How to get an access token without the NUKI login prompt? (code only)

Hello Nuki team,

Let me try to explain my problem:
I have my backend server API, which currently sends out NUKI entrance pin-codes to the user whenever they want to access my apartment.
However, I do not like the fact the I need to manually create the entrance pin-codes in NUKI app and then add those pin-codes to my DB (double work). I want this process to be automated, meaning I do not want to create entrance pin-codes and store it to my DB every day.

Expected solution
I want to setup my backend server API, so that it automatically generates one time entrance pin-codes for the visitors of my apartment → meaning I won’t need to create those pin-codes manually. The solution I imagined was that I will use NUKI API to CRUD the pin-codes from my backend-server as described here Web API Example: Manage PIN-Codes for your Nuki Keypad.

NUKI API problem:
However, the problem rises when I try to get an access_token described in your documentation here, Web API Authentication. It seems like it is not possible to get the access_token pragmatically, meaning it is not possible to get the AUTHORIZATION_CODE without manually logging in the account via the NUKI auth user interface.

Final question:
My final question is; is it possible to get the authorization_code/access_token in some pragmatic way (only from code), so that I will not be prompted to manually fill-out the NUKI’s auth login?

From what I understood, it should be possible via ApiKey described in Swagger UI, but it is still unclear to me how. Btw, I’m using NUKI keypad, Smartlock and NukiBridge.

Thanks for the help.

Kind regards,
Martin