Microsoft Graph Invoke action addKey

Adds a key credential to a servicePrincipal. This method along with removeKey can be used by a servicePrincipal to automate rolling its expiring keys. As part of the request validation for this method, a proof of possession of an existing key is verified before the action can be performed. ServicePrincipals that don't have any existing valid certificates (i.e.: no certificates have been added yet, or all certificates have expired), won't be able to use this service action. Update servicePrin...