Architecture Overview

Alfa Commerce is a Joomla 6/7 component made of three applications that share one database and one service layer:

Application	Path	Does
Site	site/	The storefront — catalog, cart, checkout
Administrator	administrator/	Catalog, orders, settings, the bulk of the code
API	api/	A JSON-API (Postman collection)

Business logic lives in helpers & services (not controllers), prices are immutable value objects, and third parties extend the system through events — never by editing core.

The big picture

The three applications run the same Joomla MVC; controllers stay thin and delegate to the service layer; and at well defined points the component dispatches events that plugins handle.

Request flow

Same path for all three apps — the API simply ends in a JSON view instead of an HTML template, and the admin adds Form XML + Table CRUD.

Service layer

Controllers orchestrate; the real work is in helpers/services so it can be reused by the site, admin and API alike:

• Cart & checkout — CartHelper, OrderPlaceHelper (atomic, transactional order placement)
• Orders — Order Helpers (items, totals, stock, statuses)
• Pricing — the Pricing engine + PriceIndexSyncService

Plugins & events

The component boots plugins by group and dispatches typed events to them; a plugin's capability is set by the event class it receives (data → redirect → layout). See Plugin Development. Groups: alfa-payments, alfa-shipments, alfa-form-fields, alfa-media, plus the webservices and system plugins.

Dependency injection

administrator/services/provider.php registers the component's factories and the component itself:

$container->registerServiceProvider(new MVCFactory('\\Alfa\\Component\\Alfa'));
$container->registerServiceProvider(new ComponentDispatcherFactory('\\Alfa\\Component\\Alfa'));
$container->registerServiceProvider(new RouterFactory('\\Alfa\\Component\\Alfa'));

// Frontend language-switch associations (mod_languages / languagefilter)
$container->set(AssociationExtensionInterface::class, new AssociationsHelper());

// The component, wired with the registry, MVC factory, router and associations
$container->set(ComponentInterface::class, fn ($c) => (new AlfaComponent(
    $c->get(ComponentDispatcherFactoryInterface::class)
))->setRegistry(...)->setMVCFactory(...)->setRouterFactory(...)->setAssociationExtension(...));

Patterns at a glance

Pattern	Where
MVC	every controller / model / view
Service layer	CartHelper, OrderPlaceHelper, the order helpers, PriceIndexSyncService
Value objects (immutable)	Money, Currency, PriceResult
Fluent builders	OrderPaymentHelper, OrderShipmentHelper, PriceSettings
Strategy	PricingIntent (catalog / cart / checkout / quote)
Observer / events	the plugin system