Flask-SQLAlchemy db.create_all() got an unexpected keyword argument 'app'

Question

I'm following a tutorial for creating a Flask app with Flask-SQLAlchemy. However, it has started raising an error when creating the database. How do I create the database?

from flask import Flask
from flask_sqlalchemy import SQLAlchemy

db = SQLAlchemy()

def create_app():
    app = Flask(__name__)
    app.config["SQLALCHEMY_DATABASE_URI"] = "sqlite:///project.db"
    db.init_app(app)

    from . import models

    create_database(app)
    return app

def create_database(app):
    if not path.exists("website/project.db"):
        db.create_all(app=app)
        print("created database")

The line db.create_all(app=app) gives me this error:

SQLAlchemy.create_all() got an unexpected keyword argument 'app'

Answer 1

Flask-SQLAlchemy 3 no longer accepts an app argument to methods like create_all. Instead, it always requires an active Flask application context.

db = SQLAlchemy()

def create_app():
    app = Flask(__name__)
    app.config["SQLALCHEMY_DATABASE_URI"] = "sqlite:///project.db"
    db.init_app(app)

    from . import models

    with app.app_context():
        db.create_all()

    return app

There is no need for that create_database function. SQLAlchemy will already not overwrite an existing file, and the only time the database wouldn't be created is if it raised an error.