online payment system for username/pass

Question

Where should I start looking for a online payment system where once a user pays their account is given full access to the game? Basically exactly like the payment system in minecraft.net . I post in r/programming, because I don't know if I should be using sql database or what. I don't even have the username/password system set up.

Answer 1

It's not that difficult, in theory. I'll leave the implementation up to you, though.

This assumes you have a A. website, B. SQL database, and C. PayPal account:

1. User registers on your website, which creates a record in your database
2. User clicks "buy" link, is sent to PayPal, which contains a reference to their account information on your site.
3. PayPal returns payment confirmation using IPN (Instant Payment Notification). Update the user's database row with the PayPal transaction ID you received to confirm they've paid for the game.

And now you can check that they've paid when they log in to the game client.