Service account JSON public

[Rishi M]

Hi all, 

I am trying to publish a web app publicly that uses a service JSON to update the user's settings by calling the web app api. This will be a service json that I have configured to have domain wide delegation. I have also asked for the following permissions: 

In order to change the user's email setItings, I had to impersonate them using the service account json. I have also made the service json compatible with the google workspace marketplace. 

This allowed me to call the url using a get call to the following api and passing the email as a query parameter: 

https://script.google.com/macros/s/<app_id>/exec?email=te...@example.com

I have also configured the app to be admin install only: 

My question is as follows: 

If an admin installs the workspace app, can I use the same service JSON that I have created in this project to access the person's external domain users? How would the domain delegation work? 

Regards, 

Rishi