FASTAPI ENDPOINT: /api/v1/tasks (with JWT + Async DB)

PYDANTIC MODELS
  class TaskCreate(BaseModel):
    title: str (min_length=1, max_length=255)
    description: Optional(str) = None
    priority: Literal['low', 'medium', 'high']

  class TaskResponse(BaseModel):
    id: int
    title: str
    created_at: datetime
    model_config = ConfigDict(from_attributes=True)

ENDPOINT DEFINITION
  @app.post('/api/v1/tasks', response_model=TaskResponse, status_code=201)
  async def create_task(
    task: TaskCreate,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db)
  ) -> TaskResponse:
    db_task = Task(title=task.title, user_id=current_user.id)
    db.add(db_task)
    await db.commit()
    await db.refresh(db_task)
    return db_task

ASYNC DATABASE SETUP
  engine = create_async_engine('postgresql+asyncpg://user:pass@localhost/db')
  async_session = sessionmaker(engine, class_=AsyncSession, expire_on_commit=False)

  async def get_db():
    async with async_session() as session:
      yield session

JWT AUTHENTICATION
  SECRET_KEY = 'your-secret-key'
  ALGORITHM = 'HS256'
  
  def create_access_token(data: dict, expires_delta: timedelta):
    to_encode = data.copy()
    to_encode.update({'exp': datetime.utcnow() + expires_delta})
    return jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)

ERROR HANDLING
  @app.exception_handler(ValueError)
  async def value_error_handler(request: Request, exc: ValueError):
    return JSONResponse(status_code=400, content={'detail': str(exc)})

OPENAPI DOCUMENTATION (auto-generated)
  Visible at: /docs (Swagger UI)
  Includes: All endpoints, schemas, auth requirements
  Export: /openapi.json for client code generation