Remember me functionality in Flask - Mini Project: Build & Apply

Remember Me Functionality in Flask

📖 Scenario: You are building a simple login page for a website using Flask. You want to add a "Remember Me" checkbox so that users can stay logged in even after closing their browser.

🎯 Goal: Create a Flask app that has a login form with a "Remember Me" checkbox. When the user logs in and checks this box, their login session should persist even after closing the browser. If unchecked, the session should end when the browser closes.

📋 What You'll Learn

Create a Flask app with a login route

Add a login form with username, password, and a "Remember Me" checkbox

Use Flask's session management to remember the user based on the checkbox

Set the session to be permanent only if "Remember Me" is checked

💡 Why This Matters

🌍 Real World

Remember Me functionality is common on websites to improve user experience by keeping users logged in across browser sessions.

💼 Career

Understanding session management and user authentication is essential for backend web development roles.

1

Set up Flask app and login route

Create a Flask app instance called app and define a route /login that accepts both GET and POST methods.

Flask

from flask import Flask, request, session, redirect, url_for, render_template_string

# Your code here

Need a hint?

Use Flask(__name__) to create the app and decorate a function with @app.route('/login', methods=['GET', 'POST']).

2

Add login form HTML with Remember Me checkbox

Inside the login function, create a string variable called login_form that contains HTML for a form with fields: username, password, and a checkbox named remember labeled "Remember Me". The form should submit to /login using POST.

Flask

from flask import Flask, request, session, redirect, url_for, render_template_string

app = Flask(__name__)
app.secret_key = 'secret-key'

@app.route('/login', methods=['GET', 'POST'])
def login():
    login_form = '''
    
    '''
    # Your code here

Need a hint?

Use a multi-line string with ''' to store the HTML form. Include a checkbox input with name="remember".

3

Implement login POST logic with Remember Me session setting

Inside the login function, check if the request method is POST. If yes, get the username and check if the remember checkbox is in request.form. Set session['username'] to the username. Set session.permanent to True if remember is checked, otherwise False. Then redirect to /dashboard. If GET, return the login_form using render_template_string.

Flask

from flask import Flask, request, session, redirect, url_for, render_template_string

app = Flask(__name__)
app.secret_key = 'secret-key'

@app.route('/login', methods=['GET', 'POST'])
def login():
    login_form = '''
    
        Username:
        
        Password:
        
        
             Remember Me
        
        Login
    
    '''

    # Your code here

Need a hint?

Check request.method. Use session.permanent = True if remember is checked. Redirect after login.

4

Add dashboard route to show logged-in user

Create a new route /dashboard that shows a welcome message with the logged-in username from the session. If no user is logged in, redirect to /login.

Flask

from flask import Flask, request, session, redirect, url_for, render_template_string

app = Flask(__name__)
app.secret_key = 'secret-key'

@app.route('/login', methods=['GET', 'POST'])
def login():
    login_form = '''
    
        Username:
        
        Password:
        
        
             Remember Me
        
        Login
    
    '''

    if request.method == 'POST':
        username = request.form['username']
        remember = 'remember' in request.form
        session['username'] = username
        session.permanent = remember
        return redirect(url_for('dashboard'))
    return render_template_string(login_form)

# Your code here

Need a hint?

Check if session['username'] exists. Show welcome message or redirect to login.