Invoke http cloud function from angular app deployed on App engine in a secured way

Question

I am trying to invoke http cloud function from angular app deployed on App engine. Access required to invoke the cloud function from app engine is done i.e- provided invoke access to the cloud function from the service account associated with the app engine. Added CORS allow access in the cloud function. The official documentation Authenticate function invocation My task requires to generate token programatically and the documentation uses nodejs client library which uses gcloud auth library. I am unable to figure out the workaround of this code for angular application. My question is whether this task is achievable and how can it be achieved?