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.Identity.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using IdentityServerWithMySql.Data;
using IdentityServerWithMySql.Models;
using IdentityServerWithMySql.Services;
using Pomelo.EntityFrameworkCore.Extensions;
using IdentityServer4;
using Microsoft.IdentityModel.Tokens;
using Microsoft.AspNetCore.Http;

namespace IdentityServerWithMySql
{
    public class Startup
    {
        public Startup(IHostingEnvironment env)
        {
            var builder = new ConfigurationBuilder()
                .SetBasePath(env.ContentRootPath)
                .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
                .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true);

            //if (env.IsDevelopment())
            //{
            //    // For more details on using the user secret store see https://go.microsoft.com/fwlink/?LinkID=532709
            //    builder.AddUserSecrets<Startup>();
            //}

            builder.AddEnvironmentVariables();
            Configuration = builder.Build();
        }

        public IConfigurationRoot Configuration { get; }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            // Add framework services.
            services.AddDbContext<ApplicationDbContext>(options =>
                options.UseMySql(Configuration.GetConnectionString("DefaultConnection")));

            services.AddIdentity<ApplicationUser, IdentityRole>()
                .AddEntityFrameworkStores<ApplicationDbContext>()
                .AddDefaultTokenProviders();

            services.AddMvc();

            // Add application services.
            services.AddTransient<IEmailSender, AuthMessageSender>();
            services.AddTransient<ISmsSender, AuthMessageSender>();


            services.AddIdentityServer()
                .AddTemporarySigningCredential()
                .AddInMemoryPersistedGrants()
                .AddInMemoryIdentityResources(Config.GetIdentityResources())
                .AddInMemoryApiResources(Config.GetApiResources())
                .AddInMemoryClients(Config.GetClients())
                .AddAspNetIdentity<ApplicationUser>();
        }

        // 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(Configuration.GetSection("Logging"));
            loggerFactory.AddDebug();

            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
                app.UseDatabaseErrorPage();
                app.UseBrowserLink();
            }
            else
            {
                app.UseExceptionHandler("/Home/Error");
            }

            app.UseStaticFiles();

            app.UseIdentity();
            app.UseIdentityServer();

            // Add external authentication middleware below. To configure them please see http://go.microsoft.com/fwlink/?LinkID=532715
            //app.UseGoogleAuthentication(new GoogleOptions
            //{
            //    AuthenticationScheme = "Google",
            //    SignInScheme = IdentityServerConstants.ExternalCookieAuthenticationScheme,
            //    ClientId = "708996912208-9m4dkjb5hscn7cjrn5u0r4tbgkbj1fko.apps.googleusercontent.com",
            //    ClientSecret = "wdfPY6t8H8cecgjlxud__4Gh"
            //});

            app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller=Home}/{action=Index}/{id?}");
            });
        }
    }
}