Comment Créer une API REST Professionnelle avec Flask

Comment Créer une API REST Professionnelle avec Flask

Flask est léger mais très puissant pour créer des APIs. Voici comment faire les choses correctement.

mon_api/
├── app.py
├── models/
│ ├── user.py
│ └── article.py
├── routes/
│ ├── users.py
│ ├── articles.py
│ └── auth.py
├── services/
│ ├── user_service.py
│ └── auth_service.py
└── requirements.txt

Installation

pip install flask flask-sqlalchemy flask-marshmallow flask-cors python-dotenv

Configuration de Base

from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_cors import CORS
import os

app = Flask(__name__)
CORS(app)

# Configuration
app.config['SQLALCHEMY_DATABASE_URI'] = os.getenv('DATABASE_URL')
app.config['JSON_SORT_KEYS'] = False

db = SQLAlchemy(app)

Modèles

from datetime import datetime

class User(db.Model):
__tablename__ = 'users'

id = db.Column(db.Integer, primary_key=True)
email = db.Column(db.String(120), unique=True, nullable=False)
name = db.Column(db.String(120), nullable=False)
password_hash = db.Column(db.String(255))
created_at = db.Column(db.DateTime, default=datetime.utcnow)

def to_dict(self):
return {
'id': self.id,
'email': self.email,
'name': self.name,
'created_at': self.created_at.isoformat()
}

Routes (Endpoints)

from flask import Blueprint, request, jsonify
from models.user import User
from db import db

users_bp = Blueprint('users', __name__, url_prefix='/api/v1/users')

@users_bp.route('', methods=['GET'])
def get_users():
page = request.args.get('page', 1, type=int)
users = User.query.paginate(page=page, per_page=10)
return jsonify({
'data': [u.to_dict() for u in users.items],
'total': users.total,
'pages': users.pages
})

@users_bp.route('/<int:user_id>', methods=['GET'])
def get_user(user_id):
user = User.query.get_or_404(user_id)
return jsonify(user.to_dict())

@users_bp.route('', methods=['POST'])
def create_user():
data = request.get_json()

# Validation
if not data.get('email') or not data.get('name'):
return jsonify({'error': 'Email et name requis'}), 400

if User.query.filter_by(email=data['email']).first():
return jsonify({'error': 'Email déjà utilisé'}), 409

user = User(email=data['email'], name=data['name'])
db.session.add(user)
db.session.commit()

return jsonify(user.to_dict()), 201

@users_bp.route('/<int:user_id>', methods=['PUT'])
def update_user(user_id):
user = User.query.get_or_404(user_id)
data = request.get_json()

if 'name' in data:
user.name = data['name']

db.session.commit()
return jsonify(user.to_dict())

@users_bp.route('/<int:user_id>', methods=['DELETE'])
def delete_user(user_id):
user = User.query.get_or_404(user_id)
db.session.delete(user)
db.session.commit()
return '', 204

# Enregistrer le blueprint
app.register_blueprint(users_bp)

Gestion des Erreurs

@app.errorhandler(404)
def not_found(error):
return jsonify({'error': 'Ressource non trouvée'}), 404

@app.errorhandler(500)
def internal_error(error):
db.session.rollback()
return jsonify({'error': 'Erreur serveur'}), 500

Authentification JWT

pip install flask-jwt-extended

from flask_jwt_extended import JWTManager, create_access_token, jwt_required

app.config['JWT_SECRET_KEY'] = os.getenv('JWT_SECRET_KEY')
jwt = JWTManager(app)

@app.route('/api/v1/auth/login', methods=['POST'])
def login():
data = request.get_json()
user = User.query.filter_by(email=data['email']).first()

if not user or not user.check_password(data['password']):
return jsonify({'error': 'Identifiants invalides'}), 401

access_token = create_access_token(identity=user.id)
return jsonify({'access_token': access_token})

@app.route('/api/v1/protected', methods=['GET'])
@jwt_required()
def protected_route():
current_user_id = get_jwt_identity()
return jsonify({'message': f'User {current_user_id}'})

Déploiement

# Avec Gunicorn
pip install gunicorn
gunicorn -w 4 -b 0.0.0.0:5000 app:app