I'm building an online store for a client using Next.js and Supabase, and they want customers to place cash-on-delivery orders without creating an account or signing in. I'm trying to understand the typical implementation: are guest orders saved directly to the database, and how are carts or sessions tracked? I'm also concerned about bots or abusive users submitting large numbers of fake orders. What's a safe way to design the database access, rate limiting, CAPTCHA or honeypot checks, and phone-number verification for this type of checkout?
3 Answers
The database itself can handle guest orders, but you need to protect the write path. Add server-side validation, enforce maximum quantities and reasonable field lengths, and use Supabase Row Level Security so public clients cannot freely insert or read order records. Keep privileged database credentials on the server only. For tracking, use a random cart or checkout token rather than relying on an email address or predictable numeric ID.
Guest checkout is usually handled by creating a temporary cart or session ID in a cookie or server-side session. When the customer submits the form, your backend validates the details and inserts an order row containing the products, quantity, delivery information, phone number, payment method, and an initial status such as `pending`. The browser should never be allowed to insert arbitrary orders directly into Supabase; send the request through a protected server endpoint or server action that validates and creates the order.
Fake orders are usually the bigger problem with cash on delivery. Rate-limit checkout attempts by IP and by a device or session identifier, add a honeypot field and CAPTCHA when behavior looks suspicious, and consider verifying the phone number before confirming the order. You can also flag repeated orders using the same phone, address, or device for manual review instead of treating every submission as a real sale.
You can implement basic limits in middleware or an API route, but use a shared store such as Redis or an edge-compatible rate-limiting service if the app runs across multiple instances. An in-memory counter alone will reset whenever the server restarts.
That makes sense. I was mainly unsure whether guest orders needed a user account, but using a session ID seems like the right approach.