Rails ActiveStorage: Add the ability to upload photos in background

jobs__delayed_uploader_job.rb

class DelayedUploaderJob < ApplicationJob
  queue_as :default
  attr_reader :model, :attr_name

  def perform(model_klass, id, attr_name)
    @model = model_klass.constantize.find(id)
    @attr_name = attr_name
    upload_photo if tmp_file_data
  end
  
  private

  def upload_photo
    data = { io: file_io, filename: tmp_file_data['name'], content_type: tmp_file_data['content_type'] }
    model.send(attr_name).attach(data)
    remove_tmp_data
    file_io.close
  rescue => e
    Rails.logger.error("#{self.class.name}-> Failed uploading files: #{e.message}")
  end

  def remove_tmp_data
    model[attr_tmp_data] = nil
    model.save!
  end

  def file_io
    @file_io ||= StringIO.new(Base64.decode64(tmp_file_data['body']))
  end

  def tmp_file_data
    @tmp_file_data ||= model[attr_tmp_data]
  end

  def attr_tmp_data
    "tmp_#{attr_name}_data"
  end
end

models__concerns__delayed_file_concern.rb

# frozen_string_literal: true

module DelayedFileConcern
  extend ActiveSupport::Concern
  included do
    def self.delayed_attach(attr_name, required: true)
      tmp_name = "tmp_#{attr_name}".to_sym
      attr_accessor tmp_name
      before_validation { parse_tmp_delayed_file(tmp_name) if send(tmp_name) }
      validates tmp_name, presence: true, unless: ->(o) { o.send(attr_name).blob } if required
      validates attr_name, presence: true, unless: -> (o) { o.send(tmp_name) } if required
      after_save_commit do
        DelayedUploaderJob.perform_later(self.class.name, id, attr_name) if send(tmp_name)
        send("#{tmp_name}=", nil) if send(tmp_name)
      end
    end
  end

  def parse_tmp_delayed_file(tmp_name)
    file = send(tmp_name)
    body = Base64.encode64(file.read)
    if file.respond_to?(:original_filename) # fileUploaded
      content_type = file.content_type
      name = file.original_filename
    else # File.open
      content_type = Marcel::MimeType.for(file)
      name = File.basename(file.path)
    end
    self["#{tmp_name}_data"] = { 'body' => body, 'name' => name, 'content_type' => content_type }
  end
end

models__photo.rb

# == Schema Information
#
# Table name: photos
#
#  id            :integer          not null, primary key
#  created_at    :datetime         not null
#  updated_at    :datetime         not null
#  tmp_file_data :json  <<<< THIS IS REQUIRED WHERE TO SAVE TMP_DATA (tmp_<attr_name>_data)

class Photo < ApplicationRecord
  include DelayedFileConcern
  has_one_attached :file 
  delayed_attach(:file, required: true)
end

# Sample:
photo = Photo.create!(tmp_file: File.open('/my_image.png')) # >> Background job should be scheduled