django-guide

Guide Django

1. Choisir l'architecture

2. Initialiser le projet

pip install django djangorestframework django-environ
django-admin startproject config .   # config = dossier settings
python manage.py startapp orders     # une app par domaine métier

Structure recommandée :

project/
  config/
    settings/
      base.py      # commun
      dev.py       # DEBUG=True, SQLite
      prod.py      # ALLOWED_HOSTS, DATABASES Postgres, STATIC_ROOT
    urls.py
    wsgi.py
  orders/
    models.py
    views.py
    serializers.py
    urls.py
    admin.py
    tests/
  manage.py
  .env

config/settings/base.py :

from environ import Env
env = Env()
Env.read_env()

SECRET_KEY = env("SECRET_KEY")
DATABASES = {"default": env.db()}  # DATABASE_URL=postgres://...

3. Concevoir les models

from django.db import models
from django.utils.translation import gettext_lazy as _

class Order(models.Model):
    class Status(models.TextChoices):
        PENDING  = "pending",  _("En attente")
        SHIPPED  = "shipped",  _("Expédié")

    reference   = models.CharField(max_length=32, unique=True)
    customer    = models.ForeignKey("users.User", on_delete=models.PROTECT,
                                    related_name="orders")
    status      = models.CharField(max_length=16, choices=Status.choices,
                                    default=Status.PENDING)
    created_at  = models.DateTimeField(auto_now_add=True)

    class Meta:
        ordering = ["-created_at"]
        indexes  = [models.Index(fields=["status", "created_at"])]

    def __str__(self):
        return f"Order {self.reference}"

    def clean(self):
        # Validation métier centralisée ici, pas dans la vue
        if self.status == self.Status.SHIPPED and not self.reference:
            raise ValidationError("Reference requise avant expédition.")