The unique ID for the customer's Google Workspace account. In case of a multi-domain account, to fetch all groups for a customer, use this field instead of domain. You can also use the my_customer alias to represent your account's customerId. The customerId is also returned as part of the Users resource. You must provide either the customer or the domain parameter.
Immutable ID of the role assignment.
The request body must be empty.
If successful, the response body contains an instance of RoleAssignment.