Back-end routes complete for adding product to cart
If req.user exists (i.e. someone is logged in): finds or creates pending order, finds or creates order detail (if same product already in cart, updates price/quantity accordingly).
if req.user does not exist (i.e. guest checkout): checks req.session for cart, if undefined then creates order and sets req.session.cart equal to this order. updates order details.
Back-end routes complete for adding product to cart If req.user exists (i.e. someone is logged in): finds or creates pending order, finds or creates order detail (if same product already in cart, updates price/quantity accordingly). if req.user does not exist (i.e. guest checkout): checks req.session for cart, if undefined then creates order and sets req.session.cart equal to this order. updates order details.