gcp_sql_user module: add Cloud IAM users to the instances

[iungoron]

SUMMARY

Ability to add an existing IAM principal as user on the Cloud SQL instances.

ISSUE TYPE

• Feature Idea

COMPONENT NAME

google.cloud.gcp_sql_user module

ADDITIONAL INFORMATION

Actually only standard MySQL users with built-in authentication can be created.
There should be the possibility to add a Cloud IAM principal for the authentication to the MySQL user
And also add the possibility to assign privileges ad the community.mysql.mysql_user module does with the priv parameter

For example:

• allow principal email as name of the user
• specify the type of authentication
• assign privileges

- name: create a user
     google.cloud.gcp_sql_user:
       name: test-user@test_project.iam.gserviceaccount.com
       authentication: builtin / iam
       host: x.x.x.x
       password: secret-password
       instance: "{{ instance }}"
       project: test_project
       auth_kind: serviceaccount
       service_account_file: "/tmp/auth.pem"
       priv:
         'mydb1.*': 'ALL'
         'mydb2.*': 'SELECT'
       state: present

References:

https://docs.ansible.com/ansible/latest/collections/google/cloud/gcp_sql_user_module.html
https://docs.ansible.com/ansible/latest/collections/community/mysql/mysql_user_module.html#ansible-collections-community-mysql-mysql-user-module
https://cloud.google.com/sql/docs/mysql/add-manage-iam-users
https://github.com/GoogleCloudPlatform/cloud-sql-jdbc-socket-factory