implementing Memory Leak in Flask Application with SQLAlchemy 1.4 on Python 3.11
I'm writing unit tests and I'm relatively new to this, so bear with me. I'm stuck on something that should probably be simple. I'm working with a memory leak in my Flask application that uses SQLAlchemy 1.4 on Python 3.11. After running the application for a few hours, I notice that the memory usage keeps increasing, and it eventually leads to the application crashing. I've tried to track down the source of the leak but haven’t had much success so far. Here’s a simplified version of how I'm setting up my SQLAlchemy session: ```python from flask import Flask from flask_sqlalchemy import SQLAlchemy app = Flask(__name__) app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///test.db' db = SQLAlchemy(app) class User(db.Model): id = db.Column(db.Integer, primary_key=True) username = db.Column(db.String(80), unique=True, nullable=False) @app.route('/add_user/<username>') def add_user(username): user = User(username=username) db.session.add(user) db.session.commit() return f'User {username} added!' if __name__ == '__main__': app.run(debug=True) ``` I am committing each new user to the database within the route. I've also set up a periodic task to clear out old user data, but the memory usage still rises. I tried using `db.session.remove()` after each request to ensure the session is cleared, but it didn’t make a difference. To further investigate, I used memory profiling tools, and it seems that some objects from SQLAlchemy are not being garbage collected. Is there a specific way to manage the session lifecycle when using Flask with SQLAlchemy to prevent memory leaks? Any insights or suggestions would be greatly appreciated. My development environment is Linux. I'd really appreciate any guidance on this. I'm working on a application that needs to handle this. Is there a better approach? The stack includes Python and several other technologies. Any ideas what could be causing this?