Azure Ad B2C Authentication EmailMethod via Graph Api select

I’m trying to call multiple attributes via the graph api including the authentication email methods.
However when i try to select the authentication attribute, i always receive a null value.
Calling it directly works fine, however that way i need to call the graph api a second time to get all other attributes.

My Call looks something like this.

await _graphClient.Users[userId].Request()
        .Select($"displayName,authentication,otherMails,identities).GetAsync();

This way the authentication attributes just shows a null value,
even though the UserAuthenticationMethod.ReadWrite.All is set for the api

Using this works just fine

await _graphClient.Users[userId].Authentication
        .EmailMethods["3ddfcfc8-9383-446f-83cc-3ab9be4be18f"].Request().GetAsync();

however my goal would be to get it in one fell swoop, without the need for a second call.

>Solution :

authentication is not a property but a relationship, so you can’t specify authentication in .Select(...).

Relationships can be specified in .Expand(...) like

await _graphClient.Users[userId].Request()
    .Select($"displayName,otherMails,identities")
    .Expand("authentication").GetAsync();

But according to the documentation authentication doesn’t support $expand and the endpoint GET /users/{user_id} supports only $select.

So it’s not possible to achieve your goal by one call