Generate translations for activerecord models and columns

i18n_generator.rb

class I18nGenerator
  attr_reader :models, :lang_code

  def initialize(lang_code: :en)
    ignored_tables = %w(schema_migrations)
    @models        = ActiveRecord::Base.connection.tables - ignored_tables
    @models.map! { |model| model.singularize.camelize.constantize }
    @lang_code = lang_code.to_s
  end

  def self.write(*args)
    new(*args).write
  end

  def write
    File.write("config/locales/#{lang_code}.activerecord.yml", i18n_yaml)
  end

  private

  def i18n_yaml
    translations = build_translations
    {
      lang_code => {
        'activerecord' => {
          'models'     => translations[:models],
          'attributes' => translations[:attributes]
        }
      }
    }.to_yaml
  end

  def build_translations
    model_t      = {}
    attributes_t = {}
    models.each do |model|
      underscored = model.to_s.underscore
      model_t.merge!(model_attributes(underscored))
      attributes_t.merge!(underscored => column_attributes(model))
    end
    {
      models: model_t,
      attributes: attributes_t
    }
  end

  # Column translation
  def column_attributes(model)
    attrs = {}
    ignored_columns = %w(id created_at updated_at)
    (model.column_names - ignored_columns).map! do |col|
      attrs.merge!(col => col.humanize.titleize)
    end
    attrs
  end

  # Model translation
  def model_attributes(underscored)
    name = underscored.humanize.titleize
    {
      underscored => {
        'one'   => name,
        'other' => name.pluralize
      }
    }
  end
end