i18nUno is a gem that helps you translate your Rails application into any language you choose. It utilizes the OpenAI API for translations and supports over 100 languages. It's easy to use, and by implementing Git hooks, you can set it up to automatically add new translations or delete old ones via a pre-commit hook.

Add this line to your application's Gemfile:

group :development do
  gem 'i18n_uno'
end

And then execute:

$ bundle install

To use the gem, adhere to the standard procedures outlined in the Rails I18n support guide. While you may organize your folders as you wish, all localization files must be named following the $locale.yml format, such as en.yml for English. The i18n Uno gem will leverage these files to generate new ones for additional languages you wish to include, for instance, es.yml for Spanish, de.yml for German etc.

To utilize the gem, create a file config/initializers/i18n_uno.rb and configure the gem with your OpenAI credentials. Additional settings are available for customization.

I18nUno.configure do |config|
  config.open_ai_key = ENV['OPEN_AI_API_KEY']         # Required: Found at https://platform.openai.com/account/api-keys
  config.default_locale                               # Required: You can set it to I18n.config.default_locale
  config.available_locales                            # Required: I18n.config.default_locale and locales you want to translate to
  config.open_ai_model                                # Optional: Defaults to 'gpt-4-0613'
  config.load_path                                    # Optional: Defaults to 'config/locales'
end

Although changing the Open AI model is supported, it is strongly recommended to stick with gpt-4 models due to the significant quality difference compared to gpt-3 models.

This is example of the initializer

I18nUno.configure do |config|
  config.open_ai_key = ENV['OPEN_AI_API_KEY']
  config.default_locale = :en
  config.available_locales = [:en, :de, :bs]
end

Just run the command from the application folder

bundle exec rake i18n_uno:translate

If new keys are added during development, running the above command again will automatically add and translate these new keys. Key removal is also supported and will be propagated to all language files.

Your default locale serves as the foundational reference for your application's internationalization. Whenever modifications are made to the localization files, executing the previously mentioned gem command will automatically update translations across all other supported languages, adding or removing them as necessary.

To ensure seamless integration of this process, it's advisable to configure a pre-commit hook that triggers the above command. Gem such as lefthook can help with that.

If you are not already supporting internationalization in your rails application you can do that simply by adding locale field to your user model.

  class AddLocaleToUsers < ActiveRecord::Migration
    def change
      add_column :users, :locale, :string, default: 'en'
    end
  end

From there adding you simply need to add before action to app/controllers/authenticated_controller.rb. This would very based on your application but this would be the standard way.

  before_action :set_locale!

  def set_locale!
    I18n.locale = current_user.locale
  end

That would be it, magic of rails will take care of the rest.

Bug reports and pull requests are welcome on GitHub at https://github.com/pythagora-north/i18n_uno.