Store translations in your PG database as HSTORE, JSON or JSONB.

To use this gem in your rails app simply add the following to your Gemfile:

gem 'pg_translatable'

To translate your model's fields you must call the translate method:

# app/models/post.rb

class Post < ActiveRecord::Base
  translate :title, :content

  ...

end

These fields will be translated to all locales that you have defined in config.i18n.available_locales.

E.g. the following configuration would store translations for english, german, french and spanish:

# config/application.rb

module TestApp
  class Application < Rails::Application
    config.i18n.default_locale = :en
    config.i18n.available_locales = [:en, :de, :fr, :es]
  end
end

When you call the field's name in singular it will return the value for the current locale, that is the locale defined in I18n.locale. So for the above example, if my current locale was set to :fr calling title would return the title in french.

When you call the field's name in plural it will return a hash containing all translations. For the above example, calling titles would return a hash containing all translations.

Additionally a per locale getter and setter will be defined for each field. For the above example the following getters and setters would be generated: title_en, title_de, title_fr, title_es, content_en, content_de, content_fr, content_es

NOTE: If it happens that the singular and plural of a given field are the same then the plural will get suffixed with _translations.

E.g. If there was a field called news it's getters and setters would be news for the current translation and news_translations for the translations hash.

If you want to format the output of a getter method then you can just redefine the formatter method for any field.

E.g. if you wanted your content's translations to be returned in reverse:

# app/models/post.rb

class Post < ActiveRecord::Base
  translate :title, :content, :price

  private

  def content_formatter(value)
    value.to_s.reverse
  end
end

NOTE: Only getters pass data through formatters, setters save data given to them as is.

To better integrate translations with strong parameters a convenience method will be defined for each field, it will just be suffixed with _fields.

For the above example you could do the following:

# app/controllers/posts_controller.rb

class PostsController < ApplicationController

  ...

  private

  def post_params
    params.require(:post).permit(
      *Post.title_fields,
      *Post.content_fields
    )
  end

  ...

end

There is no practical solution for validating this kind of data. My suggestion is to write custom validator classes.

Here is an example validator.

# app/validators/translation_present_validator.rb
class TranslationsPresentValidator < ActiveModel::EachValidator
  def validate_each(record, attribute, _value)
    languages =
      record.try(:validate_translations_for_languages) ||
      I18n.available_locales

    languages.each do |locale|
      next if record.send("#{attribute}_#{locale}").present?
      record.errors.add(
        "#{attribute}_#{locale}".to_sym, :translation_missing
      )
    end
  end
end

# app/models/post.rb
class Post < ActiveRecord::Base
  translate :title

  validates :title, translation_present: true
end

After checking out the repo, make sure you have a Postgres database server running on your machine then move to the spec/test_app directory and run the following commands:

rake db:create
rake db:migrate

Open an issue here or do the following:

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request