subscribers_parser.rb

subscribers.each do |subscriber_row|
  user = User.find_by(email: subscriber_row[1])
  if user.nil?
    user = User.create_by_subscribe(
      email: subscriber_row[1],
      first_name: subscriber_row[2],
      last_name: subscriber_row[3]
    )
  end

  subscriptions = Subscription.find(subscriber_row[5])
  if subscriber_row[4] == true
    subscriptions.each do |subscr|
      subscr.subscribe_user(user)
    end
    MailSender.greeting_email(user.id, subscriptions).deliver_now
  else
    subscriptions.each do |subscr|
      subscr.unsubscribe_user(user)
    end
    MailSender.unsubscribe_email(user.id, subscriptions).deliver_now
  end
end