Startup.cs

using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.AspNetCore.Authentication.Cookies;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.IdentityModel.Tokens;
using SampleWeb.Authentication;
using SharpReverseProxy;

namespace SampleWeb
{
    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 http://go.microsoft.com/fwlink/?LinkID=398940
        public void ConfigureServices(IServiceCollection services)
        {
            var secretKey = "foofoofoofoofoobar";
            var signingKey = new SymmetricSecurityKey(Encoding.ASCII.GetBytes(secretKey));

            var tokenValidationParameters = new TokenValidationParameters
            {
                ValidateIssuerSigningKey = true,
                IssuerSigningKey = signingKey,
                ValidateIssuer = true,
                ValidIssuer = "someIssuer",
                ValidateAudience = true,
                ValidAudience = "Browser",
                ValidateLifetime = true,
                ClockSkew = TimeSpan.Zero
            };
            services.AddAuthentication(options =>
            {
                options.DefaultScheme = CookieAuthenticationDefaults.AuthenticationScheme;
                options.DefaultChallengeScheme = CookieAuthenticationDefaults.AuthenticationScheme;
            })
                .AddJwtBearer(c =>
                {
                    c.TokenValidationParameters = tokenValidationParameters;
                })
                .AddCookie(c =>
            {
                c.Cookie.Name = "access_token";
                c.TicketDataFormat = new CustomJwtDataFormat(
                    SecurityAlgorithms.HmacSha256,
                    tokenValidationParameters);
            });
        }

        // 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();
            loggerFactory.AddDebug(LogLevel.Debug);
            var logger = loggerFactory.CreateLogger("Middleware");

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

            ConfigureAuthentication(app);

            var proxyOptions = new ProxyOptions
            {
                ProxyRules = new List<ProxyRule> {
                    new ProxyRule {
                        Matcher = uri => uri.AbsoluteUri.Contains("/api1"),
                        Modifier = (msg ,user) => {
                            var uri = new UriBuilder(msg.RequestUri) {
                                Port = 5001,
                                Path = "/api/values"
                            };
                            msg.RequestUri = uri.Uri;
                        }
                    },
                    new ProxyRule {
                        Matcher = uri => uri.AbsoluteUri.Contains("/api2"),
                        Modifier = (msg ,user) => {
                            var uri = new UriBuilder(msg.RequestUri) {
                                Port = 5002,
                                Path = "/api/values"
                            };
                            msg.RequestUri = uri.Uri;
                        },
                        RequiresAuthentication = true
                    },
                    new ProxyRule {
                        Matcher = uri => uri.AbsoluteUri.Contains("/authenticate"),
                        Modifier = (msg ,user) => {
                            var uri = new UriBuilder(msg.RequestUri) {
                                Port = 5000
                            };
                            msg.RequestUri = uri.Uri;
                        }
                    }
                },
                Reporter = r =>
                {
                    logger.LogDebug($"Proxy: {r.ProxyStatus} Url: {r.OriginalUri} Time: {r.Elapsed}");
                    if (r.ProxyStatus == ProxyStatus.Proxied)
                    {
                        logger.LogDebug($"        New Url: {r.ProxiedUri.AbsoluteUri} Status: {r.HttpStatusCode}");
                    }
                },
                FollowRedirects = false
            };

            app.UseProxy(proxyOptions);

            app.Run(async (context) =>
            {
                await context.Response.WriteAsync("Hello World!");
            });
        }

        private static void ConfigureAuthentication(IApplicationBuilder app)
        {

        }
    }
}