AgentSkillsCN

acc-create-use-case

为 PHP 8.5 生成应用用例。创建协调领域对象、处理事务并分发事件的编排服务,并附带单元测试。

SKILL.md
--- frontmatter
name: acc-create-use-case
description: Generates Application Use Cases for PHP 8.5. Creates orchestration services that coordinate domain objects, handle transactions, and dispatch events. Includes unit tests.

Use Case Generator

Generate Application-layer Use Cases that orchestrate domain operations.

Use Case Characteristics

  • Single responsibility: One operation per use case
  • Orchestration: Coordinates domain objects
  • Transaction boundary: Manages atomicity
  • Event dispatch: Publishes domain events
  • No business logic: Delegates to domain
  • Framework agnostic: No HTTP/CLI concerns

When to Use

ScenarioExample
Create operationCreateOrderUseCase
State transitionConfirmOrderUseCase
External service integrationProcessPaymentUseCase
Multi-step workflowCheckoutUseCase

Generation Process

Step 1: Generate Use Case

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

  1. {Name}UseCase.php — Main orchestration class

Step 2: Generate Input DTO

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

  1. {Name}Input.php — Input data container

Step 3: Generate Output DTO

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

  1. {Name}Output.php — Result data container

Step 4: Generate Tests

Path: tests/Unit/Application/{BoundedContext}/UseCase/


File Placement

ComponentPath
Use Casesrc/Application/{BoundedContext}/UseCase/
Input DTOsrc/Application/{BoundedContext}/DTO/
Output DTOsrc/Application/{BoundedContext}/DTO/
Unit Teststests/Unit/Application/{BoundedContext}/UseCase/

Naming Conventions

PatternExample
Use Case{Verb}{Entity}UseCase
Input DTO{Name}Input
Output DTO{Name}Output or {Entity}{Result}Output

Quick Template Reference

Use Case

php
final readonly class {Name}UseCase
{
    public function __construct(
        private {Repository}Interface $repository,
        private EventDispatcherInterface $events,
        private TransactionManagerInterface $transaction
    ) {}

    public function execute({Name}Input $input): {Name}Output
    {
        return $this->transaction->transactional(function () use ($input) {
            $aggregate = $this->repository->findById($input->id);
            $aggregate->doSomething($input->data);
            $this->repository->save($aggregate);

            foreach ($aggregate->releaseEvents() as $event) {
                $this->events->dispatch($event);
            }

            return new {Name}Output(...);
        });
    }
}

Input DTO

php
final readonly class {Name}Input
{
    public function __construct(
        public {ValueObject} $id,
        {additionalProperties}
    ) {}
}

Output DTO

php
final readonly class {Name}Output
{
    public function __construct(
        public string $id,
        {resultProperties}
    ) {}

    public function toArray(): array
    {
        return ['id' => $this->id, ...];
    }
}

Anti-patterns to Avoid

Anti-patternProblemSolution
Business LogicDecisions in use caseDelegate to domain
Multiple AggregatesTransaction spans aggregatesOne aggregate per transaction
Direct Repo CallsBypassing use caseAlways use use case
Missing TransactionNo atomicityWrap in transaction
External in TransactionLong-running transactionsExternal calls outside

References

For complete PHP templates and examples, see:

  • references/templates.md — UseCase, Input, Output, Test templates with design principles
  • references/examples.md — CreateOrder, ConfirmOrder, ProcessPayment examples and tests