app.rb

def use_case(name)
  Services.use_case name
end

def gateway(name)
  Services.gateway name
end

def report_to_sentry(exception)
  Sentry.capture_exception(exception) if defined?(Sentry)
end

class QueueWorker
  def start!
    until interrupted?
      sleep 1

      register_signal_handlers
      set_postgres_connection
      pull_queues
    end
    completed_batch
  ensure
    shutdown
  end

private

  def pull_queues
    Helper::Toggles.enabled?("data_warehouse_consumes_queues", default: true) do
      pull_use_case = use_case :pull_queues
      pull_use_case.execute from_recovery_list: true
      pull_use_case.execute from_recovery_list: false
    end
  end

  def register_signal_handlers
    trap("INT") { interrupt }
    trap("TERM") { interrupt }
  end

  def set_postgres_connection
    if ENV["DATABASE_URL"].nil?
      raise ArgumentError, "Please set DATABASE_URL"
    end

    ActiveRecord::Base.establish_connection(ENV["DATABASE_URL"])
  end

  def interrupt
    @interrupted = true
    puts "Completing import of current batch after interrupt received"
  end

  def completed_batch
    puts "Completed import of current batch"
  end

  def interrupted?
    @interrupted
  end

  def shutdown
    puts "Shutting down queue worker"
    exit(0)
  end
end

QueueWorker.new.start!