python - Reading in environment variables from an environment file

Question

I'd like to run in a local environment a Python script which is normally run in a Docker container. The docker-compose.yml specifies an env_file which looks (partially) like the following:

DB_ADDR=rethinkdb
DB_PORT=28015
DB_NAME=ipercron

In order to run this locally, I would like these lines to be converted to

os.environ['DB_ADDR'] = 'rethinkdb'
os.environ['DB_PORT'] = '28015'
os.environ['DB_NAME'] = 'ipercron'

I could write my parser, but I was wondering if there are any existing modules/tools to read in environment variables from configuration files?

Answer 1

I use Python Dotenv Library. Just install the library pip install python-dotenv, create a .env file with your environment variables, and import the environment variables in your code like this:

import os
from dotenv import load_dotenv

load_dotenv()

MY_ENV_VAR = os.getenv('MY_ENV_VAR')

From the .env file:

MY_ENV_VAR="This is my env var content."

This is the way I do when I need to test code outside my docker system and prepare it to return it into docker again.