Example of twitter authentication in Kohana using Tijs Verkoyen's Twitter SDK

auth.php

<?php

class Controller_Auth extends Controller {
  
  public function action_twitter()
  {
    $twitter = new Twitter(CONSUMER_TOKEN, CONSUMER_SECRET);
    
    // Retrieve Request Token
    $twitter->oAuthRequestToken(CALLBACK_URL); // In this case, should go back to auth/twitter
    
    if ( ! isset($_GET['oauth_token']))
    {
      $twitter->oAuthAuthorize();
    }
    else
    {
      // Retrieves Access Token
      $token = $twitter->oAuthAccessToken($_GET['oauth_token'], $_GET['oauth_verifier']);
      
      if (empty($token) || sizeof($token) < 4)
      {
        // Shouldn't happen, but I've experienced it before
        die('Sorry, try again');
      }
      
      
      // You get the oauth_token, oauth_token_secret, user_id and screen_name variables.
      
      // At this point, do whatever you are going to do (eg. see if a user exists with credentials and log them in, or register new user)
      
      // Since this is likely to be in a popup, you can just hit a callback for the opener
      $this->response->body('<script>window.opener.authCallback();</script>');
    }
  }

}

popup.html

<a href='#" id='twitter_auth'>AUTHENTICATE!</a>

<script>
var authWindow;
function authCallback() {
  authWindow.close();
}

$('#twitter_auth').click(function(e) {
  e.preventDefault();
  authWindow = window.open('auth/twitter', 'auth', 'width=500,height=400');
});
</script>