Flask Application Factory

Application Factory Pattern

# app/__init__.py
from flask import Flask
from .extensions import db, migrate, login_manager

def create_app(config_name="default"):
    app = Flask(__name__)
    app.config.from_object(config[config_name])

    # Init extensions
    db.init_app(app)
    migrate.init_app(app, db)
    login_manager.init_app(app)

    # Register blueprints
    from .auth import auth_bp
    from .main import main_bp
    from .api  import api_bp
    app.register_blueprint(auth_bp, url_prefix="/auth")
    app.register_blueprint(main_bp)
    app.register_blueprint(api_bp,  url_prefix="/api")

    return app

# run.py
from app import create_app
app = create_app()

if __name__ == "__main__":
    app.run(debug=True)