CSVがステキに見える！

controller.rb

    params[:upload_file].tap do |upload_file|
      file = upload_file.tempfile.tap
      master_class = upload_file.original_filename.sub('.csv', '').classify
      master_class.delete_all
      csv = CSV.parse(file.read, headers: true)
      csv.each do |row|
        row = row.to_hash.with_indifferent_access
        row.delete(nil)
        if row[:id]
          master_class.new(row).tap {|record|
            record.id = row[:id]
          }.save!
        end
      end
    end

csv.rb

require 'csv'    

csv_text = File.read('...')
csv = CSV.parse(csv_text, :headers => true)
csv.each do |row|
  row = row.to_hash.with_indifferent_access
  Moulding.create!(row.to_hash.symbolize_keys)
end