redmine/app/views/versions/index.api.rsb

api.array :versions, api_meta(:total_count => @versions.size) do
  @versions.each do |version|
    api.version do
      api.id version.id
      api.project(:id => version.project_id, :name => version.project.name) unless version.project.nil?

      api.name            version.name
      api.description     version.description
      api.status          version.status
      api.due_date        version.effective_date
      api.sharing         version.sharing
      api.wiki_page_title version.wiki_page_title

      render_api_custom_values version.visible_custom_field_values, api

      api.created_on version.created_on
      api.updated_on version.updated_on
    end
  end
end