Job with resumable steps

steppable_job.rb

# frozen_string_literal: true

class SubmitWidgetJob < ApplicationJob
  include JobIteration::Iteration

  queue_as :default

  attr_accessor :funding_token, :confirmation_number, :profile_id

  STEPS = [
    "tokenize_card",
    "make_payment",
    "create_profile",
    "change_billing_account",
    "schedule_payments",
    "submit_widget",
  ].freeze

  def build_enumerator(widget, cursor:)
    drop = if cursor.nil?
      0
    else
      index = steps.index(cursor)
      index ? index + 1 : raise(ArgumentError, "Invalid cursor: #{cursor}")
    end

    STEPS.map { [_1, _1] }.drop(drop).to_enum { steps.size - drop }
  end

  def each_iteration(current_step, widget)
    case current_step
    when "tokenize_card"
      tokenize_card(widget)
    when "make_payment"
      make_payment(widget)
    when "create_profile"
      create_profile(widget)
    when "change_billing_account"
      change_billing_account(widget)
    when "schedule_payments"
      schedule_payments(widget)
    when "submit_widget"
      submit_widget(widget)
    end
  end

  # These two methods are public Active Job API, extended by JobIteration, and here we extend them further
  # https://api.rubyonrails.org/classes/ActiveJob/Core.html#method-i-serialize
  def serialize
    super.merge(
      "funding_token" => funding_token,
      "confirmation_number" => confirmation_number,
      "profile_id" => profile_id,
    )
  end

  def deserialize(job_data)
    super
    self.funding_token = job_data["funding_token"]
    self.confirmation_number = job_data["confirmation_number"]
    self.profile_id = job_data["profile_id"]
  end

  private

  def tokenize_card(widget)
    self.funding_token = SecureRandom.hex(16)
    puts "Step 1 sets funding_token to #{funding_token}"
    sleep(1)
  end

  def make_payment(widget)
    self.confirmation_number = SecureRandom.random_number(10)
    puts "Step 2 sets confirmation_number to #{confirmation_number}"
    sleep(1)
  end

  def create_profile(widget)
    self.profile_id = SecureRandom.random_number(1000)
    puts "Step 3 sets profile_id to #{profile_id}"
    sleep(1)
  end

  def change_billing_account(widget)
    puts "Step 4 uses #{funding_token}, #{profile_id}"
    sleep(1)
  end

  def schedule_payments(widget)
    puts "Step 5 uses #{funding_token}, #{profile_id}"
    sleep(1)
  end

  def submit_widget(widget)
    puts "Step 6 uses #{confirmation_number} - done!"
    sleep(1)
  end
end