Subversion-Projekte lars-tiefland.prado

<?php
/**
 * TParameterModule class
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link http://www.pradosoft.com/
 * @copyright Copyright &copy; 2005-2008 PradoSoft
 * @license http://www.pradosoft.com/license/
 * @version $Id: TParameterModule.php 2541 2008-10-21 15:05:13Z qiang.xue $
 * @package System.Util
 */

/**
 * TParameterModule class
 *
 * TParameterModule enables loading application parameters from external
 * storage other than the application configuration.
 * To load parameters from an XML file, configure the module by setting
 * its {@link setParameterFile ParameterFile} property.
 * Note, the property only accepts a file path in namespace format with
 * file extension being '.xml'. The file format is as follows,  which is
 * similar to the parameter portion in an application configuration,
 * <code>
 * <parameters>
 *   <parameter id="param1" value="paramValue1" />
 *   <parameter id="param2" Property1="Value1" Property2="Value2" ... />
 * </parameters>
 * </code>
 *
 * In addition, any content enclosed within the module tag is also treated
 * as parameters, e.g.,
 * <code>
 * <module class="System.Util.TParameterModule">
 *   <parameter id="param1" value="paramValue1" />
 *   <parameter id="param2" Property1="Value1" Property2="Value2" ... />
 * </module>
 * </code>
 *
 * If a parameter is defined both in the external file and within the module
 * tag, the former takes precedence.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @version $Id: TParameterModule.php 2541 2008-10-21 15:05:13Z qiang.xue $
 * @package System.Util
 * @since 3.0
 */
class TParameterModule extends TModule
{
        const PARAM_FILE_EXT='.xml';
        private $_initialized=false;
        private $_paramFile=null;

        /**
         * Initializes the module by loading parameters.
         * @param TXmlElement content enclosed within the module tag
         */
        public function init($config)
        {
                $this->loadParameters($config);
                if($this->_paramFile!==null)
                {
                        if(($cache=$this->getApplication()->getCache())!==null)
                        {
                                $cacheKey='TParameterModule:'.$this->_paramFile;
                                if(($dom=$cache->get($cacheKey))===false)
                                {
                                        $dom=new TXmlDocument;
                                        $dom->loadFromFile($this->_paramFile);
                                        $cache->set($cacheKey,$dom,0,new TFileCacheDependency($this->_paramFile));
                                }
                        }
                        else
                        {
                                $dom=new TXmlDocument;
                                $dom->loadFromFile($this->_paramFile);
                        }
                        $this->loadParameters($dom);
                }
                $this->_initialized=true;
        }

        /**
         * Loads parameters into application.
         * @param TXmlElement XML representation of the parameters
         * @throws TConfigurationException if the parameter file format is invalid
         */
        protected function loadParameters($xmlNode)
        {
                $parameters=array();
                foreach($xmlNode->getElementsByTagName('parameter') as $node)
                {
                        $properties=$node->getAttributes();
                        if(($id=$properties->remove('id'))===null)
                                throw new TConfigurationException('parametermodule_parameterid_required');
                        if(($type=$properties->remove('class'))===null)
                        {
                                if(($value=$properties->remove('value'))===null)
                                        $parameters[$id]=$node;
                                else
                                        $parameters[$id]=$value;
                        }
                        else
                                $parameters[$id]=array($type,$properties->toArray());
                }

                $appParams=$this->getApplication()->getParameters();
                foreach($parameters as $id=>$parameter)
                {
                        if(is_array($parameter))
                        {
                                $component=Prado::createComponent($parameter[0]);
                                foreach($parameter[1] as $name=>$value)
                                        $component->setSubProperty($name,$value);
                                $appParams->add($id,$component);
                        }
                        else
                                $appParams->add($id,$parameter);
                }
        }

        /**
         * @return string the parameter file path
         */
        public function getParameterFile()
        {
                return $this->_paramFile;
        }

        /**
         * @param string the parameter file path. It must be in namespace format
         * and the file extension is '.xml'.
         * @throws TInvalidOperationException if the module is initialized
         * @throws TConfigurationException if the file is invalid
         */
        public function setParameterFile($value)
        {
                if($this->_initialized)
                        throw new TInvalidOperationException('parametermodule_parameterfile_unchangeable');
                else if(($this->_paramFile=Prado::getPathOfNamespace($value,self::PARAM_FILE_EXT))===null || !is_file($this->_paramFile))
                        throw new TConfigurationException('parametermodule_parameterfile_invalid',$value);
        }
}