gistfile1.rb

class CategoryXls
  require 'spreadsheet'
  def self.read file_path
    Spreadsheet.open(file_path) do |book|
      book.worksheets.each do |ws|
        0.upto ws.last_row_index do |index|
          row = ws.row(index)
          yield ws, row
        end
      end
    end
  end

  def self.import(file)
    raise ArgumentError, 'missing required argument file' unless file.present? 
    
    read(file) do |sheet, row|
      load_category(row[0].to_s)
      load_subcategory(row[1].to_s, @category.id)
    end
  end

  def self.load_category(row_1)
    name_category = row_1
    unless name_category.empty?
      @category = ItemCategory.find_or_create_by(:name => name_category)
      puts "Categories: #{@category.name}"  
    end 
  end

  def self.load_subcategory(row_2, id_category)  
    name_subcategory = row_2
    
    unless name_subcategory.empty?
      @item_category_as_category = ItemCategory.categories.where(
                                  :name => name_subcategory).first
      
      if !@item_category_as_category.nil?
        subcategories = @item_category_as_category.update_attributes(
                        item_category_id: id_category)
      else
        subcategories = ItemCategory.
        create_subcategory!(name_subcategory, id_category) 
        
      end

    end
  end

end