How to make your store without using frameworks from scratch?

Question

css

Specifically, I would like to know how to organize payments on the site? What is the best way to do this? Do I need to connect a payment system? Can it be done without her?
In fact, the task is this: there is a product on the site, there is a site, you just need to write some kind of script for shopping, which I still don’t quite understand how to do, and there are not very many guides on the Internet on this topic, this script must accept payment and return the id of the product, its quantity, the name of the buyer and enter all this into the database upon successful completion of the payment. As a result: a person clicks on a product, indicates the quantity, pays for it, and his purchase data appears in the database. Thanks in advance! I would like to receive a piece of code in the answer or where you can read about it.

Answer 1

Connect the payment aggregator, set up a callback URL where information about a successful payment is sent, and on the side of this script, be sure to check the checksum with each request (to know if the request was really sent by the aggregator or some kind of left-handed attacker) - and if successful, add to the database and perform the necessary actions.

Answer 2

You still write your own framework, for example, you can take separate bundles from Symphony and assemble your own ...