Self-hosting MVC6 app - owin

Question

I'm trying to get an MVC6 app to be self-hosted for testing. I can do in-memory testing using TestServer, but for testing integration of multiple web apps, one of which includes a middleware that I have no control over that connects to the other app, I need at least one of the apps to be accessible over TCP.
I have tried using WebApp.Start, but it works with an IAppBuilder rather than IApplicationBuilder, so I can't get it to work with my Startup.
Is there any way to get an MVC6 app to be self-hosted in an xUnit test, via OWIN or any other way?
UPDATE:
FWIW, based on Pinpoint's answer and some additional research, I was able to come up with the following base class that works in xUnit, at least when the tests are in the same project as the MVC project:
public class WebTestBase : IDisposable
{
private IDisposable webHost;
public WebTestBase()
{
var env = CallContextServiceLocator.Locator.ServiceProvider.GetRequiredService<IApplicationEnvironment>();
var builder = new ConfigurationBuilder(env.ApplicationBasePath)
.AddIniFile("hosting.ini");
var config = builder.Build();
webHost = new WebHostBuilder(CallContextServiceLocator.Locator.ServiceProvider, config)
.UseEnvironment("Development")
.UseServer("Microsoft.AspNet.Server.WebListener")
.Build()
.Start();
}
public void Dispose()
{
webHost.Dispose();
}
}

Answer 1

Katana's WebApp static class has been replaced by WebHostBuilder, that offers a much more flexible approach: https://github.com/aspnet/Hosting/blob/dev/src/Microsoft.AspNet.Hosting/WebHostBuilder.cs.
You've probably already used this API without realizing it, as it's the component used by the hosting block when you register a new web command in your project.json (e.g Microsoft.AspNet.Hosting server=Microsoft.AspNet.Server.WebListener server.urls=http://localhost:54540) and run it using dnx (e.g dnx . web):
namespace Microsoft.AspNet.Hosting
{
public class Program
{
private const string HostingIniFile = "Microsoft.AspNet.Hosting.ini";
private const string ConfigFileKey = "config";
private readonly IServiceProvider _serviceProvider;
public Program(IServiceProvider serviceProvider)
{
_serviceProvider = serviceProvider;
}
public void Main(string[] args)
{
// Allow the location of the ini file to be specified via a --config command line arg
var tempBuilder = new ConfigurationBuilder().AddCommandLine(args);
var tempConfig = tempBuilder.Build();
var configFilePath = tempConfig[ConfigFileKey] ?? HostingIniFile;
var appBasePath = _serviceProvider.GetRequiredService<IApplicationEnvironment>().ApplicationBasePath;
var builder = new ConfigurationBuilder(appBasePath);
builder.AddIniFile(configFilePath, optional: true);
builder.AddEnvironmentVariables();
builder.AddCommandLine(args);
var config = builder.Build();
var host = new WebHostBuilder(_serviceProvider, config).Build();
using (host.Start())
{
Console.WriteLine("Started");
var appShutdownService = host.ApplicationServices.GetRequiredService<IApplicationShutdown>();
Console.CancelKeyPress += (sender, eventArgs) =>
{
appShutdownService.RequestShutdown();
// Don't terminate the process immediately, wait for the Main thread to exit gracefully.
eventArgs.Cancel = true;
};
appShutdownService.ShutdownRequested.WaitHandle.WaitOne();
}
}
}
}
https://github.com/aspnet/Hosting/blob/dev/src/Microsoft.AspNet.Hosting/Program.cs

Answer 2

You can use Microsoft.AspNet.TestHost
See http://www.strathweb.com/2015/05/integration-testing-asp-net-5-asp-net-mvc-6-applications/ for details on use.
TestHost can work with your startup using a line like
TestServer dataServer = new TestServer(TestServer.CreateBuilder().UseStartup<WebData.Startup>());
where is the name of the application. The application has to be referenced in the test harness