Add an API Endpoint¶

This guide walks through the steps to add a new endpoint to the D2S backend.

Overview¶

Adding a new endpoint typically involves changes across several layers:

Model — Define or update SQLAlchemy models in backend/app/models/
Schema — Define Pydantic request/response schemas in backend/app/schemas/
CRUD — Implement database operations in backend/app/crud/
Endpoint — Create the route handler in backend/app/api/api_v1/endpoints/
Router — Register the endpoint in backend/app/api/api_v1/api.py
Tests — Add test coverage in backend/app/tests/

Step 1: Define the model¶

If your endpoint requires a new database table, create a model in backend/app/models/. Follow existing conventions — models use PascalCase and inherit from the project's base class.

Step 2: Create Pydantic schemas¶

Define request and response schemas in backend/app/schemas/. At minimum, create schemas for create, update, and read operations.

Step 3: Implement CRUD operations¶

Add database operations in backend/app/crud/. Follow the existing pattern of extending the base CRUD class.

Step 4: Create the endpoint¶

Create a new file in backend/app/api/api_v1/endpoints/ with your route handlers. Use FastAPI's dependency injection for authentication and authorization:

from fastapi import APIRouter, Depends

router = APIRouter()

@router.get("/")
def list_items(current_user = Depends(get_current_approved_user)):
    ...

Step 5: Register the router¶

Add the new router to backend/app/api/api_v1/api.py:

from app.api.api_v1.endpoints import your_module

api_router.include_router(
    your_module.router,
    prefix="/your-resource",
    tags=["your-resource"],
)

Step 6: Add tests¶

Create a test file in backend/app/tests/ following the test_<feature>.py naming convention. See the Run the Test Suite guide for running tests.