UnknownError calling /beta/invitations - microsoft-graph-api

Question

I must be missing something obvious. When posting to the beta API https://graph.microsoft.com/beta/invitations (api ref: https://graph.microsoft.io/en-us/docs/api-reference/beta/api/invitation_post), I get
{
"error": {
"code": "UnknownError",
"message": "",
"innerError": {
"request-id": "e41b0eab-c39c-4cf8-9034-341c81fc722c",
"date": "2017-01-14T19:26:55"
}
}
}
Here's my code:
namespace ConsoleApplication1
{
public class Program
{
static void Main(string[] args)
{
GraphClient g = new GraphClient();
Console.WriteLine(g.SendPost(g.authContext, g.credential).Result);
}
}
public class GraphClient
{
public AuthenticationContext authContext;
public ClientCredential credential;
public GraphClient()
{
this.authContext = new AuthenticationContext("https://login.microsoftonline.com/MYTENANT.onmicrosoft.com");
this.credential = new ClientCredential("MYCLIENTID", "MYCLIENTSECRET");
}
public async Task<string> SendPost(AuthenticationContext authContext, ClientCredential credential)
{
AuthenticationResult result = await authContext.AcquireTokenAsync("https://graph.microsoft.com", credential);
HttpClient http = new HttpClient();
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Post, "https://graph.microsoft.com/beta/invitations");
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", result.AccessToken);
request.Content = new StringContent("{\"invitedUserEmailAddress\": \"MYEMAIL#MYDOMAIN.COM\",\"inviteRedirectUrl\": \"https://MYWEBSITE.COM\"}", Encoding.UTF8, "application/json");
HttpResponseMessage response = await http.SendAsync(request);
return await response.Content.ReadAsStringAsync();
}
}
}
Thanks! I can do other /beta commands just fine. For example GETting https://graph.microsoft.com/beta/users returns a user list in my tenant, as expected.
-Dan

Answer 1

Based on the logs, you are receiving a 401 error response, which means that the caller was not granted the required permissions to call the API. You'll need to follow the guidance here: https://graph.microsoft.io/en-us/docs/api-reference/beta/api/invitation_post which indicates that you need Directory.ReadWrite.All or User.ReadWrite.All (although I'm not sure the latter one works or is available right now).
We've also filed a bug to fix this error message (sorry about this - we do need to do much better here).
Hope this helps,