In this episode, we tackle a small but important aspect of the cart and checkout flow: preventing users from accessing the checkout page if their cart is empty. You've probably noticed that if you go to the checkout without any items in your cart, it can lead to some errors—like passing a null value to the money helper or just an overall confusing experience for the user.
To clean this up, we create some middleware called RedirectIfCartEmpty. This middleware checks if the cart is empty, and if it is, redirects the user back to the cart page. We discuss how to inject the cart into the middleware, set up the logic by using the isEmpty method we added to our cart implementation earlier, and set the proper redirect route.
Finally, we see how to apply this middleware directly in the checkout controller, so now, if someone tries to hit the checkout page with an empty cart, they get pushed back to where they belong. It's a little improvement, but it helps make the overall flow much smoother and helps us avoid some annoying errors down the road.