Source for file ForceAuthAction.class.php

<?php
/**
 * @since 8/4/06
 * @package polyphony.AbstractActions
 * 
 * @copyright Copyright &copy; 2005, Middlebury College
 * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License (GPL)
 *
 * @version $Id: ForceAuthAction.class.php,v 1.4 2007/09/19 14:04:41 adamfranco Exp $
 */ 
 
require_once(POLYPHONY."/main/library/AbstractActions/Action.class.php");
 
 
/**
 * The ForceAuthAction forces token collection via HTTP Authentication to allow
 * authentication outside of the context of a browser Harmoni-Application
 * environment. For instance, this can be used to authenticate an RSS reader for
 * an RSS feed, or to prompt for authentication for a file that is directly linked
 * from another website.
 * 
 * @since 8/4/06
 * @package polyphony.AbstractActions
 * 
 * @copyright Copyright &copy; 2005, Middlebury College
 * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License (GPL)
 *
 * @version $Id: ForceAuthAction.class.php,v 1.4 2007/09/19 14:04:41 adamfranco Exp $
 */
class ForceAuthAction 
    extends Action
{
        
    /**
     * Check Authorizations
     * 
     * @return boolean 
     * @access public
     * @since 4/26/05
     */
    function isAuthorizedToExecute () {        
        if ($this->isExecutionAuthorized()) {
            return true;    
        }
        
        // if we aren't authorized, check if we are authenticated
        // and try to re-authorize after that.
        if (!$this->isAuthenticated()) {
            $this->authenticate();
            if ($this->isAuthenticated())
                return $this->isExecutionAuthorized();
        } 
        
        return false;
    }
    
    /**
     * Loop through the authentication types and see if the user is authenticated.
     * 
     * @return boolean 
     * @access public
     * @since 8/4/06
     */
    function isAuthenticated () {
        $isAuthenticated = FALSE;
        $authN = Services::getService("AuthN");
        
        // authenticate.
        $authTypes =$authN->getAuthenticationTypes();
        while ($authTypes->hasNext()) {
            $authType =$authTypes->next();
                        
            // If they are authenticated, quit
            if ($authN->isUserAuthenticated($authType)) {
                return TRUE;
            }
        }
        
        return FALSE;
    }
    
    /**
     * Loop through the authentication types and try to authenticate the user.
     * 
     * @return void 
     * @access public
     * @since 8/4/06
     */
    function authenticate () {
        $authN = Services::getService("AuthN");
        
        // Reconfigure the AuthNManager to use HTTP Auth rather than forms
        // :: Start the AuthenticationManager OSID Impl.
        $configuration = new ConfigurationProperties;
        $tokenCollectors = array();
        $authNTypes =$authN->getAuthenticationTypes();
        while ($authNTypes->hasNext()) {
            $tokenCollectors[serialize($authNTypes->next())] = 
                new HTTPAuthNamePassTokenCollector($this->getRelm(),
                    $this->getCancelFunction());
        }
        $configuration->addProperty('token_collectors', $tokenCollectors);
        $authN->assignConfiguration($configuration);
        
        
        // Authenticate with HTTP Authentication.
        $harmoni = Harmoni::instance();
        $isAuthenticated = FALSE;
        $authTypes =$authN->getAuthenticationTypes();
        while ($authTypes->hasNext() && !$isAuthenticated) {
            $authType =$authTypes->next();
            
            // Try authenticating with this type
            $authN->authenticateUser($authType);
            
            // If they are authenticated, quit
            if ($authN->isUserAuthenticated($authType)) {
                $isAuthenticated = TRUE;
            }
        }
    }
    
    /**
     * Check Authorizations
     * 
     * @return boolean 
     * @access public
     * @since 8/4/06
     */
    function isExecutionAuthorized () {
        throwError(new Error(__CLASS__."::".__FUNCTION__."() must be overridded in child classes."));
    }
    
    /**
     * Answer the HTTP Authentication 'Relm' to present to the user for authentication.
     * 
     * @return mixed string or null
     * @access public
     * @since 8/7/06
     */
    function getRelm () {
        return null; // Override for custom relm.
    }
    
    /**
     * Answer the cancel function for this action, to use if the user hits
     * the 'cancel' button in the http authentication dialog.
     * 
     * @return mixed string or null
     * @access public
     * @since 8/7/06
     */
    function getCancelFunction () {
        return null; // Override for custom functions.
    }
}
 
?>