Setting up fallback locale(s) in Rails 3

I18n(internationalization) and l10n(localization) are topics that are covered superbly by the Rails Guides. The one thing that’s left out is the setup of fallback locales in case something is missing in the currently selected locale (and mark my words - something probably is). Therefore I’m writing this post.

Ideally we’d have i18n-ed and localized everything perfectly, but that’s rarely the case. I’d rather have the users see things from another locale than error messages. So how do we do that in Rails 3? It’s pretty simple actually. There are three fallback options we can select and they all require small changes to the application.rb file.

• fallback to the default locale

# fallback to what's specified in config.i18n.default_locale
config.i18n.fallbacks = true

• fallback to a specified locale

# fallback to en, regardless of what's in config.i18n.default_locale
config.i18n.fallbacks = [:en]

• specify a fallback map (different fallback locales for different locales)

# missing translations of es and fr languages will fallback to english
# missing translations in german will fallback to french
config.i18n.fallbacks = {'es' => 'en', 'fr' => 'en', 'de' => 'fr'}

Well, that’s the gist of it. Happy coding!