* @link http://www.yiiframework.com/
* @copyright 2008-2013 Yii Software LLC
* @license http://www.yiiframework.com/license/
*/
/**
* CDbMessageSource represents a message source that stores translated messages in database.
*
* The database must contain the following two tables:
*
* CREATE TABLE SourceMessage
* (
* id INTEGER PRIMARY KEY,
* category VARCHAR(32),
* message TEXT
* );
* CREATE TABLE Message
* (
* id INTEGER,
* language VARCHAR(16),
* translation TEXT,
* PRIMARY KEY (id, language),
* CONSTRAINT FK_Message_SourceMessage FOREIGN KEY (id)
* REFERENCES SourceMessage (id) ON DELETE CASCADE ON UPDATE RESTRICT
* );
*
* The 'SourceMessage' table stores the messages to be translated, and the 'Message' table
* stores the translated messages. The name of these two tables can be customized by setting
* {@link sourceMessageTable} and {@link translatedMessageTable}, respectively.
*
* When {@link cachingDuration} is set as a positive number, message translations will be cached.
*
* @property CDbConnection $dbConnection The DB connection used for the message source.
*
* @author Qiang Xue
* @package system.i18n
* @since 1.0
*/
class CDbMessageSource extends CMessageSource
{
const CACHE_KEY_PREFIX='Yii.CDbMessageSource.';
/**
* @var string the ID of the database connection application component. Defaults to 'db'.
*/
public $connectionID='db';
/**
* @var string the name of the source message table. Defaults to 'SourceMessage'.
*/
public $sourceMessageTable='SourceMessage';
/**
* @var string the name of the translated message table. Defaults to 'Message'.
*/
public $translatedMessageTable='Message';
/**
* @var integer the time in seconds that the messages can remain valid in cache.
* Defaults to 0, meaning the caching is disabled.
*/
public $cachingDuration=0;
/**
* @var string the ID of the cache application component that is used to cache the messages.
* Defaults to 'cache' which refers to the primary cache application component.
* Set this property to false if you want to disable caching the messages.
*/
public $cacheID='cache';
/**
* Loads the message translation for the specified language and category.
* @param string $category the message category
* @param string $language the target language
* @return array the loaded messages
*/
protected function loadMessages($category,$language)
{
if($this->cachingDuration>0 && $this->cacheID!==false && ($cache=Yii::app()->getComponent($this->cacheID))!==null)
{
$key=self::CACHE_KEY_PREFIX.'.messages.'.$category.'.'.$language;
if(($data=$cache->get($key))!==false)
return unserialize($data);
}
$messages=$this->loadMessagesFromDb($category,$language);
if(isset($cache))
$cache->set($key,serialize($messages),$this->cachingDuration);
return $messages;
}
private $_db;
/**
* Returns the DB connection used for the message source.
* @throws CException if {@link connectionID} application component is invalid
* @return CDbConnection the DB connection used for the message source.
* @since 1.1.5
*/
public function getDbConnection()
{
if($this->_db===null)
{
$this->_db=Yii::app()->getComponent($this->connectionID);
if(!$this->_db instanceof CDbConnection)
throw new CException(Yii::t('yii','CDbMessageSource.connectionID is invalid. Please make sure "{id}" refers to a valid database application component.',
array('{id}'=>$this->connectionID)));
}
return $this->_db;
}
/**
* Loads the messages from database.
* You may override this method to customize the message storage in the database.
* @param string $category the message category
* @param string $language the target language
* @return array the messages loaded from database
* @since 1.1.5
*/
protected function loadMessagesFromDb($category,$language)
{
$sql=<<sourceMessageTable} t1, {$this->translatedMessageTable} t2
WHERE t1.id=t2.id AND t1.category=:category AND t2.language=:language
EOD;
$command=$this->getDbConnection()->createCommand($sql);
$command->bindValue(':category',$category);
$command->bindValue(':language',$language);
$messages=array();
foreach($command->queryAll() as $row)
$messages[$row['message']]=$row['translation'];
return $messages;
}
}