Table of Contents
Envlogic is a simple gem that will help you manage your Ruby application environment. You can use it instead of a really popular solution like this one:
class App def self.env ENV['APP_ENV'] || ENV['RACK_ENV'] || 'development' end end
How does it work?
Well it uses Rails String Inquirer and a bit of magic to resolve the environment key name. It will try to figure out the ENV key on its own, and if it fails it will fallback to development. To use it, just extend your class/module with Envlogic module:
Class MyApp extend Envlogic end MyApp.env #=> 'development' MyApp.env.production? #=> false MyApp.env.development? #=> true
ENV key name resolving
Envlogic will try to guess the key n few steps:
- First it will try to guess the key based on the root directory name of your app. If it is called my_app - the key will be MY_APP_ENV (ENV['MY_APP_ENV'])
- If this fails, it will try to resolve the class/module name in which it is - MyApp will be converted to MY_APP_ENV. It is worth pointing out, that this will also work for namespaced elements, so key for My::SuperApp will be equal to MY_SUPER_APP_ENV
- It will try RACK_ENV as well
- And finally will fallback to development
Where can I use it?
Anywhere outside of Rails app (it has a mechanism like this already built it). Just include this gem in your Gemfile and extend your class with it:
Can I safely replace my string solution with this one?
Yes. The env object (Envlogic::Env) behaves mostly like a typical string, so if you used to compare the env like this:
MyApp.env == 'production'
it will keep working as nothing would happen.
Few simple examples
Based on the app class name:
class MyApp extend Envlogic end ENV['MY_APP_ENV'] = 'production' MyApp.env.production? #=> true MyApp.env.development? #=> false MyApp.env.test? #=> false
Based on the app dir name (/home/apps/super_app):
class App extend Envlogic end ENV['SUPER_APP_ENV'] = 'production' App.env.production? #=> true App.env.development? #=> false App.env.test? #=> false
Based on the namespaced class name:
class Ux::App extend Envlogic end ENV['UX_APP_ENV'] = 'production' Ux::App.env.production? #=> true Ux::App::App.env.development? #=> false Ux::App.env.test? #=> false