OpenAPI Development Skill

Context (Input)

• Adding new OpenAPI endpoint factories under src/Shared/Application/OpenApi/Factory/Endpoint/
• Adding/editing request/response/schema factories under src/Shared/Application/OpenApi/Factory/
• Adding/editing processors that transform the generated spec
• Fixing OpenAPI validation errors from:
  • make validate-openapi-spec (Spectral)
  • make openapi-diff
  • make schemathesis-validate

Task (Function)

Develop and maintain OpenAPI specification generation in a way that:

• Keeps code quality thresholds intact (complexity, style, architecture)
• Preserves immutability when working with API Platform OpenAPI models (with*() methods)
• Produces a spec that passes Spectral and stays diff-stable

Success Criteria:

• make generate-openapi-spec produces .github/openapi-spec/spec.yaml
• make validate-openapi-spec passes

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Architecture Overview

This service uses a layered OpenAPI customization approach:

src/Shared/Application/OpenApi/
├── Builder/               # Build common OpenAPI pieces
├── Extractor/             # Extract example values / payload fragments
├── Factory/               # Endpoint/Request/Response/Schema/UriParameter factories
├── Transformer/           # Transform/modify OpenAPI operations, parameters, responses
├── ValueObject/ + Enum/   # Strongly typed OpenAPI-related value objects
└── Factory/OpenApiFactory.php  # Main coordinator (decorator)

config/services.yaml decorates API Platform’s OpenAPI factory with:

• App\Shared\Application\OpenApi\Factory\OpenApiFactory
• !tagged_iterator ‘app.openapi_endpoint_factory’

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Key Principles (Keep Complexity Low)

1. Single Responsibility: one class = one transformation.
2. Immutability: prefer with*() methods; avoid mutating nested arrays unless API Platform forces it.
3. OPERATIONS constant: avoid chaining withGet/withPost/... repeatedly.
4. Readable guard clauses: prefer early returns over deep nesting.
5. Functional style: array_map, array_filter, array_keys over procedural mutation.

See: reference/processor-patterns.md

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How to Add New Components

Adding a New Transformer

• Create a focused class under src/Shared/Application/OpenApi/Transformer/.
• Implement a single public entry method, e.g. transform(OpenApi $openApi): OpenApi.
• Iterate paths using array_keys($openApi->getPaths()->getPaths()).
• Apply changes per PathItem using an OPERATIONS constant + dynamic with/get calls.
• Do NOT create new directories (e.g. Augmenter/, Enricher/, Helper/). New OpenAPI transformation classes belong in Transformer/. Existing directories (Sanitizer/) are in use — do not duplicate their purpose.

Adding a New Endpoint Factory

• Implement EndpointFactoryInterface under src/Shared/Application/OpenApi/Factory/Endpoint/.
• It is auto-tagged by _instanceof in config/services.yaml.
• It will be invoked by src/Shared/Application/OpenApi/Factory/OpenApiFactory.php.

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Testing / Validation

Run locally (preferred order):

make generate-openapi-spec
make validate-openapi-spec
make openapi-diff
make schemathesis-validate

Notes:

• make validate-openapi-spec runs ./scripts/validate-openapi-spec.sh (Spectral).
• make schemathesis-validate runs Examples and Coverage phases.

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Related Skills

• complexity-management for refactoring when PHPInsights/PHPMD fails
• documentation-sync when spec changes require docs updates