Subversion-Projekte lars-tiefland.prado

<?php
/**
 * TJsonService and TJsonResponse class file.
 *
 * @author Wei Zhuo <weizhuo[at]gamil[dot]com>
 * @link http://www.pradosoft.com/
 * @copyright Copyright &copy; 2005-2008 PradoSoft
 * @license http://www.pradosoft.com/license/
 * @version $Id: TJsonService.php 2574 2008-11-30 23:09:51Z carlgmathisen $
 * @package System.Web.Services
 */

/**
 * TJsonService class provides to end-users javascript content response in
 * JSON format.
 *
 * TJsonService manages a set of {@link TJsonResponse}, each
 * representing specific response with javascript content.
 * The service parameter, referring to the ID of the service, specifies
 * which javascript content to be provided to end-users.
 *
 * To use TJsonService, configure it in application configuration as follows,
 * <code>
 *  <service id="json" class="System.Web.Services.TJsonService">
 *    <json id="get_article" class="Path.To.JsonResponseClass1" .../>
 *    <json id="register_rating" class="Path.To.JsonResponseClass2" .../>
 *  </service>
 * </code>
 * where each JSON response is specified via a &lt;json&gt; element.
 * Initial property values can be configured in a &lt;json&gt; element.
 *
 * To retrieve the JSON content provided by "get_article", use the URL
 * <code>index.php?json=get_article</code>
 *
 * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
 * @version $Id: TJsonService.php 2574 2008-11-30 23:09:51Z carlgmathisen $
 * @package System.Web.Services
 * @since 3.1
 */
class TJsonService extends TService
{
        /**
         * @var array registered services
         */
        private $_services=array();

        /**
         * Initializes this module.
         * This method is required by the IModule interface.
         * @param TXmlElement configuration for this module, can be null
         */
        public function init($xml)
        {
                $this->loadJsonServices($xml);
        }

        /**
         * Load the service definitions.
         * @param TXmlElement configuration for this module, can be null
         */
        protected function loadJsonServices($xml)
        {
                foreach($xml->getElementsByTagName('json') as $config)
                {
                        if(($id=$config->getAttribute('id'))!==null)
                                $this->_services[$id]=$config;
                        else
                                throw new TConfigurationException('jsonservice_id_required');
                }
        }

        /**
         * Runs the service.
         * This method is invoked by application automatically.
         */
        public function run()
        {
                $id=$this->getRequest()->getServiceParameter();
                if(isset($this->_services[$id]))
                {
                        $serviceConfig=$this->_services[$id];
                        $properties=$serviceConfig->getAttributes();
                        if(($class=$properties->remove('class'))!==null)
                        {
                                $service=Prado::createComponent($class);
                                if($service instanceof TJsonResponse)
                                        $this->createJsonResponse($service,$properties,$serviceConfig);
                                else
                                        throw new TConfigurationException('jsonservice_response_type_invalid',$id);
                        }
                        else
                                throw new TConfigurationException('jsonservice_class_required',$id);
                }
                else
                        throw new THttpException(404,'jsonservice_provider_unknown',$id);
        }

        /**
         * Renders content provided by TJsonResponse::getJsonContent() as
         * javascript in JSON format.
         */
        protected function createJsonResponse($service,$properties,$config)
        {
                // init service properties
                foreach($properties as $name=>$value)
                        $service->setSubproperty($name,$value);
                $service->init($config);

                //send content if not null
                if(($content=$service->getJsonContent())!==null)
                {
                        $response = $this->getResponse();
                        $response->setContentType('text/javascript');
                        $response->setCharset('UTF-8');
                        $json = Prado::createComponent('System.Web.Javascripts.TJSON');

                        //send content
                        $response->write($json->encode($content));
                }
        }
}

/**
 * TJsonResponse Class
 *
 * TJsonResponse is the base class for all JSON response provider classes.
 *
 * Derived classes must implement {@link getJsonContent()} to return
 * an object or literals to be converted to JSON format. The response
 * will be empty if the returned content is null.
 *
 * @author Wei Zhuo <weizhuo[at]gmail[dot]com>
 * @version $Id: TJsonService.php 2574 2008-11-30 23:09:51Z carlgmathisen $
 * @package System.Web.Services
 * @since 3.1
 */
abstract class TJsonResponse extends TApplicationComponent
{
        private $_id='';

        /**
         * Initializes the feed.
         * @param TXmlElement configurations specified in {@link TJsonService}.
         */
        public function init($config)
        {
        }

        /**
         * @return string ID of this response
         */
        public function getID()
        {
                return $this->_id;
        }

        /**
         * @param string ID of this response
         */
        public function setID($value)
        {
                $this->_id=$value;
        }

        /**
         * @return object json response content, null to suppress output.
         */
        abstract public function getJsonContent();
}

?>