Azure AD Device based Authentication

using Azure.Identity;
using Microsoft.Graph;
using System;
using System.Text.Json;
using WPNinjas.AADDeviceAuthentication.Server;
using WPNinjas.AADDeviceAuthentication.Common;

namespace WPNinjas.AADDeviceAuthentication.Examples
{
    class Server
    {
        static Task<bool> ServerSide(string tokenJson)
        {
            // The client credentials flow requires that you request the
            // /.default scope, and preconfigure your permissions on the
            // app registration in Azure. An administrator must grant consent
            // to those permissions beforehand.
            var scopes = new[] { "https://graph.microsoft.com/.default" };

            // Multi-tenant apps can use "common",
            // single-tenant apps must use the tenant ID from the Azure portal
            var tenantId = "common";

            // Values from app registration
            var clientId = "YOUR_CLIENT_ID";
            var clientSecret = "YOUR_CLIENT_SECRET";

            // using Azure.Identity;
            var options = new TokenCredentialOptions
            {
                AuthorityHost = AzureAuthorityHosts.AzurePublicCloud
            };

            // Generate https://docs.microsoft.com/dotnet/api/azure.identity.clientsecretcredential
            var clientSecretCredential = new ClientSecretCredential(
                tenantId, clientId, clientSecret, options);
            var graphClient = new GraphServiceClient(clientSecretCredential);
            AADDeviceAuthServer server = new AADDeviceAuthServer(graphClient);


            // Validate token, returns true when verified successfully.

            return server.Authenticate(JsonSerializer.Deserialize<DeviceAuthToken>(tokenJson));

        }
    }
}