Configy

Configy creates a config object based on a YAML file.

Summary

It allows you to have a file (config/app_config.yml) with application configuration parameters. It should have a "common" section with all parameters along with default values and can also contain a section for each application environment (development, test, production, or your custom one). The values from the current environment section will override the values in the "common" section.

If a developer needs his own specific values for his working copy, he can simply create a config/app_config.local.yml file and override any value there, again having a "common" section and a section for each environment.

The files are parsed with ERB. Configy also checks for file modifications so you don't have to restart the server to pick up new values on production.

Example

config/app_config.yaml:

common:
  appname: "My App"
  caching:
    enabled: false
  facebook:
    appid: 123
    secret: abc

production:
  caching:
    enabled: true
    default_max_age: <%= 1.hour %>
  facebook:
    appid: 456
    secret: def

Assuming ENV['RACK_ENV'] == "production"

Configy.create("app_config")      # Creates AppConfig constant
AppConfig.caching.enabled?        # => true
AppConfig.caching.default_max_age # => 3600
AppConfig.appname                 # => "My App"
AppConfig.facebook.appid          # => 456

# Or with less magic:

config = Configy::Base.new("app_config", "production", Rails.root.join("config") )
config.caching.enabled? # => true
config['caching']['enabled'] # => true
...

Features

Sections

Configy assumes that you are breaking your configurations into sections. It will automatically detect which section to use. It looks for an environment variable in following order

ENV['CONFIGY_ENV'], ENV['RAILS_ENV'], ENV['RACK_ENV']

and assumes you have a section in your YAML file named the same way, for example:

development:
  facebook_app_id: 123456
  facebook_secret: abcdef
production:
  facebook_app_id: 456789
  facebook_secret: defghi

If none of the environment variables above are set, it defaults to development.

Common section

If you have a section named common, that section will provide default values for all other sections. Under the hood, Configy deep merges the environment section into the common section. For example:

common:
  newrelic_enabled: true
  newrelic_key: "123456"

development:
  newrelic_enabled: false

staging:

production:

All environments will inherit the common section configurations, and the development environment overrides the newrelic_enabled setting.

Nested configs

You can nest configs as much as you like.

common:
  facebook:
    app:
      id: 123

AppConfig.facebook.app.id # => 123

Local config file

If you have a config file named config/app_config.yml and another config file named config/app_config.local.yml, the local config file's configurations will override the main config file's configurations.

ERB

Config files are parsed as ERB templates

Auto reloading

Configy will check the config file's mtime to see if it needs to reload it's configuration. You can disable this with Configy.cache_config = true

Rails generator

Configy provides an [optional] generator.

rails g configy:install

Authors

• Gabe Varela
• Ben Marini
• Chip Miller
• Bram Swenson
• Jeremy Ruppel

History

The Configy gem based on the AppConfig plugin which was evolved from the original plugin by Eugene Bolshakov, eugene.bolshakov@gmail.com, http://www.taknado.com

The plugin is based on the idea described here: http://kpumuk.info/ruby-on-rails/flexible-application-configuration-in-ruby-on-rails/lang-pref/en/