How to Minify JavaScripts and Stylesheets with YUI Compressor¶
Yahoo! provides an excellent utility for minifying JavaScripts and stylesheets so they travel over the wire faster, the YUI Compressor. Thanks to Assetic, you can take advantage of this tool very easily.
Download the YUI Compressor JAR¶
The YUI Compressor is written in Java and distributed as a JAR. Download the JAR
from the Yahoo! site and save it to app/Resources/java/yuicompressor.jar
.
Configure the YUI Filters¶
Now you need to configure two Assetic filters in your application, one for minifying JavaScripts with the YUI Compressor and one for minifying stylesheets:
- YAML
# app/config/config.yml assetic: filters: yui_css: jar: "%kernel.root_dir%/Resources/java/yuicompressor.jar" yui_js: jar: "%kernel.root_dir%/Resources/java/yuicompressor.jar"
- XML
<!-- app/config/config.xml --> <assetic:config> <assetic:filter name="yui_css" jar="%kernel.root_dir%/Resources/java/yuicompressor.jar" /> <assetic:filter name="yui_js" jar="%kernel.root_dir%/Resources/java/yuicompressor.jar" /> </assetic:config>
- PHP
// app/config/config.php $container->loadFromExtension('assetic', array( 'filters' => array( 'yui_css' => array( 'jar' => '%kernel.root_dir%/Resources/java/yuicompressor.jar', ), 'yui_js' => array( 'jar' => '%kernel.root_dir%/Resources/java/yuicompressor.jar', ), ), ));
You now have access to two new Assetic filters in your application:
yui_css
and yui_js
. These will use the YUI Compressor to minify
stylesheets and JavaScripts, respectively.
Minify your Assets¶
You have YUI Compressor configured now, but nothing is going to happen until you apply one of these filters to an asset. Since your assets are a part of the view layer, this work is done in your templates:
- Twig
{% javascripts '@AcmeFooBundle/Resources/public/js/*' filter='yui_js' %} <script src="{{ asset_url }}"></script> {% endjavascripts %}
- PHP
<?php foreach ($view['assetic']->javascripts( array('@AcmeFooBundle/Resources/public/js/*'), array('yui_js')) as $url): ?> <script src="<?php echo $view->escape($url) ?>"></script> <?php endforeach; ?>
Note
The above example assumes that you have a bundle called AcmeFooBundle
and your JavaScript files are in the Resources/public/js
directory under
your bundle. This isn’t important however - you can include your Javascript
files no matter where they are.
With the addition of the yui_js
filter to the asset tags above, you should
now see minified JavaScripts coming over the wire much faster. The same process
can be repeated to minify your stylesheets.
- Twig
{% stylesheets '@AcmeFooBundle/Resources/public/css/*' filter='yui_css' %} <link rel="stylesheet" type="text/css" media="screen" href="{{ asset_url }}" /> {% endstylesheets %}
- PHP
<?php foreach ($view['assetic']->stylesheets( array('@AcmeFooBundle/Resources/public/css/*'), array('yui_css')) as $url): ?> <link rel="stylesheet" type="text/css" media="screen" href="<?php echo $view->escape($url) ?>" /> <?php endforeach; ?>
Disable Minification in Debug Mode¶
Minified JavaScripts and Stylesheets are very difficult to read, let alone
debug. Because of this, Assetic lets you disable a certain filter when your
application is in debug mode. You can do this be prefixing the filter name
in your template with a question mark: ?
. This tells Assetic to only
apply this filter when debug mode is off.
- Twig
{% javascripts '@AcmeFooBundle/Resources/public/js/*' filter='?yui_js' %} <script src="{{ asset_url }}"></script> {% endjavascripts %}
- PHP
<?php foreach ($view['assetic']->javascripts( array('@AcmeFooBundle/Resources/public/js/*'), array('?yui_js')) as $url): ?> <script src="<?php echo $view->escape($url) ?>"></script> <?php endforeach; ?>