RoR. How to properly handle an error coming from the API?

Question

API

Hello. I have a vk_tracks controller, it has an add method, This method adds an audio recording to the user. Sometimes, with a large number of requests, captcha crashes and this captcha needs to be processed. For vk api I use this gem: https://github.com/7even/vkontakte_api
All requests are made via ajax.
Here is the code:

def add
    @vk_track = VkTrack.find(params[:id])
    if params[:captcha]
      id = @vk.audio.add(audio_id: @vk_track.vk_id, owner_id: @vk_track.owner_id, captcha_sid: params[:captcha_sid], captcha_key: params[:captcha])
      respond_to do |format|
        format.html {}
        format.js   {}
      end
    else
      begin
        @vk.audio.add(audio_id: @vk_track.vk_id, owner_id: @vk_track.owner_id)

        respond_to do |format|
          format.html {}
          format.js   {}
        end
      rescue VkontakteApi::Error => @e
        if @e.error_code == 14
          respond_to do |format|
            # тут мы просто выводим модальное окно а в нем картинку с капчей и форму
            format.js { render :file => "vk_tracks/captcha.js.erb" }
          end
        else
          raise
        end
      end
    end
  end

I'm new to ruby ​​and can't figure out how to do it right. Now, when captcha is triggered, a modal window pops up with captcha and a form. This form submits data to the same controller and method. Is there an easier way? And what is the best way to process captcha.

Answer 1

def add
  vk_track = VkTrack.find(params[:id])
  
  @vk.audio.add(audio_params(vk_track))
rescue VkontakteApi::Error => e
  raise e unless e.error_code == 14

  respond_to do |format|
    # Старайтесь не делать ваши вьюхи зависимыми от инстанс-переменных (@var)
    # По возможности, старайтесь использовать partials и передавать
    # зависимости явным образом
    # file: app/views/controller_name/_captcha.js.erb
    # в нем будет доступна переменная exception
    format.js { render partial: 'captcha', exception: e }
  end
end

def audio_params(vk_track)
  {
    audio_id: vk_track.vk_id,
    owner_id: vk_track.owner_id
  }.merge(captcha_params)
end

def captcha_params
  return {} unless params[:captha]

  {
    captcha_sid: params[:captcha_sid],
    captcha_key: params[:captcha]
  }
end

To be honest, I did not check the functionality of the code, but it seems that there should not be any problems.