“undefined method” when calling helper method from controller in Rails

Question

Does anyone know why I get

undefined method `my_method\' for #

when I call my_method(\"string\") from withi

Answer 1

though its not a good practice to call helpers in controller since helpers are meant to be used at views the best way to use the helpers in controller is to make a helper method in application_controller and call them to the controller,
but even if it is required to call the helper in a controller
then Just include the helper in the controller

class ControllerName < ApplicationController
  include HelperName
  ...callback statements..

and call the helper methods directly to the controller

 module OffersHelper
  def generate_qr_code(text)
    require 'barby'
    require 'barby/barcode'
    require 'barby/barcode/qr_code'
    require 'barby/outputter/png_outputter'
    barcode = Barby::QrCode.new(text, level: :q, size: 5)
    base64_output = Base64.encode64(barcode.to_png({ xdim: 5 }))
    "data:image/png;base64,#{base64_output}"
  end

Controller

class ControllerName < ApplicationController
include OffersHelper

def new
  generate_qr_code('Example Text')
end
end

hope this helps !