Configure Startup.Cs in Asp.Net Core

Question

Hello, I am unable to configure my Startup.Cs to run my application in . Net Core. The following error is being executed:

An error occurred while Starting the application. Invalidoperationexception: No service for type 'Owin.Iappbuilder' has been Registered. Microsoft.Extensions.Dependencyinjection.ServiceProviderServiceExtensions.Getrequiredservice(Iserviceprovider Provider, Type serviceType)

Exception: Could not resolve a service of type 'Owin.Iappbuilder' for the Parameter 'app' of method 'Configure' on type 'PROJETO.WebAPI.Startup'. Microsoft.AspNetCore.Hosting.Internal.Configurebuilder.Invoke(Object instance, Iapplicationbuilder Builder)

Invalidoperationexception: No service for type 'Owin.Iappbuilder' has been Registered.

Below the code of my class Startup.Cs, I appreciate any help!

[assembly: OwinStartup("BANCO_DADOS", typeof(Startup))]
namespace PROJETO_APP.WebAPI
{
public class Startup
{
    //public Startup(IConfiguration configuration)
    //{
    //    Configuration = configuration;
    //}



    //public IConfiguration Configuration { get; }

    public void Configure(IAppBuilder app)
    {
        var config = new HttpConfiguration();
        var container = new UnityContainer();

        ConfigureDependencyInjection(config, container);

        ConfigureWebApi(config);

        // configuracao de autencticacao
        ConfigureOAuth(app, container.Resolve<IProfissionalApplication>(), container.Resolve<ISistemaContextoApplication>());

        app.UseStageMarker(PipelineStage.MapHandler);

        app.UseCors(CorsOptions.AllowAll);

        app.UseWebApi(config);
    }

    public void ConfigureWebApi(HttpConfiguration config)
    {
        // configuracoes pertinentes aos JSONs
        var formatters = config.Formatters;
        formatters.Remove(formatters.XmlFormatter);

        var jsonSettings = formatters.JsonFormatter.SerializerSettings;
        jsonSettings.Formatting = Formatting.Indented;

        jsonSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();
        formatters.JsonFormatter.SerializerSettings.DateFormatHandling = DateFormatHandling.IsoDateFormat;
        formatters.JsonFormatter.SerializerSettings.DateTimeZoneHandling = DateTimeZoneHandling.Unspecified;
        formatters.JsonFormatter.SerializerSettings.PreserveReferencesHandling = PreserveReferencesHandling.None;
        formatters.JsonFormatter.SerializerSettings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore;

        config.MapHttpAttributeRoutes();

        config.Routes.MapHttpRoute("DefaultApi", "api/{controller}/{action}/{id}",
            new { id = RouteParameter.Optional });
    }

    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {


        services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
        services.AddCors();
        services.AddSingleton<IUnitOfWork, UnitOfWork>();


        #region Injeção de dependências de applications

        services.AddSingleton<IAreaApplication, AreaApplication>();
        services.AddSingleton<IAtividadeApplication, AtividadeApplication>();

        #endregion

        #region Injeção de dependências de repositories

        services.AddSingleton<IAreaRepository, AreaRepository>();
        services.AddSingleton<IAtividadeRepository, AtividadeRepository>();
        #endregion

        services.AddDbContext<BANCO_DADOSWebAPIContext>(options =>
                options.UseSqlServer(ConfigurationManager.ConnectionStrings["Banco_Dados"].ToString()));
    }

    public void ConfigureDependencyInjection(HttpConfiguration config, UnityContainer container)
    {
        container.RegisterType<IContextService, ContextService>(new HierarchicalLifetimeManager());

    }

    public void ConfigureOAuth(IAppBuilder app, IProfissionalApplication usuarioApplication, ISistemaContextoApplication sistemaContextoApplication)
    {
        var oAuthServerOptions = new OAuthAuthorizationServerOptions
        {
            AllowInsecureHttp = true,
            TokenEndpointPath = new PathString("/api/security/token"),
            AccessTokenExpireTimeSpan = TimeSpan.FromDays(2),
            Provider = new SimpleAuthorizationServerProvider(usuarioApplication, sistemaContextoApplication)
        };

        // Token Generation
        app.UseOAuthAuthorizationServer(oAuthServerOptions);
        app.UseOAuthBearerAuthentication(new OAuthBearerAuthenticationOptions());
    }


}

}