Private scope part of photo_galleries_controller.rb

gistfile1.rb

private
    # Use callbacks to share common setup or constraints between actions.
    def set_photo_gallery
      @photo_gallery = PhotoGallery.find(params[:id])
    end

    # Never trust parameters from the scary internet, only allow the white list through.
    def photo_gallery_params
      # add :photos param below
      params.require(:photo_gallery).permit(:description,:photos)
    end
   
   # new method added below
    def save_photos images
      if images
        images.each_value { |image|
        @photo_gallery.photos.create(image: image)
        }
      end
    end

    def compare_photos images
      if images.presence
        images.each { |key,new_image|
          if @photo_gallery.photos[key.to_i].presence 
            @photo_gallery.photos[key.to_i].image = new_image
            @photo_gallery.photos[key.to_i].save
          else
            @photo_gallery.photos.create(image: new_image)
          end
        }
      end
    end