We are close to get Ansible to work with OS Login through integrated inventories.
This is based somehow on https://alex.dzyoba.com/blog/gcp-ansible-service-account/ Important read: https://docs.ansible.com/ansible/latest/scenario_guides/guide_gce.html#migration-guides
** Things to be done **
The ansible_user in the group_vars should be sa_ + the output of the make setup.
The ssh key, can be added as dzyoba's blog, although we can use the default's PRIVKEY=${HOME}/.ssh/google_compute_engine. Use ssh-add ${HOME}/.ssh/google_compute_engine.
make ping fails.
make odyssey-conf gather facts, but fails with error.
The idea is to find a way to automatically get the ansible_user and use the default credentials or enable the ssh keys.