Owners of APPUiO Cloud Organizations or Billing Entities need the ability to invite users to their organization or billing entity.
They can do so by creating an invitation object in the APPUiO Control API or be using the APPUiO Portal.
Since new users do not have a user name yet, the invitation object is not linked to a user object. The first user claiming the invitation will be linked to the invitation object. To make an invitation discoverable, the invitation contains an email address to notify the user about the invitation.
The authentication and sign up is handled by the IDP where users can create a new account using social login or email.
In order to allow users to sign up, the IDP needs to be configured to allow sign up. See IDP requirements The IdP should provide means to on-board new users to APPUiO Cloud.
See APPUiO Control API: Invitation for the APPUiO Control API specification.