Azure Mobile Services LoginAsync method not working with Microsoft Auth Token - oauth-2.0

Question

I have successfully been able to get an access_token (or authenticationToken for Microsoft tokens) using the client side authentication in my Xamarin forms App. I am able to get further user information (email, name, etc.) using the same access token. Now, when I try to pass that token to my Azure Mobile Service backend, I get a 401 error.
Here is my code:
private async System.Threading.Tasks.Task<string> MSGetUserInfo(Account account)
{
// Reference: http://graph.microsoft.io/en-us/docs/overview/call_api
// Note that Microsoft don't recognize the access_token header entry, but rely instead on an Authorization header entry
var client = new HttpClient();
var userInfoRequest = new HttpRequestMessage()
{
RequestUri = new Uri("https://graph.microsoft.com/v1.0/me"),
Method = HttpMethod.Get,
};
// Add acccess Bearer
userInfoRequest.Headers.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", account.Properties["access_token"]);
using (var response = await client.SendAsync(userInfoRequest).ConfigureAwait(false))
{
if (response.IsSuccessStatusCode)
{
Models.User user = new Models.User();
var responseString = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
var jobject = JObject.Parse(responseString);
var userName = (string)jobject["userPrincipalName"];
// Check username is valid
if (String.IsNullOrEmpty(userName))
{
throw new Exception("Username was not set for authenticated user");
}
else
user.ProviderLoginId = userName;
var userDisplayName = (string)jobject["displayName"];
// Replace display name if invalid
if (String.IsNullOrWhiteSpace(userDisplayName))
{
userDisplayName = userName;
}
else
user.Name = userDisplayName;
var userEmail = (string)jobject["mail"];
// Replace email if invalid
if (String.IsNullOrWhiteSpace(userEmail))
{
userEmail = userName;
}
else
user.Email = userEmail;
Valufy.App.currentUser = user;
}
else
{
throw new Exception("OAuth2 request failed: " + await response.Content.ReadAsStringAsync().ConfigureAwait(false));
}
}
return "success";
}
The above code snippet works in getting my user details. Now when I try to use the same token in the subsequent call, I get a 404:
public async Task<bool> Authenticate(string token)
{
string message = string.Empty;
var success = false;
JObject objToken = new JObject();
//objToken.Add("access_token", token); //for facebook and google
objToken.Add("authenticationToken", token); //for microsoft
try
{
// Sign in with Facebook login using a server-managed flow.
if (user == null)
{
//ProviderAuth("MICROSOFT");
user = await syncMgr.CurrentClient
.LoginAsync(MobileServiceAuthenticationProvider.MicrosoftAccount, objToken);
if (user != null)
{
success = true;
message = string.Format("You are now signed-in as {0}.", user.UserId);
}
}
}
catch (Exception ex)
{
message = string.Format("Authentication Failed: {0}", ex.Message);
}
// Display the success or failure message.
// await new MessageDialog(message, "Sign-in result").ShowAsync();
return success;
}
Is there something that I am doing wrong? Any and all assistance is appreciated.

Answer 1

According to your description, I followed this Git sample about Microsoft Graph Connect Sample for UWP (REST). I could get the access_token and it could work as expected with Microsoft Graph API (e.g. Get a user). But when I use this access_token as the authenticationToken token object for MobileServiceClient.LoginAsync, I could also get 401 Unauthorized.
Then I checked the managed client for Azure Mobile Apps about Authenticate users. For Client-managed authentication flow, I found that the official code sample about using Microsoft Account is working with Live SDK as follows:
// Request the authentication token from the Live authentication service.
// The wl.basic scope should always be requested. Other scopes can be added
LiveLoginResult result = await liveIdClient.LoginAsync(new string[] { "wl.basic" });
if (result.Status == LiveConnectSessionStatus.Connected)
{
session = result.Session;
// Get information about the logged-in user.
LiveConnectClient client = new LiveConnectClient(session);
LiveOperationResult meResult = await client.GetAsync("me");
// Use the Microsoft account auth token to sign in to App Service.
MobileServiceUser loginResult = await App.MobileService
.LoginWithMicrosoftAccountAsync(result.Session.AuthenticationToken);
}
Note: As LiveConnectSession states about AuthenticationToken:
The authentication token for a signed-in and connected user.
While check the authentication with Microsoft Graph, I could only find the access_token instead of AuthenticationToken.
UPDATE:
I have checked LiveLogin for WP8 and Microsoft Account Authentication for Mobile Apps via Fiddler to capture the authorize requests. I found that MS account authentication has the similar authorize request as Live SDK.
I assumed that you need to leverage Live SDK to authenticate the user when using client side authentication with Microsoft account. I found the Live SDK download page is not exist, you could follow the Live SDK for WP8 to get started with Live SDK.
UPDATE2:
For the client-flow authentication (Microsoft Account), you could leverage MobileServiceClient.LoginWithMicrosoftAccountAsync("{Live-SDK-session-authentication-token}"), also you could use LoginAsync with the token parameter of the value {"access_token":"{the_access_token}"} or {"authenticationToken":"{Live-SDK-session-authentication-token}"}. I have tested LoginAsync with the access_token from MSA and retrieve the logged info as follows: