Startup.cs

public class Startup
    {
        public Startup(IConfiguration configuration, IHostingEnvironment env)
        {
            var builder = new ConfigurationBuilder()
                .SetBasePath(env.ContentRootPath)
                .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true);

            Configuration = builder.Build();
        }

        public IConfiguration Configuration { get; }

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddDbContext<ApplicationDbContext>(options =>
                options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));

            services.AddIdentity<ApplicationUser, IdentityRole>(option =>
            {
                option.Password.RequireDigit = false;
                option.Password.RequiredLength = 3;
                option.Password.RequiredUniqueChars = 0;
                option.Password.RequireLowercase = false;
                option.Password.RequireNonAlphanumeric = false;
                option.Password.RequireUppercase = false;
            }).AddEntityFrameworkStores<ApplicationDbContext>()
              .AddDefaultTokenProviders();

            services.AddAuthentication( /*o =>
                {
                    o.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
                    o.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
                    o.DefaultSignInScheme = JwtBearerDefaults.AuthenticationScheme;
                }*/ /*Uncomment this if you don't want to use JWT for all of your api*/)
                .AddJwtBearer(cfg =>
                {
                    cfg.RequireHttpsMetadata = false;
                    cfg.SaveToken = true;
                    cfg.TokenValidationParameters = new TokenValidationParameters()
                    {
                        ValidIssuer = Configuration["TokenOptions:Issuer"],
                        ValidAudience = Configuration["TokenOptions:Issuer"],
                        IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes(Configuration["TokenOptions:Key"])),
                    };
                });

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

            services.AddMvc();

            services.AddAuthorization(options => options.AddPolicy("Trusted", policy => policy.RequireClaim("Employee", "Mosalla")));

            services.AddOptions();

            services.Configure<TokenOptions>(Configuration.GetSection("TokenOptions"));
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
                app.UseBrowserLink();
                app.UseDatabaseErrorPage();
            }
            else
            {
                app.UseExceptionHandler("/Home/Error");
            }

            app.UseStaticFiles();

            app.UseAuthentication();

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