Python/Django - Avoid saving passwords in source code

Although environment variables are convenient for a lot of configuration, putting passwords in environment variables is not secure. With the alternative being a configuration file outside regular version control, here are some various cons:

  • Environment variables might accidentally leak (through debugging channels that might get transmitted via plaintext, to end-users, or to unexpected places in the filesystem like ~/.*sh_history).

  • Configuration files might accidentally get added to version control and end up in repositories accessible to people without deployment privileges.

Read the blog post Environment Variables Considered Harmful for Your Secrets for more arguments: The environment is accessible to the entire process, is inherited to child (and possibly 3rd-party) processes, and there exists no clear assumption among external developers to treat environment variables as confidential.

The simplest configuration file format in Python is simply a Python module.

Although I wasn't able to come across anything Python-specific on stackoverflow, I did find a website that was helpful, and thought I'd share the solution with the rest of the community.

The solution: environment variables.

Note: Although environment variables are similar in both Linux/Unix/OS X and in the Windows worlds, I haven't tested this code on a Windows machine. Please let me know if it works.

In your bash/sh shell, type:

export MYAPP_DB_USER='myapp'
export MYAPP_DB_PASSWORD='testing123'

And in your Django file:

DATABASE_USER = os.environ.get("MYAPP_DB_USER", '')

In this case, the username and password would default to an empty string if the environment variable didn't exist.