Invitations are placeholders for rolemap objects. You cannot create a rolemap directly because, sometimes, user approval is required. Invitations are sent to users via email and, once accepted, create a rolemap on the object they were invited to with the requested role.
Create an Invitation

Example Request Body

"invitation": {
"role_name": "Creator"
If a role_name is not provided, or is invalid, the default role will be used.