RailsConfig

Summary

RailsConfig helps you easily manage environment specific Rails settings in an easy and usable manner

Features

• simple YAML config files
• config files support ERB
• config files support inheritance
• access config information via convenient object member notation

Compatibility

• Rails 3.x and 4.x
• Padrino
• Sinatra

For older versions of Rails and other Ruby apps, use AppConfig.

Installing on Rails 3 or 4

Add this to your Gemfile:

gem "rails_config"

Installing on Padrino

Add this to your Gemfile:

gem "rails_config"

in your app.rb, you'll also need to register RailsConfig

register RailsConfig

Installing on Sinatra

Add this to your Gemfile:

gem "rails_config"

in your app, you'll need to register RailsConfig. You'll also need to give it a root so it can find the config files.

set :root, File.dirname(__FILE__)
register RailsConfig

It's also possible to initialize it manually within your configure block if you want to just give it some yml paths to load from.

RailsConfig.load_and_set_settings("/path/to/yaml1", "/path/to/yaml2", ...)

Customizing RailsConfig

You may customize the behavior of RailsConfig by generating an initializer file:

rails g rails_config:install

This will generate config/initializers/rails_config.rb with a set of default settings as well as to generate a set of default settings files:

config/settings.yml
config/settings/development.yml
config/settings/production.yml
config/settings/test.yml

Accessing the Settings object

After installing this plugin, the Settings object will be available globally. Entries are accessed via object member notation:

Settings.my_config_entry

Nested entries are supported:

Settings.my_section.some_entry

Alternatively, you can also use the [] operator if you don't know which exact setting you need to access ahead of time.

# All the following are equivalent to Settings.my_section.some_entry
Settings.my_section[:some_entry]
Settings.my_section['some_entry']
Settings[:my_section][:some_entry]

If you have set a different constant name for the object in the initializer file, use that instead.

Common config file

Config entries are compiled from:

config/settings.yml
config/settings/#{environment}.yml
config/environments/#{environment}.yml

config/settings.local.yml
config/settings/#{environment}.local.yml
config/environments/#{environment}.local.yml    

Settings defined in files that are lower in the list override settings higher.

Reloading settings

You can reload the Settings object at any time by running Settings.reload!.

Reloading settings and config files

You can also reload the Settings object from different config files at runtime.

For example, in your tests if you want to test the production settings, you can:

Rails.env = "production"
Settings.reload_from_files(
  Rails.root.join("config", "settings.yml").to_s,
  Rails.root.join("config", "settings", "#{Rails.env}.yml").to_s,
  Rails.root.join("config", "environments", "#{Rails.env}.yml").to_s
)

Environment specific config files

You can have environment specific config files. Environment specific config entries take precedence over common config entries.

Example development environment config file:

#{Rails.root}/config/environments/development.yml

Example production environment config file:

#{Rails.root}/config/environments/production.yml

Developer specific config files

If you want to have local settings, specific to your machine or development environment, you can use the following files, which are automatically .gitignored :

Rails.root.join("config", "settings.local.yml").to_s,
Rails.root.join("config", "settings", "#{Rails.env}.local.yml").to_s,
Rails.root.join("config", "environments", "#{Rails.env}.local.yml").to_s

Adding sources at Runtime

You can add new YAML config files at runtime. Just use:

Settings.add_source!("/path/to/source.yml")
Settings.reload!

This will use the given source.yml file and use its settings to overwrite any previous ones.

One thing I like to do for my Rails projects is provide a local.yml config file that is .gitignored (so its independent per developer). Then I create a new initializer in config/initializers/add_local_config.rb with the contents

Settings.add_source!("#{Rails.root}/config/settings/local.yml")
Settings.reload!

Note: this is an example usage, it is easier to just use the default local files settings.local.yml, settings/#{Rails.env}.local.yml and environments/#{Rails.env}.local.yml for your developer specific settings.

Embedded Ruby (ERB)

Embedded Ruby is allowed in the configuration files. See examples below.

Accessing Configuration Settings

Consider the two following config files.

#{Rails.root}/config/settings.yml:

size: 1
server: google.com

#{Rails.root}/config/environments/development.yml:

size: 2
computed: <%= 1 + 2 + 3 %>
section:
  size: 3
  servers: [ {name: yahoo.com}, {name: amazon.com} ]

Notice that the environment specific config entries overwrite the common entries.

Settings.size   # => 2
Settings.server # => google.com

Notice the embedded Ruby.

Settings.computed # => 6

Notice that object member notation is maintained even in nested entries.

Settings.section.size # => 3

Notice array notation and object member notation is maintained.

Settings.section.servers[0].name # => yahoo.com
Settings.section.servers[1].name # => amazon.com

Working with Heroku

Heroku uses ENV object to store sensitive settings which are like the local files described above. You cannot upload such files to Heroku because it's ephemeral filesystem gets recreated from the git sources on each instance refresh.

To use rails_config with Heroku just set the use_env var to true in your config/initializers/rails_config.rb file. Eg:

RailsConfig.setup do |config|
  config.const_name = 'AppSettings'
  config.use_env = true
end

Now rails_config would read values from the ENV object to the settings. For the example above it would look for keys starting with 'AppSettings'. Eg:

ENV['AppSettings.section.size'] = 1
ENV['AppSettings.section.server'] = 'google.com'

It won't work with arrays, though.

To upload your local values to Heroku you could ran bundle exec rake rails_config:heroku.

Contributing

Bootstrap

$ appraisal install

Running the test suite

$ appraisal rspec

Authors

• Jacques Crocker
• Fred Wu
• Piotr Kuczynski
• Inherited from AppConfig by Christopher J. Bottaro

License

RailsConfig is released under the MIT License.