Environment variable management in Flask - Mini Project: Build & Apply

Environment Variable Management in Flask

📖 Scenario: You are building a simple Flask web application that needs to use secret keys and configuration values safely. Instead of hardcoding these values, you will use environment variables to keep them secure and flexible.

🎯 Goal: Learn how to set up environment variables and access them in a Flask app to manage configuration like secret keys.

📋 What You'll Learn

Create environment variables for configuration

Access environment variables in Flask app

Use environment variables to set Flask app secret key

Run Flask app with environment variable configuration

💡 Why This Matters

🌍 Real World

Managing secret keys and configuration through environment variables is a common practice to keep sensitive data safe and make apps flexible across different environments.

💼 Career

Understanding environment variable management is essential for backend developers and DevOps roles to build secure and configurable web applications.

1

Set up environment variables

Create a dictionary called env_vars with these exact entries: 'SECRET_KEY': 'mysecret123' and 'DEBUG': 'true' to simulate environment variables.

Flask

# Your code here

Need a hint?

Use a Python dictionary to hold the environment variables as key-value pairs.

2

Configure Flask app with environment variables

Import Flask from flask and create a Flask app called app. Then create a variable called secret_key that gets the value of 'SECRET_KEY' from env_vars.

Flask

env_vars = {'SECRET_KEY': 'mysecret123', 'DEBUG': 'true'}
# Your code here

Need a hint?

Use env_vars['SECRET_KEY'] to get the secret key value.

3

Set Flask app secret key from environment variable

Set the Flask app's secret_key attribute to the variable secret_key you created.

Flask

env_vars = {'SECRET_KEY': 'mysecret123', 'DEBUG': 'true'}
from flask import Flask
app = Flask(__name__)
secret_key = env_vars['SECRET_KEY']
# Your code here

Need a hint?

Assign the secret key to app.secret_key to configure Flask.

4

Add a route and run the Flask app

Add a route for "/" that returns the string "Hello, Flask!". Then add the code to run the Flask app with debug=true if env_vars['DEBUG'] is 'true'.

Flask

env_vars = {'SECRET_KEY': 'mysecret123', 'DEBUG': 'true'}
from flask import Flask
app = Flask(__name__)
secret_key = env_vars['SECRET_KEY']
app.secret_key = secret_key
# Your code here

Need a hint?

Use @app.route('/') to create the route and app.run(debug=...) to start the server with debug mode from environment variable.