When intergrating Active Storage and Google Cloud Storage, is the "project" key in storage.yml really necessary?

Question

Below is an example of GCS settings in storage.yml :

google:
  service: GCS
  credentials: <%= Rails.root.join("path/to/keyfile.json") %>
  project: ""
  bucket: ""

Since there is already project_id inside credentials , what is the purpose of project ? Does this make any difference if I omit this key?

Answer 1

This seems to be a requirement from Active Storage as mentioned here . Most likely, both parameters are needed due to the fact that you could create a service account in one project, and give it access to a different one. If you did this, the credentials of the service account would have the origin project, however, you could access the second project with the same file.