tips-and-tricks.md

Tips and Tricks

Improving Backend Performance

EasyAdmin does an intense use of Doctrine metadata introspection to generate the backend on the fly without generating any file or resource. For complex backends, this process can add a noticeable performance overhead.

Fortunately, Doctrine provides a simple caching mechanism for entity metadata. If your server has APC installed, enable this cache just by adding the following configuration:

# app/config/config_prod.yml
doctrine:
    orm:
        metadata_cache_driver: apc

In addition to apc, Doctrine metadata cache supports memcache, memcached, xcache and service (for using a custom cache service). Read the documentation about Doctrine caching drivers.

Note that the previous example configures metadata caching in config_prod.yml file, which is the configuration used for the production environment. It's not recommended to enable this cache in the development environment to avoid having to clear APC cache or restart the web server whenever you make any change to your Doctrine entities.

This simple metadata cache configuration can improve your backend performance between 20% and 30% depending on the complexity and number of your entities.

Create a Read-Only Backend

Disable the delete, edit and new actions for all views and the users won't be able to add, modify or remove any information:

easy_admin:
    disabled_actions: ['delete', 'edit', 'new']

Unloading the Default JavaScript and Stylesheets

EasyAdmin uses Bootstrap CSS and jQuery frameworks to build the interface. In case you want to unload these files in addition to loading your own assets, override the default layout.html.twig template and empty the head_stylesheets and head_javascript Twig blocks.

Read the Advanced Design Customization section to learn how to override default templates.

Removing Action Labels and Displaying Just Icons

By default, the actions showed in the list view table only display their label (Edit, Show, etc.):

Adding an icon for each action is as easy as defining their icon option:

easy_admin:
    list:
        actions:
            - { name: 'show', icon: 'search' }
            - { name: 'edit', icon: 'pencil' }
    # ...

This configuration makes the entity listing looks as follow:

When displaying entities with lots of information, it may be useful to remove the action label and display just their icons. To do so, define an empty string for the label option or set its value to false:

easy_admin:
    list:
        actions:
            - { name: 'show', icon: 'search', label: '' }
            - { name: 'edit', icon: 'pencil', label: '' }
            # if you prefer, set labels to false
            # - { name: 'show', icon: 'search', label: false }
            # - { name: 'edit', icon: 'pencil', label: false }
    # ...

This configuration makes the entity listing looks as follow:

Making the Backend Use a Different Language Than the Public Website

Imagine that the public part of your website uses French as its default locale. EasyAdmin uses the same locale as the underlying Symfony application, so the backend would be displayed in French too. How could you define a different language for the backend?

You just need to get the translator service and execute the setLocale() method befor executing the code of EasyAdmin. The easiest way to do that is to create a custom admin controller and override the initialize() method as follows:

// src/AppBundle/Controller/AdminController.php
namespace AppBundle\Controller;

use JavierEguiluz\Bundle\EasyAdminBundle\Controller\AdminController as BaseAdminController;

class AdminController extends BaseAdminController
{
    protected function initialize(Request $request)
    {
        $this->get('translator')->setLocale('en');
        parent::initialize($request);
    }
}

Don't Apply Global Doctrine Filters in the Backend

Doctrine filters add conditions to your queries automatically. They are useful to solve cases like "never display products which haven't been published" or "don't display comments marked as deleted".

These filters can be enabled for each query, but they are usually enabled globally for the entire application thanks to a request listener:

use Symfony\Component\HttpKernel\Event\GetResponseEvent;

class DoctrineFilterListener
{
    // ...

    public function onKernelRequest(GetResponseEvent $event)
    {
        $this->em->getFilters()->enable('is_published');
    }
}

When using global Doctrine filters, you probably don't want to apply them in the backend. Otherwise you won't see unpublished items or deleted comments in the listings. Given that all EasyAdmin URLs are generated with a single route called easyadmin, you can add the following to disable the Doctrine filters in the backend:

public function onKernelRequest(GetResponseEvent $event)
{
    if ('easyadmin' === $event->getRequest()->attributes->get('_route')) {
        return;
    }

    // ...
}

Defining Dynamic Actions per Item

By default, in the list view all items display the same actions. If you need to show/hide actions dynamically per item, you can do that in a custom template. Consider a backend that displays the Delete action only for items that haven't been published yet (their status property is PUBLISHED):

{# app/Resources/views/easy_admin/list.html.twig #}
{% extends '@EasyAdmin/default/list.html.twig' %}

{% block item_actions %}
    {% set filtered_actions = {} %}
    {% for action_name, action_config in _list_item_actions %}
        {% if action_name == 'delete' and item.status|default(false) == 'PUBLISHED' %}
            {# remove the 'delete' action from published items #}
        {% else %}
            {% set filtered_actions = filtered_actions|merge([action_config]) %}
        {% endif %}
    {% endfor %}

    {% set _list_item_actions = filtered_actions %}

    {{ parent() }}
{% endblock item_actions %}

The solution work as follows:

1. The backend defines a new list.html.twig template to override the item_actions block, which is the one that displays the actions for each item.
2. The default template defines the _list_item_actions variable to store the actions to display for any given item. The custom template just needs to filter these actions according to some rules.
3. Finally, override the original _list_item_actions variable with the filtered list of actions and execute the original code for this Twig block in the parent template ({{ parent() }}).