Facade Pattern Generator

Creates Facade pattern infrastructure for providing simplified access to complex subsystems.

When to Use

Scenario	Example
Complex subsystem simplification	Order facade combining inventory, payment, shipping
Multiple service orchestration	Notification facade coordinating email, SMS, push
Legacy system wrapping	Facade hiding complex legacy APIs
Layered system access	Application layer facade for domain services

Component Characteristics

Facade

• Simple unified interface
• Delegates to subsystem classes
• No business logic, only orchestration
• Lives in Application layer

Subsystem Classes

• Independent complex operations
• Can be used directly or through facade
• Domain or Infrastructure services

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Generation Process

Step 1: Generate Facade

Path: src/Application/{BoundedContext}/Facade/

1. {Name}Facade.php — Unified interface to subsystem

Step 2: Identify Subsystem Classes (Existing)

Paths: Domain or Infrastructure services

1. Services, Repositories, External APIs
2. Multiple components with related functionality

Step 3: Generate Tests

1. {FacadeName}Test.php — Facade orchestration verification

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File Placement

Component	Path
Facade	src/Application/{BoundedContext}/Facade/
Subsystem Classes	src/Domain/ or src/Infrastructure/
Unit Tests	tests/Unit/Application/{BoundedContext}/Facade/

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Naming Conventions

Component	Pattern	Example
Facade	{Name}Facade	OrderFacade
Test	{ClassName}Test	OrderFacadeTest

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Quick Template Reference

Facade

final readonly class {Name}Facade
{
    public function __construct(
        private {SubsystemA} $subsystemA,
        private {SubsystemB} $subsystemB,
        private {SubsystemC} $subsystemC
    ) {}

    public function {complexOperation}({params}): {returnType}
    {
        $stepA = $this->subsystemA->{methodA}({params});
        $stepB = $this->subsystemB->{methodB}($stepA);
        $stepC = $this->subsystemC->{methodC}($stepB);

        return $stepC;
    }
}

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Usage Example

// Without facade - complex coordination
$inventory = $inventoryService->reserve($productId, $quantity);
$payment = $paymentService->charge($amount, $token);
$shipment = $shippingService->schedule($address, $inventory);
$order = $orderRepository->save(new Order(...));
$notificationService->sendConfirmation($order);

// With facade - simple call
$order = $orderFacade->placeOrder($command);

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Common Facades

Facade	Purpose
OrderFacade	Coordinate inventory, payment, shipping, notifications
NotificationFacade	Send via email, SMS, push, Slack
ReportFacade	Generate PDF, Excel, CSV reports
UserRegistrationFacade	Validate, create account, send welcome email
PaymentFacade	Authorize, charge, record, notify
ExportFacade	Fetch data, transform, format, save file

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Anti-patterns to Avoid

Anti-pattern	Problem	Solution
God Facade	Facade does too much	Split into focused facades
Business Logic in Facade	Facade makes decisions	Move logic to domain services
Tight Coupling	Facade depends on concrete classes	Inject interfaces
No Subsystem Access	Clients can't bypass facade	Allow direct subsystem use
Stateful Facade	Facade holds state between calls	Keep facades stateless

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References

For complete PHP templates and examples, see:

• references/templates.md — Facade templates for order, notification, report systems
• references/examples.md — OrderFacade, NotificationFacade, ReportFacade with unit tests