Back-Office Development

The Thelia 3 back-office (admin panel) is a Symfony bundle named default-twig. It renders Twig templates, fetches data through Repositories, and displays lists with Twig UiComponents (a server-rendered DataTable). Modules extend it through hooks and Symfony UX (Stimulus plus LiveComponent/TwigComponent).

The bundle lives at templates/backOffice/default-twig/. It declares its own routes with PHP 8 #[Route] attributes, along with its own hooks, templates, forms, and assets.

The Smarty back-office is legacy

The previous Smarty default back-office theme is no longer recommended and will likely be dropped in Thelia 3.1. New development targets the default-twig bundle. The two themes can run side by side during the transition, but build any new admin screen on the Twig bundle.

Back-office vs front-office

Aspect	Back-office (default-twig)	Front-office (Flexy)
Template engine	Twig	Twig
Data access	Repositories plus Twig UiComponents (DataTable)	DataAccessService (API)
Extensibility	Hooks (safe_hook, hook_block, has_hook Twig functions) plus #[AsHook]	Hooks plus Twig overrides
Interactivity	Stimulus plus Symfony UX (LiveComponent / TwigComponent)	Stimulus plus Symfony UX

Activating the Twig back-office

The default-twig bundle is the back-office reference. Activate it at install time, or switch an existing installation over to it.

# fresh install - select the default-twig back-office theme
ddev exec php bin/install \
  --frontoffice_theme=flexy --backoffice_theme=default-twig \
  --pdf_theme=default --email_theme=default \
  --with-demo --with-admin \
  --admin_login=thelia --admin_password=thelia \
  --admin_first_name=thelia --admin_last_name=thelia \
  --admin_email=thelia@example.com

# already installed - switch the active back-office template
ddev exec bin/console template:set backOffice default-twig
ddev exec bin/console cache:warmup -e dev

# build the bundle assets (SCSS + JS)
ddev exec bash -c "cd templates/backOffice/default-twig && npm install && npm run build"

The admin is then available at https://<your-site>.ddev.site/admin.

Watch assets during development

While editing SCSS or Stimulus controllers, run npm run watch from templates/backOffice/default-twig/ so the bundle assets rebuild automatically. After editing a Twig template, clear the cache with ddev exec bin/console cache:clear -e dev.

Bundle structure

The back-office is a regular Symfony bundle. Templates live at the bundle root (so the Thelia parser resolver picks them up as templates/backOffice/default-twig/<name>.html.twig), and the PHP lives under src/:

templates/backOffice/default-twig/
├── base.html.twig             # base layout
├── auth-layout.html.twig      # login screen
├── home.html.twig             # dashboard
├── <domain>/                  # one folder per business domain (catalog, customer, order, ...)
│   ├── list.html.twig
│   ├── edit.html.twig
│   ├── _create_modal.html.twig
│   └── _delete_modal.html.twig
├── components/                # reusable Twig component templates (DataTable, Dashboard, ...)
├── form/
│   └── bo_form_theme.html.twig    # Bootstrap 5 form theme, scoped to /admin
├── config/
│   └── packages/twig.yaml         # registers the form theme namespace + form_themes
├── assets/                    # SCSS + JS + img + flags
│   ├── app.js
│   ├── controllers/           # Stimulus controllers
│   └── styles/
└── src/
    ├── BackOfficeDefaultTwigBundle.php
    ├── Controller/            # one folder per domain (Catalog, Customer, Order, ...)
    ├── DTO/                   # immutable data transfer objects
    ├── EventListener/         # AdminContextRequestListener, AdminLocaleListener
    ├── Form/                  # Symfony form types (CustomerType, AddressType, ...)
    ├── Hook/Attribute/        # the #[AsHook] attribute
    ├── Repository/            # Propel queries
    ├── Security/              # AdminVoter
    ├── Service/               # back-office services (AdminFormAction, ...)
    ├── Twig/                  # Twig extensions (HookExtension, DataTableExtension, ...)
    └── UiComponents/          # AsTwigComponent / AsLiveComponent

The bundle is registered as a standard Symfony bundle and only loads its services when it is the active back-office template. Services are autodiscovered and autoconfigured, so there is no service XML to write:

// templates/backOffice/default-twig/src/BackOfficeDefaultTwigBundle.php
$container->services()
    ->load('BackOfficeDefaultTwigBundle\\', $resourcePath)
    ->exclude([
        $resourcePath.'/BackOfficeDefaultTwigBundle.php',
        $resourcePath.'/DTO/',
        $resourcePath.'/Hook/Attribute/',
        $resourcePath.'/DependencyInjection/',
    ])
    ->autowire()
    ->autoconfigure();

Adding an admin page from a module

A module adds an admin page with a thin controller and a PHP 8 #[Route] attribute. The controller renders a Twig template; it never persists data itself. Thelia is event-driven: Controller → dispatch(Event) → Action listener → Model::save().

// local/modules/MyModule/src/Controller/ConfigController.php
namespace MyModule\Controller;

use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\Routing\Attribute\Route;
use Twig\Environment;

final class ConfigController
{
    public function __construct(private readonly Environment $twig)
    {
    }

    #[Route('/admin/module/MyModule', name: 'mymodule.admin.config')]
    public function config(): Response
    {
        return new Response($this->twig->render('@MyModule/config.html.twig'));
    }
}

No @Route annotations

Symfony 7 removed Doctrine annotations. Always use the PHP 8 attribute Symfony\Component\Routing\Attribute\Route, never @Route.

Back-office forms

Build admin forms with Symfony's form component and let the bundle's bo_form_theme.html.twig render them with Bootstrap 5 markup. The theme is registered globally and scopes itself to the /admin path, so any form rendered under /admin gets the back-office styling automatically.

