How can I get a token from ADAL in Xamarin.iOS?

Question

I want to get a token from ADAL to authenticate a specific server call.

I tried using this code:

var authorityUrl = string.Format(@"https://login.microsoftonline.com/{0}/oauth2/token", AadInstance);
var context = new AuthenticationContext(authorityUrl);
var credential = new ClientCredential(ClientId, ClientSecret);
var authenticationResult = context.AcquireTokenAsync(RemoteClientId, credential).Result;
return authenticationResult.AccessToken;

But I get this in the logs:

AcquireTokenHandlerBase.cs: === Token Acquisition started:
    Authority: https://login.microsoftonline.com/f9e55202-63c0-4821-9fc7-e38eb5bc3a08/oauth2/token/
    Resource: 80d147c1-0b9a-48e0-8a62-1dc82890e98e
    ClientId: cab18d6f-3edc-446b-a071-45b28b192f0b
    CacheType: null
    Authentication Target: Client

TokenCache.cs: Looking up cache for a token...
TokenCache.cs: No matching token was found in the cache
AcquireTokenHandlerBase.cs: System.NullReferenceException: Object reference not set to an instance of an object
  at Microsoft.IdentityModel.Clients.ActiveDirectory.BrokerHelper.get_CanInvokeBroker () [0x0000c] in <f671779d8b3b49399b31bf519785e86e>:0 
  at Microsoft.IdentityModel.Clients.ActiveDirectory.AcquireTokenHandlerBase+<RunAsync>d__55.MoveNext () [0x00389] in <e4081d9da4634689910019c82c03f3e7>:0

I have no idea what could be wrong with this, since the same code works as expected in an Android application, while it does not work in the iOS version.

Answer 1

. , iOS Android , , . . , , . .

, Xamarin ADAL Android, iOS, Win Desktop, Windows Universal. .

Answer 2

:

public async Task<string> GetADALToken(string aadInstance, string clientId, string clientSecret, string remoteClientId)
{
    string body = $"resource={remoteClientId}&client_id={clientId}&client_secret={clientSecret}&grant_type=client_credentials";
    HttpRequestMessage message = new HttpRequestMessage(HttpMethod.Post, $"https://login.microsoftonline.com/{aadInstance}/oauth2/token");

    byte[] byteArray = Encoding.UTF8.GetBytes(body);
    var content = new ByteArrayContent(byteArray);
    // set content type
    content.Headers.ContentType = new MediaTypeHeaderValue("application/x-www-form-urlencoded");
    message.Content = content;

    message.Headers.Add("Accept", "application/json");

    HttpResponseMessage result = null;
    try
    {
        result = await _adalClient.SendAsync(message);
        result.EnsureSuccessStatusCode();
        var v = await result.Content.ReadAsStringAsync();
        return v;
    }
    catch (HttpRequestException reqExecption)
    {
        Log(reqExecption);
        if (result != null)
        {
            return "error " + await result.Content.ReadAsStringAsync();
        }
        return "error " + reqExecption.Message;
    }
    catch (Exception ex)
    {
        Log(ex);
        return "error " + ex.Message;
    }
}