是否可以进行网页抓取？ /合法吗？ [关闭]

I’m trying to scrape https://www.johnlewis.com/ (shopping site). I want to check to see if an item is in stock using the beautiful-soup and requests library in python. I’m checking to see if there is an “out of stock” button (if not then it is in stock). Is it ok if I do this? I’m scraping every 30 seconds and running continuously on heroku. Help is greatly appreciated.