In Flask application what is the difference between @app.teardown_request and @app.teardown_appcontext?

Question

I was going through a flask application and found the use of @app.teardown_request. Can anyone please demystify the real reason of using @app.teardown_request rather than @app.teardown_appcontext?

In other words what exactly is the difference?

Answer 1

@app.teardown_appcontext - Bind a function after each request, even if an exception is encountered.

@app.teardown_request - Registers a function to be called at the end of each request whether it was successful or an exception was raised. It is a good place to cleanup request scope objects like a database session/transaction.

https://github.com/pallets/flask-sqlalchemy/issues/379