Overview

This skill codifies FastAPI conventions using SQLModel, pydantic-settings, and async SQLAlchemy to build robust REST backends. It emphasizes stateless services, a unified ApiResponse wrapper, a dependency chain for authentication, module-scoped configs, and standardized error handling with AppException.

How This Skill Works

Functions are implemented as stateless services with the first parameter db: AsyncSession. Endpoints return ApiResponse[T] for consistent responses, and authentication is wired through a dependency chain: get_current_user → require_auth → require_admin. Each module can declare its own {module}_config.py to encapsulate module-specific settings.

When to Use It

• Building REST endpoints that interact with an async database using SQLModel.
• Implementing authentication and admin-restricted routes via a dependency chain.
• Creating a reusable service layer that is stateless and class-free.
• Enforcing a consistent response structure with ApiResponse[T].
• Organizing project structure with module-specific configuration files.

Quick Start

1. Step 1: Create module_config.py for your feature/module and ensure you have an AsyncSession available.
2. Step 2: Implement a stateless service function with signature (db: AsyncSession, ...).
3. Step 3: Return ApiResponse[T] from endpoints and wire auth via get_current_user → require_auth → require_admin; raise AppException when needed.

Best Practices

• Write services as stateless functions with the first parameter db: AsyncSession.
• Always return results wrapped in ApiResponse[T] for uniformity.
• Use the dependency chain get_current_user → require_auth → require_admin for auth.
• Keep module-level configurations in {module}_config.py to isolate concerns.
• Handle errors with AppException(status, message, error_code) for frontend clarity.

Example Use Cases

• User service: stateless CRUD operations using AsyncSession with ApiResponse wrappers.
• Auth module: get_current_user → require_auth → require_admin gating sensitive endpoints.
• Product module: separate {product}_config.py containing feature toggles and DB settings.
• Error handling: endpoints raise AppException with specific status and error_code for frontend mapping.
• Routing: endpoints consistently return ApiResponse[T] across services and models.

Frequently Asked Questions