Style Backend Depending on the Application Environment

Sometimes it makes sense to style the OpenDxp backend UI depending on the application environment (APP_ENV) so that backend users can easily differentiate by the looks.

Imagine having additional environments for Staging and Testing and you want to give editors a hint that they are working in the correct environment.

This can be easily implemented as the backend's body element contains a data attribute data-app-env with the current application environment (e.g. <body class="opendxp_version_1" data-app-env="dev">) and thus can be referenced with a CSS selector.

Backend UI style override

Add an event subscriber

services:
    # Event subscribers
    App\EventSubscriber\:
        resource: '../src/EventSubscriber/*'
        tags: [ 'kernel.event_subscriber' ]

And subscribe to \OpenDxp\Bundle\AdminBundle\Event\BundleManagerEvents::CSS_PATHS event in order to load a custom CSS file (e.g. /css/env.css).

<?php

namespace App\EventSubscriber;

class AdminAssetsSubscriber implements \Symfony\Component\EventDispatcher\EventSubscriberInterface
{
    public static function getSubscribedEvents(): array
    {
        return [
            \OpenDxp\Bundle\AdminBundle\Event\BundleManagerEvents::CSS_PATHS => 'onCssPaths',
        ];
    }

    public function onCssPaths(\OpenDxp\Event\BundleManager\PathsEvent $event): void
    {
        $event->addPaths(['/css/env.css']);
    }
}

Create a CSS file /css/env.css. In this example, we intentionally style the OpenDxp backend's UI body with a standout background.

body:not([data-app-env='prod']) #opendxp_body {
    background: repeating-linear-gradient(
        -45deg,
        #005baa,
        #005baa 5px,
        #0c0f12 30px,
        #0c0f12 10px
    );
}