Session data storage in Flask - Mini Project: Build & Apply

Session Data Storage with Flask

📖 Scenario: You are building a simple web app using Flask. You want to remember a user's name during their visit without asking every time. This is like remembering a friend's name when they come to your house.

🎯 Goal: Create a Flask app that stores a user's name in session data and shows it on the homepage.

📋 What You'll Learn

Create a Flask app instance

Set a secret key for sessions

Store a user's name in the session

Retrieve and display the stored name on the homepage

💡 Why This Matters

🌍 Real World

Web apps often need to remember users during their visit without asking repeatedly. Session data storage helps keep user info like login status or preferences.

💼 Career

Understanding session management is key for backend web developers to create personalized and secure user experiences.

1

Create Flask app and set secret key

Write code to import Flask and session from flask. Then create a Flask app instance called app. Finally, set the secret key of app to the string 'mysecretkey'.

Flask

from flask import Flask, session

# Your code here

Need a hint?

The secret key is needed to keep session data safe. Use app.secret_key = 'mysecretkey'.

2

Create a route to store the user's name in session

Add a route for /setname using @app.route('/setname'). Define a function called set_name that stores the string 'Alice' in the session under the key 'username'. Return the string 'Name stored in session.'.

Flask

from flask import Flask, session

app = Flask(__name__)
app.secret_key = 'mysecretkey'

# Your code here

Need a hint?

Use session['username'] = 'Alice' to save the name.

3

Create a homepage route to show the stored name

Add a route for / using @app.route('/') . Define a function called home that gets the 'username' from session using session.get('username'). Return a string f'Hello, {username}!' if the name exists, otherwise return 'Hello, Guest!'.

Flask

from flask import Flask, session

app = Flask(__name__)
app.secret_key = 'mysecretkey'

@app.route('/setname')
def set_name():
    session['username'] = 'Alice'
    return 'Name stored in session.'

# Your code here

Need a hint?

Use session.get('username') to safely get the name.

4

Add the app run command to start the server

Add the code if __name__ == '__main__': and inside it call app.run(debug=True) to start the Flask server in debug mode.

Flask

from flask import Flask, session

app = Flask(__name__)
app.secret_key = 'mysecretkey'

@app.route('/setname')
def set_name():
    session['username'] = 'Alice'
    return 'Name stored in session.'

@app.route('/')
def home():
    username = session.get('username')
    if username:
        return f'Hello, {username}!'
    else:
        return 'Hello, Guest!'

# Your code here

Need a hint?

This code runs the app when you start the script.