How can i use APISetu to get documents from digilocker

I am trying to integrate digilocker apis in my program where i am confused about lots of things, I need stepwise details to use digilocker to perform the following tasks:

  • First open digilocker page for user registration
  • When user registers ask consent for required documents (Aadhar and driving license)
  • After that collect the document and store in my database and in website give a success response

I am successful in first two tasks using the generated api key from api setu partners and i am also sure that it is calling a callback api after the consent is given. But i have no idea from where that callback api is coming. I can also change the api but i am not sure how can i alter it to get the desired files.