Proxy Pattern Generator

Creates Proxy pattern infrastructure for controlling access to objects.

When to Use

Scenario	Example
Lazy initialization	Load expensive resources on first access
Access control	Check permissions before delegating
Caching	Cache results of expensive operations
Logging	Log calls to real subject

Component Characteristics

Subject Interface

• Defines operations
• Shared by proxy and real subject
• Enables transparent substitution

Real Subject

• Actual implementation
• Contains business logic
• May be expensive to create

Proxy

• Implements subject interface
• Controls access to real subject
• Adds additional behavior

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Generation Process

Step 1: Generate Subject Interface

Path: src/Domain/{BoundedContext}/

1. {Name}Interface.php — Operations contract

Step 2: Generate Proxy

Path: src/Infrastructure/{BoundedContext}/Proxy/

1. Lazy{Name}Proxy.php — Lazy initialization
2. Caching{Name}Proxy.php — Result caching
3. AccessControl{Name}Proxy.php — Permission checks
4. Logging{Name}Proxy.php — Call logging

Step 3: Generate Tests

1. {ProxyName}Test.php — Proxy behavior verification

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File Placement

Component	Path
Subject Interface	src/Domain/{BoundedContext}/
Real Subject	src/Domain/ or src/Infrastructure/
Proxy	src/Infrastructure/{BoundedContext}/Proxy/
Unit Tests	tests/Unit/Infrastructure/{BoundedContext}/Proxy/

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Naming Conventions

Component	Pattern	Example
Subject Interface	{Name}Interface	RepositoryInterface
Real Subject	{Name}	UserRepository
Proxy	{Type}{Name}Proxy	LazyUserRepositoryProxy
Test	{ClassName}Test	LazyUserRepositoryProxyTest

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Quick Template Reference

Proxy

final class {Type}{Name}Proxy implements {Name}Interface
{
    private ?{Name}Interface $realSubject = null;

    public function __construct(
        private \Closure $factory
    ) {}

    public function {operation}({params}): {returnType}
    {
        {beforeBehavior}

        $result = $this->getRealSubject()->{operation}({args});

        {afterBehavior}

        return $result;
    }

    private function getRealSubject(): {Name}Interface
    {
        if ($this->realSubject === null) {
            $this->realSubject = ($this->factory)();
        }

        return $this->realSubject;
    }
}

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Usage Example

// Lazy loading proxy
$repository = new LazyUserRepositoryProxy(
    fn() => new UserRepository($connection)
);

// Real subject created only on first call
$user = $repository->findById($id);

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Common Proxies

Proxy	Purpose
LazyLoadingProxy	Defer expensive object creation
CachingProxy	Cache method results
AccessControlProxy	Check permissions before execution
LoggingProxy	Log all method calls
MetricsProxy	Collect performance metrics
RetryProxy	Retry failed operations

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Anti-patterns to Avoid

Anti-pattern	Problem	Solution
Proxy != Real Subject	Behavior differs	Proxy must be transparent
Heavy Proxy	Too much logic	Keep proxies focused
Missing Interface	Can't substitute proxy	Use shared interface
Leaky State	Proxy state affects behavior	Keep proxies stateless when possible
Multiple Responsibilities	Proxy does many things	One proxy, one concern

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References

For complete PHP templates and examples, see:

• references/templates.md — Lazy loading, caching, access control proxy templates
• references/examples.md — Repository, service proxies with unit tests