SQLAlchemy database migrations for Flask applications using Alembic
Flask-Migrate
Flask-Migrate is an extension that handles SQLAlchemy database migrations for Flask applications using Alembic. The database operations are provided as command-line arguments under the flask db command.
Installation
Install Flask-Migrate with pip:
pip install Flask-Migrate
Example
This is an example application that handles database migrations through Flask-Migrate:
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_migrate import Migrate
app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///app.db'
db = SQLAlchemy(app)
migrate = Migrate(app, db)
class User(db.Model):
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(128))
With the above application you can create the database or enable migrations if the database already exists with the following command:
$ flask db init
Note that the FLASK_APP environment variable must be set according to the Flask