real life searching with ransack including search in field concatation and sorting on virtual columns

ransack.rb

Models

class User
  ransacker :full_name, :formatter => proc {|v| UnicodeUtils.downcase(v) } do |parent|
    Arel::Nodes::NamedFunction.new('LOWER',
      [Arel::Nodes::NamedFunction.new('concat_ws', [' ', parent.table[:first_name], parent.table[:middle_name], parent.table[:last_name]])]
    )
  end
end


Default search order in the controller

  def collection
    if params[:q].nil? 
       params[:q] = {}
       params[:q][:s] = ['created_at desc']
    end

    relation = filtered_collection.includes(:user)
    @search = relation.search(params[:q])

    @results = @search.result(:distinct => true)

    @results = @results.page(params[:page]).per(params[:per_page] || 12)
  end


another controller with custom search

  helper_method :compound_field_name
  def compound_field_name 
    %w(name description ingredients narrative user_full_name).join('_or_') + '_cont' 
  end

   def collection
     if params[:q].nil? 
       params[:q] = {}
       params[:q][:s] = ['created_at desc']
     end

    relation = filtered_collection.includes(:user)
    @search = relation.search(params[:q])

    @results = @search.result(:distinct => true)
    if params[:q] and params[:q][:s] and params[:q][:s].include?("readytime")
      @results = @results.select('*, time_to_cook + time_to_prepare as readytime')
      @results = @results.order('readytime DESC') 
      raise @results.to_sql
    end

    @results = @results.page(params[:page]).per(params[:per_page] || 12)
  end


The form

#filters.well
  = search_form_for @search, url: category_photos_path(current_category), html: { class: ['form-search'] } do |f|
    ul.breadcrumb.pull-left
      li 
        = f.sort_link :readytime, default_order: 'desc'
        span.divider /        
      li 
        = f.sort_link :user_id
        span.divider /
      li 
        = f.sort_link :price, t("Цена"), default_order: 'asc'
        span.divider /
      li 
        = f.sort_link :votes, default_order: 'desc'
        span.divider /
      li 
        = f.sort_link :created_at, default_order: 'desc'

    .input-append.pull-right
      = f.text_field compound_field_name.to_sym,
        placeholder: 'Търсене',
        class: 'span2 search-query',
        autocompleteff: 'off',
        data: { url: polymorphic_path([:texts, current_category, resource_type]), provide: "typeahead" }
      button(type="submit" class="btn btn-red")
        i.icon-search.icon-white

  .clearfix