I am trying to implement a server side push provisioning with Google Pay using Spring Boot and implement my own Token service provider that generates the OPC, and I am not really sure how the process works. What I understood is that I need to get CardInfo from the Android client and generate an OPC(Opaque payment card) token and then send it to Google Pay to use it to generate some token that It will store in its wallet and GPay can then push it to the android client via the integrated SDK once it's generated.
1st question : Is this really the right process ?
2nd question : Where can I get the MASTERCARD_PUBLIC_KEY or Visa's that will be used in the encryption process to generate the OPC ?
Also I faced a confusion when I wanted to think about the way I'm gonna retrieve the tokenized cards from GPay, It's asking me to provide it with the TSP(token service provider) which is my backend spring Boot app which confused me because I didn't see how could I pass it.
If anyone has already implemented it I would really appreciate any help or code sample