Rails: use another .env file - ruby-on-rails

Question

I am running a mastodon server with two instances on the same server.
Mastodon is basically a rails app and has the command line tool called tootctl.
Normally you use it like so:
RAILS_ENV=production bin/tootctl accounts modify alice --role Owner
This uses the default env file .env.production that was created when installing the first instance.
But now I need to manage the second instance for which I need to use the second env file .env.production.de
Question: How do I tell rails to use another .env file than the default one?
I would need something like
RAILS_ENV=production RAILS_ENV_FILE=.env.production.de bin/tootctl accounts modify alice --role Owner .

Answer 1

For each of the Rails apps you can use Option Three: Use a local_env.yml File as found in this article: http://railsapps.github.io/rails-environment-variables.html
So something like:
The local_env.yml File
Create a file config/local_env.yml:
# Rename this file to local_env.yml
# Add account settings and API keys here.
# This file should be listed in .gitignore to keep your settings secret!
# Each entry gets set as a local environment variable.
# This file overrides ENV variables in the Unix shell.
# For example, setting:
# GMAIL_USERNAME: 'Your_Gmail_Username'
# makes 'Your_Gmail_Username' available as ENV["GMAIL_USERNAME"]
GMAIL_USERNAME: 'Your_Gmail_Username'
Set .gitignore
If you have created a git repository for your application, your application root directory should contain a file named .gitignore (it is a hidden file). Be sure your .gitignore file contains:
/config/local_env.yml
This prevents the config/local_env.yml file from being checked into a git repository and made available for others to see.
Rails Application Configuration File
Rails provides the config/application.rb file for specifying settings for various Rails components. We want to set our environment variables before any other settings. Rails provides a config.before_configuration method to do so.
Find the following code at the end of the config/application.rb file:
#Version of your assets, change this if you want to expire all your assets
config.assets.version = '1.0'
and add this code after it:
config.before_configuration do
env_file = File.join(Rails.root, 'config', 'local_env.yml')
YAML.load(File.open(env_file)).each do |key, value|
ENV[key.to_s] = value
end if File.exists?(env_file)
end
The code opens the config/local_env.yml file, reads each key/value pair, and sets environment variables.
The code only runs if the file exists. If the file exists, the code overrides ENV variables set in the Unix shell.
This way each Rails app has its own ENV variables but you can access them all with the same ENV["SOME_KEY"]
Important: Understand that since these files are in .ignore they won't get backed up to version control. But also if you are pushing to your production sever elsewhere they won't get copied over, you'd have to do that manually. And if you are storing passwords or API keys the file is not encrypted in any way so it is not secure if someone gains access to your server. I'm not sure how services like Heroku store their ENV variables that you can set. Probably encrypted in your Rails install using your profile. You will probably want to research that if you choose to go this route.