integrate-a-css-preprocessor.md

Integrate a CSS preprocessor

To integrate a preprocessor you can use the \bitboxde\minifier\services\View::EVENT_BEFORE_MINIFY_FILE event in your Plugin. This event will only fired if a file has changed. We used for this example the simple repository of leafo/lessphp, but you can use any preprocessor. Just compile the file and set the result in the output property of the ViewEvent.

Event::on(
    \bitboxde\minifier\services\View::class,
    \bitboxde\minifier\services\View::EVENT_BEFORE_MINIFY_FILE,
    function(\bitboxde\minifier\events\ViewEvent $event) {
        $pathinfo = pathinfo($event->filePath);
        $ext = $pathinfo['extension'];

        if($ext === 'less') {
            $parser = new \lessc();
            $event->output = $parser->compileFile($event->filePath);
        }
    }
);