EMessageSource is an unified Message Sources for Yii.
Default, Yii only use one message source. Like CPhpMessageSource, CDbMessageSource or CGettextMessageSource.
This component help you scan a list of all available message source and find if it has been translated.
In your application config file:
'messages' => array(
'class' => 'ext.components.EMessageSource',
'sources' => array(
// @XXX: The first message source we should check
'phpMessage' => array(
'class' => 'CPhpMessageSource',
'onMissingTranslation' => array('CPhpMessageTranslator', 'appendMessage'),
),
// @XXX: Another MessageSource
'dbMessage' => array(
'class' => 'CDbMessageSource',
'sourceMessageTable' => 'sourcemessage',
'translatedMessageTable' => 'message',
'onMissingTranslation' => array('CDbMessageTranslator', 'appendMessage'),
),
// @XXX: Another brick in the wall
'gettextMessage' => array(
'class' => 'CGettextMessageSource',
'onMissingTranslation' => array('CGettextMessageTranslator', 'appendMessage'),
),
),
),
From now on, whenever you call Yii::t(), the application will check all the message source, then return the translation if available.
It even can write the CPhpMessageSource translation file, and write the CDbMessageTranslator message too...
So that's it.