generate Google access token using service account impersonation in proxy

[priyanka212]

I am creating a proxy where target endpoint will require Google access token for authentication. I want to use service account  impersonation way of generating access token. Need examples/samples or document references to implement the same.

https://cloud.google.com/iam/docs/create-short-lived-credentials-direct#java This one gives 401 error when invoking rest URL