// local/modules/MyModule/src/Form/ConfigType.php
namespace MyModule\Form;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\Extension\Core\Type\CheckboxType;
use Symfony\Component\Form\Extension\Core\Type\TextType;
use Symfony\Component\Form\FormBuilderInterface;

final class ConfigType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options): void
    {
        $builder
            ->add('apiKey', TextType::class, [
                'label' => 'API key',
                'required' => true,
            ])
            ->add('enabled', CheckboxType::class, [
                'label' => 'Enable module',
                'required' => false,
            ]);
    }
}

Render the form in a Twig template with the standard Symfony form helpers:

{# local/modules/MyModule/templates/config.html.twig #}
{{ form_start(form, { action: path('mymodule.admin.config.save'), method: 'post' }) }}
    {{ form_row(form.apiKey) }}
    {{ form_row(form.enabled) }}
    <button type="submit" class="btn btn-primary">{{ 'Save'|trans }}</button>
{{ form_end(form) }}

The form theme is wired in the bundle's Twig configuration:

# templates/backOffice/default-twig/config/packages/twig.yaml
twig:
  paths:
    "%kernel.project_dir%/templates/backOffice/default-twig/form": BackOfficeDefaultTwigForm
  form_themes:
    - "@BackOfficeDefaultTwigForm/bo_form_theme.html.twig"

Extending the back-office with hooks

Hooks are the extension points modules use to inject content into back-office screens. In templates, the bundle exposes Twig functions through BackOfficeDefaultTwigBundle\Twig\HookExtension:

{# render a hook's HTML output (tolerant: swallows a failing listener) #}
{{ safe_hook('state.edit-js', { state_id: state.id }) }}

{# iterate over the fragments contributed by a block hook #}
{% if has_hook('product.tab') %}
    <ul>
        {% for block in hook_block('product.tab', { product_id: product.id }) %}
            <li><a href="{{ block.href }}">{{ block.title }}</a></li>
        {% endfor %}
    </ul>
{% endif %}

On the module side, a hook listener extends Thelia\Core\Hook\BaseHook and declares which hooks it listens to with getSubscribedHooks():

// local/modules/MyModule/src/Hook/AdminHook.php
namespace MyModule\Hook;

use Thelia\Core\Event\Hook\HookRenderBlockEvent;
use Thelia\Core\Event\Hook\HookRenderEvent;
use Thelia\Core\Hook\BaseHook;
use Thelia\Tools\URL;

final class AdminHook extends BaseHook
{
    public static function getSubscribedHooks(): array
    {
        return [
            'main.top-menu-tools' => [
                ['type' => 'back', 'method' => 'onMainTopMenuTools'],
            ],
            'product.tab' => [
                ['type' => 'back', 'method' => 'onProductTab'],
            ],
        ];
    }

    public function onMainTopMenuTools(HookRenderBlockEvent $event): void
    {
        $event->add([
            'id' => 'mymodule-menu',
            'title' => $this->trans('My Module'),
            'href' => URL::getInstance()->absoluteUrl('/admin/module/MyModule'),
        ]);
    }

    public function onProductTab(HookRenderEvent $event): void
    {
        $productId = $event->getArgument('product_id');

        $event->add($this->render('product-tab.html', ['product_id' => $productId]));
    }
}

Attribute alternative: #[AsHook]

The Twig back-office also ships a PHP 8 attribute, BackOfficeDefaultTwigBundle\Hook\Attribute\AsHook, registered for autoconfiguration by the bundle. You can annotate a listener method instead of returning a getSubscribedHooks() array:

use BackOfficeDefaultTwigBundle\Hook\Attribute\AsHook;
use Thelia\Core\Event\Hook\HookRenderEvent;

#[AsHook(event: 'product.tab', type: 'back')]
public function onProductTab(HookRenderEvent $event): void
{
    // ...
}

The attribute takes event (the hook code), an optional type (defaults to back), and an optional priority.

See the Hooks Reference for the full list of back-office hooks and the conventional extension points every screen emits.

Interactivity: Stimulus and Symfony UX

The back-office uses Symfony UX:

• Stimulus controllers live in assets/controllers/ and wire behavior to markup with data-controller / data-action attributes.
• TwigComponent and LiveComponent classes live in src/UiComponents/ (annotated with #[AsTwigComponent] / #[AsLiveComponent]). The list screens render through a server-side DataTable component.

There is no separate jQuery layer to learn. The same UX stack powers both the front-office Flexy theme and the back-office bundle.

Best practices

Do

• Build new admin screens on the default-twig bundle, not the Smarty theme.
• Keep controllers thin: dispatch an event and let an Action listener persist.
• Fetch data through Repositories and present lists with the DataTable UiComponent.
• Use hooks (safe_hook / hook_block) to extend existing screens instead of editing core templates.
• Render forms with the bo_form_theme so they match the rest of the admin.
• Translate every user-facing string with |trans.

Don't

• Don't edit core back-office templates directly; extend through hooks.
• Don't use @Route annotations; use the PHP 8 #[Route] attribute.
• Don't call save() from a controller; dispatch an event instead, since Thelia is event-driven.
• Don't hardcode URLs; use path() / url().
• Don't skip the CSRF token on form submissions.

Reference documentation

• Hooks Reference: all back-office hooks and conventional extension points
• Forms: Thelia form handling
• Internationalization: translating admin strings
• Module Development: creating modules

Next steps

• Hooks: extend the admin interface through hooks
• Module controllers: add admin pages from a module
• Front-office LiveComponents: the Symfony UX patterns reused by the back-office