Some extension seem to require authentication with the app server. If the app server is not created by the CLI, such as an existing server running in a non-javascript language, is there a way to create extension using the Shopify cli, and have the extension integrate with app server?
Basically the app extension document says that: app uses extension should adhere the same authentication requirement. Is that all we need to do to have the extension work with the app server? and are there anyways to customize the authentication endpoints which the extensions should use?
If we couldn't customize the auth endpoint for the extension, we could change our apps to fit the extension's setting. Based on this auth doc, it seems I need to know three endpoints the extension may connect to. Is that all?
