How can I implement authentication in a Flask app?

How can I implement authentication in a Flask app?

You can use Flask-Login for user session management. Would you like a code example?

Yes, please provide a simple code example.

Here's a basic example:

from flask import Flask, redirect, url_for, request
from flask_login import LoginManager, UserMixin, login_user, login_required, logout_user

app = Flask(__name__)
app.secret_key = 'your_secret_key'
login_manager = LoginManager()
login_manager.init_app(app)

class User(UserMixin):
    def __init__(self, id):
        self.id = id

@login_manager.user_loader
def load_user(user_id):
    return User(user_id)

@app.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'POST':
        user = User(request.form['username'])
        login_user(user)
        return redirect(url_for('protected'))
    return 'Login Form'

@app.route('/protected')
@login_required
def protected():
    return 'Logged in successfully!'

if __name__ == '__main__':
    app.run()

What if I want to add registration functionality?

You can create a registration route to save user details in a database. Would you like to see that as well?