create composer credentials for users in a git private repository?

[mykel]

Hi,

I have a cuestion with my git repository and the users when I do composer. I have a module in a private git repository on my server. This module I sale in my website, and when a user buy it i want to create for this user a credentials (user and password) to he can install the module using composer (composer require vendor/module-name).

How can I create credentials for each user that buys my module so they can only install it. I need to known what steps I have to folow to create a composer module with credentials.