ag-referencia-python

Skill: Python Patterns

Referencia de patterns para projetos Python.

Quando Ativar

• Trabalhando em projeto Python
• Configurando ambiente virtual
• Escrevendo testes com pytest

Estrutura Recomendada

projeto/
├── README.md
├── requirements.txt
├── requirements-dev.txt
├── pyproject.toml
├── .env.example
├── src/
│   └── nome_projeto/
│       ├── __init__.py
│       ├── main.py
│       ├── config.py
│       ├── models/
│       ├── services/
│       ├── repositories/
│       └── utils/
├── tests/
│   ├── conftest.py
│   ├── test_models/
│   └── test_services/
└── scripts/

Ambiente Virtual

python -m venv .venv
source .venv/bin/activate      # Linux/Mac
.venv\Scripts\activate         # Windows
pip install -r requirements.txt
pip freeze > requirements.txt

Type Hints

from typing import Optional
from dataclasses import dataclass

def greet(name: str) -> str:
    return f"Ola, {name}!"

def find_user(user_id: str) -> Optional["User"]:
    ...

def process_items(items: list[str]) -> dict[str, int]:
    return {item: len(item) for item in items}

@dataclass
class User:
    id: str
    email: str
    name: str
    age: int | None = None

Pydantic (Validacao)

from pydantic import BaseModel, EmailStr, Field
from uuid import UUID, uuid4

class UserCreate(BaseModel):
    email: EmailStr
    name: str = Field(min_length=1, max_length=255)

class User(UserCreate):
    id: UUID = Field(default_factory=uuid4)

    class Config:
        from_attributes = True

Pytest

# tests/conftest.py
import pytest

@pytest.fixture
def sample_user():
    return User(id="123", email="[email protected]", name="Test")

# tests/test_services/test_user_service.py
class TestUserService:
    def test_create_user_success(self, mock_db):
        service = UserService(db=mock_db)
        user = service.create(email="[email protected]", name="Test")
        assert user.email == "[email protected]"

    @pytest.mark.parametrize("email,valid", [
        ("[email protected]", True),
        ("invalid", False),
    ])
    def test_validate_email(self, email: str, valid: bool):
        assert UserService.validate_email(email) == valid