How do I manage environment variables in a Rails app using Docker?

How do I manage environment variables in a Rails app using Docker?

You can manage environment variables in a Rails app using Docker by defining them in your Dockerfile or docker-compose.yml file.

Can you give me an example of how to set them in docker-compose?

Sure! In your docker-compose.yml, you can set environment variables like this:

services:
  web:
    image: your-rails-app
    environment:
      - DATABASE_URL=postgres://user:password@db:5432/mydatabase
      - SECRET_KEY_BASE=your_secret_key

What if I want to use a .env file?

You can use a .env file by adding the following line to your docker-compose.yml:

env_file:
  - .env

Then, define your variables in the .env file.

Is there a way to keep sensitive data out of version control?

Yes, you can add your .env file to your .gitignore to prevent it from being tracked by Git.