePHP's authentication component.

Once you have everything in place you will need to set up some code for the action that corresponds with the token_url. First you will need to receive the token from RPX used to retrieve the user's data, then you will need to request the user's info using their API. Here is the code that I am using in my action.

App::import('Core', 'HttpSocket');
$http = new HttpSocket();

$token = $this->params['form']['token'];
$results = $http->post(
'token' => $token,
'apiKey' => 'YOUR-API-KEY-HERE'
$user = json_decode($results);

I am using CakePHP's built in HttpSocket class to request the user's information. The information sent from RPX is in JSON format so I used PHP 5's built in json_decode method to create an object out of the json. Now you would most likely create a new user record and save the information received from RPX and in the view display a form to collect the rest of the user's credentials such as username and password.

That's it, it's very simple to use. If you have any questions leave a comment and I will get back to you as soon as possible.