Managing environment variables in Heroku for your Python apps is important for keeping your information safe and setting up your app without putting sensitive details in the code. Here’s a simple guide on how to set up and manage these variables.

• Why Use Environment Variables?

  • They help keep important information (like API keys and database links) out of your code.
  • They let you have different settings for development, testing, and production without changing the code itself.
  • They help keep your code clean and safe, stopping any unintentional sharing of private data.

• Setting Up Environment Variables in Heroku:
  Heroku makes it easy to set and manage environment variables (also called config vars). Here’s how:

  1. Using the Heroku Dashboard:

     • Log in to your Heroku account and go to the dashboard.
     • Choose your app.
     • Click on the "Settings" tab.
     • Click on "Reveal Config Vars."
     • Add your key-value pairs (for instance, DATABASE_URL for your database connection).

  2. Using the Heroku CLI:
     If you like using command lines, you can manage environment variables with the Heroku CLI:

     • First, install Heroku CLI if you haven’t done that yet.
     • Log in using: heroku login.
     • Use the command: heroku config:set KEY=VALUE to set a variable (like heroku config:set SECRET_KEY=mysecret).
     • You can see all your environment variables by typing heroku config.

• Accessing Environment Variables in Your Python Application:
  In your Python code, you can get these environment variables using the os module:

  import os
  
  SECRET_KEY = os.environ.get('SECRET_KEY')  
  DATABASE_URL = os.environ.get('DATABASE_URL')  
  

  This way, your app can run smoothly with the right settings for where it is being used.

• Best Practices:

  • Keep Sensitive Information Safe: Always use environment variables for private information and never put them directly in your code.
  • Use .env Files Locally: While you're testing on your computer, you can use something like python-dotenv to manage your environment variables by creating a .env file. This helps keep your secrets safe.
  • Check Config Vars Often: Regularly look over your Heroku config vars to remove any old or unnecessary variables, keeping your app secure.

• When To Use Environment Variables:

  • Whenever you are working with sensitive data.
  • When different setups need different settings.
  • When launching apps that need third-party services using API keys.

By following these tips, you can easily manage environment variables in Heroku, making sure your Python app stays safe, flexible, and easy to work with.