This is an example application written to demonstrate using SQLAlchemy with Flask web framework.

When the user opens the application, the list of existing comments are presented alongwith an option to enter a new comment. The entered comment is validated and saved to the database and listed in the home page. If there are any validation errors, they are presented to the user alongwith the form

We have also explained different types of web authentication:

• HTTP Basic & Form Based Authentication
• Certificate Based Authentication and Cookies
• Protocol Based Passwordless Authentication i.e. OAuth

To understand it in details refer to this doc.