symfony 2 Updating color schemes dynamically - css

Question

I'm working in a project using Symfony 2,
I'm using Assetic with rewrite and less filter, and it work fine,
Now I'm planing to let administrator (connected user) to controle some features in css like font and main color.
The problem that I'm facing is :
- how can I proceed to integrate these css changes from entity to the css management
I can't let assetic use routing rule to include custom css
Eaven if I success to get this work, every time I have a changes to the custom css I have to install assets to web folder and make the assetic:dump and clearing cache from a controller.

Answer 1

If you (or someone else) still need this:
I solved this by putting all generic CSS in a asset handled by Assetic like usual and putting the dynamic CSS generation in a Controller action and rendering the CSS with Twig.

Answer 2

As suggested by Steffen you should put the dynamic CSS in a Twig template.
But now you might suffer from that part of the css being a full request to a symfony application instead of a css (HTTP 302 and such) which increases server load.
Thats why I would advise you to do 3 things (you can skip step 2 if your css doesn't change without interaction, e.g. date based):
Implement a service which caches the current output to e.g. web/additional.css.
Write and register a RequestListener to update the css regularly
Extend all controller actions that could introduce changes to the css with the service call
Example (assumes you use Doctrine and have an entity with some color information):
Service
<?php
//Acme\DemoBundle\Service\CSSDeployer.php
namespace Acme\DemoBundle\Service;
use Doctrine\ORM\EntityManager;
class CSSDeployer
{
/**
* #var EntityManager
*/
protected $em;
/**
* Twig Templating Service
*/
protected $templating;
public function __construct(EntityManager $em, $templating)
{
$this->em = $em;
$this->templating = $templating;
}
public function deployStyle($filepath)
{
$entity = $this->em->getRepository('AcmeDemoBundle:Color')->findBy(/* your own logic here */);
if(!$entity) {
// your error handling
}
if(!file_exists($filepath)) {
// your error handling, be aware of the case where this service is run the first time though
}
$content = $this->templating->render('AcmeDemoBundle:CSS:additional.css.twig', array(
'data' => $entity
));
//Maybe you need to wrap below in a try-catch block
file_put_contents($filepath, $content);
}
}
Service Registration
#Acme\DemoBundle\Resources\config\services.yml
services:
#...
css_deployer:
class: Acme\DemoBundle\Service\CSSDeployer
arguments: [ #doctrine.orm.entity_manager, #templating ]
RequestListener
<?php
//Acme\DemoBundle\EventListener\RequestListener.php
namespace Acme\DemoBundle\EventListener;
use Symfony\Component\HttpKernel\Event\GetResponseEvent;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\Debug\Exception\ContextErrorException;
use \DateTime;
use Doctrine\ORM\EntityManager;
class RequestListener
{
/**
* #var ContainerInterface
*/
protected $container;
/**
* #var EntityManager
*/
protected $em;
public function __construct(ContainerInterface $container, $em)
{
$this->container = $container;
$this->em = $em;
}
/**
* Checks filemtime (File modification time) of web/additional.css
* If it is not from today it will be redeployed.
*/
public function onKernelRequest(GetResponseEvent $event)
{
$kernel = $event->getKernel();
$container = $this->container;
$path = $container->get('kernel')->getRootDir().'/../web'.'/additional.css';
$time = 1300000000;
try {
$time = #filemtime($path);
} catch(ContextErrorException $ex) {
//Ignore
} catch(\Exception $ex) {
//will never get here
if(in_array($container->getParameter("kernel.environment"), array("dev","test"))) {
throw $ex;
}
}
if($time === FALSE || $time == 1300000000) {
file_put_contents($path, "/*Leer*/");
$time = 1300000000;
}
$modified = new \DateTime();
$modified->setTimestamp($time);
$today = new \DateTime();
if($modified->format("Y-m-d")!= $today->format("Y-m-d")) {
//UPDATE CSS
try {
$container->get('css_deployer')->deployStyle($path);
} catch(\Exception $ex) {
if(in_array($container->getParameter("kernel.environment"), array("dev","test"))){
throw $ex;
}
}
} else {
//DO NOTHING
}
}
}
RequestListener registration
#Acme\DemoBundle\Resources\config\services.yml
acme_style_update_listener.request:
class: Acme\DemoBundle\EventListener\RequestListener
arguments: [ #service_container, #doctrine.orm.entity_manager ]
tags:
- { name: kernel.event_listener, event: kernel.request, method: onKernelRequest }
Controller actions
public function updateAction()
{
// Stuff
$path = '....';
$this->get('css_deployer')->deployStyle($path);
}
Hope this helps someone in the future.