colab-env

Outline

This Python package handles environment variables in Google Colab. Environment variables are an important infrastructure component e.g. containing secrets such as API keys that ought not to be included directly in the codebase. At the time of writing, however, Google Colab does not have built-in support for environment variables.

Our solution is to use the python-dotenv package in concert with Colab's built in authorisation tool for Google Drive. The package will attempt to

1. mount Google Drive locally
2. load environment variables from a file called vars.env

Usage

To load environment variables using colab-env you should include the following code at the top of your Colab notebook:

!pip install colab-env -qU
import colab_env

This will usually open the google.colab.drive.mount authentication flow. We use this authentication step to protect any secrets in vars.env.

Remember not to expose these secrets in the outputs of any cells!

When the authentication challenge is passed, the environment variables will either be loaded into the Google Colab environment, or vars.env will be created in your Google Drive.

To modify environment variables using colab-env you should do the following:

!pip install colab-env -qU
from colab_env import envvar_handler

... and then use envvar_handler's add_env and del_env methods to add/modify and delete environment variables respectively from vars.env.

Take it for a test-drive

Simply open up colab-env/colab_env_testbed.ipynb in Google Colab and try it out!

Contributors

Paddy Alton (paddy.alton@apolitical.co)

(with thanks to the Apolitical engineering team for assistance and review)