Simple hire/fire for Heroku workers

generate_cards_job.rb

class GenerateCardsJob < Struct.new(:params)
  include HerokuWorker

  def perform
    card_number = params[:cards][:number_of_cards]
    card_number.to_i.times do |i|
      card = Card.create!({
        season_id: params[:season_id],
        batch: params[:cards][:batch].parameterize,
        purchasable: params[:cards][:purchasable],
        ordinal: i+1
      })
      p card.errors.messages unless card.valid?
    end
  end

  def success(job)
    fire_worker if ['production', 'staging'].include?(Rails.env)
  end
end

heroku_worker.rb

module HerokuWorker

  def connection
    return @connection if @connection
    raise 'The Heroku API key is mandatory' if ENV['HEROKU_API_KEY'].blank?
    @connection = Heroku::API.new(:api_key => ENV['HEROKU_API_KEY'])
  end

  def app_name
    return @app_name if @app_name
    raise 'The Heroku application name is mandatory' if ENV['HEROKU_APP_NAME'].blank?
    @app_name = ENV['HEROKU_APP_NAME']
  end

  def hire_worker
    begin
      self.connection.post_ps_scale(self.app_name, 'worker', '1')
    rescue Heroku::API::Errors::RequestFailed => e
      ActiveSupport::JSON.decode(e.response.body)['error'] << " #{name}"
    end
  end

  def fire_worker
    begin
      self.connection.post_ps_scale(self.app_name, 'worker', '0')
    rescue Heroku::API::Errors::NotFound => e
      ActiveSupport::JSON.decode(e.response.body)['error'] << " #{name}"
    end
  end
end