create-api-module

Development

Creates a new API module following Clean Architecture with TDD. Use when adding new API endpoints, creating backend features, implementing domain entities, or when the user says "create module", "add endpoint", "new backend feature".

QUICK START

How to use this skill

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Source SKILL.md: https://github.com/majiayu000/claude-skill-registry/blob/HEAD/skills/data/create-api-module/SKILL.md

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Create API Module

Creates a new backend module following Clean Architecture with API, Domain, and Infrastructure layers.

Workflow

Create directory structure at back/src/api/{module}/
Create infrastructure layer: models, repository (interface + implementation), dependencies
Create domain layer: business logic functions, exceptions
Create API layer: router, schemas
Register router in back/src/api/routes.py
Create tests in back/tests/api/{module}/
Create migration: docker compose exec back uv run alembic revision --autogenerate -m "Add {module} table"

Directory Structure

back/src/api/{module}/
├── api/
│   ├── router.py         # FastAPI endpoints
│   └── schemas.py        # Pydantic request/response models
├── domain/
│   ├── exception.py      # Domain exceptions
│   └── {action}.py       # Business logic functions
└── infrastructure/
    ├── models.py         # SQLModel database models
    ├── repository.py     # Repository interface + implementation
    └── dependencies.py   # FastAPI dependency injection

Quick Scaffold

Generate boilerplate structure:

python .claude/skills/create-api-module/scripts/scaffold_module.py {module_name}

Code Patterns

For detailed code patterns, see PATTERNS.md.

Real Examples

For complete working examples from this codebase, see EXAMPLES.md.

Important Conventions

Table names: plural, lowercase (items, users, notifications)
Model class names: {Entity}Db (ItemDb, UserDb)
Router names: {entity}_router (item_router, user_router)
Test names: test_when_{condition}_then_{outcome}
Always use UUID for primary keys
Soft delete: Use deleted_at field instead of hard delete
Type hints: Required everywhere, use | for union types (not Optional)

After Creating Module

Run tests: uv run pytest tests/api/{module}/ -v
Format code: task format
Create migration if needed
Test endpoints via /docs locally