Factory Generator
Generate DDD-compliant Factories for complex domain object creation.
Factory Characteristics
- •Encapsulates Creation: Hides complex instantiation logic
- •Validates Input: Ensures valid object creation
- •Named Constructors: Provides semantic creation methods
- •Domain Layer: Lives in Domain, no infrastructure dependencies
- •Returns Valid Objects: Never creates invalid domain objects
- •Static or Instance: Static for simple, instance for dependencies
When to Use Factory
| Scenario | Example |
|---|---|
| Complex construction logic | OrderFactory::createFromCart() |
| Multiple creation paths | User::register(), User::createAdmin() |
| Aggregate creation | PolicyFactory::createWithCoverage() |
| Reconstruction from persistence | OrderFactory::reconstitute() |
| Creation with validation | InvoiceFactory::create() |
Generation Process
Step 1: Determine Factory Type
- •Static Factory: No dependencies, simple validation
- •Instance Factory: Needs domain services or repositories
Step 2: Generate Factory
Path: src/Domain/{BoundedContext}/Factory/
- •
{Entity}Factory.php— Main factory class
Step 3: Define Creation Methods
- •
create()— Primary creation with validation - •
createFrom{Source}()— Creation from other objects - •
reconstitute()— Reconstruction from persistence (no validation)
Step 4: Generate Tests
Path: tests/Unit/Domain/{BoundedContext}/Factory/
File Placement
| Component | Path |
|---|---|
| Factory | src/Domain/{BoundedContext}/Factory/ |
| Unit Tests | tests/Unit/Domain/{BoundedContext}/Factory/ |
Naming Conventions
| Pattern | Example |
|---|---|
| Factory Class | {EntityName}Factory |
| Create Method | create(), createFrom{Source}() |
| Named Constructor | create{Variant}() |
| Reconstitute | reconstitute() |
| Validation | validate{Aspect}() |
Quick Template Reference
Static Factory
php
final class {Entity}Factory
{
public static function create({parameters}): {Entity}
{
self::validate({parameters});
return new {Entity}({constructorArgs});
}
public static function createFrom{Source}({SourceType} $source): {Entity}
{
return new {Entity}({mappedArgs});
}
public static function reconstitute({allFields}): {Entity}
{
return new {Entity}({allArgs});
}
private static function validate({parameters}): void
{
{validationLogic}
}
}
Instance Factory
php
final readonly class {Entity}Factory
{
public function __construct(
private {DomainService} $service,
private {Repository} $repository
) {}
public function create({parameters}): {Entity}
{
{creationLogicWithDependencies}
}
}
Anti-patterns to Avoid
| Anti-pattern | Problem | Solution |
|---|---|---|
| Infrastructure in Factory | DB calls in factory | Keep pure domain logic |
| No Validation | Creates invalid objects | Validate before creation |
| Too Many Parameters | Hard to use | Use Value Objects, Builder |
| Mutable Factory | Stateful creation | Make stateless or readonly |
| Missing Reconstitute | Can't hydrate from DB | Add reconstitute method |
References
For complete PHP templates and examples, see:
- •
references/templates.md— Static Factory, Instance Factory, Test templates - •
references/examples.md— Order, User, Policy factory examples and tests