Gary Illyes from Google said the company is working on putting together "some more thorough do's and don't's" around what e-commerce and other site owners should do with their web sites if the business is temporarily closed due to the coronavirus. But for now, he said just put a message up and disable the shopping cart from checking out.

Gary Illyes posted on Reddit "in the meantime, closing the cart and putting up a message that explains to the user what's happening should be the way to go if you're planning the closure will last a long time."

He said Google is "going to put up some more thorough do's and don't's" around how to handle e-commerce sites closing now. But he said "redirects, 503s, etc, will have unwanted effects on the site from SEO perspective if lasts for more than just a couple days." So try to avoid those if you can.

Make sure to check out the whole thread, it is interesting. And I hope you are not in this situation.

Forum discussion at Reddit.