Getting started with Flask-Login

getting-started-with-flask-login.md

Getting started with Flask-Login

Pre-requisites

• Flask pip install flask
• Flask-Login pip install flask-login

Steps

• Create your user model class: User. This would be a class that stores information about your User. Essentially the user_name, user_id, email, etc.
• Create your user access class: UserDAO (User Data Access Object). This is the wrapper around your user model that uses the User class and performs functions around it (signup, signin, validate, etc)
• Initialize the flask app with app=Flask(__name__)
• Set a secret key, Flask-Login uses sessions and sessions in Flask need a secret Key
• Create an instance of LoginManager class login_manager = LoginManager()
• Initialize the LoginManager with the app that was created login_manager.init_app(app)
• In User, inherit the UserMixin from Flask-Login. class User(UserMixin). Implement the required methods: is_authenticated, is_active, is_anonymous and get_id
• Decorate a method with @login_manager.user_loader that returns the User object given the ID (the UserDAO would be where this method would be written)
• In the login end point, once the app side validation is done, register the user into Flask-Login with the login_user method. The login_user method takes a User object. login_user(UserDAO.get(user_name)). This would register a session with that user
• After that, any route that needs authentication can be decorated with @login_required and Flask-Login takes care of the rest
• To logout, call the logout_user() method
• To get the current user's ID the current_user.get_id() method can be used. If there is no one logged in, current_user.get_id() would return None

DONE.

Implementation

• Check this repo.