Http Auth in ASP .NET Core

.gitignore

bin/
obj/

AuthenticationExtensions.cs

using System;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Authentication;
using test.Authentication;

namespace test.Authentication
{
	public static class AuthenticationExtensions
	{
		public static AuthenticationBuilder AddSimpleTokenAuth(this AuthenticationBuilder builder, Action<TokenAuthOptions> options)
		{
			return builder.AddScheme<TokenAuthOptions, SimpleTokenAuthHandler>(TokenAuthOptions.DefaultScheme, options);
		}
	}
}

Program.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore;
using Microsoft.AspNetCore.Hosting;

namespace test
{
    public class Program
    {
        public static void Main(string[] args)
        {
            BuildWebHost(args).Run();
        }

		public static IWebHost BuildWebHost(string[] args) =>
			WebHost.CreateDefaultBuilder(args)
                .UseStartup<Startup>()
                .Build();
    }
}

SimpleTokenAuthHandler.cs

using System.Security.Principal;
using System.Security.Claims;
using System.Threading.Tasks;
using System.Text.Encodings.Web;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Authentication;
using Microsoft.Extensions.Options;
using Microsoft.Extensions.Logging;

namespace test.Authentication
{
	public class SimpleTokenAuthHandler : AuthenticationHandler<TokenAuthOptions>
	{
        public SimpleTokenAuthHandler(IOptionsMonitor<TokenAuthOptions> options,
									  ILoggerFactory logger,
									  UrlEncoder encoder,
									  ISystemClock clock)
            : base(options, logger, encoder, clock)
        {
		}


		protected override Task<AuthenticateResult> HandleAuthenticateAsync()
		{
			if (Request.Query.ContainsKey("auth"))
			{
				var identity = new GenericIdentity("test_user", "queryString");
				var ticket = new AuthenticationTicket(new ClaimsPrincipal(identity), Options.Scheme);

				return Task.FromResult(AuthenticateResult.Success(ticket));
			}

			return Task.FromResult(AuthenticateResult.NoResult());
		}
	}
}

Startup.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;

namespace test
{
    using System.Text;
	using Authentication;

    public class Startup
    {
        // This method gets called by the runtime. Use this method to add services to the container.
        // For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
        public void ConfigureServices(IServiceCollection services)
        {
			services
				.AddAuthentication(o =>
						{
							o.DefaultAuthenticateScheme = TokenAuthOptions.DefaultScheme;
							o.DefaultChallengeScheme = TokenAuthOptions.DefaultScheme;
						})
				.AddSimpleTokenAuth(o => {});
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
        {
            loggerFactory.AddConsole();

            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

			app
				.UseAuthentication()
				.Run(async context =>
						{
							if (context.User?.Identities == null)
							{
								await context.Response.WriteAsync("No user identities");
							}

							foreach (var identity in context.User.Identities)
							{
								var sb = new StringBuilder();

								sb.AppendLine("Identity");
								sb.AppendLine($"  Name: {identity.Name}");
								sb.AppendLine($"  Label: {identity.Label}");
								sb.AppendLine($"  AuthType: {identity.AuthenticationType}");
								sb.AppendLine($"  Authenticated?: {identity.IsAuthenticated}");
								var claims = string.Join(", ", identity.Claims.Select(c => c.Value));
								sb.AppendLine($"  Claims: {claims}");

								await context.Response.WriteAsync(sb.ToString());
							}
						});

        }
    }
}

test.csproj

<Project Sdk="Microsoft.NET.Sdk.Web">
  <PropertyGroup>
    <TargetFramework>netcoreapp2.0</TargetFramework>
  </PropertyGroup>
  <ItemGroup>
    <Folder Include="wwwroot\" />
  </ItemGroup>
  <ItemGroup>
    <PackageReference Include="Microsoft.AspNetCore.All" Version="2.0.3" />
  </ItemGroup>
</Project>

TokenAuthOptions.cs

using Microsoft.AspNetCore.Authentication;
using Microsoft.Extensions.Primitives;

namespace test.Authentication
{
	public class TokenAuthOptions : AuthenticationSchemeOptions
	{
		public const string DefaultScheme = nameof(SimpleTokenAuthHandler);

		public string Scheme => DefaultScheme;
	}
}